As the peak of summer arrives, Americans are turning up their air conditioners.
But this added demand for electricity can greatly tax power grids. And in some states, it could pose real problems.
As North American Electric Reliability Corp. (NERC) CEO Jim Robb recently explained, backup power reserves in Texas are stretched to the limit, and there’s “no way in hell they can keep the lights on.” Robb added that natural gas shortages in New England are also straining power supplies, and the regional grid operator “constantly finds another rabbit to pull out of his hat to keep the lights on.”
It’s not just Texas and New England, though. California’s power grid is also facing problems, thanks to a new emphasis on solar power at a time of limited natural gas supplies.
Why the challenges in delivering electricity? Texas offers a good example.
The Lone Star State has been closing coal-fired power plants in recent years – and retired 5,000 megawatts of coal-fired generation in 2018 alone.
At the same time, Texas has invested heavily in wind turbines.
In 2017, wind turbines produced roughly 14% of state electricity.
The problem for Texas, however, is that wind production has proven to be erratic.
In March, for example, state electricity demand peaked during a stretch of unexpectedly cold weather. But needed wind generation simply didn’t materialize, and Texas wind turbines delivered only 16% of their average output. As a result, spot electricity prices in northern Texas jumped 700% during a period of high demand.
This heavily subsidized wind power has now undercut the value of essential coal plants. And losing so much coal capacity has drastically trimmed Texas’ reserve power margin.
NERC reports that Texas has a thin reserve margin of 8.5% to handle peak electricity demand this summer, significantly below the target level of 13.75%. This means unexpectedly high heat and high demand, or the loss of generating capacity, could push the state’s grid into an emergency.
New England and California face a different problem.
Both regions are relying heavily on natural gas-fired power generation. But ISO New England is flagging “unacceptable fuel security risks” for the region that stem from a lack of sufficient natural gas supplies. However, New England isn’t currently planning to build new gas pipelines to increase fuel delivery.
Similarly, California’s natural gas supplies have fallen in the wake of a 2015 leak at its Aliso Canyon storage facility. Although the state needs more gas pipelines to ensure back-up fuel for power plants, policymakers remain focused on expanding the state’s solar capacity.
However, a study by Wood Mackenzie found that California’s changing electricity profile, combined with insufficient natural gas capacity, could lead to power shortages after sunset – when solar panels can’t deliver power.
In order to plug such holes, California will need to invest at least $12 billion in nearly 15,000 megawatts of four-hour battery storage.
What all of this tells us is that a rapid jump into renewable energy, along with a reliance on overstretched natural gas pipelines, invites unexpected consequences.
Coal and nuclear power have been demonized over the past decade, even though they generate large volumes of non-stop, reliable electricity.
Replacing them with less reliable alternatives poses serious challenges to grid reliability – and these are challenges that states must consider carefully.
See the article here.
- On July 29, 2019