Energy Futures

A quick guide to alternative energy.

Ronald Bailey from the June 2009 issue

(Page 2 of 8)

Integrated gasification combined cycle (IGCC) plants mix coal with steam and oxygen to produce a synthetic gas. The gas is burned much like natural gas to fire a turbine and produce electricity. Waste heat from the gas turbine is then used to produce steam to run a steam turbine. This “combined cycle” of gas and steam power is more efficient than conventional coal-fired plants.

Technology invented: Coal gasification was invented by a Scottish engineer in 1792 and first licensed in the U.S. to what became the Baltimore Gas Company in 1813. As natural gas production became possible, coal gasification fell out of favor. New IGCC plants started operation in the U.S. in the 1990s.

Federal research dollars since 1976: See entry for supercritical pulverized coal.

Carbon emitted: 0.83 metric ton per megawatt-hour

Cost per plant without carbon capture: $3.4 billion

Estimated cost per plant with carbon capture in 2025: $3.7 billion to $4.6 billion

Production cost of a kilowatt-hour without carbon capture: 7.2 cents

Estimated production cost of a kilowatt-hour with carbon capture in 2025: 7.9 cents to 9.3 cents

Waste: This process produces the same solid wastes as other coal-fired plants but makes it easier to remove sulfur, particulates, and mercury from coal gas before combustion.

Advantage: Uses abundant coal and is more energy efficient than pulverization; makes it easier to capture carbon dioxide emissions.

Disadvantage: Capital costs are higher than those of pulverized coal plants.

Representative example: The $2.2 billion plant in Kemper County, Mississippi, will produce a maximum 582 megawatts by 2013.

Combustion turbine combined cycle

In a combined-cycle gas turbine power plant, the hot gases produced by burning natural gas drive a turbine. Heat recovered from the gas turbine is then used to produce steam, which powers a steam turbine generator and produces additional electric power.

Technology invented: The first gas turbine combined-cycle generation system was built by General Electric for the Oklahoma Gas and Electric Company at its Belle Isle Station in 1949.

Comments

Shannon Love|11.14.09 @ 1:16PM|#

This is a good article but it overlooks the most important cost factor. It doesn't matter how much it cost to generate a watt of electricity at the generation source, it only matters what it cost to receive a kilowatt of electricity at the point of consumption.

A good example of this would the real world cost of electricity from a portable diesel generator. You could calculate how much the generator cost and the average cost of diesel but that wouldn't tell you how much a kilowatt would cost if the generator was located in the wilds of Alaska and all the diesel had to be flown in. Likewise, the cost of hydroelectric power has to include the cost of transmission from were geology dictates the dam has to be to the point of consumption.

Since weather-dependent generation cannot produce power anything close to 24/7/365, the cost per kilowatt at the point of consumption has to include all cost of increased transmission, any energy storage systems and (far more realistically) the fossil fuel and nuclear plants that will always have to be running in the background to take up the slack with less than a half hour notice.

Electricity is not a luxury and it is not something we can do without. A modern economy is basically just a system for using electricity to turn dirt into useful things. We have to have electricity when and where we need all the time. Weather-dependent generation cannot provide that and has such it remain a toy for the foreseeable future.