In the 40 years since Congress directed the Bonneville Power Administration (BPA) to meet growing energy needs through renewables and efficiency, the agency has saved 2,350 average megawatts (MW) through energy efficiency programs. BPA is a federal power marking agency that markets and transmits power from the Pacific Northwest federal dams and one nuclear power plant to more than 130 public utilities, including co-ops, rural electric associations, municipalities, and public utility districts. BPA helps irrigation districts and other irrigators conduct energy audits and take advantage of incentive programs. Hydro Leader spoke with BPA energy engineer Tom Osborn about how, when it comes to energy cost savings, less is indeed more.
Hydro Leader: Please tell us about your background and how you came to be in your current position.
Tom Osborn: I’ve been with BPA for over 30 years. I am currently in our energy efficiency group, working with irrigation-related energy efficiency projects. I work with irrigators, both large and small, and with irrigation districts, some of which irrigate over 200,000 acres. I also work with our federal partners, the Bureau of Reclamation and the U.S. Army Corps of Engineers. BPA is the power marketing agency for federal hydropower resources here in the Pacific Northwest. We market our power to publicly owned utilities. Our power also comes from our two wind farms; one 1,150 MW nuclear power plant; and the Federal Columbia River Power System, which is made up of 31 hydroelectric projects in the Columbia River basin. The utilities to which we market wholesale electrical power include cooperatives, rural electric associations, municipalities, and public utility districts. We have about 130 customers of those types.
Hydro Leader: What percentage of your power comes from hydropower generation?
Tom Osborn: Over 90 percent. The precise figure depends on whether the nuclear power plant is scheduled for an outage in a given year and how much water we have available in snowpack.
Hydro Leader: You work primarily with irrigation districts and other irrigators. Where does their power come from?
Tom Osborn: The irrigation districts have access to Reclamation reserve power. The irrigators purchase their power from local utilities.
Hydro Leader: Please tell us about BPA’s efficiency programs.
Tom Osborn: The BPA energy efficiency effort started in 1980, when Congress passed the Northwest Power Act. That legislation directed BPA to look at its hydropower, coal, and nuclear system portfolio. It specifically called out wind, solar, and energy efficiency. Energy efficiency gets a credit of 10 percent in our cost calculations. For instance, if we’re considering adding a new combustion turbine power plant to the generation portfolio, power from which costs 5 cents a kilowatt-hour, or energy efficiency, which costs 5½ cents a kilowatt-hour, the 10 percent benefit on the cost for the energy efficiency would make it the more affordable option. But we have to be certain of these energy savings and know when they produce the savings!
We have about $60 million per year in our budget and our revenue forecast set aside for an energy efficiency program. We have programs for residential customers that support the installation of heat pumps, new windows, and smart thermostats. We have programs for residential housing and commercial buildings, which deal primarily with lighting; insulation; heating, ventilation, and air conditioning (HVAC); and thermostats. We have a program for industrial plants that is currently run by a third party that takes a look at the entire process of producing french fries, pizza pockets, dehydrated onions, and so on and recommends more-efficient equipment or processes. We also have energy efficiency programs to address agriculture, which primarily concern irrigation. For some of the utilities we serve, 70 percent of their sales are irrigation related, so it’s really important for them to have incentive programs to help their irrigators become more energy efficient. We also budget $2.5 million for our Energy Smart Reserved Power (ESRP) Program.
The largest dam in the United States, Grand Coulee Dam, was built ostensibly for irrigation purposes. There was not much demand for the electricity at the time. Part of the motivation for the project, which was carried out by Reclamation, was to reclaim 1,000,000 acres of desert land and convert it to irrigated fertile land where crops could be grown—alfalfa, flowers, fruit trees, grapes, onions, potatoes, watermelon, wheat, and anything else that grows. When the dam was built, power was reserved for irrigation district purposes on the wholesale side. The John W. Keys III pumping plant lifts massive amounts of water out of the Columbia River to a high scabland basin at the end of which the federal government built a dam, creating Banks Lake. That created the Columbia Basin Project (CBP). We work with the irrigation districts on lining canals, replacing earthen ditches with pipelines, and building more-efficient pump stations. BPA provides an energy efficiency incentive through our $2.5 million ESRP program, which also helps reduce station service loads. Reducing losses can reduce irrigation districts’ pumping needs.
The dams are owned by Reclamation and the Army Corps, but BPA has the rights to the power output. They generate their own power, and it flows onto the electrical grid. They use some of the electricity to safely operate the dams themselves. Recently, we’ve been going back to the dams and looking at the power substations to reduce the station service load. A particular dam might be generating 500 MW, but it might consume 2–4 MW of station service for its own operations. If we can reduce the station service load required by lighting, fans, pumps, and compressed air usage by 50 percent, then more electricity is available to the grid. The same is true of power substations: they don’t have a separate utility bringing in the electricity; it comes from the substation itself and is typically unmetered load.
About 8 years ago, BPA went into all the dam projects, updated the lighting, and updated the compressed air system with new variable-speed drive air compressors. We’ve helped upgrade HVAC and lighting, especially LED exterior security and high-bay lighting, and we’re putting in T8 LED lights. Every 8 years, I go back and look for new opportunities. We went from T12 fluorescent lamps to T8s, and now we are moving toward direct-wire T8 LED lamps. We also looked at updating the chillers that are used to cool the oil for the big generators, but we didn’t provide any incentives for that, as they were already fairly efficient.
