More than 500 oil- and gas-related firms have declared bankruptcy. The survivors are focusing on efficiency, and some plan a transition.
How will the world's most populous country and its worst polluter get there?
One expert says the state may need to improve its electric grid, while manufacturers bring down prices and pick up battery production.
Apple’s emissions from making its products accounted for three quarters of its carbon footprint last year.
Cleaner jet fuels and electric planes are still decades away, meaning Delta is focusing on carbon offsets.
Many suppliers of electrical power are facing the question of when to get to zero emissions, not if they need to get there.