Here’s a depressing fact about energy use in the United States. According to the government’s current projections, we get about 80 percent of our energy from fossil fuels now. And in 20 years, we’ll still be getting 80 percent of our energy from fossil fuels.

Yes, we’ll be adding more renewable energy to the mix, and we’ll even stop building new coal plants, according to the Energy Department projections. But demand for energy is going to grow at such a pace that the renewables we bring on line won’t change our energy mix. They’ll just help us keep up with growth. And unless we change that mix, we won’t make any progress on climate change or energy security. We