Hydro Leader: Would you tell us about some of your irrigation-focused programs?
Tom Osborn: Our irrigation energy efficiency programs are not just for irrigation districts, but also for utility irrigation customers. In the Pacific Northwest, farms may have a pump station to pump water out of the ground, out of a creek, or out of the Columbia or Snake Rivers. We work with them on variable-frequency drives (VFDs) and more-efficient pumps. Some of their pumps have been in service for 50 years and are rebuilt, machined, or rewelded every 5 years. After a while, their efficiency begins to decline by 1 percent every 5 years. Recently, BPA created a simple incentive program to help irrigators invest in new, more-efficient pumps that can use the same motors and discharge heads. That’s been a popular measure.
There are also advanced irrigation strategies to help reduce the amount of water farmers need to apply. When I first started working in the irrigation sector, impact sprinklers were placed at the top of center pivots and sprayed water 10 feet above the crops. Sometimes that’s okay, as in the case of corn. But for some crops, such as alfalfa, beets, and onions, a lot of water evaporates before it hits the ground. A newer strategy is to place the sprinklers at eye level or, even better, directly on the ground. Then, you have no direct evaporation from the air and all the water is put on the ground. With that approach, the soil can absorb 97 percent of the water, compared to a figure of maybe 65 percent when the sprinklers are on top of the center pivot. This also requires less pressure from the pumping plant.
Farmers today are extremely efficient. The technology they use to control their pumps and pivots and optimize which pumps need to be on is unbelievable. VFDs speed up and slow down the pumps, raising and lowering the number of gallons per minute being pumped and saving a huge amount of energy. Moisture sensors in the ground guide farmers on how frequently to irrigate. Some farmers even use infrared drones and thermal imaging cameras on center pivots to detect which plants are more stressed than the others and require more water. That technology is expensive to implement and is still a couple years away for us, but the technology is there.
Hydro Leader: You mentioned improvements such as lining canals and piping open ditches. Do those measures save electricity because they reduce the amount of water that needs to be pumped?
Tom Osborn: That is correct, especially in the large CBP irrigation districts. The Keys pumping plant lifts water from the river 280 feet to the storage canal, and its 12 huge pumps are 65,000 horsepower each. Six of the units are designed to be pump generator units.
Hydro Leader: Do all these efficiency programs go through the local utilities?
Tom Osborn: The programs for the irrigators go through the local utilities. The projects for the power substations, the dams, and the large irrigation districts go directly through BPA. Irrigation districts can also get grant funding through Reclamation’s WaterSMART program. Some irrigation districts also apply to the state environmental protection agencies for funding.
Hydro Leader: Does BPA identify the improvements that it wants irrigation customers to make, or do customers propose their own ideas?
Tom Osborn: About half the irrigation projects are proposed by the irrigators. They might need a VFD, new LED lights, or new irrigation sprinkler equipment. The other half are initiated by the utility, by BPA, or by one of the contractors that support the utility efficiency programs. We have a couple of people who work in the field with utility customers. They might educate people about rebate programs, perform a pump test, do a lighting audit, or provide a list of electricians or contractors that work in their area to do the installation. We also support custom projects, such as replacing an ice rink chiller or the cooling towers at a hospital. We might put a temporary energy datalogger on the facility and record its energy consumption before and after installation of the new equipment to verify the energy savings and calculate the rebate.
Hydro Leader: How do these programs ultimately affect BPA?
Tom Osborn: BPA has been working in energy efficiency since 1980 and has saved over 2,000 average MW. That means is we have not had to procure resources to provide that additional 2,000 MW. Why didn’t we just build more nuclear plants or install combustion turbines? That is because Congress wanted us to look at efficiency first. Since 1980, BPA has thought of energy efficiency as a resource, and Congress has directed us to give energy efficiency a 10 percent credit.
Hydro Leader: Please tell us about your vision for the future of BPA’s efficiency programs.
Tom Osborn: Our efficiency program should be tailored to support the Pacific Northwest’s clean energy goals, which include incorporating energy efficiency. I think it should also include demand response, which means turning loads on and off in response to power system needs. One of our customers, a small utility, keeps its power bill from BPA low by turning hot water heaters off for 15 minutes during peak usage in the morning. They offered homeowners a small credit on their power bill for participating. They’ve been successfully reducing their kilowatt demand using this strategy since 1986, and they are able to shift 10 percent of their load. How can we encourage other utilities to make these kinds of changes? The big question is how to document value in demand response and decide who gets the value or benefit. For instance, does the homeowner receive the value of turning off their hot water heater? In this case, the utility gives the homeowner a small credit on their power bill for participating. Does the electric utility get the benefit? In this case, it does, since it is shifting kilowatt demand. Does the wholesale power, BPA, receive value? Maybe, maybe not. It depends on the day and when our peak is in the morning. What if BPA wanted to shift that load and asked the utilities to push the button at noon? That might not help the utility, and it might shift the demand for a commercial customer and affect its utility power bill. It’s difficult to work all those issues out.
Energy efficiency and its value proposition coupled with the demand component are the future of BPA’s energy efficiency efforts. We will see conversion from natural gas with the electrification of residential housing and commercial buildings, and electric vehicles will be adding to this new demand for clean hydropower energy. The Pacific Northwest will need all the hydropower it can get!
Tom Osborn is a mechanical engineer with Bonneville Power Administration’s energy efficiency group. For more on BPA, visit bpa.gov.