In my experience, people often unknowingly divide green power sources into types they've seen (solar, or sometimes wind) and more exotic types they'd like to see (tidal, for example). The Renewable Northwest Project list of green power sites
follows this pattern; it includes wind, solar, geothermal, and even some rather speculative wave/tidal projects, but it does not includes any biomass. And why should it? Biomass projects are not as common as solar, not as majestic as wind, and not as futuristic as tidal.
In short, waste-to-energy does not photograph well. The picture above is a 28MW wood-burning plant that also provides steam to a lumber mill. Similar plants can run on natural gas or coal, making distinguishing green energy difficult. However, cogeneration of electricity and steam is one of the most efficient processes we've invented, and burning waste for "combined heat and power" (or CHP, another name for cogeneration) becomes the very definition of sustainability.
Well, if simply being industrial-looking is acceptable for green energy, perhaps people don't notice cogeneration because it's relatively rare. Well, let's compare it to wind. According to the American Wind Energy Association project list, Washington currently has 1479MW of wind turbines at ten separate sites; Oregon has a few less turbines but a couple more sites. Estimated energy production is about as much as a large coal-fired power plant, but less predictable. A much less-well-known database of combined heat and power plants gives up its numbers grudgingly, but it shows that Washington is home to almost 300MW of wood-burning cogeneration plants while Oregon hosts 400MW, spread all across the two states supplying heat to about thirty lumber mills and paper plants. Although these green electricity generators produce only about half as much power each year as the Northwest's wind turbines, the CHP facilities are much more likely to be running when the electricity is most needed.
So combined heat and power is more widely distributed than wind, more reliable, AND super-sustainable; to its detriment, the technology can't claim to be new--some of these plants have been producing electricity for decades. So while solar photovoltaic gets tremendous attention along with enormous subsidies, cogeneration keeps producing a hundred times more power at competitive prices.
I hope that the lack of visibility doesn't keep people from considering the potential of waste-burning CHP for non-timber-industry applications like district heating. This has the potential to scale up rapidly and make a difference much more quickly than newer technologies; green power has been coming from Northwest forests for years, and I hope it comes to a neighborhood near you soon.