I have been speaking with Solar City's commercial division about doing large grid-tied solar projects with Tesla batteries in one of USA largest cities and have $100M in projects under development.
These batteries aren't going to power your home at night, nor should they as electricity rates at night are dirt cheap (comparatively) when people aren't at work, in factories and in bed sleeping.
These batteries are going to be performing grid marketplace arbitrage and some governments and utilities are providing amazing incentives to do so. (Currently the incentives require the batteries to be tied to solar.)
There are two pieces of your electricity bill (I'm simplifying here) 1) the electricity charge (EC) and 2) the transmission charge (TC). The EC is calculated by how many kWh you use during each (peak/off-peak) period of the day and the TC is calculated by your max grid demand during your largest 15 minutes for the month.
Tesla Batteries are not just about the batteries, the system calculates how to remove kWh demand from peak hours by pulling power from batteries and then recharging during off-peak hours. This covers the EC cost reduction.
To reduce TC costs the system calculates your peak load over the given month and tries to turn it from a "mountain range" (with many peaks) to a "platou". You pay your TC for the tallest mountain for the month. At first the system doesn't know that much about your usage profile and will just focus on the largest peak demand 15 minute intervals. Then over time it will learn more about your usage patterns and slowly platou your grid demand.
At the end of the day it is going to be much more cost effective and efficient to have a distributed grid with thousands of solar arrays and batteries than build out large billion dollar gas fired turbines or even wind turbines.
I was with you until you said that distributed energy is more efficient than large scale energy.
A large scale hydroelectric, battery, or wind plant will be far more efficient than distributed energy in the home. Solar may benefit from capitalizing on under utilized residential real estate, but absent that incentive, a large solar plant will also be more efficient than a distributed per home grid due to standardized install and maintenance, larger inverters, and optimized layout (most home systems are non tracking).
You are also missing the cost of the distribution and transmission infrastructure, which distributed generation avoids in addition to the transmission losses
Distributed generation using solar or wind without distributed storage actually needs more transmission infrastructure than centralized generation.
That's because of unpredictability of these power sources.
With centralized generation you can do hierarchical network, with smaller capacity further "downstream".
With distributed you need P2P network, and when some part of country has no sun and no wind - you need to be able to get that energy from other sources.
Distributed storage changes the game, but it depends on the costs.
>> should they as electricity rates at night are dirt cheap
I dont know where you are but my electric rate is the same night or not... I pay the exact same rate 24/7
I do not have demand based pricing which is reserved for business customers or persons consuming a crap load more power than I.
>>At the end of the day
the Power Companies are doing their level best to penalize home use Solar, they want to charge home owners through the nose if they "sell" power back to the grid eliminating any costs savings and in come cases making a roof top solar project more expensive than just buy power from the mafia err power companies.
Distributed non-grid power should be the goal, Grid power needs to be phased out.
That's not necessary malicious on the part of the power company.
At a previous job, we built a system for a company that prepared batteries through multiple charge/discharge phases. During a discharge, the power was pushed back onto the grid.
The major challenge was matching the waveform of the grid power (occasional spikes confusing the zero-crossing, drift on the timer elements etc.). If you don't, it reduces the efficiency of the power company's transformer leading to replacement with a larger one, or damage due to the excess heat. You can imagine they're going to recover that expense from somewhere (and you and your dirty sine wave are pretty clearly at fault).
I would expect the home systems to be less precise than our industrial client's equipment.
I never got the point of storage heaters. They're completely useless in the evening when you want heating. Much of the heat escapes when they're on overnight (while in bed so little need for it) and the rest during the day while you're at work.
As I understand it the big problem is the "duck curve," the spike in demand that occurs immediately as the sun sets when there's a lot of solar. If the batteries could smooth that out, that'd be pretty huge in helping solar adoption.
This is also the missing piece to move over to a more renewable energy source. Coal is on demand. If there is a need for more, you can spin up more factories, and many site waiting just for this.
Most renewable energies are reliable, but over longer periods of time. With a way to store energy, and have it dormant in the grid waiting to be used, this creates the surplus needed so we can switch to solar and wind and be able to rely on output.
Your point is correct, but the details are wrong: coal (and nuclear) provide so-called "baseload" power, while natgas and hydro provide "peak" power (this is why natgas plants are called peakers). Coal has a very long spin-up (and spin-down) time. If you've studied process control, the first-order time delay is on the order of hours to days. Natural gas and hydro have time constants of ca. minutes. Moreover to your point, batteries have very short time constants (but a plethora of of other problems).
As has been mentioned, the boilers themselves do not heat up that quickly; however, you _also_ have to mix the pulverized coal with hot air and then pump it into the firebox for combustion.
If you're coming up from a cold start, you're going to need to pre-heat the air, probably with electricity and/or natural gas. With this in mind, it's not so much that they don't generate power right away, it's that they don't generate enough power to overcome the cost of their initial inputs.
From a power plant perspective, you aren't "started" until your output power is larger than your input power.
For coal, I think it is because of the large turbines used. They have to be brought up to temperature gradually because they are very large precision made hunks of metal.
That's very likely due to size. Things like powerplants get more efficient as they get larger. (And as they get more complex by piling on more optimizing subsystems.)
This is the answer. Commercial power penalizes you for having a large difference between your peak use and continuous use. If you can eliminate peaks using batteries you can eliminate this penalty. You can also recharge the batteries during off hours to cut costs further.
Unless you have a particular reason to worry about your connection to the grid, it's better to use demand management than batteries.
Let's take a Tesla S battery. It costs $30,000 [1]. It has a capacity of 85KWh, which lasts 265 miles. [2] The battery is down to 80% life after 100K miles [3], which is 377 cycles.
Say you fill up the battery at 5 cents/KWh and sell it at 20 cents/KWh. You've made $12.75. After 377 cycles, you've made almost $5000. You still have life in those batteries, but they are going to keep on getting worse, and the efficiency of energy in/energy out will start falling as well. Once you hit 40% they are probably useless. You might be able to run that $5000 two or three more times before you hit that.
You could only barely use the batteries to prolong their life. But you spent $30,000 on them! That's a lot of capital costs for something that isn't doing anything. And Li-Ions will gradually lose capacity even if you don't use them and store them in ideal conditions.
There are certainly efficiencies of switching from a car-bound battery to a stationary battery, although a lot of people posting on this page are talking about hooking up a car to do price arbitrage.
Well thought-out post, however, your math is singularly reliant on the 30,000$ price tag for the battery and although you did list the source, it's accuracy is in some doubt. First of all, you can pre-buy a replacement Tesla battery for 12,000$(source: found in your same link [1]), secondly, the information is old.
I don't think there is any doubt that the number has come down significant. I'm sure you are aware that Tesla is building out a huge battery plant, significantly increasing lithium batter production ability, this will absolutely bring batter prices down.
I would be extremely surprised if their own internal numbers show a pay-off time of longer than 3 to 5 years. It's not like Tesla doesn't have people who get into the numbers, as the numbers are the only thing that is going to sell.
I would expect the car is a much more harsh environment for the battery than my house. I'm not talking about vibration or temperature, though those matter, but electrical demand. A model S has a 310kW motor. Nothing in my house comes anywhere close to demanding 310kW. Of course the Tesla will rarely require the full 310kW, but its charge and recharge cycles are at the mercy of your driving.
You could smooth out the peaks in my home demand with probably just 10kW. Perhaps smooth out many of my neighbours peaks with 50kW. But my point is that there are no hard bounds that the battery needs to satisfy, unlike in a car when you have to supply the drive current or sink the brake current. You can tune a home battery's charge/discard cycles for maximum battery life rather than maximum performance. I don't have data for how much difference that would make to battery life, but I would guess it may be significant.
if the battery has capacity of 85 kWh and you're saying the motor consumes 310kW at max, then that would mean a model S only has a range (time) of 16 minutes?
