Householders who combine Economy 10, the differential tariff developed to encourage consumers to use energy during off-peak times, with an air source heat pump and Sunamp Stack are making significant savings. Find out how we saved one Borders household £943 a year on fuel bills by storing heat at off-peak rates to be used on-demand when it is most needed.

According to the Annual Energy Consumption in the UK, the paper published annually by the Department for Business, Energy and Industrial Strategy, space and water heating account 80 per cent of final energy consumption in the domestic sphere.

The Renewable Heat Incentive was created by government to increase the uptake of renewable heat to meet this demand. One of the key technologies it supports is the Air Source Heat Pump (ASHP), paying around 10 pence per kWh (up to a maximum of about £1400 per year) for seven years for domestic household installations. Commercial installations receive a lower payment per kWh over 20 years.

The air source heat pump intakes cold air and, by using a compressor like those used in refrigerators, is able to efficiently upgrade this low-temperature air from outdoors into high-temperature heat to use inside the building to run radiators, or be stored in a Heat Battery to later provide hot water or space heating. A single kWh of electricity is used by an ASHP to capture, upgrade and deliver 2 – 3 kWh of heat.

Economy 10 electricity was developed to encourage consumers to use energy during off-peak times by reducing costs, creating three different time periods per day – in the wee small hours of the morning, the mid-afternoon and late evening – when electricity is as low as half price. This is like getting a two-for-One offer on electricity for ten ‘off-peak’ hours per day.

The only problem is that, by definition, these hours are truly ‘off-peak’ – they do not coincide with when you most need heat or hot water. That’s where the Sunamp Heat Batteries provide the solution, storing the heat produced when it’s cheap during off-peak hours into Heat Batteries which can then be used to heat radiators and provide plentiful hot water at any time on-demand. Sunamp Heat Batteries can store enough heat to supply all the hot water required for washing and central heating in the home.

What’s more, heat batteries make heat pumps much more powerful. A common complaint with heat pumps is that they come up to speed slowly and it can take half an hour or more to heat up the radiators when the heating is switched on. With Sunamp Heat Batteries, stored heat can be discharged to radiators at a prodigious rate resulting in hot radiators in 90 seconds or less.

Sunamp’s Heat Batteries are the key enabler of this ‘time-shift’ to harness 2-for-1 Economy 10 electricity with the typical two and a half-fold gain from the air source heat pump, achieving up to five kWh of heat energy for the cost of just one full-price unit of electricity.

The technology has been proven over the last five years in trials funded by UK government in around a dozen homes, where it has replaced night storage heaters, coal fires and gas boilers. The first private customers are delighted with their purchase.

Even homes that currently heat with gas – widely considered to be the unbeatably low-cost fuel at around one third of the electricity price – can save around 50% of their annual costs by switching to Economy10, and a Sunamp air source heat pump + heat battery package. At last, there is an economically attractive and super-green alternative to gas.

Combining the Renewable Heat Incentive of up to £1400 per year, fuel cost savings of up to £1000 per year and very attractive package pricing from Sunamp – as low as £9999 including VAT fully installed – means there is no reason to hesitate in ditching fossil-fuelled heating in favour of renewable heat.

How much can I save?

Click here to find out how we saved one Borders household £943 a year on fuel bills

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