Controversy is brewing as utilities consider “repowering” old coal-fired power plants across the US with natural gas. Several environmental groups initiated lawsuits to stop these plants from converting from coal to gas. Environmentalists want to shut the plants and replace the power they generate with renewables. Utilities argue this is not always possible, particularly in the short term.
This is a rather common bone of contention that often arises with regard to shutting nuclear plants, though in that case it’s often more difficult to replace the lost power because nuclear plants tend to have much greater power generation capacity than coal plants.
The case has been made in New York for example that “[d]ue to the current surplus in electricity capacity in New York State and New York City, even if Indian Point [2,000 MW nuclear plant] shuts down in 2015, there is no need to add further generation until 2020…” Much of that surplus, however, comes from hydro resources located in the north and western parts of the state, which would require new transmission lines to be constructed. That’s problematic because perhaps the only thing more contentious than building new transmission lines is constructing a new oil or gas pipeline.
Interestingly, part of the Indian Point replacement solution advocated by the NRDC includes repowering older plants with modern technology, but not all environmental groups agree on that strategy.
Much has been made of using natural gas as a bridge fuel until greater volumes of renewable energy can be brought online. From climate change and air quality perspectives, it appears repowering coal plants with natural gas makes sense. While it may be technically feasible to replace the generating capacity currently supplied by coal at the plants in question with renewable energy sources, it’s not clear that solution is economically viable without reducing grid reliability.
“The system requires a certain amount of megawatts and a certain amount of reserve margin to ensure that the system will be stable and reliable at all times,” said Gaier of NRG, which operates both renewable and fossil-fuel units. “The number of megawatts is simply not replaceable in the short term with renewables.” – As reported by National Geographic
Nobody wants to pay higher electricity bills or suffer more frequent power outages. While renewable energy costs – particularly for wind and solar – are dramatically decreasing, we are not yet able replace gas- or coal-fired generation capacity on an even basis without cost effective utility-scale energy storage solutions to balance intermittent loads. We are moving in that direction as energy storage costs decrease, technology advances and energy efficiency along with demand management becomes more widespread. As such, it would make more sense to direct the labor and legal costs aimed at blocking coal to gas switching toward these other measures.