Tesla estimates about 300 miles per charge at 60 MPH
(300/60 = 5 hours)
Every time you accelerate, you're drawing way more current from the battery than you do cruising at highway speed. So the average power draw is 17 kW/hr, but some of that happens in great bursts.
Using batteries seems like an insanely cost and environmentally-unfriendly way to engineer around billing practices of electrical utilities. I think we'd be much better off trying to get the numbers up for solar (installations, efficiency, lifespan, manufacturing) vs using vast quantities of highly toxic batteries powered from the grid from traditional power generation sources to game electrical utility billing for profit.
I really don't understand why this idea seems so popular with e.g. politicians.
Without weight constraints of a car, you can use larger fire-containment-cell sizes, significantly lowering manufacturing costs. Also, you are ignoring the value you can get back when you recycle the battery, which may be part of how Tesla is offing the $15,000 replacement.
I still don't know if the numbers would work out though.
I'm not sure that it is a safe assumption that this stationary battery will be based on lithium-ion cells. In the past, simple lead-acid batteries have far outperformed lithium-ion batteries in situations where weight and volume were not an issue.
I assume the primary issue now is cost, but if you can decouple the reaction -> electricity engine from the reactants to a greater degree, then it sounds attractive? I imagine increasing storage tankage is a much easier problem to solve than increasing energy density.
Wholesale LMPs are often more like $80/MWh at peak and -$60/MWh at nega-peak, but that still works out to 14¢/kWh, which is about the same difference you're calculating with.
Yep ... This idea has been around for a long time (Hydrokinetix was building ETS systems in the '80s) but a great battery will allow the technology to go mainstream. It's cool to hear that you've got such a backlog of orders!
I like the idea of having solar cells that charge up a bank of batteries that could power my house at night. I was recently talking to a Solar City rep and they are thinking along those lines.
I wonder if this would be a good time to define a standard low voltage plug for house hold use. An awful lot of modern electrical devices don't need 110VAC and end up wasting a lot of power converting AC to DC. I've seen replacements for wall sockets that combine a single AC socket with a few USB power ports. That's convenient, but USB wasn't designed as a power plug, it's just been co-opted for it. A well designed system of 24VDC or 48VDC would be a nice thing to have. Bonus points if it's a world standard. I'd also like a pony.
The problem with low voltage power is power loss during transmission. Power in a circuit is voltage times current:
Watts = Volts * Amps
Power lost in transmission is current through the wire times the voltage drop across the wire. The voltage drop is easy to figure out with Ohms law:
Volts = Amps * Ohms
Rewriting these with V = voltage, I = current in amps, R = resistance in ohms and P = power in Watts and simplifying one gets:
P = V * I
P = (I * R) * I
P = I**2 * R
So power losses are proportional to the square of the current flowing through any given piece of wire (that will have a resistance independent of the voltage or current).
My house has 20 Amp circuits at 120 Volts. The same power transmitted at 5 volts needs 24 times the current (i.e. 480 Amps) and 24^2 times the copper in the transmission wire to have the same power losses. So I would basically need a wire with 576 times as much copper to have the same power loss in that one low voltage circuit.
This is why it isn't practical to run the whole house on low voltage. High efficiency transformers can step up or down a voltage while losing only a few percent of the power. When their output voltage is 10 times higher their output current will be 10 times smaller and can be transmitted over the same wire with only 1 percent of the original voltage's transmission power loss.
This is the reason that power transmission lines run at 120,000 volts--a million times lower transmission line losses. (It actually is a bit more complicated due to the alternating current interactions, but it's the basic idea.) Power transformers can be 99% efficient. I have no idea of the power losses that would occur between DC current from solar panels to 120 VAC and then back to 5 VDC for USB, but you definitely don't want to transmit 5VDC over long distances.
Thanks, I'm getting a great understanding of all of this from the comments here. I suspect that USB is going to end up being the universal low-voltage power source, but I still think that's a shame, as something more like 24 to 48V would be better, especially if there was a well designed, universal connector.
I'm still amazed that they can get 100W out of those tiny USB wires...
The 100W delivery over USB actually bumps it up to 5 amps at 20V. The higher power profiles aren't available by default until the devices negotiate the higher voltage and confirm that the cable can support it.
With how much USB cables get beat up, staying on the lower end of voltage is probably a good idea. I've definitely seen some old ones that ended up with wires exposed. But 20V is definitely more capable than the old 5V. You'd need a lot of copper to run 100W at 5V.
I think the idea is use these only for low wattage applications, way below 2400 Watts. 48V at, say, 10A is plenty of power for many uses. Also the transmission distances should be relatively short if coming from a battery in the home.
The cross over is surprisingly early. I care for a cabin that uses a 24VDC battery for its solar power storage. I run that in #6 copper to the cabin (pencil thick conductors). I regularly see a >2 volt drop on that run when the tiny high efficiency fridge kicks on, on top of the ~40watts that the telemetry and comm gear takes. You wouldn't notice that on a 120v line, but that's 10% of my power gone to heating the earth.
Given a do-over on infrastructure, with today's equipment costs, it would save up front capital and power to use a small inverter at the batteries and run those items off of AC using smaller copper lines for the long run. Keep in mind that you still need DC-DC converters at the loads, since nothing is going to want to run off of your varying DC socket voltage.
(Batteries closer to the cabin is not a win, the solar panels are off that direction and those lines need to be kept short too. I do have a large inverter in the battery shed and send 120v to the cabin for big loads, but its idle current is too high to keep up for the base loads. The most expensive part of this spring's wind turbine installation (and heaviest) is the copper wire. Low voltage DC is not an answer.)
The new USB standard supports up to 100 watts per port, which is sufficient to many applications.
If we accepted 20 amps as the current rating, a 12v ride-on system would offer 100 / 5 * 12 -> 240 watts, which seems low, except that DC, especially if well filtered, stacks in parallel and series much more composably than AC.
The cigarette charger standard plug sucks though, and there's a limited window of opportunity to replace it.
Yeah, we have two standards now, auto cigarette sockets and USB, neither of which is optimal. And I agree, the window of opportunity here is narrow and I'd hate to see us miss it.
Oh, and to address the comment on wattage, I should have made clear I don't want to eliminate AC sockets where they are needed. I'm just looking at having DC in the wall as a convenience and efficiency thing and a way to reduce the number of power adaptors I need.
What could a new standard do that usb can't? Next generation is reversible, there's little to no chance of touching a half plugged in plug and get shocked. It seems pretty good to me.
There's the security downside of plugging in a data capable port when you think you're just getting power. I know this isn't worth consideration for most people, though, and there are "condoms" to deal with it. Still, it'd be nice if we could fully rely on charging devices with no chance of being attacked, like dedicated power systems in use on most laptops today.
No, but when you bring a charge adapter for normal electric, there's no risk. Whereas as USB gets more universal, you're less likely to bring your own charger, or even your own cable, opening up attack vectors.
There's probably no mass-appeal way to satisfy both goals.
I've often wondered if someone would make a DC outlet strip. As the typical one has a half dozen "wall wart" type power supplies plugged into it, doing the conversion to say 24VDC and then down converting from there seem to be more convenient. But efficiency wise its something of a wash.
And from a whole house perspective, I keep hoping for a capacitor (storing charge directly rather than in chemical bonds) which would give me back most of the energy I had stored.
That is sort of becoming a thing with USB outlets. It is starting to become quite ubiquitous. I wouldn't be surprised to see an outlet that had 4+ USB ports and a standard outlet maybe.
> Also, USB outlets still down convert 120V AC. It'd be much better to do it in bulk at once place in the house and let devices use that
That's not entirely clear. Low-voltage DC has higher transmission losses, so converting to USB-level voltage in one central location might do quite a bit worse. Plus, you still need logic at the plug to detect how much power to supply.
