Geothermal Heat Pumps in Our Schools, Colleges & Universities
Primary, secondary and post-secondary learning institutions may experience some intermittency in their classroom use, but plenty of their buildings have consistently high heating or cooling loads that demand the greatest level of efficiency possible. Someone you know has complained about schools being too hot in winter and over-cooled in summer, and maybe you’ve even experienced it yourself.
The days of the central boiler/chiller plant are over, where the inherent inefficiency of large capacity units do not match building loads very well. There’s always some heating going on and there’s always some cooling, too. Trouble is, when you want more of one, you cannot get it from the other. Huh? A steam or hot water circuit from a central plant and a chilled water circuit from separate equipment in that same plant do not interchange with each other as they make their way out to buildings and their rooms, and back again to the central plant. Localized thermostats dictate whether either is provided to interior space. Let’s look at how that heating and cooling might change with a geothermal heat pump system.
A single, common loop connecting an underground heat exchanger to multiple heat pumps inside a building could provide greater options in heating and cooling. When one space wants heat, the heat pump concentrates energy from the ground loop to provide it. And, if any other space connected to that loop called for cooling, some “waste” heat would enter the loop. Under such conditions, the two subject rooms on the common loop could trade thermal energy between them. But when all spaces call for heating or cooling, the underground portion of the common loop could still provide all of it. If any space’s heat pump was set to follow non-occupancy parameters, all that energy use could be avoided (but re-activated at a moment’s notice without an efficiency loss).
Since schools are permanent, publicly-funded buildings, they will incur heating and cooling costs in perpetuity. Therefore, any shift to greener and more efficient HVAC equipment (like geothermal heat pumps) would reduce utility expenses in the operating budget for a greater period of time. Geothermal heat pump equipment lasts longer than any comparable system, and can insure that institutional buildings experience the lowest possible life cycle costs.
Some school districts see their mission to support sustainable environments as an opportunity to incorporate building heating and cooling technology into their curriculum. A growing number feature mechanical rooms with large-print signage on pipes, pumps, and air handlers, and large “truth windows” that let visitors observe an operating system in use from the safety of public space. With greater savings in heating and cooling costs, all schools have more opportunity to put those (previously lost) dollars to work in their core mission of education.