HomeMy WebLinkAboutDelta Greely School District - Biomass Case Study - August 2015 - REF Grant 2195395Quick Facts
Total Project Costs: $2.8 million
Funding: Renewable Energy Fund: $2 million
Other State Funding: $800,000
Capital Costs
Design: $248,086
Construction: $2,551,914
Equipment
Chipper Make/Model: Rotochopper MC-266
Output: 200 yards/hour for Spruce trees
Boiler Make/Output: Messersmith, 5.5 MMBtu/hr
Diesel Fuel Offset
Estimated annual: 60,000 gallons
Actual annual: 29,000 gallons
Comprehensive savings: 96,000 gallons
(Sept. 2011-Dec. 2014)
Fuel Savings
Estimated Annual: $135,000
Actual Annual: $97,000
Comprehensive savings: $297,000
(Sept. 2011-Dec. 2014)
Delta Junction, Alaska
Biomass project saves teaching position and reduces fire risk
Delta Junction Wood Chip Heating
Project Overview
In partnership with the Alaska Energy Authority
(AEA), the Delta Greely School District designed
and constructed a wood chip boiler system to heat the
Delta School. Hot water is piped from the boiler to the
school’s existing heating system. The diesel-based fuel
system remains in place as an automatic backup.
Objectives
• Reduce the energy costs to the school district
• Displace diesel fuel with a local wood fuel
• Develop a chip industry in the Delta area
• Create much needed jobs
• Mitigate wildfire risk
Reasons This Product Was Chosen
The primary reason the community chose a wood
chip heating system over an alternate renewable
energy source was for the added benefit of reducing
wildfire hazards in the area. There are more than four
million acres of forest in the Delta Junction vicinity.
The school also standardized their boiler equipment
with Tok School’s wood heating equipment to stream-
line operations and maintenance.
Economic Feasibility
The project became operational in September of 2011.
Between September 2011 and December 2014, it pro-
duced 9,988 MMBtu of thermal energy and displaced
96,000 gallons of diesel fuel. This displacement has
saved the community $297,000. With proper main-
tenance, the boiler life is expected to exceed 20 years.
Additional benefits will be realized as well; the project
will continue to use an energy source that keeps fuel
payments in the local economy rather and creates
local employment.
Messersmith boiler
system, photo cour-
tesy of Delta Greely
School District.
“In 2015, Delta
combined all
K-12 students
into the high
school build-
ing, allowing all
students to be
warmed by re-
newable biomass.”
Allocation of Funding
The Alaska Energy Authority’s Renewable Energy
Fund contributed $2 million for the purchase of the
wood chip-fired boiler and the construction of the
boiler storage facility. The state also granted $800,000
for the chip storage, vans, labor, and plumbing and
piping costs.
Fuel and Storage
Wood chips are provided by Dry Creek’s Lumber and
Milling Association for $63/ton. They are delivered
from storage via a walking auger and dropped onto a
conveyor belt that takes the chips into the boiler. The
Delta High School Complex’s estimated energy need
is 1,400 to 2,100 tons of wood chips per year. This
roughly equates to 50 to 75 acres of low grade quality
forest, a very low quantity in comparison with the four
million available acres.
Learning Experiences/Challenges
Operating and maintaining a chip boiler is a commit-
ment. The school maintenance worker was not origi-
nally involved in the boiler’s design and was concerned
about the impact to his job. He did eventually become
a strong supporter of the project, but earlier input and
support would have been beneficial and could have
resulted in a more effective design.
Fuel quality is extremely important to the successful
generation of the biomass boiler. Silica-heavy pine
needles, dirt, and other contaminants created clinkers
(chunks of glass) in the combustion chamber and
increased maintenance and downtime. It is a common
misconception that allowing dirt and contaminants to
be burned with the wood isn’t harmful, but doing so
even for a short time proves detrimental to the system.
In response to this situation, Delta began storing their
wood in a dry, covered area with a concrete floor.
Community Benefits
Cost savings from the biomass boiler allowed the high
school to add a teaching position in the fall of 2015 as
well as restart the preschool program. In the school’s
science classes, students participate in moisture test-
ing and visit the boiler facility. Students in the career
vocational program have the opportunity to train in
boiler operations. Community members are excited
about the educational experience because it has the
potential to inspire even more growth and discovery
in local biomass development. In the summer of 2015,
Delta combined all K-12 students into the high school
building, allowing all Delta Junction students to be
warmed by a local, renewable energy resource.
Project Contact Information
Parties Involved:
Laural Jackson, DGSD Superintendent
Email: ljackson@dgsd.us
Phone: 907-895-4657, ext. 21
Bill Burr, maintenance & operations director
Email: bburr@dgsd.us
Phone: 907-803-0003
Case Study Author:
Zoe Tressel, AEA Intern
Website: Akenergyauthority.org
Boiler storage facility, photo courtesy of AEA.
Hurst boiler, photo courtesy of Reba Lean.
Delta Junction Wood Chip Heating
Published August, 2015