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How to heat water, not the planet

The energy needed to heat water has to come from somewhere.  The more renewable the energy is, the less greenhouse gas emissions are created.  Plus, the more efficient the technology is, the less energy that is needed.

A Reclaim heat pump or Apricus solar hot water system will provide up to five times as much heat output compared to electricity input.  The associated climate change emissions therefore drop enormously.

Compare this to a gas water heater with relatively low operating efficiency and burning a fossil fuel (natural gas or LPG) which is completely non-renewable.

Ways to reduce the environmental impact of your hot water

  • Choose a technology that minimises fossil fuel use
  • Choose a technology that has high energy efficiency
  • Compare greenhouse gas emissions kgCO2e/year*

How the green house gas emissions compare.

comparision of environmental impact of hot water heating technologies

* Calculated using kgCO2e/kWh factors from MfE Measuring Emissions, 2019, assuming average annual hot water energy use of 3,995 kWh for family of four.  Reclaim heat pump with 4.7 COP, Apricus solar hot water reduces electricity use by 75%, published efficiency figures for gas water heaters, electric cylinder 100% efficient.

Other environmental considerations for heat pumps and solar

To heat water using solar energy the most efficient direct system is to have a high performance solar hot water system, like Apricus.

Alternatively, combine a solar PV system with a Reclaim CO2 heat pump and you will get 5 times more heat energy in your cylinder from the electricity you generate.  This means your PV electricity will go a lot, lot further for the same system size.

The best heat pumps available have the highest co-efficient of performance (COP).  Reclaim for example has a COP of 4.7.  Less energy use reduces the environmental impacts from the electricity generation.

In addition, heat pumps use a refrigerant to operate.  All refrigerants have a global warming potential (GWP), a measure of the impact on the climate if the refrigerant is released to the air.  The higher the GWP the worse the impact’ so leaks during their operating life or at end-of-life disposal are an important, although hidden, environmental impact.

Carbon dioxide (CO2) has a GWP of 1 and is the basis on which all other refrigerants are compared. CO2 is used as the refrigerant in Reclaim Energy heat pumps and a small number of other units.  Most other heat pumps use the refrigerant R134a which has a GWP of 1,300.  If 1kg of R134a, a standard refrigerant load in a hot water heat pump, is leaked in to the air it is the equivalent of emitting 1.3 tonnes of carbon dioxide.

Learn more about CO2 hot water heat pumps.

Learn more about solar hot water