The energy consumption of a heat pump in winter depends on various factors, including the type of heat pump, the outside temperature, the insulation of the house, and the desired temperature level. Here are some general considerations:

1. Type of Heat Pump:

   • Air-to-air and air-to-water heat pumps draw heat from the outside air. At lower outside temperatures, the efficiency of these systems may decrease, resulting in higher energy consumption.

   • Ground-to-water and water-to-water heat pumps, which extract heat from the ground or water sources, generally have a more consistent efficiency even at lower outside temperatures.

2. Outside Temperature:

   • The efficiency of a heat pump is often highest at moderate outside temperatures. At colder temperatures, the heat pump has to work harder to extract heat, which can increase energy consumption.

3. Insulation of the House:

   • A well-insulated house reduces the heat demand and helps the heat pump operate more efficiently. A poorly insulated house can result in higher energy costs because the heat pump has to work harder to maintain the desired temperature.

4. Desired Temperature Level:

   • Setting a higher indoor temperature requires more energy from the heat pump. An efficient approach is using low-temperature heating systems, such as underfloor heating, because heat pumps perform optimally with these.

5. System Design and Efficiency:

   • Modern heat pumps are designed to operate efficiently even at lower outside temperatures. It is important to choose a heat pump with a high seasonal coefficient of performance (SCOP/SPF) for better performance in winter.