It's explicitly addressed in the article. 10% of the water heaters purchased in a year would offset the dam. That 10% is 1 million out of 10 million. I guess

It's explicitly addressed in the article. 10% of the water heaters purchased in a year would offset the dam. That 10% is 1 million out of 10 million. I guess the lead time on water heaters is short enough to hand wave a yes.