UPDATE 12/29/11: The Alaska Energy Authority grant for geothermal ground source heating in the new library was not recommended for funding.
It is very efficient. Just how efficient will be determined as the building operates. Extensive energy modeling was done during the design phase to reduce energy demand.
Geothermal ground source heating is also being considered. The upfront costs are high, so this is not currently part of total project cost. An Alaska Energy Authority grant is currently being prepared that could fund up to 80% of the upfront cost.