-- Wind and solar with natural gas backup produces electricity at about 200 grams of CO2 emissions / kWh. (windconcernsontario.ca)
The reason wind is so popular is because it requires natural gas backup and is driving a rapid conversion to natural gas in all sectors. (insteading.com)
In the film, activist Mark Lynas claims that because wind and solar power are intermittent, we must build 100 percent redundant natural gas backup plants for them. (dotearth.blogs.nytimes.com)