Electricity Costs From Different Sources

Electricity Costs From Different Sources
Electricity Costs From Different Sources

James Conca of Forbes tries to do a comparison of total life-cycles costs for each primary energy source over 60 years in comparing the different ways of generating electricity. The results are illustrated in the graph.

Conca differentiates between lifetime costs and other ways of comparing costs, specifically overnight costs and levelized costs:

"By life-cycle costs, I mean the total costs of building, operating, maintaining, fueling and decommissioning a thermal power plant, a solar array, a wind farm or hydroelectric dam over its life, that is, 15 years for a wind turbine, 40 years for a fossil fuel plant, 60 years for a nuclear plant, or 80 years for a large hydroelectric dam. Dividing those total costs by the amount of energy actually produced, not theoretically possible or installed capacity but actually produced, gives a life-cycle cost in ¢/kWhr. How we finance this cost is a totally different issue, one at which we generally fail as a society."

As the graph shows, hydro has the lowest costs at 3.3 cents per kWhr. This is due mainly to almost zero fuel costs and the 80-year life cycle of hydroelectric dams. Nuclear is second lowest with 3.5 cents, largely because of low fuel costs and the 60-year life expectancy of nuclear reactors. Coal is 4.1 cents, wind 4.3 cents, natural gas 5.2 cents and solar is the most expensive at 7.7 cents per kWhr.

Although fuel costs are free for wind and solar, their intensive capital costs, aggravated by the enormous amount of collection facilities that must be built, drive up their lifetime costs. It takes 9,500 windmills, for instance, to equal the life-cycle output of one AP1000 nuclear reactors, which is not the biggest reactor being built. Wind requires ten times the steel, concrete and copper per kWhr than any other energy source.

Natural gas plants are relatively cheap to built but are entirely dependent on future prices of natural gas, since fuel supplies make up 90 percent of the cost.

Conca believes that the market cannot handle these lifetime costs and that government investment and regulations should try to steer utility construction towards the energy sources that have the lowest lifetime costs. He recommends an investment pattern of 1/3 fossil fuels, 1/3 nuclear and 1/3 renewables.

Show commentsHide Comments

Related Articles