The Northwest has set goals to use more renewable energy over the next 15 years, but the existing power delivery system wasn’t set up for getting variable wind and solar power to your house efficiently.
Power grid managers have to keep a steady flow of juice in the power lines at all times to avoid blackouts and grid damage, so they need a back-up plan for when the wind changes. Maybe even 5 back-up plans… These aren’t all be “smart grid” per se, but they are smarter ways of running the grid to accommodate new forms of renewable energy (wind, solar, geothermal) as well as the old reliables (hydro, coal and natural gas):
1. Wind forecasting
Scientists at the Pacific Northwest National Lab are putting some extra effort into predicting how much the wind will blow so that power managers will have a better idea of how much wind power to expect.
That way, grid operators can be ready adjust other power sources – like hydropower and/or gas-fired power plants – to balance wind variation. In fact, Bonneville Power Administration has a way for you to see for yourself how much the wind is blowing.
2. Shorter power scheduling:
15 Northwest utilities are moving to intra-hour scheduling – that’s buying, selling and managing power in 30-minute intervals instead of every hour. It’s a big step toward accommodating the hard-to-predict changes in renewable power supply – especially wind energy. Renewable energy advocates say it’s good for overall grid efficiency, too.
Bonneville Power Administration spokesman Michael Milstein said one major effect of shorter scheduling is that his agency, and other utilities that are in charge of keeping the grid balanced, won’t have to keep as much power in reserve just in case the wind dies down:
“What happens is a wind producer will say we’re going to generate 100 megawatts over the next hour, and then the wind changes. Because power’s always been bought hour to hour, they’re screwed and, in this case, BPA gets stuck with that problem in terms of balancing what actually comes from what was scheduled. If the wind only produces 50 megawatts, BPA has to find 50 more megawatts to make up for the difference.”
Scheduling power in 30-minute increments cuts the margin of error significantly, though the Federal Energy Regulatory Commission is targeting 15-minute scheduling for power systems nationwide.
4. More power trading:
Power managers in the Northwest are looking more and more toward pooling their power generation and transmission capacity to balance the ups and downs in smaller sections of the Northwest grid. A so-called “power imbalance market” could spread those swings across a larger geographic space and make renewable energy easier to manage.
Jon Kaake, CEO of the independent grid analyst group Columbia Grid, explained that there are several utilities in charge of balancing power across sections of the Northwest grid. If they all talked to each other more often and traded their extra power or extra transmission, it would give everyone more options for balancing out unexpected swings in the power supply. Kaake said a new method of checking the entire system every five minutes and adjusting for extra power and transmission would be a good substitute for the more efficient transmission systems other regions are using to create a competitive energy market with one regional grid operator.
But with new wind, solar, geothermal and biomass projects all coming online in the near future, he said:
“Ultimately, you’re not going to get around the need for more wires in the air. The problem is if we’re looking 10 years out, it may take 10 years or more to construct the line. The big issue is to try to use whatever’s left as effectively and efficiently as possible.”
3. More transmission options:
The more ways there are to get power from its source to the end user, the easier it is to maintain a steady supply at all times. If one route is full and the wind suddenly picks up, having another path for it to follow will keep the system running. Similarly, widening bottlenecks in the system, such as the one on the line connecting California and Oregon, allows more power to use that route at any given time.
Bonneville Power Administration is building four new transmission lines, most of which are designed to accommodate wind power, according to spokesman Michael Milstein:
- The McNary-John Day line between the McNary and John Day dams on the Columbia River.
- The Central Ferry Lower Monumental line in southeast Washington near the Snake River.
- The Big Eddy Knight line from The Dalles to Goldendale, Wash., on the east end of the Columbia River Gorge (controversial because it has scenic impacts).
- The I-5 Corridor Reinforcement Project through the Vancouver, Wash., area would equip the grid for growing summertime power demands. It’s the most controversial and the farthest from completion.
BPA, PacifiCorp and Portland General Electric just finished an upgrade to the California-Oregon Intertie. There’s a looming question of whether (when?) to upgrade other large transmission interties that connect the Northwest with Canada, Montana and California and are jointly owned by multiple utilities. Those upgrades could help surplus power find markets outside the Northwest in the springtime when there’s lots of hydropower.
BPA is also testing out some new realtime monitoring equipment called synchrophasors that will give power managers a much clearer, real-time picture of where power is going so they find better transmission routes if possible. Milstein said under the old system it’s like power managers are driving down the freeway with their eyes closed half the time. With this new technology, they can open their eyes every two to four seconds and see what’s happening in the power system.
5. Smart grid technology:
This is the more exciting (and controversial) stuff that you typically hear about in conversations about managing the grid for more renewable energy and energy efficiency. And for the most part it’s still in the experimental phase in the Northwest. It employs a two-way communication system to allow grid managers to use homes and buildings for energy storage and efficiency.
It can involve using hot water heaters or industrial refrigerators to absorb surplus power, dialing down home thermostats slightly to reduce power use during peak hours, or sending signals to home appliances to turn on when power is cheap and off when it’s in high demand. These options all offer grid managers some cushioning for when the wind picks up or drops off. And they’re all being tested in little pockets of power users around the Northwest.
A $178 million grant from the U.S. Department of Energy launched the Northwest Smart Grid Demonstration Project, which is testing out out a wide range of demand response tools among 60,000 power customers in the region. Overhauling the grid system so everyone can use these tools will be “a multi-decade journey,” according to Carl Imhoffe, who heads up the smart grid program for the Pacific Northwest National Lab.
Mark Osborn, Portland General Electric’s expert on delivering renewable power, explained how smart grid will help make delivering wind energy easier by allowing managers to adjust power demand to match the changes in the wind power supply:
“A wind turbine is going to vary its output depending on how hard the wind is blowing. What the smart grid technologies do is they allow us potentially to respond to that variability with changes in our customer loads so if we see the wind dying down, for example, and we have a way of turning off a few unused lights or changing some temperature settings we can move the load at the same kind of rate that the wind is dying down.”
PGE is experimenting with adjusting commercial and industrial lighting, tapping power in the back-up generators at hospitals and data centers, and as part of the smart grid demonstration project, it is installing a 5 megawatt lithium ion battery storage system in Salem. Osborn says the battery will be used as a proxy for electric cars, which can sop up energy when there’s lots of wind and power is cheap and give it back when power is in high demand and prices are higher.