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When Woody Biomass Brings Music to Your Ears!

By Barbara Coyner

Did you know that kids who learn music get better math scores? Did you know that kids involved in gardening are less apt to turn to crime? And did you know that a school district that utilizes woody biomass has saved enough money on heating and energy costs to hire a full-time music teacher AND build and heat a commercial greenhouse?

Savings Thousands of Dollars & Potential Wildfires

These are just some of the benefits an Alaskan school district is enjoying, while at the same time thinning adjacent forests to lessen wildfire danger. Indeed the Tok School in Alaska’s rural Gateway School District could be the poster child for prudent woody biomass usage since firing up its 5.5 million BTU biomass boiler in 2010. The giant boiler measures 17 feet tall, six feet wide, and 12 feet long, and digests a diet of mill wastes, branches, and wood chips ground up by a Rotochopper.

The Tok story is exciting on several fronts. First there is the ever-attractive numbers game. After bringing the boiler online, the school district is now saving as much as $350,000 per year in heating and electricity costs.

The efficient wood boiler produces steam for a turbine that powers the school. Then the steam warms up glycol that heats the school. The feedstock is a massive pile of wood chips made from trees cut to reduce wildfire risks near the community, which is surrounded by thick stands of spruce.

The small town of under 2,000 residents has been prone to wildfires because it is situated on 40,000 acres of continuous fuels. Over the last 25 years, more than two million acres in the entire region have gone up in smoke.

Fine Tuning

With the Tok system, chips feed onto a thin conveyor belt that slowly dumps them into a giant boiler. Things kick into gear when three pounds of wood are added to the boiler.

Of course like all woody biomass projects, tinkering with the wood supply has been critical, and the system briefly had a problem with consistent fuel. The silica-heavy pine needles melted in the boiler and left chunks of glass, clearly gumming up the boiler. The Artic winters present some challenges to burning wood evenly, as well. Yet the school officials and boiler operators have persevered, amending the wood supply and delivery system to overcome the obstacles.

Added Benefits

Once beyond the technical difficulties, the Tok School has taken its wood-based heating and power system to a whole new level, providing amazing ideas for other school districts. For example, initially the school district wanted to build a heat loop to provide heat to other community buildings, but they couldn’t find funding for the project. Instead, the school added a commercial greenhouse that is warmed to a comfy 70 degrees using the excess heat from the system. The idea was certainly better than leaving doors open when the classrooms got too toasty. The greenhouse uses wood chips for flooring, helping with insulation and also facilitating easier planting of the beds right on the wood chips.

The greenhouse contributes some definite value-added aspects in terms of fresh food for the school cafeteria, and the kids are seeing the advantages of growing their own produce. Along with that, students are also getting lessons in soil health and nutrition, as the residual ash from the boiler is used as a soil amendment. The school has cleverly re-purposed old highway guardrails as planting troughs, adding another layer of practical education.

And there is more. Given the steady temperature of the greenhouse, even in Alaska, the school is growing tomatoes and such, processing sauces and salsas. The school cooks hope to create dishes like lasagna that can be frozen and served later, eliminating questionable preservatives in the school diet.

Tenacity

Amidst all the value-added angles, one has to credit assistant superintendent Scott McManus with bird-dogging the concept for over 10 years before it came to fruition. Jeff Hermanns, a Tok area forester, also fought the good fight for the boiler system.

Once the project got the green light, it became a partnership among the Division of Forestry, the Tok community, the Alaska Gateway School District, and the Alaska Energy Authority. They used research from the University of Alaska Fairbanks and elsewhere. Funding came from a $3.2 million state renewable-energy grant, as well as about $750,000 in grants from the Alaska Legislature.

This is definitely the kind of innovation and education that kids and rural communities need. School children learn about the cycles of nature, from forest health, to soil health, to food health, while the school district banks huge savings using woody biomass power. The district’s music program, previously phased out for lack of funding, is back in tune, and there have even been enough savings to add a guidance counselor.

What’s not to like about such a practical approach? With many in the West’s logging community also serving on school boards and city councils across the U.S., the Tok case study provides some great ammunition for school districts to embrace woody biomass power wherever and whenever they can.