This is my opinion as one. Switching supplies are 90+ efficient, at nominal load and they are less efficient below and above that nominal load. So your 48VDC converter might by 87% efficient because its rated for 500W and you're only drawing 50. And your 5V regulator may be only 92% efficient while your device is charging but 88% when your device is 'idling'.
Is there any plug system for automatically stepping voltage based on the plug design, so people wouldn't have to set it manually? Like say you had 24v as the base, using a plug with 4 prongs gives you the full 24v, a plug with 3 prongs gives you 12v, 2 prongs gives you 6v, etc...
Almost all the power connectors used inside a desktop PC have at least two voltages. For example, a hard drive will usually draw from only the 5V and 12V pins, but some SSDs are designed to use 3.3V.
The problem with these connectors is that they usually aren't designed for many plug/unplug cycles. The SATA power connector is also nearly unique in being designed for hotplugging by ensuring that the ground pins make contact first and disconnect last.
I was under the impression that a capacitor takes twice the amount of energy to charge than what is actually stored within it. i.e. efficiency is a maximum of 50%.
Modern switching transformers are pretty darn efficient. I think it's very unlikely that the losses from converting AC to DC would outweigh the transmission losses you'd get from using low voltage DC (even over the short distances inside a house).
I would love to see a Fermi estimate of this, I'm afraid it's outside my bailiwick.
The proposal would be 48VDC (pretty standard for panels) to 120VAC 50Hz, back to 5 and 12 volt at the application, versus sending 12 and 5 volt around a house, call it 10x10 meter perimeter and pessimize the layout (some outlets go all the way around the house).
My strong sense is that the single-step conversion beats the three-step, but losses transmitting low voltage DC are substantial.
Sending 12V around a 22' boat leads to voltage drops that are beyond the tolerances of many of the devices that consume 5 and 12 volt DC. Sending it around a whole house would require stupidly thick wires to stay within ATX spec (5%).
Of course, if you're running off a battery it's DC to start with, so you're avoiding using the inverter.
If houses started coming with standardized low-voltage DC alongside the regular 110 AC, manufacturers could perhaps start selling CFLs and LEDs without builtin transformers. Although I'm not what voltage they actually run on internally.
CFLs require a switching power supply because they operate at far higher voltages than line voltage. LEDs require some sort of current regulator, and a switching power supply is far more efficient than a series resistor. So, you don't gain anything for them by using a different voltage.
Yeah, I wondered about that, but my electronics-fu is not up to analyzing it. Running low voltage DC from one end of a large house to the other might simply not be practical. I'd still like to see a low-voltage plug standard other than USB and cigarette sockets, even if the conversion was being done inside the electrical box in my wall. I see the huge number of wall warts I have as a source of needless duplication and waste. (They are also, I understand, a revenue source for vendors selling replacements at inflated prices, so there is an economic incentive for the status quo.)
Running off-grid solar cell systems has been quite popular in the hobbyist space for a while. There are tons of products and examples out there for DIY installations. These generally use lead-acid batteries and inverters to convert DC up to 110 VAC for your house.
There are already DC power standards used for electronics, too. Telecom equipment commonly uses -48 VDC. However, I expect that you will find that the majority of your electricity is used by motors and other appliances that run directly off of 110 VAC.
Exactly. And not even just in hobbyist space. There is a long-established history of running homes off of solar power using lead-acid batteries in professional installations. And not even just in homes; many, many businesses have invested in it. The only barrier is financing... and companies are even forming California to amortize the financing of solar to the home, so home owners can get started with ~$200/month instead of a $20k installation.
There, the possibility that a "Tesla" battery could do anything the same or better is not new, redundant and this article is just marketing hype: It's a report of an investor call, for crying out loud, not researched journalism. There is no reason to expect a lithium battery in the home would be cheaper than traditional, established lead-acid batteries.
The advantage of lithium in a car is obvious (weight, if you haven't had your coffee). In the home, weight is not a factor. Lithium would save space, but at the expense of lifetime and cost. Since cost is the only factor holding back installation now, I don't expect many people to pay even more for the privilege of a lithium home battery bank.
BTW, in reference to your expectation, a motors expert I work with says that 50% of all electricity consumed is consumed by motors. The refrigerator's compressor motor is generally the heaviest electricity consumer in the home.
The barrier is batteries and the cost of them. I briefly looked into this. To run my house's essentials: heat, water, fridge, and 1-2 outlets for electronics I currently use a 5KW generator when the power goes out. I have a transfer switch that shows me my peak current: roughly 2.5-3 KW when the well and fridge are running. A deep cycle marine batter that you can readily buy from Amazon costs $100 or so and gives you 12 Volt 35AH. That's 420 Watt hours. Thus to run just the bare essentials in my house for 1 hour, I'd need 7 of these (assuming perfect DC to AC conversion). To run for 24 hours, I'd need 168 of them. So I am investing $16,800 in just batteries. But don't forget, that there will be periods of cloudy days, so you want enough capacity to get through those. I haven't seen the sun here in CT for about a week now... Oh, and in the summer, I do like my AC which itself pulls 5kW and has a relatively high starting current. I'd have to quadruple the capacity to run it. My basement is simply not large enough to contain all these batteries + inverter system. Doing all this to save under $200/month on the electric bill will never pay for itself.
A low cost space saving battery with high energy density would be pretty game changing here.
As you probably know, lead-acid also requires more maintenance than Li-Ion. Li-Ion's nice selling point for consumers is that you don't need to (especially) worry about stuff like battery memory.
Why do we need to use a chemical battery for large things that aren't mobile? Why can't we store kinetic energy by, say, raising and lowering a big counterweight?
Steel is 36 cents per pound. Assume you can move it up and down 300ft (30 story building). This will get you 1pound * g * 300ft of energy storage. This comes out to 300,000 USD/kWh, about a 1000 times more expensive than Li-ion batteries, per kilowatt-hour.
"The main problem with gravitational storage is that it is incredibly weak compared to chemical, compressed air, or flywheel techniques (see the post on home energy storage options). For example, to get the amount of energy stored in a single AA battery, we would have to lift 100 kg (220 lb) 10 m (33 ft) to match it. To match the energy contained in a gallon of gasoline, we would have to lift 13 tons of water (3500 gallons) one kilometer high (3,280 feet)."
It would be nice to re-think the necessity of AC, as well. It's been around for quite a long time and the ineffectiveness are crazy (same thing with whole-house heating). Why heat or cool your house and deal with the insulation problems that come from having doors and windows and walls and exposure to sun or wind on one side? Your house doesn't get hot or cold, it doesn't care. You get hot and cold.
Supercomputers run on batteries for an entire day or more in our pockets. Powerful mobile gaming machines can be run from a USB socket. There has to be a way to cool me down in the summer without needing to cool my entire house (and watch as the cold air streams out underneath my door).
I am guessing you live alone. Try telling a one year old to put on a snowsuit to eat soup in. Or your dog. When the weather is -40 degrees, a sweater won't save you. When it is 110 you will need a trunk with batteries behind you to power your personal AC 24/7. Give it a try and turn off the heat and AC for a season. You might make it, but will it be worth the $100-200/month?
Edit: don't forget that AC is much more efficient than heating. With AC you are looking to change the temperature by at most 35 degrees and you are moving heat, so you are getting a multiplier there. With heating, you are heating from freezing or below for most places.
> Edit: don't forget that AC is much more efficient than heating. With AC you are looking to change the temperature by at most 35 degrees and you are moving heat, so you are getting a multiplier there. With heating, you are heating from freezing or below for most places.
Its also incredibly efficient if you're using a geothermal system to pull cold out of the ground vs pushing heat into existing hot air with a compressor.
