CHATTANOOGA (AP) — The nation's largest public utility plans to rely more on solar power in the future, according to proposals in a draft long-range power plan.

The Chattanooga Times Free Press reports the Tennessee Valley Authority expects to produce somewhere between 4 and 9 gigawatts of solar power over the next two decades while cutting power generated by burning coal. The amount depends on several factors, but renewable energy is predicted to increase and coal generation to decrease in all 30 approaches analyzed by TVA in its draft Integrated Resource Plan for 2040.

Hunter Hydas is a project manager for the resource plan and said during a public hearing Wednesday night in Chattanooga that the increase in solar is projected because it's becoming less expensive.

TVA serves about 10 million customers in parts of seven states.