You don't have to be nearly as old as I to remember when it was considered very good for a thermal power plant to achieve an efficiency of 40 percent. The average efficiency of the existing U.S. fossil-fired plants is barely 30 percent, according to Siemens, and even gas-fired plants in combined cycle configurations typically achieve only 40 percent. So it's worth noting, for the record, that Siemens now has a gas-fired turbine that has set a world record of 60 percent, and that it's made its first sale of that turbine in the United States to a Florida utility, NextEra.
The turbine has just been demonstrated in a two-year trial run at an E.On plant in Irsching, Germany (above). The U.S. plant will have somewhat reduced physical dimensions and a slightly smaller output, reflecting the higher frequency of the U.S. grid. The first Florida turbine is expected to start operation in 2013.
The dramatically higher efficiencies of gas-fired plants, their correspondingly lower greenhouse gas emissions, and their relative cleanliness explain why natural gas is accounting for a fast-growing share of U.S. power production. Separately from the Florida transaction, Siemens also has just announced it will supply five advanced turbine plants to a North Carolina utility, to upgrade an existing plant.
Because gas is so attractive in terms of efficiency and environment, my guess is that U.S. production of unconventional gas will continue to grow, and that the industry will pay whatever it costs to satisfy local concerns about water and air pollution associated with fracking.