It can be, assuming you are in the right location in the world. The problem is cost efficiency: you are talking about tens of thousands of dollars for a system that will only pay for itself in a decade (often times; in some situations this is the perfect answer). Geothermal is no silver bullet unfortunately. There is physical efficiency, and there is economic efficiency.
I don't live alone, and I live in a place where the weather occasionally dips to -30F wind chill (and in summer occasionally hits 90F), so I understand hot and cold weather. I have a family and pets.
Literally every single person who commented on this has completely and 100% failed to read a single word I wrote. You're wrong, you're missing the point, and it seems like you're intentionally being obtuse.
Sorry if this sounds snappy, but I've read and re-read my original post over and over again and I'm not seeing why everyone interprets it as me telling them AC and heat isn't necessary. Things like "It would be nice to re-think the necessity of AC, as well" and "There has to be a way to cool me down in the summer without needing to cool my entire house" don't mean "turn off your climate control", they mean "let's get better climate control".
Your comment is exactly the kind of thinking that I was arguing against. Right now we need AC and heat for the entire house. Just a few years ago, we needed gasoline to power our cars and just a few decades ago we needed a dedicated room to run a calculator.
I have a coat with a battery that heats up just the coat for when I'm outside in winter. Shrink it to a normal long sleeve shirt that you would wear inside anyway. That's a start. The point is, we need heat/AC now, but are they the best we could possibly do? And is forced air the best we can do?
I believe I understand you correctly. You want some type of smart system to heat/cool only what's necessary. Fair enough, and maybe there is even something to it. I do see problems with it.
If you are talking about a per-room system, latency becomes an issue. If I go from my bedroom to my bathroom, how long must I be in the room until the heat comes on? Moreover, won't turning heat on/off put a lot of strain on the system? This is not convenient. It's an actively worse system than what I have now. Additionally, I'll spend much more energy heating each individual room, unless I have insulated doors and inside walls: another huge expense.
If you are talking about everyone wearing electric coats and blankets and their AC equivalents, forget about it. First, you have to carry a battery pack and charge it every so often. Second, where you used to be able to just turn up the AC a bit and wear shorts, now you have to wear a spacesuit to not suffocate in the summer.
I think HVAC could definitely use innovation, and this goes beyond the really expensive geothermal systems or high efficiency condensers. Boring things like insulation and construction materials is what's going to make a huge difference here. Buildings with good insulation and little air exchange with the outside will use significantly less energy than those with poor insulation. Heating being the #1 consumer of energy in any given house, we need to trap it inside for as long as possible. Remember, it's much easier to insulate a wall that's not moving, sitting, bend, bathing, etc. than a human.
In short, I understand what you are saying, and I think that others on here do too. I simply disagree with it.
Maybe you could have made that post first, rather than "you're wrong, we need AC exactly the way it is".
Look at it like this: in 2006, who thought that having phone that needed to be charged every night and was crazy expensive and ridiculously fragile was a good idea? Sure, there were some people who had a Palm or a Windows Mobile phone, but they weren't very good. Just like people have hand warmers and electric blankets, which are bulky, inconvenient, and not very good. The the iPhone came along and was slightly better, but better enough that people would take it seriously. Maybe something like the Nest fits that analogy. Then suddenly with a few small tweaks and a change of public mindset, everyone is carrying a 12-hour-battery-life, $700, all-glass smartphone in their pocket, to the point where PCs are being phased out and hardly anyone has a house phone anymore.
So what you're saying is, we need mainframes and house phones, but maybe we should have cordless phones and network those mainframes together, because the problem of making a smartphone is just too hard.
So no, I don't think you understand. You know what's not convenient? Walking out the door and having my face frozen off by -30F weather. Having an AC unit in the living room where the cold air never reaches my bedroom at night. Bundling up in the winter. Sticking to the leather in the summer. You want to talk about convenience? That doesn't sound very convenient at all. That just sounds lazy, because it's what we have now. Lazy is not the same as convenient.
Do you have a cell phone, or are batteries too inconvenient? With current HVAC systems, you only have them in your house, your office, or your car. I used to have a bag phone in my car that I could plug into the cigarette lighter. But now I can take my phone anywhere. Why can't I take my HVAC anywhere?
No, there are suits that circulate water to keep someone cool, hand warmers to use for hunting/ice fishing/etc, ice packs that you can wear strapped to your body, and probably many more I've not yet seen. Problem is, they're just not that good. But electric cars weren't that good not that long ago either, so there's room to grow in the space.
Anyone who lives near SF will be used to living in a $2000/month apartment with no A/C, or for that matter the whole nation of Japan.
Not sure exactly how much more efficient it is, but it sure builds character. It also helps that the winters are not too bad, and the summers are only kind of too bad.
Easy answer... it's convenient. You show me a people warming/cooling solution as convenient as whole home heating and cooling and then the conversation can begin. It's about creating an environment to live in that is consistent, has nothing to do with a house's feelings.
I honestly thought I was talking to a group of engineering-minded people. This comment? This is where dreams go to die.
But I guess there's no room for improvement, which is why heated seats were never invented in cars, why hand warmers were never invented, why heated jackets don't exist, why we don't have ice packs, etc. Those things would be crazy and useless.
Maybe you are missing the point here. Heated seats in cars do not replace the heating system in the car. Hand warmer, heated jackets are for outside, not inside. Do you want to walk around, inside your house in a heated jacket and hand warmers? It isn't nearly as convenient as having your house be 70 degrees, or whatever you deem comfortable.
agree. Also, you need to heat your house here in Michigan if you don't want your water pipes to freeze... or your kid's pet cockatiel to die or suffer.
I have a bathroom where the water pipes pass through an outside wall. On nights where the temperature goes below 0 degrees F, I open the cabinet door under the sink so heat can get in there. My thermostat is programmed to drop to 60 degrees F at night but because the thermostat is across the house, our downstairs bathroom gets very cold. It's on a slab too. Pipes always freeze if we forget to prop the door open and the temps get down below or in the single digits.
I had been thinking of getting one of those wires you put on the pipe to keep it from freezing but it's behind a wall and very hard to get too...
Curious... I live in suburbia where putting solar panels on one's domicile would most likely be met with an order to remove or fines.
I had an experimental panel in my backyard to provide power to a work shop shed. The shed was there when I purchased the property & house. About 6 months after planting a pole in the ground, behind the shed, but in view to my neighbors garnered a letter from the township where I live that basically said to remove it for being an eye sore.
I don't think people realize how many restrictions are put on their property--mainly my small towns, and entities. Every
year Busy Bodies(usually retired with no interests), or local politicians looking for something to do; complain, and enact these rediculios laws. They are essentiall eye sore laws, and usually originate from people who should never talk about
aesthetics. You buy a piece of property and really can't
do much to it. I would like to call out my own town, but I
have shared too much here--they could probally harass me in some way?
I would look into fighting whomever told you to remove the solar panel. I thought solar panels were protected by Federal law? In my town, I couldn't put up a car shade for
one day--without risking a ticket. I don't know what country
you are in, but in the United States we have way to many laws. "Oh it sounds good, and doesn't effect me; let's enact
a law prohibiting it."
there is no HOA. The township sent me a letter saying it violated some ordinance about affixing stuff to the ground like a flag pole. It was affixed to the ground with a solar panel on top of the pole. I've contemplated moving the panel to the roof of the shed where I think they wouldn't have an argument then.
That's crazy. What, they hate tax credits? I'm glad I live in middle of a smallish city, where the 20 panels on my roof don't raise any eyebrows whatsoever.
Yes, I'm thinking of doing just that. I'm sure the neighbors complained about the eye sore and so they used an ordinance to force me to take it down. So, yes, moving to the roof I think might work.
