Why do we STILL need coal?
Consumer-members of Ohio electric cooperatives understand the benefits of renewable energy sources like wind and solar — endless supplies that can’t be used up, with little to no carbon footprint. Why, then, can’t Buckeye Power, the generation cooperative that provides electricity to the 25 member cooperatives in the state, switch to all renewable resources? This month, we attempt to answer why coal must remain an important part of our energy generation resources.
Why can't we switch to all renewables?
In a word, reliability. Ryan Strom, manager of power delivery engineering services for Buckeye Power, says, “A lot of people don’t realize when they’re using electricity at home, there is a power plant actively running to support that.” Electricity is produced as you’re using it, not stored for when you need it.
The demand for electricity fluctuates minute by minute and hour by hour, depending on a variety of factors. A temperature above 90 F in the middle of the day creates the highest demand. A cool night with low humidity creates much less. A prolonged winter storm with below freezing temperatures drives up demand. Whatever the conditions, the supply of electricity must be able to match the demand.
“Reliability isn’t just about convenience,” says Kevin Zemanek, director of system operations.
While it’s important that the light comes on when you flip the switch, there are far bigger stakes. Factories depend on electricity being available to run their equipment and manufacture goods — their employees can count on coming to work and earning a paycheck for the day because the electricity will be on. Hospitals can perform surgeries and other medical procedures — the lights or the electric-powered life support equipment won’t fail just because it’s a day of high electricity demand. You can have safe food to eat because your refrigerator and freezer don’t just operate intermittently, when there’s enough electricity — they’re on all the time. “That’s because we use generation sources that are available to us all of the time, not just in ideal conditions,” Zemanek says.
Craig Grooms, Buckeye Power’s vice president of engineering and operations, explains the shortcomings of renewable sources. “Renewables are intermittent,” he says. “Resources show up when the wind’s blowing, but they’re not there when the wind is not blowing. The same is true for solar — when the sun’s shining, that resource is there.” When conditions are just right, those resources can produce at their maximum effectiveness. When night falls, when the sky is cloudy, or when the wind isn’t blowing, something else has to produce our energy.
Why is coal so much more reliable?
Coal provides “fuel security” — the assurance that fuel is always available to use. “Baseload resources provide power generation whenever you need it,” says Grooms. “That’s one attribute of a coal plant that we count on, not just for ourselves, but for the grid. So fuel security is about supplying energy to the grid when it needs it, and coal is a very stable, low-cost fuel that’s stored on-site.”
Natural gas is another resource that doesn’t depend on weather conditions, but there are limitations. Natural gas depends on the pipelines running smoothly, for one thing, but additionally, in very cold temperatures, the demand for natural gas rises quickly because many homes and businesses use it for heat. When the temperatures drop, those homes and businesses are using more of the available natural gas, which leaves less available for electricity generation.
What about batteries?
If energy were stored instead of produced as it was needed, intermittent resources could comprise a larger percentage of generation. But the technology doesn’t yet exist.
Large-scale battery storage is in its infancy. Grooms says, “A small amount is being used for utility-scale purposes, but it still provides a tiny, tiny amount of the overall energy to the grid.” The batteries that do exist hold only a few hours of supply. After that, additional energy is needed — enough to use right now plus enough to recharge the batteries. That wouldn’t be possible during a prolonged weather event.
Additionally, Grooms points out, “It’s very energy intensive to develop batteries, and there’s a lot of rare earth materials that go into batteries, which aren’t necessarily coming from the U.S. So you’re putting your supply chain reliability on other countries that may or may not be stable.”
Demand cannot exceed supply
Weather-related energy crises in California and Texas last summer and winter are a consequence of a situation in which demand exceeded supply. A combination of events — an extreme heat wave and prolonged windy conditions in California and bitterly cold temperatures and ice storms in Texas — drove up demand and kneecapped supply as production systems were knocked offline. Rolling blackouts were instituted to prevent collapse of the grid. The loss of power had devastating effects: The Houston Chronicle estimates that nearly 200 people lost their lives during the storm, most of them from hypothermia, and frozen pipes caused untold millions of dollars in property damage.
As renewable energy technology advances, more of these sources can be added to the grid and to Buckeye Power’s portfolio of generation. Buckeye Power remains committed to an all-of-the-above generation strategy, which includes renewable resources, natural gas, and the coal-fired Cardinal Power Plant. Above all, we remain committed to providing our consumer-members with safe, reliable, affordable electricity.