Fifty Shades of Green?
On this St. Patrick's Day, when even the beer is green, it may be appropriate to think about all the claims about which energy sources are green.
Most people view renewable energy sources, such as solar and wind power, as green, and fossil fuel sources, especially coal, as not green. The reasons are clear. Coal produces particulates, which cause significant health and other problems locally, and also generate greenhouse gases, which have global impacts. The sun and the wind are "natural" and, in themselves, benign. Some people think that means green, but it isn't that simple.
People tend to be uncertain how to rank nuclear in this regard. On the one hand, they know it doesn't produce the particulates or greenhouse gases that coal and other fossil fuels produce. On these grounds, pro-nuclear people claim that nuclear power is green. On the other hand, it produces nuclear waste, which is not natural and lasts a long time. On these grounds, anti-nuclear people claim that nuclear power isn't green.
The truth is that nothing is perfectly green.
As many experts have pointed out, we can't extract large quantities of sun or wind or hydropower without building solar panels or windmills or dams. Solar panels, windmills and dams require materials. The materials have to be mined and processed. These steps cause environmental impacts, just like mining coal or uranium, or anything else. Some of the materials and processes generate toxic by-products.
But because the wind and the sun are diffuse, they tend to require more structures per unit of energy produced than more concentrated forms of energy, like fossil fuels and nuclear power. And that means more materials and more mining and processing. And more land use.
In truth, there are shades of green. I don't know if there are 50. There are probably more. The designation "green energy" is, unfortunately, an oversimplification that has caught people's imaginations. However, it greatly oversimplifies the situation. Different energy sources use different materials, in different quantities, and generate different kinds of pollution in different places. What looks green at point of use has negative environmental impacts elsewhere.
We seem to have a hard time acknowledging that human population and modern lifestyles have an inevitable impact on the environment. There are measures we can take to reduce the impact, but we shouldn't fool ourselves into thinking that the green label we have bestowed on some energy sources really solves the problem.
So, maybe nothing is truly green today except the beer. Sorry, Saint Pat!