One of the most hotly contested water debates in the West over the past three decades involves the fate of four hydroelectric dams on the Lower Snake River in eastern Washington state.
The dams are operated by the United States Army Corps of Engineers. In conjunction with some two dozen other dams on the larger Columbia River system, they provide hydroelectric power to the vast Pacific Northwest region as well as California.
But they also restrict access to more than 5,000 miles of habitat for spawning salmon. This is cold-water habitat that will become even more vital to salmon as climate change accelerates.
A 2016 federal court decision requires a new environmental study to consider dam removal as one option to accommodate salmon into the future. This raises questions about how to replace all the energy the four dams provide if they are removed.
The Northwest Energy Coalition tries to answer that question with the new Lower Snake River Dams Power Replacement Study. The most comprehensive of its kind to date, the report concludes the four dams can not only be replaced by renewable power, but that grid reliability need not suffer in the process.
Fred Heutte, a senior policy associate at the coalition, explains how that’s possible. The coalition’s member organizations include environmental groups, Native American tribes and local governments.
Water Deeply: What’s unique about this study?
Fred Heutte: There have been other more high-level assessments of this problem. For example: What would be required to replace the dams at a resource level? How much solar and wind would it take? You can do kind of a basic analysis of that. This study we’ve just completed involves a very detailed operational analysis, throughout an entire year, hour-by-hour, that looks at the entire electrical system throughout the West. If you take the dams out and replace them with the clean energy mix, what does it do to cost, emissions, resource adequacy?
Water Deeply: And are the four Snake River dams replaceable?
Heutte: We found the energy from those dams can be replaced without big disruptions. One of the issues has always been that the dams provide a fair bit of energy to regulate the power system. What would happen if those dams were no longer there? How much would it cost? Would it degrade grid reliability?
The Army Corps concluded some years ago – and they only looked at natural gas replacement at that point – it would be fairly expensive and there would be some issue with grid reliability. Well, things have changed a lot since then. Renewable energy has gotten a lot cheaper. The way the grid operates has gotten a lot different.
Water Deeply: What would replacing the dams require?
Heutte: You need a diverse replacement mix that includes both resources on the supply side – wind and solar – and on the demand side – additional energy efficiency, demand response and storage resources. If you combine all that in a smart way, the costs will be manageable and the results could actually improve on what the dams provide in terms of resource reliability.
Water Deeply: What renewable power sources did you look at?
Heutte: The study looks at a fair bit of new wind and solar located at favorable places in the region. It takes advantage of rapidly declining costs for renewables. If you match them together properly, that actually gives us a better match with seasonal demand on the system.
One of the issues with hydropower dams is they only generate power when they have water. The water is driven by spring snowmelt, and it’s fairly low from summer through winter. The effect is, if we can replace the output of the dams with something that’s better tuned to the demands within the region, you can get a good result that way.
Water Deeply: Are we talking about massive amounts of wind and solar?
Heutte: They are not unprecedented in size at all. For example, in what we call the balanced-plus resource portfolio, that would include 750 megawatts of solar and 1,250 megawatts of wind. That’s a lot, but it’s not at all out of line with what we’re seeing in the Northwest and California.
We don’t have solar quite that big in Washington yet, but California certainly does. But we have a lot more wind, something around 6,000 to 7,000 megawatts of wind in the region today.
A lot of solar is on tap right now, waiting to go in, because some of our utilities are starting to open up and buy new renewables, particularly Portland General Electric and Puget Sound Energy. They both have renewable proposals out for bid this year.
Water Deeply: And what changes would be required on the energy consumer side of the equation?
Heutte: We looked at what’s already proposed for energy efficiency in the regional Seventh Power Plan (prepared by the Northwest Power and Conservation Council), to make sure we didn’t double count the cheaper energy-efficiency and demand-response measures.
So, for energy efficiency, we proposed everything from advanced lighting, better motors, more efficient building construction – all those kinds of things.
For demand-response, it would involve recruiting large industrial facilities that can scale back their production for a few hours when the grid really needs it, cycling air conditioning and water heaters. They do this a lot in the East when things get really hot or really cold. Here we haven’t really developed it very much, because in the past we’ve always had a lot of surplus (electric system) capacity in our region. That’s not so true any more.
So demand-response is starting to be studied more, and a lot more refinements are being done. There are a lot of programs that would still have to be developed to capture that demand-response. But there’s a lot of momentum to do that.
Water Deeply: Would these changes cost energy consumers anything?
Heutte: On average, depending on which resource mix you pick, the cost for an average Northwest household residential customer would be on the order of not much more than a dollar a month. This is not designed to be a very precise analysis. It gives a general sense of what the impact would be. But given that a typical household bill is $80 or $100 a month, it’s not a huge percentage amount. We’re looking only at the power replacement cost. We’re not including the cost of either keeping or removing the dams.
Removing the dams would cost a lot of money, but keeping the dams we actually think would cost a lot more. The lower Snake dams are at a point now where significant upgrades or replacements have to occur. And that’s not going to be cheap.
Water Deeply: Is all this feasible politically?
Heutte: We hope so. This is a long-term project and it’s a big issue. It involves a really fundamental question: Can we preserve the environment, the natural resources we have – in this case, the fish – and also provide benefits like clean energy to our region and continue to provide the really important value of the hydropower system, which is how flexible it is? That’s providing a value to the West, especially California.
Governor Jerry Brown has directed the state agencies to take a look at what can be done to improve the arrangements in California that allow Northwest hydropower to come down and provide benefits to the changing California resource mix. More solar creates more opportunity and challenges, because in the middle of the day when there’s a lot of solar power, the way the grid operates is changing. Can we provide that flexibility? I think the answer is yes. It’s going to take a lot more work.