Would you mind posting a link to the ones that look like shingles?
I know that the company 'Eternit' has roof tiles called 'Solesia'; real 'shingles' I haven't seen in real life myself, but one of the first Google hits is http://www.dowpowerhouse.com/ .
We had 110VAC & 12V DC wall plugs on our boat. It wasn't exactly fool proof (there was just a label above each that said AC or DC), but it totally worked if you knew what you were doing. We had a bunch of devices that could plug into 12V DC directly and avoid the inverter penalty. Phone chargers, lamps, laptop chargers, etc.
my Chrysler Town & Country van has 110v outlets in the rear of the van. Occasionally, we trip the breaker but for the most part it works rather well too.
There are problems with using DC in a consumer environment incresaed losses and nore fires ( problem in Amrica with its use of wood as abuiding material)
Talk to any telecoms workers and they will tell you amusing stories about acidents with the DC supply - the Painters shorting out the bussbars whilst decorating an Echange (Central Office) was one I remeber.
48 V might be posble but that means 2 Diferent sets of wireing.
There are already widespread programs where utilities pay customers a rebate in exchange for remotely turning off their A/C compressors at the peak of a heat wave in order to chop the top off consumption spikes. Paying high-consumption commercial customers to turn off entirely for a few hours to avoid spinning up another generation plant happens too.
It's not too far-fetched to imagine a rebate program on home battery systems if the utility got the same remote control power to disconnect homes from the grid when needed, or even have their batteries dump power back onto it at those times. Essentially, individual homes become part of "smart grid" management systems.
Beyond that, you can opt into paying a real-time price for electricity (like the utility does) instead of a flat rate. You're at the mercy of the market but can save a significant amount if you voluntarily turn off high consumption devices during peak periods and schedule other loads for overnight or slack periods.
What really gets interesting are the times (especially during early summer mornings) where there's too much supply on the grid and the price drops into negative territory (i.e. they'll pay you to shed load off the network). That's when you need the storage system charging up as fast as it can. I've been working on a personal system that watches the price and other factors (weather forecasts, family schedule) and cycles the A/C as deep as possible during those times.
What might really suck though is if everyone has one of these in their homes, then the price advantage will go away. Not a bad problem to have, but it means we'll have to shift our supply to other places like personal solar panels (hmm, does Musk sell those?)
Well, if/when such a battery exists it's likely the producers will use them to store energy at that time rather than offering the electricity at a negative price.
The whole reason of this negative pricing is that today, the grid can't store energy. When the tech becomes available, I don't see why the grid wouldn't use it.
Elon definitely sells solar panels as well. Tesla has already started providing a few battery packs to solar city [0] (which Elon helped his cousin's start) for storing energy from solar panels.
I am wondering where you are that the electrical power allows you to have real time pricing. I think in California some of the utilities have already banned people from using battery packs to help smooth out the grid while gaining money from it.
(For reference, the local fixed price default option is around 7.5c/kWh)
Granted, our latitude and climate doesn't offer the best location for solar generation so other things that hang off the grid aren't a huge problem for us at the moment.
Well remember this is the basic supply prices. ComEd tacks on another 4-5 cents in delivery charges and other supplemental crap. Then there are local/state taxes and etc.
And, sometimes, it isn't crazy cheap (especially when there's a cold snap in the south and everyone turns on their heat pumps)
Ahh, I did not realize that. That makes more sense than 3.5c/kWh. It is really interesting to look at this information and see how it changes from minute to minute.
It basically pushes the burden of averaging to the consumer -- except the consumer gains the advantage of being able to adjust their usage patterns to take advantage of the cost fluctuations.
"What might really suck though is if everyone has one of these in their homes, then the price advantage will go away. Not a bad problem to have,"
I like that because we could really use some more resiliency in our infrastructures. A legacy of the 20th-century love affair with centralization is that it involves mass-creating single points of failure. Having large-scale, distributed, significantly-sized, low-maintenance energy stores is good for all sorts of corner-case scenarios.
> What might really suck though is if everyone has one of these in their homes, then the price advantage will go away.
The price advantage may go away. But you would still benefit from it by overall more consistent/lower prices because inflexible (baseline) demand wouldn't drive up prices as much. And there are indirect benefits too. Baseline is mostly supplied by coal and nuclear. Needing less of those has health and environmental benefits which, when translated into $$$ are also non-negligible even if they're not really priced into the system.
If you flatten the demand peaks wouldn't the baseline go up? At the limit where demand fluctuation is taken care of by arbitrage central generation could be constant.
How much money do you want to sink into your power generation / storage / usage rig? You can increase the efficiency at which you do these things, sure, but that doesn't mean it will be economical.
Doing arbitrage on the power network by storing energy during off-period, and releasing it during high-period is a relatively old concept (eg. [0]). What I don't see happening is the price of this battery going low enough to make this kind of arbitrage profitable in a reasonable amount of time. The article does not mention the cost aspect of such an investment.
Germany along with a few other EU countries are currently high on renewable energy. As far as I know the most profitable way to utilize electric solar panels is to sell excessive energy back to the grid, not store it in batteries.
The problem is, selling it back to the grid only works when it's a fairly small fraction of the customer base that's doing it. We can't _all_ sell power back to the grid.
EDIT: Why the downvotes? This is a real issue... The current model of 'buy solar panels and pay for them by selling power back to the grid' will not scale forever...
That really isn't the current model. The current model is to buy solar panels today, thereby locking in your long-term electrical cost at the price of today's solar panels, with the expectation that conventional electricity will continue to rise, with a point 7-10 years in the future where you have "paid off" the panels, followed by 15 years of free/cheap power, avoiding the future high costs of electricity from a utility company, finally ending 25-30 years from now when you need a new system, but hopefully renewable technology will have greatly improved by then.
If the utility is paying a market rate (instead of an inflated rate to get people to invest in alternative energy), why couldn't we all sell power to the grid? Eventually if the home units get efficient enough, what would be the problem with power being supplied entirely peer-to-peer?
Granted, I think we're a very long way away from that, but I don't see anything wrong with the funding mechanism.
The market rate would just fall to near zero. The surplus from different homes would have very similar patterns. When it is sunny and bright out, everyone has surplus. At night, nobody does.
You are buying when everyone is buying and you are selling when everyone is selling.
That isn't even considering reliability. With wildly variable production, we will have to pay out of the ass for peaker plants to pick up the slack.
> The market rate would just fall to near zero. The surplus from different homes would have very similar patterns.
This assumes that all homes are using the same technology to generate power, but after the landrush to solar, rates (which are time variant) would incentivize new entrants to the "sell-to-the-grid" market to choose technologies which might be less average output per unit cost than solar, but which have different timing characteristics.
You are thinking from a large scale, profit-driven perspective.
The early adopters for this, at least in residences, will be people living off-grid, focused on self-sufficiency, and who are willing to take a financial hit to achieve that goal.
Not only will the batteries need to get cheaper, but the available arbitrage opportunity will need to account for the necessary upgrades to utility distribution systems to accommodate large amounts of distributed energy storage (DES). DES, particularly at high penetrations, generally violates the design assumptions of distribution protection systems and requires non-trivial upgrades to protective relaying and SCADA systems to maintain adequate real-time control.
I think it's worth giving Elon Musk the benefit of the doubt. It seems pretty likely that he'd consider these problems before moving forward with a product.
Losing power from snowstorms (well ice storms really) is quite common in New England and many family members have dropped $5k on propane generators. If you can bring this battery down to that price you will catch all those customers as well as have distributed off peak storage capacity. Right now the best way to store power is to pump water uphill, seriously.
'Pumping water uphill' will likely always be a very good way to store power at those scales. I would take a pretty spectacular number of batteries to match the stored energy potential of a small lake with a couple hundred feet of head.
