Green Brief: BioEnergy can impact climate change

It’s possible to imagine and create more constructive systems for waste management.

Note: Green Briefs is a regular series of commentaries by environmental leaders on Vashon, presented by The Beachcomber in partnership with the Whole Vashon Project.

Imagine a locally available and affordable way for islanders to reduce carbon emissions and waste generation that also helps to grow abundant, healthy produce and provide meaningful jobs. It’s here. Impact Bioenergy has been quietly developing and delivering sensible technology that will do this.

Since 2014, Impact Bioenergy, in collaboration with Zero Waste Vashon, has worked to bring community-scale anaerobic digestion to the island. Impact Bioenergy is now operating a 1,500 ton per year, community-scale anaerobic digester at the Island Spring tofu factory to turn the tofu waste product, okara, into upgraded biogas (ORNG, organic renewable natural gas, a.k.a. Orange), and probiotic food (PBF) for soil and plants. They also grow vegetables on the roof of the digester to utilize the waste heat and CO2 from the digester. The result is the Vashon Bioenergy Farm (VBF).

PBF is excellent for growing vegetables or ornamentals, and it helps to sequester carbon in the soil while improving crop yields and the soil microbiome. The microbiome is the dynamic community of microorganisms living in plants and soil.

The creation of these products is a great story in the race to fight climate change. PBF is a soil amendment and plant food registered with and approved by the Washington State Department of Agriculture (WSDA) for use by certified organic producers.

According to Lisa Hasselman, who co-owns WSDA certified Forest Garden Farm on the Island’s north end with her husband, Chris Hedgpeth, the couple did a side-by-side trial in 2020 pitting PBF against their standard liquid fertilizer (compost tea and fish emulsion) on their winter squash. PBF won with a 30% increase in squash produced and it took less time for them to use.

“This year,” she added, “we are using it throughout our farm foliar feeding with a backpack sprayer and/or through a simple fertigation system attached to our drip irrigation system. We’ve already seen increased yields throughout the farm.”

The Impact team currently uses ORNG (off-gassed methane converted to renewable fuel) to power a small vehicle fleet, including a one-ton F-350 truck. The team is already piloting ORNG as a viable propane substitute for equipment and vehicles. Imagine powering a car with gas that used to escape into the atmosphere.

Vashon Bioenergy Farm’s operation is drawing down 1,500-plus metric tons of CO2 equivalent each year — the same amount of greenhouse gas as 10,000 Douglas fir trees. Growing mega gardens with powerful homegrown products is one way every islander can address the climate crisis fight right now. And soon we may be able to run our vehicles on homegrown fuel as well.

This enterprise is one example of how our island community can begin to manage the waste we produce by repurposing it for energy and other uses. By adopting the mantra, “There is no waste, only resource,” it’s possible to imagine and create more constructive systems for waste management. There are many emerging ways to turn organic waste into useful products and remedial systems that can even become viable businesses creating green jobs.

The Whole Vashon Project is committed to researching and reporting on those innovations. Who knows? One day the 118 and 119 buses and many of our personal vehicles could be powered by locally generated fuel. It makes the imagination go wild.

Srirup Kumar leads Impact Bioenergy in the areas of community engagement, operations, and partnerships. Terry Sullivan is a longtime island resident, active in community projects, and the ten-year author of the “Road to Resilience” column. Find more information about Impact Bioenergy at, or on Facebook or Instagram (vashonbio), or call 206-880-0387.