3 ms·
> Those wind turbines are upwards of 10 MW each Assuming a 35% capacity factor (taken from land-based wind turbines, offshore should be higher), that's 84MWh/d
by danans 5y ago
> Those wind turbines are upwards of 10 MW each
Assuming a 35% capacity factor (taken from land-based wind turbines, offshore should be higher), that's 84MWh/day.
The average California single family home uses 20 kWh per day, which means that that capacity factor this turbine could power about 4200 homes per day.
For comparison, a 10 megawatt solar project, assuming a standard 20% solar panel efficiency and one kilowatt per square meter insolation, would require a five square kilometer solar array. The capacity factor of PV solar is inherently limited by sunlight hours, but it is around 28% in California.
If offshore wind is available 24 hours at such a huge scale, it could change the renewable energy mix considerably.
In that world the biggest advantage of solar would be lower maintenance costs and greater visibility at smaller scale (for example, coupled with batteries to form micro grids).
- philipkglass 5y agoI think that you made a mistake with the solar farm area comparison. 10 megawatts per square kilometer (annualized, already accounts for night time and clouds) is a decent rule of thumb for solar farms. So 84 MWh/day (3.5 MW) would take 0.35 km^2 of solar farm. If solar farms were completely tiled over with 20% efficient panels achieving 28% capacity factor, 3.5 MW would occupy only 0.0625 km^2. But offshore wind still has advantages in that it doesn't occupy on-shore real estate and can supply power at night without batteries.
- danans 5y ago> 10 megawatts per square kilometer (annualized, already accounts for night time and clouds) is a decent rule of thumb for solar farms. Oops, you're absolutely right, I didn't square the power, and it messed up the answer by a factor of 1000!
- kumarvvr 5y agoIn India, a 10 MW installed capacity solar plant occupies 52 acres, about .25 sq.km You 5 sq.km figure, even for Cali is suspiciously high. Maybe you missed a decimal? Edit https://en.m.wikipedia.org/wiki/Topaz_Solar_Farm https://en.m.wikipedia.org/wiki/Topaz_Solar_Farm Topaz farm is 550 MW on 19 square Km.
- dtgriscom 5y agoUnit problem: such a turbine could power about 4200 homes; no "per day" involved.
- danans 5y agoI should have clarified: the energy produced by one such turbine in a day could provide for the 1 day electrical energy needs of 4200 CA homes.
- kolinko 5y ago5 sq km is 5 million square meters, so 5 sq km would give 1GW according to your assumptions :)
- guerby 5y agoOffshore capacity factor can be very high: https://www.equinor.com/en/news/20210323-hywind-scotland-uk-best-performing-offshore-wind-farm.html https://www.equinor.com/en/news/20210323-hywind-scotland-uk-... "With an average capacity factor of 57.1% in the twelve month period to March 2020, the floating offshore wind farm set a new record in the UK." In France 2019 nuclear capacity factor was 68.7% (379.5 TWh produced out of 63.1 GW installed capacity). Edit: nice sortable table here https://energynumbers.info/uk-offshore-wind-capacity-factors https://energynumbers.info/uk-offshore-wind-capacity-factors
- danans 5y agoThanks for the corrections on solar output! I was off by a factor of 1000 because I didn't square from square meters to square km.