While I was standing in line at the library the other day I noticed a magazine from Washington State's Public Utility Districts. Public Utility Districts (PUDs) are county government units that own hydroelectric dams and other generating facilities, as well as a high-speed fiber network across WA and OR. The article that caught my eye began like this:
ADAGE and Energy Northwest signed today a preliminary agreement to develop wood waste biomass power plants in the states of Washington, Idaho, Montana and Oregon. According to the agreement, the companies plan to jointly market clean wood biopower (biomass to electricity) to the 24 member utilities that comprise Energy Northwest, and to other regional utilities, with the goal of constructing and operating one or more 50 megawatt (MW) power generation plants in these states.
The article I'm quoting from is here, and is not as complete as the magazine article I read today. The magazine article indicated the plan was for more than a gigawatt (a thousand megawatts) of installed capacity - more than 20 plants.
Energy Northwest (EN) is a non-profit consortium of PUDs and Seattle City Light - 24 members in all, including my county's PUD. EN also operates a nuclear facility, a couple small hydro dams, a wind farm in SE WA and has begun developing solar facilities as well.
ADAGE is a joint venture between AREVA and Duke Energy created to provide clean, biopower energy solutions to U.S. electricity customers. Within the joint venture, AREVA will construct the biomass power plants, and Duke Energy Generation Services, a Duke Energy business unit that owns and develops renewable energy, will operate the facilities.
That isn't quite as heartwarming, all though it's interesting to note that AREVA is a large nuclear plant operator (ironically, 90% owned by France, who sold much of the land in the 4 states involved to the US in the Louisiana Purchase).
Duke Energy is a large, private electric utility. They're the 46th largest corporate producer of air pollution in the US, mostly due to coal plants, which they continue to build, but they also have 500 MW of wind power on line and another 5000 MW in development.
Neither the magazine article nor the linked article provide a lot more details, so what follows is just a general discussion.
In terms of economics, this is a really interesting plan. First, the technology, except for actually processing the wood fuel, is all mature, existing technology - the same as coal-fired plants, but without a lot of the toxic emissions or waste disposal problems. The plants shouldn't require much in the way of new grid infrastructure beyond the immediate interface to the grid that any new facility would require.
The idea of distributing smaller plants is also attractive. For one thing, it means the biomass won't have to be transported great distances to the plant. For another, both the collection of biomass and the operation of the plant will create local jobs - WA and OR both have unemployment rates above the national average at the moment of over 10%.
The magazine article specifically mentioned using wood waste. It's unlikely that logging as it would be generally thought of would be used to generate fuel. There are literally tons of wood waste per acre in the states mentioned. Wood waste consists of dead trees, wind throw, post-fire salvage and logging slash. Somewhere around 1/3 of the mass of every tree cut is left on site as slash - branches, stumps, unusable trunk sections and tree tops. Properties around my house that have been logged have large amounts of slash - I heated my house with logs from slash piles for the first 10 years I lived here, and I haven't used up that source yet. Salvage logging has come under criticism in coastal areas of the NW, where forests are nutrient-limited and dead matter nutrients are recycled if left in place. The interior forest areas in the states mentioned are arid and water-limited and leaving dead matter behind is mostly a fire hazard. The logs I'm still pulling out of slash piles were cut 20 years ago and most have very little rot.
In addition there are hundreds of thousands of acres of forest in the states mentioned that are overgrown due to fire suppression, and now a big part of the wildfire problem in the west. Those are both public and private forest, and in restoring them one of the most difficult problems is disposing of the biomass removed in thinning.
Small trees (under 6 inches in diameter) are a major part of the problem, but so is woody brush. However I don't know whether brush will be used for fuel in these plants. When I initially thinned my woods, I removed more than 5 tons per acre, a lot of which went to firewood, but a lot of which was burned in brush piles too. It is more difficult to collect brush or small trees, but it doesn't require large machinery, underground tunnels, open pits or blasting, so is a lot safer and less capital intensive than coal mining. Dry wood or wood fiber by weight contains about 2/3s the energy of the equivalent weight of coal.
Because these plants use existing technology, construction can begin as soon as the plans are drawn up, and because they're smaller plants, they can go online more quickly. And these plants are immune to the criticism sometimes leveled at wind and solar - they provide baseload power. They're not a globally-applicable solution to energy problems, but they are an appropriate local solution.
I've felt for a long time (and conservation groups like the Wilderness Society have too) that this is a major overlooked source of renewable, relatively non-polluting and net non-CO2 generating energy. The CO2 emitted was removed from the atmosphere in the last 10-20 years, not sequestered millions of years ago , like fossil fuels, and as forests regrow, they recapture the CO2 released in burning. Even the ash can be returned to forests as a soil amendment.
Even if all of the opportunities this plan presents aren't utilized, it still appears to be a net positive. If all of the synergies this plan could produce are developed, it would be a significant benefit to the rural northwest environmentally and economically, as well as having the potential unique feature that extracting resources for energy creation could be environmentally beneficial.