Supplemental home heating for the cost of running a light bulb
Homes are heated by a number of different fuel sources, most of them based on fossil fuels. The Attic Heat Harvester System supplements, i.e. partially replaces, existing 'far more expensive to use' home heating systems reducing their use and your heating cost.
If you use a home heating system during the year and your home has a moderate or large attic with a sunny roof the Attic Heat Harvester System replaces fossil fuel by using free solar heat instead and can reduce your annual heating cost in the UK typically by from 5 to 20%. In many sunnier countries annual heating cost savings can be far higher. Because the system is incredibly efficient the heat produced costs almost nothing.
The UK 2012 average annual fuel cost for space heating and hot water for a three bed semi-detached well insulated home are shown in the table, space heating cost is typically ¾ of the annual fuel cost.
|Type of boiler||Average annual
fuel cost *
space heating cost
|Attic Heat Harvesting
annual cost saving
|Wood||£510||£383||£19 to £77|
|Electric||£870||£653||£33 to £131|
|Non-condensing gas||£730||£548||£27 to £110|
|Condensing gas||£490||£368||£18 to £74|
|Gas LPG||£830||£623||£31 to £125|
|Non-condensing oil||£1,100||£825||£41 to £165|
|Condensing oil||£740||£555||£28 to £111|
The space heating cost saving for homes with old heating systems and for larger and for poorly insulated homes will be considerably greater.
A prototype system installed in a home near Edinburgh, Scotland, produced 600 kWh during 2012. The total 2012 system operating cost was just £4.51 giving a cost per kWh of less than 0.8p. Product testing and enhancement, which is now complete, continued during 2012 further improving system performance. Between March and June 30th 2013 the improved system produced more than 620kWh exceeding the 2012 total!.