Paper mills and other wood processing make for great instantaneous interruptible load.
In NZ one of the major electricity generating companies pays some major industrial customers for the ability to cut them off, enabling them to reallocate the power almost as if it were additional generation.
Aluminium smelters are good too, but you can't cut them off without warning, because it will break the arc-furnaces when the aluminium solidifies around the carbon electrodes.
Whenever Solar/Battery power comes up I like to link back to this [0]. There was a HN discussion about it [1] when the article in question [3] referenced that PDF.
My favorite quote is probably:
> To put this into perspective, who would have believed 10 years ago that traditional wire line telephone customers could economically “cut the cord?”
Solar panels would only affect the revenue of coupled utilities. Depending on the regulatory framework of the state, Decoupled utilities [0] would be unaffected by solar (and may even benefit if they supply the capital investment to install the solar)
The linked document by the Edison Electric Institute is titled "Disruptive Challenges" and it identifies distributed power generation (among other things) as a potential disruption in the industry. I assume the point is that if the electrical companies view this as a plausible future scenario, then we shouldn't rule it out.
This would be great for the situation were having in South Africa; were experiencing daily loadshedding at the moment as our only power utility basically, cannot meet demand.
The situation is set to continue for at least a year while the new coal power plant "Medupi" is being constructed - its more than 4 years behind schedule.
A battery that could be charged and then used to power your home during loadshedding could be a breakthrough solution as the costs for generators and solar are quite expensive. That being said not sure how much the Telsa "Home Battery" would be.
Any event, if its feasible it could really be a good solution. Im sure in the long run countries experiencing similar a situation could use this.
It's a phenomena in the UK that everyone makes tea using electric kettles during commercial breaks, which is magnified by the popularity of TV events such as sporting events to the point where the power grid is affected by how well the English team is faring in the game. The power service ends up having to predict the popularity of TV shows and how long sports games may last.
Brazil likely would also benefit. Our electricity production and grid are precarious at times and there are occasional rolling blackouts when things are mismanaged. A distributed great would help there.
The real blocker of going electric on everything is the capacity of rechargeable technologies and their lifetime, not some global conspiracy. Even the high price of batteries/capacitors might not be a problem if lifetime and capacity would be great. In that sense Musk might be onto something, but I think it takes a lot more than 20% improvement over current technologies for batteries to become feasible for storing electricity on large scale. If a smartphone could be done with a battery, that lasts a week and is not dead within a year in winter conditions, it probably would have been done allready.
A smartphone with a week of battery life is likely to be possible now. Just do this:
1) use the latest most efficient panel technology - let's say the latest Super AMOLED from Samsung
2) Use a very lower resolution such as 480x320 (also the initial resolution of the iPhone, which many thought looked "great" a few years ago)
3) Put a screen that's as small as possible on it - let's say 3.5" (you now...the "ideal" size that the iPhone used to have?)
4) Put the lowest power chip you can find in it (even if that means lowest performance - although a single-core 1 Ghz Cortex A7 should do the trick).
5) Put a relatively powerful (enough to handle that resolution easily), but very efficient GPU in it
6) Use other components that are also cutting edge in terms of power efficiency.
7) Put a 3,000-3,500mAh battery in it, even if it makes the phone 10-12mm thick (so like the Nokia Lumia 900 that many liked at the time for its "design", despite its thickness).
I would be surprised if all of this didn't lead to a week of battery life for the phone. The "problem" is this phone will be quite expensive unlocked (probably close to $300) due to its cutting edge/more efficient components, yet at the same time it will look like a $100 cheap phone in terms of "specs".
So where I'm going with this is that the market doesn't want such a phone even if it has a "1 week battery life". The market wants "PC-like performance", 2k resolutions and 5.5" screens more than they want "1 week battery life". And the other problem is that they want those specs to keep going up, and as long as those go up, battery life can't go up much either.
They optimize for performance and high specs rather than battery life. So if an OEM can choose between a 1080p panel with 30 percent less power consumption and a 2k panel with the same power consumption, they go for the 2k. And that's how our phones get stuck forever in the ~1 day battery life.
Smartphone batteries could easily last a week right now, with current technology. The reason they don't is because manufacturers prefer smaller size and lower weight to longer battery life, presumably because their customers do.
Size and weight are much less of a concern for fixed installation grid storage, of course.
> Smartphone batteries could easily last a week right now, with current technology.
Source? I always assumed the the main reason why modern cellphones' battery life is a lot worse than a few years ago was because of power-hungry processors and screens.
I don't think you really need a source for this. Current smartphone batteries last about a day in normal use. If you made it seven times larger, it would still be portable (just less so), and would now last a week. Increasing battery capacity by just adding more battery is trivial. What's hard is adding capacity without adding bulk or cost.
Yes, bulk is quite important factor too, especially on storing energy on large scale. Agreeing with the "can do a week of battery phone" on the other hand depends. The problem is that smart-phones have achieved lately their acceptable speeds with quad core (and up) processors. Resolution of screen makes less impact than the mere size of the area that has to be lit, but nobody wants to surf web through a peephole. E-ink would rescue if it could play videos and games fast. A lot of people want to do exactly that. And there are a lot of additional features we are used to keeping active (gps, wifi, ...). Turning these off will decrease the value of having a smartphone. Based on current battery sizes a week of battery would probably mean about 5 times the battery of phones now. That is not pocketable computer territory anymore.
In addition I would really like to have the phone component moved to watches (with at least 3 days battery) and leave all the rest for a pocketable computer to handle.
The Huawei Mate 2 has a 4000mah battery and I regularly get two days (30-40 hours) on it. It's very handy never having to worry about charging. It's thin and light (cheap feeling). As much at it sucks from crappy software (messed up version of Jelly Bean) and as much as I want to leave Google, no one else seems to be targeting even 20 hours of life. It's very frustrating.
The Mate 2 feels small enough that doubling the thickness would still result in an acceptable phone.
The financial implications of these threats are fairly evident. Start with the increased cost of supporting a network capable of managing and integrating distributed generation sources. Next, under most rate structures, add the decline in revenues attributed to revenues lost from sales foregone. These forces lead to increased revenues required from remaining customers … and sought through rate increases. The result of higher electricity prices and competitive threats will encourage a higher rate of DER additions, or will promote greater use of efficiency or demand-side solutions.
Increased uncertainty and risk will not be welcomed by investors, who will seek a higher return on investment and force defensive-minded investors to reduce exposure to the sector. These competitive and financial risks would likely erode credit quality. The decline in credit quality will lead to a higher cost of capital, putting further pressure on customer rates. Ultimately, capital availability will be reduced, and this will affect future investment plans. The cycle of decline has been previously witnessed in technology-disrupted sectors (such as telecommunications) and other deregulated industries (airlines).
Some companies have battery technology they believe is good for 10,000 [1] or even 16,000 [2] cycles until it reaches 80% of its initial capacity.
On the other hand, some batteries on the market show substantial capacity loss after just 300 cycles [3].
Needless to say, the product that lasts 50 times longer costs quite a bit more - and they're bigger and heavier to boot. For stationary power storage, you don't care if they're big and heavy, but for transport applications you do.
I think they'll build them so they make economic sense to customers. I think that would probably mean having more than 1000 cycles, but it could mean being really cheap, or some sort of lease/periodic replacement deal, or something like that.
The car tech has to worry about density and being charged really quickly. A big home battery should be able to make different tradeoffs including more cycles. Also, it lasts a lot longer if you're not discharging it all the way.
I suspect this market will be captured by folks not in homes, but in neighborhoods buying things like Sadoway's liquid metal batteries* and either participating in the bulk electricity market directly (fun fact: the markets run by New England ISO and NYISO are run as linear programming problems to minimize total cost over a bunch of supply curves bid in by suppliers and nuclear plants usually bid negative cost to make sure they get scheduled) or providing reliability-boosting service to utilities.
