Longmeadow: Cost-Benefit Analyses for Sustainable Projects Mara McPartland and Claiborne Dingledine - Climate and Energy Solution Analysis, December 2009 The issue that we chose to address through this project was to work through cost-benefit analyses for a series of renovations designed to improve the efficiency and reduce the carbon footprint of Longmeadow House at Bennington College. Starting in fall semester of 2009 Longmeadow was designated to be a campus house for students committed to living an environmentally friendly lifestyle. Adjacent to Jennings Music Building, Longmeadow is quite possibly the oldest house on campus. Although a lovely house in a scenic part of campus, it is currently ill- equipped to be an eco-dorm. A combination of leaky faucets and incandescent lighting make it an environmentalist's nightmare. However, it could provide Bennington with the opportunity to show its' support for the environment and ultimately save money through the implementation of the following projects. Facts and Figures: ● Bennington pays $.13 per kilowatt hour. ● One gallon of heating oil costs $2.60. ● There are 22.4 Lbs of CO2 to one gallon of heating oil. ● One gallon of heating oil contains 1000 BTU's ● One kilowatt hour is equivalent to 3412 BTU's ● The cost of electricity is projected to go up 4.0% each year. ● Heating oil is projected to go up 2.6% Switching from Incandescent to CFL Lighting ● Simple as it may sound, making this simple switch can save a significant amount of energy and money. Installing Low-Flow Shower heads ● These calculations represent the costs and benefits of converting an individual shower head to a low-flow fixture. There are three showers in the house. ● We approximated that they will last around ten years. Evacuated Tube Solar Water Heating ● Despite Vermont's often cloudy skies, solar water heating can prove to be very cost effective, reducing domestic water heating costs by up to half. ● Although there are many different designs for solar water heaters, the most efficient type for this area are evacuated tube solar collectors. A liquid such as water or alcohol flows through a clear pipe surrounded by an evacuated glass tube and collects heat from the sun. The heated liquid is then run through a heat exchanger, raising the temperature of the water in the tank. The evacuated air space prevents heat from being lost, and keeps the water from being affected by outside temperatures, making them effective even in the cold. ● The system we propose would run for approximately 30 years and would include two 7.5x7.5 foot solar collectors, together providing an average of around 62,400 BTU's per day. The system would be placed on the south facing roof of Longmeadow. Photovoltaic Solar Panels ● The photovoltaic system that we propose would cover 334 square feet of space, probably on the south facing slope behind the house. ● The system will provide, on average 7,149 kilowatt hours of electricity per year, which amounts to 46% of total energy use. Pellet Boiler ● The majority of Longmeadow's energy use and carbon dioxide emissions come from space heating. ● Currently Longmeadow is heated by an oil furnace that burns through an average of 2,000 gallons of heating oil per year, emitting 44,441 pounds of carbon dioxide. ● Pellet furnaces function very similarly to conventional oil furnaces, except instead of using oil, compressed pellets of woody material are burned to create heat. ● Pellet boilers require minimum maintenance ● They use the existing infrastructure in the house, and can respond accurately to a thermostat. ● Pellets are carbon neutral. For information regarding these analyses, please refer to our project write-up and data. Mara McPartland - Claiborne Dingledine -