India's addicted to coal. But for how much longer?: Reporter's Notebook

Prime Minister Narendra Modi said he'll only commit to net-zero by 2070.

Sapna has a smiling face and a bright red sari. She stands on the doorstep of the small hut she calls home, her daughter huddled slightly behind her, and ushers us inside.

The courtyard is only about 15 feet across. Washing hangs overhead, and some plants sit wilting in the heat next to the door of a small living area.

She takes a large plastic container full of water and pours it all on the floor in front of us. Immediately it starts to steam. And then I realize what Sundeep is trying to tell me: The floor we're standing on is hot from the mine beneath our feet.

Coal burns underground for 24 hours a day, and its heat has made the floors of these homes hot to the touch. In a country where summer temperatures can exceed 120 degrees Fahrenheit, Sundeep's floor is almost boiling hot. I bend down to touch it, and it's genuinely almost scalding.