15 Nov How Do Heat Pumps Perform In Nova Scotia’s Cold Weather?
Heat pumps are leading examples of how far engineering technology has advanced to provide energy efficient heating using electricity. Instead of using fuels to create heat, they harvest the existing heat from the outdoor air, concentrate it and bring it inside. Both central heat pumps and ductless mini split systems provide at least three to five times the heat for the same amount of energy as electric resistance heaters do.
Heat Pump Limits
Since heat pumps extract heat from the air, their efficiency depends on outdoor temperatures. Less heat in the air meant that the heat pump has to work harder to collect the available heat.
High-end efficient machines can extract heat down to temperatures as low as -20°C and even lower in some instances.
What is Heat Pump Efficiency?
The heat pump industry applies two efficiency ratings to heat pumps. The first is the HSPF (heating season performance factor) and the second is its COP (coefficient of performance). Of the two, the COP is easiest to understand and apply to this region.
Electric space heaters, furnaces, or baseboard heaters all rely on electric resistance to generate heat. They create one unit of heat for every watt of electricity they use, which gives them a COP of 1. Heat pumps, on the other hand, in optimum conditions create at least three units of heat for every watt they use, giving them a COP of 3 or 300 percent.
The most efficient heat pumps have COP ratings of 5 and more when measured at optimum temperature. As temperatures fall, heat pumps have less heat to work with, and their COP ratings fall. Electric resistance heating systems always have a COP of 1, regardless of outdoor temperatures.