Energy Storage Will Soon Replace Simple Cycle Combustion Turbine Peaker Plants. Power grids need extra generating capacity to work properly. For example, about 20 percent of New York Stateâs generation fleet runs less than 250 hours a year. Because they donât run much, âpeaker plantsâ are by design the cheapest and least efficient fossil generators.
The largest source of carbon dioxide (CO2) emissions are currently  from electric generation through the combustion of fossil fuels.  Particularly the burning of coal is mos â¦ t pollutive, as compared to  oil or natural gas generation.
Fossil fuel combustion/use. The largest human source of carbon dioxide emissions is from the combustion of fossil fuels. This produces 87% of human carbon dioxide emissions. Burning these fuels releases energy which is most commonly turned into heat, electricity or power for transportation.