Using a Heatpump hot water system
With over a million homes already using solar in Australia the amount of excess energy going back to the grid is enormous. This energy can be put to better use.
The standard rate of supply changes from region to region but the one thing that remains constant is the fact that it is always going up, not down. Export energy pricing is not stable many parts of NSW and is anywhere between 6c and 21c p/kWh, why export? It’s not worth it.
Installing a timer on the Heatpump hot water system so that it runs during the day when your PV plant is producing free energy is a logical solution. The Heatpump hot water system runs off a standard power point or 10 amp circuit so nothing special needs to be installed. As the PV plant is sending power into the house the Heatpump hot water system will heat up and store the hot water.
The timer prevents the Heatpump hot water system from turning on during the night keeping it quiet and ready for the next morning’s free energy. You have a big family, or you have gusts staying for the weekend? The timer can be manually operated or adjusted if you need it to run longer.
30-40% of a household’s energy goes to heating water.
If you have a gas storage/instant hot water system. OK during the warmer months 80% of you gas bill is hot water during the colder months (if you have gas heating) will be more like 30% averaged out 55% of you gas bill is hot water (without heating 75%)
If you have an “Off peak” electric hot water system which is on average about 12c kWh and will use 16-25kWh per night to heat up. Export electricity is between 6c and 21c kWh and a Heatpump will use 4-6 kWh to heat the same amount. Or in layman’s terms about 25% of the kWh’s used.
Economics.
If you have PV solar panels on the roof already and you are exporting over 350kWh per quarter to the grid on average. Install a Heatpump hot water system. Your energy bills gas and electric will improve.
Example, Joe and Martha a newly retired couple have just downsized from a large family home to a smaller three bedroom cottage. The house has a gas storage 135 litre and gas cooktop. They use air conditioning for heating and cooling. They are on the conservative side and use about 15-18 kWh per day of electricity. Their gas bills vary from $200.00 in summer to $700.00 in winter. If we install a 2-3kW PV system we can cut their power bill by 30-40% (their daytime use of power) this still leaves 2-3 kWh of electricity exported at little to no value. Take out the gas storage 135 litre and replace it with a 300 litre Heatpump which uses that 2-3kWh of energy per day to heat water. They eliminate 75% of their gas bill and 40% of their power bill. The return on investment is reached much sooner as you have 100% of the renewable energy used at the maximum return. An elegant and logical solution.
The bottom line: instead of paying around $1450.00 per year for gas to heat water, someone with a medium rooftop solar system can use their excess electricity, which their retailer values as little as $84.00 per year. The result is that the homeowner has all the hot water they want and they are $1450.00 per year better off.
in higher demand applications and cold ambient conditions; you will enjoy hot water all year round. Built locally to the tough Australian conditions, these tanks have been tested and designed to operate with mains water pressure.
