One of the things I got out of this report (PDF) from Strata on land usage for various energy sources was that for the U. S. to get all of its energy from solar power would require an area roughly the size of Texas be devoted to the purpose. Wind power would require nearly twice as much or about half the state of Alaska.
“This study estimates that for solar to exclusively power the US it would require 16,393,234 acres, an area larger than West Virginia and Rhode Island combined,” much of which may be rooftop installations.
The numbers don’t add up. Or else they’re presuming that we start using substantially less power than we do now. When you multiply the number of MWh we presently use by the acres required for solar per MWh you get 174 million acres.
We’re getting ready to put solar on our motorhome to allow us to spend more time off-grid. I’ve done a lot of these calculations to see what we need. I’ve discovered the result is highly variable depending on your assumptions.
So I doubt there is a single answer – it really depends on assumptions.
Interesting that solar would only take about 3 1/2 times as much space as coal or gas according to this study. Looked at the details and don’t think they quite account for rooftop energy, but then that likely becomes much less significant if solar provided 100% of our energy.
Steve
It’s not like we are using Texas for anything better these days. We can carve out a little hole for Austin, and just cover the rest in solar panels.
The killer is the capacity factor. While in highly favored sites, such as the NW Scottish shore, wind capacity factors reach 35%, the usual value is under 9% (Texas PUCO). Solar is similar but smaller in general.
What this means is that solar and wind projects require “backup.” Of course the backup is providing anywhere from 65 to 90% of the total electricity.
For technical engineering reasons, the “backup” is almost alway natural gas-fueled gas turbines. And because the turbines must come on line in seconds, the turbines idle continuously when not in use the 10 to 35% of the time the solar/wind is generating power.
What this means, of course, is that solar/wind generate carbon dioxide continuously, and in amounts equal to fossil fuel power plants.
Right now, wind/solar are insignificant components of our electrical generating system, and the “backup” they need is provided by the excess capacity we have in nuclear, fossil fuel and hydro capacity. These sources of electricity are all under attack from environmentalists, and places like California and Germany are shutting them down. Those places are going back to preindustrial levels of power availability and, eventually, living standards. The Dark Ages are returning literally.
Solar/wind facilities produce electricity that is anywhere from 3 to 30 times as expensive as cheap nuclear and coal, and that does not include the cost of the “backup” facilities, which is always ignored.
The intermittency of wind/solar also introduces severe instabilities into electrical distribution networks once the fraction of wind/solar on the network exceeds about 4% (German data).
All-in-all, solar/wind are a victory for superstition and delusion. The connection between cheap, reliable electrical power and democracy and high living standards is firm. The future will not only be a Dark Age, it will be an age of slavery and poverty.
I discredit this article entirely on account of its surfeit of grammatical errors such as comma-spliced run-on sentences and lack of subject-verb agreement.
bob- They actually do shut down the back ups now sometimes.
https://www.technologyreview.com/s/526541/smart-wind-and-solar-power/
Steve