What makes Econergy hot water heat pumps so efficient?

Econergy hot water heat pumps use electricity to drive a heat pump cycle, which takes the energy in the surrounding air and transfers it into the water. The process is quite similar to how a refrigerator or air conditioning unit operates, except the technology is harnessed to produce a steady stream of reliable hot water.

Co-efficient of performance (COP)

With the Econergy hot water heat pump, the COP is defined simply as:

Heat Pump COP Formula

kW output / kW input = COP

at 15°C ambient (air temperature) and 60°C water (the temperature of the water being produced).

The co-efficient of performance (COP) tells you how many times more efficient the Econergy hot water heat pump is at standard conditions than an electric hot water cylinder. Econergy measures the total electrical energy consumed when calculating COP, not simply the compressor electrical energy, so you know exactly what your cost of electrical energy is relative to hot water used.

‘Top down’ heat pump water heating

Unlike gas hot water or electric hot water cylinders, the Econergy hot water heat pump uses innovative new technology to heat the tank from the top down.

This means that you get usable 60°C water within minutes when starting from a cold tank – for example, when you have returned from a holiday.

Also, the unit is designed to produce 60°C hot water on a continuous basis and does not need an electric element to ‘boost’ the temperature to 60°C.

Easier on the environment -Ozone depletion potential

Econergy hot water heat pumps use zero ODP R134A refrigerant. This eliminates the possibility that damage to the ozone layer could occur during or after manufacture. The units are factory sealed, eliminating the possibility of leakage of gas.

Greenhouse gas emissions

These are primarily CO2 released into the atmosphere as a result of the burning of non-renewable fossil fuels (coal & gas) during electricity production. Installation of an Econergy hot water heat pump reduces greenhouse gas emissions by approximately 70% compared with a standard electric water heater. This equates to a 1.8 tonne reduction in CO2 emissions per year for an average New Zealand household*.

*Based on a 0.6kgCO2/kWh generated as quoted in ‘MEPS & Alternative Strategies for External Power Supplies’, Punchline Energy, Feb 2007. Average hot water consumption 210L per day.

Solar Mode (Optional)

Solar mode is an optional time-clock software update that can be installed during production to optimise the operating time for photovoltaic (PV) solar power systems. The heat pump will use its lower tank sensor for regular operation during specified daylight hours to do a full cylinder reheat. Outside of the timed hours, the upper tank sensor is used (solar mode only works with two sensor systems). When the available hot water at the top of the cylinder gets low the heat pump will switch on for one hour or until the top sensor is satisfied there will be a limited supply of hot water available in the morning.

If you would like more information about solar in off-grid systems, visit powerstation.nz