In reading all the articles, opinion pieces, and letters regarding the need to drastically cut greenhouse gas emissions to control climate change, it is clear to me that too few people really understand what is required to do this.
Obviously, we need to replace unclean power sources such as those burning gas or coal with environmentally friendly sources such as solar and wind power. People seem to think that that is the answer to the problem. It is not that simple.
For solar power it is obvious that the sun is not shining 24/7 and even when sunny, the amount of power generated varies not only with the brightness but also the angle it is hitting the solar panel. In other words, when someone claims that an array generates 1 kilowatt, this is the peak, not the average.
Even if it produced the peak power the whole time the sun was out, this would be only roughly one-third of the time (not considering cloudy/rainy days). The immediate reply from so many people is that the answer is wind power. When the sun isn’t shining get your power from the wind (ignoring the times when it is calm). If that is the answer, then why not use wind all the time and forget about solar?
The solution most often accepted is to use batteries charged by the solar array to provide power when the sun isn’t shining. Forgetting about when it is cloudy during the day, just the ability to provide power from late afternoon to the next morning would require the batteries to provide more than three times as much total power as would come directly from the solar panels.
So, the panels not only have to produce all the power in demand during the day but also the power to put that much charge into the batteries. In other words, they must produce almost four times the output most people talk about. That requires a lot of batteries which are environmentally bad to produce and dispose of. Of course, this can be said of solar panels, but the panels last for many more years than the batteries, which would have to be replaced every few years. These things don’t grow on trees.
There are other power/energy storage options, but they are not as simple as batteries, and it would take too long to cover them now.
Accepting that solar arrays should be an important part of our energy future, there are issues with where to install them. Replacing one large power plant would require on the order of 20,000 acres of panels. Cutting down forests to provide this acreage is a very negative thing to do. You are trading one environmental problem with another.
Putting them on already open fields is better, but still causes environment problems as well, for instance on many of these sites there is an issue with water runoff.
Simply putting them on rooftops and over parking lots is not the solution, as there is not even close to enough acreage. This pretty much leads to many large fields of arrays. To repeat, you don’t want to trade off one environmental problem with another.
People need to remember that we need this power all the time, not just when it is sunny, or the wind is blowing, especially when there may be several days in a row when it is not sunny. Where do we get our power then?
The only solution when we are counting on these power sources is a way of storing extra power when they are producing it and many think that the answer to this is to use batteries. The problem with this is the very large number of batteries required. How many days of heavy clouds or calm winds should we plan for? The other problem with this solution is the huge environmental impact in making batteries and disposing of them at the end of their life. There are other ways of storing the power, but the public doesn’t seem to be aware of them.
A major candidate for future environmentally friendly power is from nuclear. They could provide all the power we need 24/7. So many people are afraid of nuclear power, but they shouldn’t be if such power plants are properly designed, built and managed. Accidents such as those at Chernobyl and in Japan are caused by how they were managed or designed, not a concern for most plants.
The power plants today are based on designs from the 1950s (the basic plant design, even though the controls are new). The spent fuel problem would be solved if we simply opened Yucca Mountain as that is what it was designed for. There are new designs available, such as the small modular reactors and new ways of handling the spent fuel could solve the problems that concern most people.
Lee Armstrong lives in Leeds after retiring from a career of planning for and developing future technologies of many types.