Basic Wind and Compost
Wind generation came to St. Olaf in support of Regents Hall of Natural Science. when it became clear that Regents would happen in the mid to late 2000s, we started scrambling to find ways to off-set the Operations and Maintenance expense of this large, technical, traditional energy hog building type..
First, we specified that the St. Olaf Sustainable Design Guidelines would guide planning, design, and construction. It ended up being a very efficient building, and consumes just 25% of the predicted energy if it was built to the Minnesota Energy Code. Even with that, the operating cost might have been $1,000,000 per year. This incremental improvement in building quality saves over $430,000 per year on electricity expense through avoided cost.
So, the second step was to find opportunities to further off-set the cost of O&M. We settled on generating our own renewable electricity on campus – this is called self-generating. Consuming the kilowatt hours (KWH) directly means we can avoid the cost of purchasing those KWH. Regents is using about 2,100,000 KWH, and because they are sustainably generated by wind, we avoid an additional expense of just over $150,000. The wind turbine production is officially dedicated to Regents through the LEED work, and so, the joint project saves nearly $600,000 per year. In addition, the KWH come with no carbon, and the excess KWH more than off-set the small increment of natural gas at the heating plant. Regents’ main heat source is the lab exhaust air, which goes through a heat reclamation system, and no steam is used at the air handlers until it goes below -10 f. outdoors.
A presentation we do for school groups follows. It does not work well without some narration, but you will get the big ideas.