Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

By far the most common PV systems are single-junction monocrystalline silicon. These have had pretty decent ERoEI for many years (9–10 according to https://www.nrel.gov/docs/fy17osti/67901.pdf, but the energy required for PV modules has dropped precipitously since then) and don't use any rare-earth minerals.

Wind turbines have typically had even higher ERoEI (15–20 according to https://davidturver.substack.com/p/eroei-eroi-of-onshore-off...), and, while they do most commonly use rare earths, that's an engineering tradeoff rather than necessary; currently viable alternatives include switched-reluctance-machine generators (which just use conventional electrical steel, like transformers and relays) and other kinds of rare-earth-free generators: https://www.sciencedirect.com/science/article/pii/S030142071...



Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: