Do coal plant closures spell disaster for the power grid?
A researcher at UT looks at the effect of wind and natural gas on Texas power.
For those looking for evidence of coal’s demise, look no further than East Texas, where Vistra Energy is shutting down its more than 40-year-old Monticello coal plant. At 1,800 megawatts, it is one the state’s largest power plants, and with other utilities eyeing their own coal operations, many more megawatts could be coming offline in the years ahead. Just a few years ago such developments might have set off fears of rolling blackouts in the summers ahead, when power demand skyrockets. But not this time around, explains Josh Rhodes, a research fellow at the Energy Institute at the University of Texas at Austin.
Q: You write about coal generation falling off in the years ahead. Is that setting the state up for power shortages and price spikes?
A: It’s hard for coal plants right now. Looking at the operating costs of most coal plants in Texas, they’re higher than the wholesale price, and it’s hard to see how they’re in the money. With all the gas we’ve unleashed through fracking and all of wind and solar being added, there’s a lot of pressure in the market to keep prices down. I don’t know if retiring these coal plants will do much to change that.
Q: Energy Secretary Rick Perry is one of a number of voices questioning whether coal plant closures could lead to a destabilization of the grid, with rolling blackouts like California felt in the early 2000s. Is that a possibility?
A: Theoretically, you could develop a problem if you don’t have enough resources to provide grid stabilization. But you have a system in place with generators standing by to come online quickly just in case another generator trips offline. There’s a market for those reserves, so as there are fewer generators that are able to supply those markets, prices will go up, and there will be more investment.
Q: You expect power generation from wind turbines to exceed that of coal plants by 2019. I know wind is growing, but that fast?
A: Wind has exceeded most people’s expectations. It’s been growing exceedingly strong for the past decade. Things like the (federal production tax credit) helped that. But we’ve also seen big firms are wanting it. With solar and wind, 99 percent of your cost is getting carbon and steel and silicon in the ground, and then you basically know how much these things are going to produce, so you can lock in your price for decades, and that’s really attractive to firms looking to buy energy. With gas or anything with a large fuel cost, you might only get a couple years’ guarantee.
Q: Can the grid handle that much wind and solar power, considering it’s dependent on the weather, which as we all know can be fickle?
A: Back in the early days, we thought wind and solar couldn’t be more than a couple percent of the power load, but now we have some days where it’s close to 50 percent. During the polar vortex, wind helped keep the grid going. That said, without massive energy storage, we couldn’t run the entire grid off wind and solar. But given how flexible natural gas is (coming online when wind and solar energy drops), the bar seems to keep growing.
Q: So is the day coming when there will be no more coal plants in Texas?
A: There’s no coal in the interconnection queue to be built. And all power plants have a shelf life, so if we don’t build any, eventually all of what we have will retire. One of the interesting things we’re seeing, if you look at the power plants we’re building these days, we’re not building big things anymore, we’re building smaller scale. Energy demand increase has been relatively flat lately, so it’s harder to justify a big project.