How It Works

The Panasonic Energy Saver uses air-source heat pump technology. A heat pump is an electrical device that extracts heat from one place and transfers it to another. The heat pump is not a new technology; it has been used around the world for decades. Refrigerators and air conditioners are both common examples of heat pumps.

Heat pumps transfer heat by circulating a substance called a refrigerant through a cycle of alternating evaporation and condensation. A compressor pumps the refrigerant between two heat exchanger coils. In the outdoor unit coil, the refrigerant is evaporated at low pressure and absorbs heat from its surroundings. The refrigerant is then compressed on its way to the indoor unit coil, where it condenses at high pressure. At this point, it releases the heat it absorbed earlier in the cycle.

A diagram of a heat pump: 1) condenser coil 2) expansion valve 3) evaporator coil 4) compressor

The efficiency does decrease with temperature because it is more difficult to extract heat from cooler air. This graph shows how the efficiency is dependent on air temperature. Note however that you should only need auxiliary heating at temperatures below minus 5 degrees C, which we rarely experience in the UK.

This ability to absorb heat from the surrounding out-side air and send that inside to heat up your house can be highly efficient.

The Panasonic Energy Saver can produce as much as 4.2 kW (kilowatt) of heating energy from 1 kW electricity supplied.

As a comparison an electric radiator produces exactly 1 kWh of heating energy from 1 kWh supplied. The best condensing gas boilers produce up to 0.8 kWh per kWh of gas supplied. An oil fired boiler delivers similar efficiency.