Bainbridge Island bio digester HORSE seeks new pasture

BELLEVUE, Wash. (7/18/2017) After the success of a nearly year-long pilot program, the bio digester HORSE is looking for a new home on Bainbridge Island.


By Janet Kim, janet.kim@pse.com

Since early 2016, Puget Sound Energy has partnered with Harbor Public House and Impact Bioenergy to use the HORSE (High-solids Organic-waste Recycling System with Electrical output) to demonstrate the viability of using food waste to make electricity and fertilizer and to further the discussion about a permanent, larger community digester.

“The ‘feeding of the HORSE motivated our staff to look for additional ways of repurposing our waste streams,” said Jeff Waite, the owner of Harbour Public House. “Based on the positive feedback we are experiencing, we think it’s time for a community-wide discussion on how the Island can move on more community-based installations.”

The digester is designed to generate 2,550 kilowatt hours of energy per year. This innovative technology can generate the energy equivalent of one barrel of crude oil from 2,900 pounds of food scraps. It also generates 5,400 gallons per year of nutrient-rich fertilizer that was supplied to local farms. It is a zero waste system which avoids trucking organics off the island.

The HORSE pilot project is a natural extension of PSEs ongoing interest in developing alternative sources of renewable energy. In 2004, PSE began partnering with dairy digesters as part of our Green Power Program. Those digesters turn manure into methane used to fuel an electric generator. PSEs Green Power Program has been recognized by the U.S. Department of Energy and the Environmental Protection Agency (EPA) as a leader in renewable energy development. The Bainbridge Island initiative is moving this focus to urban environments.

“PSE knows how important renewable energy is to Bainbridge Island residents,” said Karen Brubeck, PSE outreach manager. “The commitment is evident through our programs like Green Power, where currently 1,175 Bainbridge Island residents and businesses participate and contribute 12.5 million kilowatt hours of renewable energy to the grid each year. Bainbridge has the second highest participation rate in the Green Power program in our entire service territory, and PSE has taken notice.”

PSE is now funding a second study to determine the viability of a larger, permanent community digester and is in search of a new partner on the Island to host the HORSE for the upcoming year.

To continue the Bainbridge pilot, the deadline to find another 12-month host for the HORSE portable system is September 30.

“We want to thank Jeff Waite at Harbour Public House for being an innovator and taking on this pilot project,” said Brubeck. “It is PSE’s goal to keep the HORSE pilot project on the island to continue the experience. In the meantime, we thank Bainbridge Disposal for offering space to stable the HORSE as PSE looks for a another host once it leaves the Harbour Public House August 1.”