Seems odd to talk about "stationary batteries" as a separate product, as if a car weren't stationary most of its life. (but I suppose that changes in a future of sharing economies and self-driving cars)
> Seems odd to talk about "stationary batteries" as a separate product
Why? The constraints (in terms of size, cooling, wiring, weight, temperature changes, …) are completely different. A stationary battery is a separate product, competing in a completely different class and with very different constraints.
The cars are mostly stationary, but they're stationary in the wrong place during peak consumption hours: a workplace parking lot, not a garage connected to the grid.
I love it. The elephant in the room with electric cars has always been the power grid. It is simply not capable of sustaining the energy equal to the amount of gasoline distributed to gas stations. The last rough measure I've seen was the grid is about 1/4 what it needs to be to sustain electric cars.
Having batteries as energy cache spread out around the network is a great idea and will offset the need to build out more power lines.
It all really comes down to battery cost. If Tesla's gigafactory does what it says it will do, in seriously reducing cost per kwh, then a huge home storage market will open up naturally.
The projections do seem a bit heroic, though. People seem to have been predicting cost reductions in batteries for the last 15 years, but they don't seem to have come to fruition.
This makes the name of his company interesting homage to Nicola. Nicola competed with Edison and Edison eventually won out.
While Musk's plans aren't the same as Tesla's, the idea that an important part of the new structure of the modern electric grid bears his name is great.
Tesla made many people rich however. And was wealthy himself from time to time. He spent it all on more basic research and development. A true citizen of the world.
Please correct me if I am wrong in any of this, as I have a rudimentary knowledge of battery/capacitor/flywheel/Cox's timepiece tech at best. Li-ion make sense for supplying power for things which need Ah/kg high, but if you are not limited by mass, wouldn't maximizing aH/$ be the driving factor? Tesla has been making a massive push into li-ion fabrication and, as far as I can tell, not pursuing other energy storage mediums. Totally speculating here, but I would imagine a fly wheel, or even banks of lead-acid batteries, way out performing li-ion on total lifetime costs to the energy stored and discharged.
The original inventors of such technology are AC Propulsion [1] (coincidentally, the same company that Tesla licensed the early drivetrain for the roadster from). They referred to it as "vehicle-to-grid" (V2G) technology. Some interesting history in this idea - it's taken somebody like Elon Musk and a company like Tesla to start looking at implementing this technology in production/commodity markets.
Only for short periods of time. If you live in an area subject to natural disasters, you'd still want a generator (either diesel, propane, or natural gas) to get you enough power during extended outages to run a refrigerator, a TV, a few lights, and charge a phone or laptop. I was without power during Hurricane Hugo for almost 10 days. Cold showers suck, but what sucked more was not getting any news.
It is the furnace blower fan that is the essential thing to power. (assuming a natural gas/propane furnace) With that you can heat your house. If you can heat your house you can have running water. Without heat you will need to shut off the water and drain the pipes so they do not burst. At that point you have no heat and no water and you probably need to just leave.
Rural South Carolina. The apartment complex where I lived was apparently at the end of the transmission line, so we were one of the last in the area to get power back. My sister lived in Charleston at the time (where Hugo made landfall) and her VCR wasn't even blinking "12:00" when she returned after evacuating. Go figure.
I wonder if they should also market this to the whole house backup generator market? Those run 2,000-4,000 $ at least, I think.
I'd imagine a lot of houses would pay $1500 for a battery to operate their whole house during an outage.
Another product I'd like to see is a plug in battery to operate the sump pump for a few hours during an outage? Apparently a UPS can't handle the high load, and the battery backup ones you make require an expensive plumbing visit to install the special DC powered pump.
How long will that $1,500 battery power my house? It's still not possible to beat hydrocarbons in terms of energy density, and if you are looking to weather a multi-day outage, it's energy density you care about...
Further, when the power goes out you limit your consumption. With a connected home, running on battery power could widen the acceptable temperature range, run only one bulb in a multi-bulb array, or even disconnect certain outlets in a home.
Even cutting to 80%, you get an extra hour. 50%, and you've got 4. I am having a hard time finding refrigerator specifics, but around 1000KWh annually seems to be on the high side. This gives you 1.5 days on the 4.25KWh battery.
The added reliability should be a plus. And convenience in not having to keep it fueled up. Also you can use these in places where there's not enough ventilation to run a generator, and it's quieter.
It would be interesting to see the market statistics for installed generators. I bet propane and natural gas have a lot more of that market than gasoline and diesel.
it cannot help that GM has announced they will built the Chevrolet Bolt, a 200 mile range EV. Combined with other articles this car will start building in mid to late 2016.
In Spanish, these are 'voltio' and 'rayo'. The words you mention are not Spanish words.
However, it is true than in Latin American Spanish we do not perceive the difference between V and B. I guess the Aztecs and Incas did not have that in their own languages.
In Spain they do.
And in portuguese (the most similar language to Spanish) the difference is important as well.
Cool idea, but I think this is just a fallback plan or hedge for the new gigafactory. If oil prices stay low, it hurts the demand for electric cars. If we get driverless cars and more efficient ride sharing, people will be less inclined to own a car. But I'm sure musk has ideas to directly address those threats. He just doesn't want a $5b battery plant to be underutilized.
I am not all that sure I want it IN my house, and the garage for many homes is in the house. Yeah I know, people garage their cars but this is wholly different. Maybe outside the back in a small enclosed space, similar to an AC unit
I will be curious as to regulations for ventilation, wiring, and similar, are.
I think operating temperature is important, so I'd imagine outside or garage is a no go? (My garage gets down to 40F at night, not sure if that's typical).
But maybe with enough insulation you could put it anywhere?
Tesla cars are popular in northern European countries and I imagine these will work along the same lines: active heating of the battery. In the cars the capacity sacrifice is minimal and I imagine stationary batteries will be even better as (like you say) you can wrap them in a ton of insulation without having to worry too much about bulk and weight.
My main hope for vastly improved batteries (desperately needed) is that it'll be possible to combine a bunch of them and store the power for a small community (however it may be generated) thus decentralizing power supply. A localized grid would have major benefits imo
I think people under-estimate the capacity of car batteries, or over-estimate their home power usage. I used about 300 kWh last month, or about 10 kWh per day. A Model S has an 85 kWh battery. I could run my entire house on it for 4 days and still have 150 miles of driving range.
Utilities should be happy about this. One of their biggest problems is uneven load on the grid - low at night, too high during a heatwave - and this has the potential to make that problem a lot easier.
They should be, but they won't be. Because it makes people less dependent upon them.
If you bought one of these and enough solar panels you could go completely off-grid. Which the power companies desperately don't want. It's to the point where they're charging people for being hooked up at all, lest everyone think about putting in solar and only buying power when the sun isn't shining.
The utilities would be happy about this if they controlled it, but they won't because the capital expense would be way too high. They'll only be happy about it if they somehow are the only ones who have control and get to use it for free. Somehow I doubt that'll happen.
Hey, utilities are often run by public-spirited folk with no greedy agenda. They make decisions that are aimed to balance the needs of the many, which can appear to be against the wants of the few.
You're absolutely right! Some are. But some aren't, and some power companies are very scared and lashing out. There was an attempt in Arizona to get monthly connection fees of up to $100/mo if you have solar at all. Hawaii has blocked people from getting solar hooked up to the grid.
The problem is obvious, of course. At some point the only people left paying any kind of substantial monthly fees are those who can't afford solar, and those are likely the poorest. And then what happens is that there's a regressive tax. I get that you can't have that kind of bad outcome.
But at the same time, grid maintenance is fairly cheap and peak power generation is very expensive, which is why utilities will pay people to be able to turn off their A/C at peak times. This is quite literally where solar shines: the more A/C load there is the more likely you're getting good power out of solar.
