All posts by isabel.smith

Geothermal Energy for Morledge House!

I propose that Morledge Hall gets switched to geothermal heating and cooling to save money and increase the amount of renewable energy being used at Eden Hall. Currently about $4700 is spent on gas and electric for Morledge Hall now (building used for K-12 education outreach). By switching to a geothermal system, 30-60% on heating and 20-50% on cooling costs can be saved and Eden Hall will be even more reliant on renewables instead of fossil fuels. Geothermal systems are also low maintenance and last a long time with the indoor components lasting about 25 years and more than 50 years for the ground loop. Using a BTU calculator, based on the size of 2,401 ft2, an average ceiling height of 8ft, about 4 people inside the building, and average conditions on sun exposure and climate with poor insulation then Morledge House uses 61,824 BTUs or 5.2 tons. This would mean Morledge House needs a 5-ton geothermal unit. Before the geothermal system is added, the insulation should be improved so heat is not being lost. A contractor will help size the other pieces and parts like the boreholes and depth of locations of the pipes. A procedure called Manual J is completed to determine the heating and cooling loads (capacities) based on the house structure, size, number of doors and windows and the type, insulation, duct leakage, winter and summer conditions and other factors. This will be a more exact evaluation to determine the number of Btus needed. Manual S procedure is used to select the right equipment such as the duct work for the proper air flow, air handlers, electric resistance heat, thermostats. A contractor would also have to determine the size of the borehole and length of pipe. HDPE pipe is relatively inexpensive and geothermal kits are oversized when it comes to the linear feet of ground loop pipe (700 per loop). The pipe should be placed ensuring the pipe is below the frost line about 6-8 feet deep. Based on these facts, Morledge Hall should have about 700 feet of ground pipe per loop (two loops like Orchard Hall totaling 1400 feet) and the depth should be about 7-8 feet below the ground.