Thermal Storage Demonstration at CCHRC
CCHRC is demonstrating a thermal storage system that uses a massive tank of water to seasonally store energy from the sun. There is growing interest in using thermal storage in Alaska to replace traditional heating sources. Alaska receives abundant sunlight during the summer but hardly any in the winter, when heating loads are greatest. Thermal storage allows us to capture heat with solar collectors in the summer and tap into it during the heating season.
In 2013, we installed 16 solar thermal collectors and buried a 25,000 gallon water tank in the ground. Solar collectors will transfer heat into the tank in the summer through a heat exchanger, and the radiant floors will draw from this heat in the winter. The system is expected to produce 50 million BTUs a year, or the equivalent of 400 gallons of heating oil, one-third of the building's total demand. This demonstration will provide clues about how to best design a residential system and the potential costs and savings for homeowners. The lessons learned here will be shared to help develop sustainable building and energy solutions for Alaska and other circumpolar communities.
This experimental solar seasonal storage project was funded by a $70,000 grant from BP Alaska, which includes solar hot water collectors and a heat storage system to enable solar energy to be stored and used during the winter. The tank was donated by K&K Recycling.
View Flickr slideshow here.
CCHRC is watching the temperature of the ground underneath the solar thermal tank. The tank is over permafrost and could melt the permafrost in that location significantly. Click here to view daily ground temperatures.
Read an Economic Case Study of the system here.