Heat exchange (or heat pump) technology has the potential to dramatically change the way we heat our water. The basic principle works like a refrigerator in reverse, using a non-CFC refrigerant to take heat out of the air and transfer it to a coil wrapped around inside a water tank - water is pumped through the tank and absorbs the heat captured from the air.

This technology is almost as efficient as a good quality solar water heater like evacuated tube solar, providing about 75% of the total energy needed for water heating from the heat energy in the air (evacuated tube systems will provide about 80% of the total energy needed from the Sun).

The big difference is in the installed cost of these units. Heat pumps are much cheaper to install as there is no need to run copper flow and return lines to a solar collector on the roof.  

Whilst the technology has been around in various forms for more than twenty years, it is only now starting to be successfully developed and exploited

• Has almost twice the efficiency as comparable "flat plate" solar systems*
• Is one of the most energy efficient water heaters available and
• Can produce more hot water for less than any other comparative system**

* For domestic hot water heating in "temperate climate" cold weather
** Based on large demand e.g. 305 l/day (55MJ/day Sydney) or more

Comparison of the energy cost to make hot water
for a typical family of four over a one year period

* Energy Saving Comparison report

* Siddons Solarstream Heat Pump brochure

* Installation Manual and Warranty

* Renewable Energy Certificate (RECs) application form