We've been hearing for some time now how the only answer to save the planet was to switch all of our electricity over to renewables, ditching coal, oil, natural gas, and nuclear power. Most of those making such claims obviously haven't done the math, haven't figured out that it is impossible for all of our energy needs to be met with renewables unless they are willing to allow widespread ecological damage that will be required in order to realize the 'dream' of renewable energy. An example I used in one of the Disqus comment threads laid out the problem, running a rough calculation of what it would take to replace a single nuclear power plant, specifically the Seabrook Nuclear Plant in Seabrook, NH with solar.
Seabrook is a 1300MW plant. The grounds take up about a square mile of land on the New Hampshire seacoast. A 1KW solar panel is about 18 square feet in area. It would take 1,300,000 panels to equal the output of Seabrook. But that would only be the instantaneous output.
To provide the equivalent of a Seabrook 24 hours a day, 7 days a week would require many times that number, assuming that sufficient power storage capability existed. For the purposes of this exercise we will assume that it is close to the equinox, so there would be 12 hours of sunlight and 12 hours of darkness. We can assume that maximum effective generation takes place for about 4 hours every day, but to be overly generous, we'll assume 6 hours. To provide enough power for 24 hours you would need 4 times as many solar panels since you'll need to generate a full 24 hours worth of electricity in only 6 hours, with one-fourth for immediate use and the other three-fourths being stored for use later in the day when there is little or no sunlight. So that increases the number of panels needed by a factor of 4 which brings the total needed to 5,200,000. But wait, there's more!
You also have to take into account that it isn't always sunny during daylight hours, so there will be a less than 100% sunlight available during the 6 peak hours. Again, we'll be generous and assume that any deficit will be only 30%. That means there will need to be 30% more panels to make up the deficit. That takes us to 6,760,000 panels. There are still a lot of other factors that would need to be taken into account, but I'd need a bigger blog to address even a few of them, so we'll go with the 6,760,000 panels for the rest of our calculations.
Since each panel is 18 square feet in size, that means the total area of the solar array will be 121,680,000 square feet in size. That equates to 4.36 square miles, and that assumes all of the panels are built with no gaps between panels. Since that isn't practical, it's more likely that there will need to be space between rows of panels to allow for maintenance, rain and snow run off, as well as thermal expansion. So let us assume that there will be one panel's length between rows. That doubles the area covered to 8.72 square miles. So in order to replace a Seabrook, we'll need almost 9 times the land area, and that's assuming almost ideal conditions. Seeing as we are almost halfway between the equator and the North Pole, the useful amount of sunlight available to the solar arrays will be less than what I've calculated here. The area needed to provide adequate electricity equivalent to the Seabrook nuclear power plant, at least during the winter months, is likely to be double of what I've already calculated, meaning 17.44 square miles. Now multiply that by the number of Seabrook power plant equivalents – nuclear, coal, and natural gas plants, and you'll see the problem.
There's also the matter of severe weather that can damage or destroy large portions of the solar arrays.
Then there's wind, something I've always found intriguing, but also troubling considering the large amounts of land they require, the documented health problems associated with them, and their deleterious effect on birds and bats.
Keep in mind that my calculations above are merely back-of-the-envelope estimations. I know I've left out a number of factors that can affect the numbers. But when the We-Can-Replace-All-Of-Our-Energy-Needs-With-Renewable-Energy believers choose to ignore major factors, including the vastly increased demand for electricity that is supposed to replace fossil fuels, I have to get my three cents worth in. (Where do they think all of the electricity needed to charge all of those wonderful electric vehicles is going to come from?)
Then there's this:
'Nuff said.
