3 ms·
>Renewables scale just fine An average 3 MW wind turbine will generate about 6 GWh of energy per year. It's estimated that wind farms can produce around 4 MW p
by Mirioron 8y ago
>Renewables scale just fine
An average 3 MW wind turbine will generate about 6 GWh of energy per year. It's estimated that wind farms can produce around 4 MW per square kilometer, so let's go with around 8 GWh per sqkm.
In 2014 the UK used about 302 TWh of electricity (out of a total energy usage of 2249 TWh). To match the 302 TWh of electricity with these wind turbines you'd need wind farms covering 37,750 square kilometers. To cover the UK's total energy usage, you'd need an area greater than the surface area of the UK to be covered in wind farms.
These are back of the envelope calculations, but they do point out the problem rather well.
- pfdietz 8y agoSolar is beating wind in new capacity auctions in Germany now, and I expect it will also do so in the UK soon enough. You'll still want some wind for diversity of sources, but solar has higher power/area. Europe in general will have trouble in a solar-powered future, though. Energy intensive industry will migrate to the cheap energy closer to the equator.
- Mirioron 8y agoSure, but the amount of power you need to generate per area needs to be multiple orders of magnitude better than wind for this to be a viable option. At least you can build wind farms in the sea.
- adrianN 8y agoSolar panels have about 150W per square meter.
- Mirioron 8y agoCan you provide a source on that? I find it (slightly) difficult to believe, because you want your solar panels to track the sun. This means that a 1 sqm solar panel needs much more space to operate depending on how far north you are. I'm not saying it's not possible, but I'd love to read more about it!
- adrianN 8y agoNormal commercial solar panels have around 175 Watts/sqm peak output. You're right that you rarely get that peak output, but it's still a lot better than the numbers you gave for wind turbines. They also have the benefit that you can put them on roofs, i.e. space that isn't used for anything else.
- _Tev 8y agoBut that's the problem with renewables - no one talks about utilization / MWh produced per year. Instead you quote "peak output" and hope nobody notices it's not a valid argument. I heard about 0.12* being utilization factor for Czechia (right next to Germany), but you can't really google this as everyone spams about installed capacity, peak output and other useless figures. * that would mean 17.5MW/sq km. So yes, better than GP figure. No, still not usable (improvement of only factor 4.5). EDIT: Quick calculation based on numbers here: https://en.m.wikipedia.org/wiki/Solar_power_in_Germany#/media/File%3ASolar-energy-factsheet-germany.jpg https://en.m.wikipedia.org/wiki/Solar_power_in_Germany#/medi... gives me solar utilization factor of 9.5 for Germany in 2016.
- jnsaff2 8y agoUK is 242,495 km2 Also lots of wind parks are off shore where there’s less vegetation and hills to slow down wind.
- Mirioron 8y ago>UK is 242,495 km2 And 2249 TWh / 8 GWh = 281,125 >Also lots of wind parks are off shore where there’s less vegetation and hills to slow down wind. They're more expensive to construct and tear down after. They do generate more power, on average, but in these calculations with average it would only give you a ~20% advantage.