Building Electrification & Moving Towards Energy Decarbonization Building electrification refers to using electric technologies Rick Alfandre, AIA LEED AP BD+C Alfandre Architecture, PC
instead of combustion-fueled technologies to supply the
alfandre.com 845.255.4774 ralfandre@alfandre.com
domestic hot water, as well as electric or induction stoves for
comforts of a modern building. An electrified building typically uses electric heat pumps for space heating, cooling, and cooking. Every major end use for fossil fuels in buildings is ready to be electrified with current technologies.
E
lectrification supports the long-term goal of
Electric resistance heat is 100 percent efficient at
building decarbonization. By designing and
converting electricity into heat. A heat pump provides at
constructing buildings to harmonize with the grid
least two to three units of energy for every one unit of
we will reduce overall greenhouse gas emissions. Heat pump technologies use energy in highly efficient ways and, therefore, save building owners money. Heat pumps—whether ground-source or air-source—are basically air conditioners that can be run in reverse to provide heating as well as cooling. Air conditioners (and refrigerators) make a space cooler by extracting heat from it and releasing the heat in a warmer place. The key to this magic is the refrigerant, a fluid that changes from a liquid to a gas at ambient temperatures. After absorbing heat, the gas moves through a mechanical compressor that squeezes the heat back out.
energy consumed. Efficiency is often measured as the annual “coefficient of performance” or COP. The COP of a system is the relative measure of how much energy is delivered compared to how much energy is used. Most air source heat pump systems have an average annual COP of over 2.5. This means that the system is 250 percent efficient. Fossil fuel heating systems range from 80-95 percent efficient, at best.
Heat pumps systems include: Ground source heat pumps (GSHP), which extract energy from the ground by tapping the relative constant temperature of the Earth from about 5 feet, or more, below the surface. Ground-source heat pumps have some great environmental advantages over other heating and cooling systems. They use the consistent temperatures within the Earth as a heat sink to provide energy-efficient heating in the winter and cooling in the summer. In commercial applications most GSHP systems rely on a field of drilled wells fitted with a closed loop set of tubing through which fluid flows. By releasing building heat to the cool earth, rather than into hot outdoor air, GSHPs cool more efficiently than air conditioners or air-source heat pumps.
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