Ask families in Germany and the UK what happens when more and more supposedly “cheap” solar and wind power is added to the national power mix, and they can tell you by looking at their utility bills: It gets far more expensive.
The idea that power should get cheaper as we get more green energy is only true if we exclusively used electricity when the sun is shining and the wind is blowing.
But modern societies need power around the clock. When there is no sun and wind, green energy needs plenty of backup, often powered by fossil fuels. What this means is that we pay for not one but two power systems.
And as the backup fossil fuel power sources are used less, they need to earn their capital costs back in fewer hours, leading to even more expensive power.
This means real energy costs of solar and wind are far higher. One study looking at China showed that the real cost of solar power on average turns out to be twice as high as coal, while a peer-reviewed study of Germany and Texas shows solar and wind are many times more expensive than fossil fuels.
Hellbound and Down 