Green innovation turns Elizabethtown College
food waste into electricity
Customer Profile
Elizabethtown College, located near Harrisburg, PA is a
private, residential co-ed college of 1900 students living on 200 acres.
The Waste Reduction Challenge
Director of Facilities Management and Construction Joe Metro and local farmer Mike Brubaker
wanted to partner on a project that would use the College’s
organic waste to create electricity. According to Metro, this effort is part of
the College’s long-term commitment to protecting the environment. “For many
years Elizabethtown College has taken a proactive approach to the efficient use
of water, natural gas, fuel oil and electricity and in the reduction of the sanitary
waste and solid waste we generate,” he says.
Solution
Director of Dining Services Eric Turzai was
already field-testing a Somat waste pulping system that would
reduce the volume of organic material and allow for
reduced water consumption in the College’s Marketplace eatery.
In the process,
food waste is carefully sorted by Elizabethtown’s Dining Services team, ground
up and then piped to the Somat Company extractor, which
“dewaters” the organic material. The solids and the wastewater are transported
twice a week to the Brubaker farm.
At the farm, the
organic material and wastewater are mixed with cow manure and fed into a
digester. In the digester, the organic material catalyzes the production of
methane gas from the cow manure. The methane is then harvested and used to
power an engine/generator, which creates electricity. The residual wastes,
which have been sterilized by the microbial process in the digester, are used
for bedding and fertilizer at the farm.
Organic waste being fed into digester
Results/Environmental Impact
While colleges and
universities nationwide have composted organic materials to reduce waste and
limit their environmental impact, few are using the resulting material to
create electricity. None have combined these projects with a system that reuses
water. By marrying these sustainability efforts, Elizabethtown College and its
partners have created a workable system that is producing enough power for
about 200 homes and significantly cutting water consumption and waste at Elizabethtown—proving
that even a small college can take a big step toward protecting the
environment
The unique water
recycling aspect of the Elizabethtown College system reuses 4,400 gallons per
week. Additionally, no byproducts of the pulping process, neither liquid nor
solids, enter the sanitary sewer system on campus. The recycled water is
collected at daily shutdown time and transported twice a week to Brubaker Farms
for use as gray water. Since implementing the system, Elizabethtown College has
lowered water consumption by approximately 80 percent and cut waste hauling
charges in half for the College’s Marketplace Dining Facility. It has been
called a “best practice” in sustainability.
The project has been a win-win for all the project partners and, most importantly,
for the Earth. Mike Brubaker is creating electricity that he can sell back to
the electric company. And, Somat Company is gaining invaluable operational
experience with a piece of equipment that may be in greater demand as more environmentally-conscious
institutions, like Elizabethtown College, seek opportunities to keep our planet
green.