This decade, the world's most valuable companies (all of them American) will be putting their money where their mouth is.

The pandemic set oil production back two years while investments in alternative energy grew, leading some forecasters to predict an earlier arrival of peak oil.

Now that cities can build solar fields for no more money than coal plants, advances will accelerate.

How solar energy managed to thrive in a tumultuous year full of challenges.

America installed 4.5 GW of utility-scale solar in 2019, bringing the country's cumulative capacity to 29 GW.