Just days after the Obama administration announced it would implement rules to cut carbon emissions from existing power plants, Sen. Lisa Murkowski, R-Ak., bemoaned the collateral damage the so-called war on coal would have on the electrical grid.
“I am greatly concerned EPA’s rules – particularly in combination with one another – will result in a grid that is less stable and less reliable,” said Murkowski in an address to Congress. “The cumulative effect of federal regulations on baseload capacity – resources such as coal and nuclear which provide electricity on demand – must be examined and appreciated, not discounted or ignored.”
Sure, she’s saying, your rules might clean up the air and mitigate climate change, but it’s going to come at a cost: The grid might just collapse in the middle of the big basketball game.
Never mind that the relatively modest new rules won’t shut down coal altogether; that it’s still not clear how some of the biggest power plants in the West will be affected, because they are on tribal land; that climate change caused in part by coal burning is the biggest threat to grid stability; and that the general move away from coal in our energy mix has more to do with low natural gas prices than with regulations -- Murkowski has a point. When it comes to running a stable electrical grid, not much can beat coal. Fire up a 1,600 megawatt coal plant, and it puts out a steady stream of electricity that can keep the lights on and the iPhones charged in nearly one million homes, around the clock. If grid operators know that their customers will likely use more power the next day because it will be hot, for example, they can dispatch more coal power to compensate.
Wind or solar simply can’t replace coal. A wind farm puts out less than half the kilowatt hours of a coal plant of equal generating capacity, and the amount of power generated is determined not by grid operators, but by wind speed at any given time. Solar’s less manic than wind, but is still bipolar, blasting power into the grid in the middle of the day and going fully dormant at night. To smooth out the variability, utilities have to build fast-ramping natural gas plants, which are costly to build and operate. Hydropower has the potential to act as a baseload power source, but drought’s diminishing it in many places, and the amount of water put through the generators is often dictated by factors other than power demand.
Without building new nuclear power plants or doing some serious development of geothermal sources, there’s just no way to replace coal as a baseload power source. And maybe that’s okay. Last week, my colleague Judith Lewis Mernit suggested that it’s time we rethink the way utilities make money; I’d like to second that, and pair it with a suggested rethinking of the way we view and operate the grid: It’s time to let our baseload power fetish go.
California’s leading the way. State laws have pushed utilities to cut most of the coal-generated electricity from their portfolios, so that while the U.S. gets about 40 percent of its electricity from coal plants, California got just 7.5 percent in 2012 (and will drop to zero before long). The state lost a huge baseload power source when the San Onofre nuclear plant near San Diego was shut down in 2012. Meanwhile, solar and wind are being added to the portfolio at a rapid pace.
That has created the dreaded CAISO Duck. It is not a giant radioactive fowl, but the shape made by graphing demand that must be met daily by the California Independent System Operator, which runs most of the state’s grid. It looks like this.
The big dip in the middle of the day is not caused by everyone turning their gadgets off for an afternoon siesta, but by solar and wind going into the grid. Since solar — like customer demand — can’t be controlled by grid operators, it’s factored in as negative demand (also called “load”). The duck frightens grid operators because of the way the line climbs so steeply in the later afternoon, as solar output fades and air conditioners crank up, forcing them to find other power sources to meet the demand.
Rather than clambering for some of that ol’ fashioned, reliable baseload power, though, California is tackling the duck by searching for innovative ways to run the grid. I’ve written about some of these in the past, so check out the links for more details, but a fast recap:
• Storage is all the rage: Batteries, pumped hydro, train cars, you name it. The idea is to “charge” the storage medium when power generation is high but demand is low — in the duck’s belly on the aforementioned graph, for example. Then the power can be released when demand spikes and generation drops, like in the duck’s neck. Storage can also be used to smooth out wind’s intermittency. Last year, California regulators required utilities to install 1,325 MW of storage, which helped drive innovation in a field that has had trouble finding viable technology. Even Tesla, the electric car company, is getting into the game.
• A grid expert once told me that when utilities build natural gas peaker plants to smooth out dips in wind or solar energy production, it’s analogous to buying a big 4x4 to drive up into the mountains just a few times each year. It would make far more sense to simply rent the 4x4 when you need it, or for several families to go in on the car and share it. That’s sort of what three Western grid operators — CAISO, PacifiCorp and NV Energy — are doing with a newly formed energy imbalance market. Think of it as a giant energy generator sharing club, in which operators can buy power on an open market at short-time intervals. So instead of firing up their own natural gas peaker plant when they need to meet a demand spike, a grid operator can buy surplus wind power from Oregon, for example.
• Demand response and energy efficiency aren’t nearly as sexy as, say, a concentrated solar plant consisting of thousands of mirrors in the Mojave desert, but they’re far more significant. Demand response just means that the normal mode of balancing the grid, in which supply is adjusted to match demand, is reversed: Demand is adjusted to meet fluctuating supplies. The most obvious way to do this is to hike power prices when demand is normally the highest, incentivizing consumers to turn down their air conditioners and unplug their gadgets during those few hours, thus easing the steep climb of the CAISO duck’s “neck.” By turning our air conditioners off, they become de facto distributed generators, “adding” power back into the grid at critical times.
So while Murkowski and friends are stuck in their fossil-fueled, baseload past, a handful of grid operators in the West are moving into the future. It’s time for the rest of the West to get on board.
Jonathan Thompson is a senior editor at High Country News. He is based in Durango, Colorado, and tweets @jonnypeace.