Table 4. Estimates of cost of energy per kilowatthour by source.

Source

Cost per kilowatthour in cents

Coal

2 - 5

Natural gas

2.8 – 12

Landfill gas

2.9 – 3.6

Wind

3.5 - 5

Manure

3.7 – 5.4

Geothermal

4.5 – 7.5

Solar thermal (large array)

16

Photovoltaic (solar farms)

                      (roof tops)

24

19 – 40

From various sources.