The perfectly green electricity grid sought by Joe Biden isn’t the end of the fight against global warming. It’s the beginning. Today, 40% of America’s electricity comes from carbon-free sources. The Democratic presidential candidate has made getting that to 100% by 2035 a centerpiece of his $2 trillion plan to address climate change and create jobs. Getting there would take an enormous expansion of solar and wind capacity in the U.S., backed by mass adoption of energy-storage technologies and hanging onto existing hydroelectric and nuclear plants. Policy experts question the 15-year timetable for eliminating emissions from the electrical system, which would indeed be an immense challenge. About a quarter of all U.S. emissions today come from electricity production, according to the U.S. Energy Information Administration. Even […]