HomeMy WebLinkAboutWrangell Hydro Boiler Case Study - REF Grant 2195423 est 2015Wrangell, Alaska
Wrangell Hydroelectric Boilers
Quick Facts
Total Project Costs: $1,938,745
Funding:
Renewable Energy Fund: $1,862,387
Local Funds: $76,358
Capital Costs:
Design: $288,175.04
Construction: $1,650569.96
Equipment
Boiler Make: Precision Boilers (3)
Output: 160 kW (Nolan Center), 240 kW
(Public Safety), & 700 kW (Schools )
Diesel Fuel Off set
Estimated Annual: 100,000 gallons
Actual Annual: 84,000 gallons
Feb. 2011-Dec. 2014: 305,000 gallons
Actual Fuel Savings
Estimated Annual: $163,112
Actual Annual: 145,000
Feb. 2011-Dec. 2014: $640,000
Estimated Payback: 8 years
Actual Payback: 13.4 years
CASE STUDY
Wrangell, AK. Photo courtesy of www.sitnews.us
Project Overview
In collaboration with the Alaska Energy Authority,
Wrangell Municipal Light & Power (WMLP) com-
pleted the design, construction, and integration of 3
electric boilers in Wrangell, Alaska. Th e new electric
boilers convert wasted overfl owing water from the
Tyee Lake Hydroelectric facility into usable energy.
Th e three building complexes that directly benefi t
from this energy are the Nolan Center, Public Safety
Building (home to the fi re hall, court, and public safe-
ty hall), and the High/Middle Schools.
Objectives
Th e main objective of this project was to reduce the
community’s reliance on diesel fuel-powered facilities.
Th is would ultimately reduce community members’
cost of energy and heat production while lowering the
city’s carbon footprint.
Reasons This Project Was Chosen
Wrangell was using 2,982,822 gallons of diesel fuel
annually to heat their entire village. Th e new electric
boilers’ capacity and effi ciency have allowed villagers
to use a cleaner source of fuel and saved them thou-
sands of dollars. Using an electric boiler also reduces
maintenance costs when compared to diesel boilers.
Economic Feasibility
Th e system became operational in February of 2011.
Since then, it has produced 30,090 MMBtu of thermal
energy and displaced 305,000 gallons of diesel fuel.
Th is displacement has saved the community $640,000
in energy costs. Over its 20 year projected lifespan,
the project has a calculated benefi t/cost ratio of 1.91,
meaning that the benefi ts outweigh the costs by 1.91.
the heat with the same amount of electrical energy.
3. Any overages in energy output at the Tyee facility
are given to WMLP by SEAPA in the form of a re-
bate equal to the overage amount. Th is has allowed
Wrangell to keep their electrical rates at a subsidized
eight cents per kWh. Th is helps residents with heating
costs and encourages them to use electric boilers in-
stead of diesel. Th is rate has been unchanged until re-
cently. Due to projects that SEAPA is performing with
Tyee’s excess water, there is not as much overage as
Wrangell normally anticipates. As a result, rebates were
lowered and electricity rates were increased slightly to
8.5 cents. Th ough this isn’t a huge bump, WMLP hopes
to bring the cost back down for residents soon.
Community Benefi ts
1. By implementing the conversion to electric boilers,
the surplus energy produced by Tyee is utilized and
the cost of energy for City facilities has decreased by
approximately 48%. Th ese savings have been passed on
to WMLP customers through a decrease in taxes and
power rates, which benefi ts all Wrangell community
members.
2. Th e Tyee Hydroelectric Facility has provided a
steady electric rate to WMLP for 6.8 cents per kWh
for the last 17 years. Th is is a benefi t to the community
when compared to the constantly fl uctuating costs of
diesel fuel.
Project Contact information
Parties Involved:
Clay Hammer, WMLP Superintendent
Email: powerplant@gci.net
Phone: 907-874-3602
Brooke Williams, WMLP Secretary
Email: wmlp@gci.net
Case Study Author:
Zoe Tressel, AEA
Email: ztressel@aidea.org
Phone: 907-771-3000
Hydroelectric boiler. Photo courtesy of WMLP.
Power and Storage
Electrical power is provided to Wrangell Municipal
Light & Power (WMLP) by the Tyee Hydroelectric fa-
cilities, owned by the Southeast Alaska Power Agency
(SEAPA). Currently, Tyee has the capability of produc-
ing 20 MW of power. During the summer months, ap-
proximately 11 out of the 20 MW are excess power and
during the winter 6-7 MW are excess. Diesel fueled
generators remain as ready backups should an electri-
cal catastrophe occur. Additionally, all public facilities
that were converted to electrical energy have oil fi red
boilers in place as a back up energy source.
Learning Experiences/Challenges
1. Th e original application identifi ed eleven buildings
for conversion to electric boilers. Due to a reduction in
funds it was only feasible to construct heating sys-
tems for the Nolan Center, Public Safety Building, and
High/Middle Schools. Th ese buildings were ranked
according to highest community need and value.
2. With the success of the project, private homes and
businesses followed suit. WMLP is fi nding that the ad-
ditional electric demand has a negative impact on their
distribution and stand-by generation capabilities. Th ey
have partnered with Cold Climate Housing Research
to promote air source heat pumps as alternatives to
resistance-based electric boilers for future community
growth. Th ese pumps can produce up to three times
Wrangell, Alaska