Energy is still cheapest when it comes from fossil fuels, excavated in the form of oil, coal, or natural gas. But as the price continues to come down on the unit cost of energy from solar and wind, countries that have traditionally been the biggest polluters of greenhouse gases are taking bigger steps toward clean energy.

This year China is planning to install 12,000 megawatts of solar capacity. That’s about what it takes to power all of New York City at the peak of summer. It’s also more in one year than the U.S. has installed since 1888, when a New Jersey chemist patented the world’s first solar cell.

China may be winning, yet other countries compete with impressive leaps. Japan and