If the utilities need to prevent a regressive tax situation then they need to change incentives to be more transparent rather than just flailing about. If peak power is expensive, make it easier for people to put solar up and get paid for it. If nighttime power is cheap, make it cheaper on the bill.
Power companies are basically complaining that arbitrage is hard. They're the ones who are in charge of their own business models, though, not me. So if they fail to adapt to the world as it stands, you'll forgive me for not feeling sympathy.
For the most part, 'they' is 'us'. We have to live with the results. My power company is the REC, and I could run for the board but I don't. Anyway its my neighbors trying their best to keep the power on for everybody.
You didn't mention issues of connecting to the local grid. There may be issues adding solar to your house, relative to the transformer and neighborhood substation. That $100 may be what it cost them to adapt. Likely its a tiny fraction of the cost of dealing with customers with unusual requirements.
> There may be issues adding solar to your house, relative to the transformer and neighborhood substation. That $100 may be what it cost them to adapt.
Almost assuredly no. There are laws in place and inspections which get done that prohibit anyone's inverters from being on when the power is off, this is to protect workers from getting shocked when a line SHOULD be down, but isn't. The inspection is simple and it's been done for many years for people who choose to install backup generators. Obviously those don't feed power back, but that leads into my next point.
If they can run 100 or 200 amp service to my house, surely they can afford a few dozen amps of power in the other direction. 100 amps * 220V = 22kW Many houses are wired for 200 amps so that's 44kW of power. Who is putting in 20kW to 40kW solar plants on their roof? A normal panel is between 200 and 400 watts. Which houses have 100 solar panels on them?
Further $100/mo times forever isn't reasonable if they only have a fixed capital cost to adapt. Again, they almost certainly don't unless everyone in the neighborhood is developing truly commercial amounts of solar and wind power. And if someone is breaking that threshold, fine I have no problems with them having to jump through hoops. They can afford it.
> For the most part, 'they' is 'us'.
It GREATLY depends on where you live. In rural areas it's a power co-op or whatever and I'm inclined to agree with just about everything you've said. But there are a lot of places where it's not a co-op and it's about someone turning a profit; for shareholders and everything.
> It's to the point where they're charging people for being hooked up at all
That's a completely reasonable thing to do... You're saying you would expect them to be ready to provide electrical service at a moment's notice, 24/7, but you should only pay for the actual power you use, but not for the standby capacity?
Yes, of course I agree it's reasonable. But it does serve to illustrate the point that utilities aren't necessarily happy about people being able to generate and store their own power. I'm refuting the idea that utilities will be happy about this, not trying to prove that they're evil bastards.
I'd also be happy to sign a contract whereby I'm only allowed X watts of draw and no more than Y watts of feed-in such that they don't need to have much standby capacity for me. But if I do that I want to get real-time pricing on power so that when it gets cheap or negative that I can charge batteries or make ice or whatever.
To me it kind-of feels like the utilities are pushing for a heads-they-win-tails-we-lose kind of situation where you get paid "base load" wholesale for your solar even if it's at peak times, but then have to pay retail for everything.
I know a guy who used to run a power company here in Houston (we've got a utility owned grid with many retailers making use of the "last mile" to sell power) and he said that $50/MWh ($0.05/kWh) was the normal rate but on very hot days it might go as high as $1500/MWh ($1.50/kWh) as everyone scrambles to buy enough wholesale power to meet the demand of their customers.
I'm not necessarily saying that I should get the $1.50/kWh that the utility is paying the marginal producer. But it doesn't feel exactly fair that someone who is peak-shaving their load and saving the utility company from buying power at $1.50/kWh and selling it at $0.08/kWh should also have to pay a connection fee for even having solar at all.
Utilities won't be happy about thus. They are already upset about having people with rooftop solar selling to the grid (taking their revenue); this will only make it worse.
It's not just maintenance. The system as a whole was architected to take advantage of the economies of scale you get when you assume that your customers remain consumers and you control the production. Nobody foresaw back then that each house could be a potential power plant. When you start to change that, you're still having to maintain the current infrastructure, which is steadily becoming obsolete, while also building new infrastructure to handle random power spikes and draws in arbitrary locations. You have to do this across the whole grid, everywhere in the country. This has the utilities very very nervous.
Absolutely. People have been installing batteries like these in their homes for quite a while now. Southern California Edison has been rejecting and even threatening to disconnect people with battery backups [0]. Their argument is that people with batteries can charge them during low load periods (normally night) and then push that energy back on to the grid at high load times (evening/morning) to make money. The article says Tesla is in talks with many utilities so hopefully they can get a good deal worked out.
This could really help wind and solar if these battery packs are cheap and utilities allow them to help regulate the power grid.
OT: For electric cars to succeed someone really needs to step-up and standardise the plug. It's ridiculous to have charging stations that are tied to a particular brand of cars.
SAE J1772 is a North American standard for electrical connectors for electric vehicles maintained by the Society of Automotive Engineers and has the formal title "SAE Surface Vehicle Recommended Practice J1772, SAE Electric Vehicle Conductive Charge Coupler”.[1] It covers the general physical, electrical, communication protocol, and performance requirements for the electric vehicle conductive charge system and coupler. The intent is to define a common electric vehicle conductive charging system architecture including operational requirements and the functional and dimensional requirements for the vehicle inlet and mating connector.(1)
The SAE J1772-2009 connector specification has been added to the international IEC 62196-2 standard (1)
The SAE J1772-2009 was adopted by the car manufacturers of post-2000 electric vehicles like the third generation of the Chevrolet Volt and Nissan Leaf as the early models. The connector became standard equipment on the US-market due to the availability of charging stations with that plug type in the nation's electric vehicle network (with the help of funding such as ChargePoint America program drawing grants from provisions of the American Recovery and Reinvestment Act).(1)
Thanks, I just found that Tesla has an adapter for it's cars to connect to SAE J17772 plugs: http://my.teslamotors.com/roadster/charging/j1772-mobile-con... . Too bad Tesla didn't standardise on that format so that other cars can benefit from their chargers.
You're confusing the issue. The J1772 standard for Level 1 (120V) and Level 2 (240V) charging is standard, and all electric cars use it. Tesla provides a J1772 adapter with every car they sell for at home and public charging.
The non-standard is the Level 4 direct DC charging, which has multiple competing standards. Tesla developed their own because there wasn't a standard when they launched Model S, and they wanted a system that allowed for free DC charging for their cars.
These batteries aren't going to power your home at night, nor should they as electricity rates at night are dirt cheap (comparatively) when people aren't at work, in factories and in bed sleeping.
These batteries are going to be performing grid marketplace arbitrage and some governments and utilities are providing amazing incentives to do so. (Currently the incentives require the batteries to be tied to solar.)
There are two pieces of your electricity bill (I'm simplifying here) 1) the electricity charge (EC) and 2) the transmission charge (TC). The EC is calculated by how many kWh you use during each (peak/off-peak) period of the day and the TC is calculated by your max grid demand during your largest 15 minutes for the month.
Tesla Batteries are not just about the batteries, the system calculates how to remove kWh demand from peak hours by pulling power from batteries and then recharging during off-peak hours. This covers the EC cost reduction.
To reduce TC costs the system calculates your peak load over the given month and tries to turn it from a "mountain range" (with many peaks) to a "platou". You pay your TC for the tallest mountain for the month. At first the system doesn't know that much about your usage profile and will just focus on the largest peak demand 15 minute intervals. Then over time it will learn more about your usage patterns and slowly platou your grid demand.
At the end of the day it is going to be much more cost effective and efficient to have a distributed grid with thousands of solar arrays and batteries than build out large billion dollar gas fired turbines or even wind turbines.