Fifteen terawatts. That's 150 billion 100-watt light bulbs burning 24/7 for a year. Which is how much energy humanity now uses annually.
Most of it is dirty. Burning coal sullies the atmosphere and leaves toxic ash mountains. Natural gas is better for CO2 but not enough to halt global warming. So the hope of man who combat climate change is that alternative energy—electricity from sunshine, wind or low-carbon nuclear—can begin to replace fossil fuels.
Unfortunately, the additional renewables are not helping cut back on fossil fuels much. That's according to an analysis published in the journal Nature Climate Change. In fact, over the last 50 years, adding a unit of alternative energy to the grid displaced a mere one tenth of a unit of fossil fuel-fired power. And those alternative energy additions have been small.
In other words, to get away from fossil fuels requires not just expanding alternatives but also discouraging the use of coal, oil and natural gas. Carbon tax anyone?
[The above text is a transcript of this podcast.]