A landfill has become a new source of energy for two Missouri state prisons and for the capital city of Columbia.

Here's how it works. Decaying garbage at a Jefferson City landfill makes methane gas naturally, which powers a generating plant that provides power for the city of Columbia and heats the water for two area prisons.

The plant saves taxpayer dollars and reduces the need for natural gas.

"That landfill's been in operation since 1978 and it's nice to see that the methane that's been generated can now be captured and reused in such an efficient and innovative way," explained Republic Services' Kevin Wallbridge.

The annual energy savings is estimated at $400,000.