Juneau builders find heating solution underground, but it’s not what you think
Rising fuel prices have long put builders on the lookout for a viable alternative to expensive boilers with low efficiency.
In Juneau, the answer has come in the form of heat pumps.
The new facility would replace the library that’s been renting space in the Mendenhall Mall for more than 25 years.
If awarded, the grant would provide more than one million dollars of the estimated $1.3 5 million needed for installing the heat pump.
The proposed library heat pump would be one of several in Juneau.
Three are already in operation and another three are under construction.
As CBJ Engineering Director Rorie Watt explains it, ground source heat pumps use tubing deep in the ground to bring heat to the surface.
The growing number of heat pumps in use is a reflection of the advancement of the technology, Juneau’s geothermal resources and the opportunity for fuel savings.
Alaska Electric Light & Power installed the first Juneau heat pump in the late 1990s. Now the company has 21 heat pumps in its building in Lemon Creek.
Alec Mesdag is the Energy Management Specialist for AEL&P. Mesdag estimates heat pumps will save the company 50,000 dollars over 25 years.
The Dimond Park Aquatic Center and Juneau International Airport installed ground source heat pumps in 2010.
The airport terminal added approximately 12,000 square feet during the construction project. Roughly half the building is heated by 31 pumps.
Consulting engineer Doug Murray calls the savings so far “pretty incredible.”
In October, Juneau voters approved a bond issue which will provide another 6.9 million dollars to the airport. Some of the funds will be spent on more heat pumps, an expensive technology upfront.
Rorie Watt estimates the increase in construction costs to be as much as 50 percent.
AEL&P’s Mesdag says that long-term savings are the main reason ground source heat pumps are becoming more common in large projects, especially public buildings.
For more information check out these documents:
Airport Project Report: A Brief Report to the Alaska Energy Authority