Why Do We Still Article provided by Ohio Electric Cooperatives 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.
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 can’t we switch to all renewables?
Why is coal so much more reliable?
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.
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.”
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.
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.
“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.
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.
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