Anchorage's newest power plant, which began full operation on Jan. 31, combines an old idea with the latest hi-tech equipment.

The old idea is co-generation, which involves funneling waste heat from natural-gas turbines to heat water that spins steam turbines. The technique has been used for years, including in Anchorage.

Remarkably, 1981 was the last year Chugach fired up a new turbine of its own. That year, a steam turbine began sucking up waste heat from seven other natural-gas turbines at the Beluga River Power Plant across the inlet west of Anchorage, said Chugach spokeswoman Sarah Wiggers.

The new steam turbine is much more efficient. It uses 800-degree heat from three natural-gas turbines to crank out 39 megawatts of steam power. The old Beluga River steam turbine can crank out a bit more, 53 megawatts, but it requires the heat of seven natural-gas turbines.

Full story: New Anchorage power plant should eventually lead to savings