The article “Solar panels could save nearly $1 million per year” highlighted the College’s historical conservation efforts and our goal of consuming only what we need to support the activities of the college. The staff writer did a good job consolidating this complex subject into an article.
Let me take this opportunity to provide a little more information about the photo voltaic (PV) opportunity the College is considering. The goal of our current efforts to bring PV to the College is to use a power purchase agreement (PPA). In a power purchase agreement, an institution contracts with a PV firm to install and operate a PV system on the institution’s property and to purchase the electricity generated by the panels at an initial defined KWH cost with an agreed upon annual inflation for a specific length of time. At the end of the time period, usually 20 years, the panels become the property of the institution.
Since the expected useful life of PV panels is 30 years, the cost of the generated electricity between 20 and 30 years is zero other than maintenance of the system for the remaining life of the panels. The use of a PPA allows an institution to take advantage of the cost savings and rate stability resulting from a PV system without incurring the cost of installing the system.
A little clarification is in order about the district system which currently supplies heating water (HW) and chilled water (CW) to Hoover, SMEC, Steinman, Nicarry, Zug, Wenger and the Library. This system takes advantage of the large mechanical room in the basement of Nicarry where boilers and chillers generate and pump CW and HW to these buildings. We are in the final stages of making the internal connections of the library HVAC system to the district system, and once this is completed, we will be able to heat and cool the library from Nicarry. While the piping was extended into the Zug mechanical room, conversion of the Zug HVAC system from heat pumps to a four-pipe system will be a future project. The advantages of a district system are many and were reviewed in the Etownian article, but in the library the district system CW/HW will replace the original electric heat, chiller and cooling tower. Replacing the chiller and cooling tower in the current configuration would cost $650,000 with the building remaining all electric. Due to the immediate need to replace the original heating and cooling system there is considerable construction savings and long-term energy savings by connecting the library to the district system.
When we designed the extension of the district system, we made provisions for future connections to Alpha, Myer, Ober and Brinser so that these buildings could be connected in the future. The provisions are limited to valves and connection points in the piping and sufficient capacity in the size of the lines. At this time there are no plans to extend the district system piping to these buildings.