Will a heat pump still work and offer savings on energy costs when the air temperature is around -5 to 1C?
Answers:
Do you mean the exterior ambient temp?, if so yes it will.
Other answers:
your thermostat will work to a given temp,say 1c and go off after warming the room or place that the thermostat is in place
your thermostat will work to a given temp,say 1c and go off after warming the room or place that the thermostat is in place
A heat pump will theroretically work down to absolute zero.
A heat pump is basically an air conditioner that runs in both directions. It cools in the summer and heats in the winter. If you want inside your home to be at 72 deg F, then it probably will not work very well. Generally all heat pumps come with strip heaters (resistance) that supplement the heat pump.
no
Heat pumps can be used in a variety of ways. The way in which they tend to be used in the UK is through pumping the heat from the ground rathrer than the air. By having a network of pipes running underground through the garden into the underfloor of the ground floor for example you can obtain heat in the air temperatures you describe because the core temperature of the ground remains higher than that of the air at a level of just six to eight inches depth. The earth effectively 'stores' the heat from the day allowing heat to be extracting at night for example. Heat pumps are an effective method of providing underfloor heating for the ground floor of new properties, but the costs of retro-fitting an existing property tend to make alternative renewable technologies such as wind turbines or photo-voltaic electric roof tiles more ffective options for micro-generation on existing properties.