Increasing the Efficency of your Range
Range cookers such as Agas and Rayburns, when fired by dated wick oil burners, typically provide only £40 of heat for every £100 of fuel bought, the remainder being wasted through the flue. This compares to £85 of heat per £100 of fuel from a typical central heating boiler driven by a pressure jet burner. Some modern range cookers already have jet burners and the better models have separate burners for cooking and heating. We would be happy to check which type you have, if you are not sure.
Added to this, wick-burner ranges waste more energy because they burn fuel over a 24-hour period, and are often left running in summer, producing significant amounts of unnecessary heat. This contrasts with a conventional cooker which uses fuel only when it is being used, typically a maximum of two hours per day.
According to fuel consumption figures published by Aga, a four-oven oil-fired cooker-only Aga consumes about 2,650 litres of oil each year if used as the sole cooking device. At 45p/litre this costs over £1190 per year. This is nearly 33 times the UK annual average amount of energy used for household cooking.
Burning this amount of oil emits 7,100 kg of carbon dioxide/year, over 50% of the average household’s emissions including transport. Whilst a range cooker provides some heating to the room as well this is much more efficiently provided by a dedicated central heating boiler with effective heating controls.
If your range cooker is a wick burner type we recommend that you replace it with a conventional cooker, whilst letting a central heating boiler deliver heat in your home. The next best option would be to modify the range to operate with a modern jet burner. No funding is available for this through the Green Deal or ECO but it can provide a good return on your investment.
Below is a table showing the savings generated by switching from an Aga OE range cooker to an electric cooker (as an example), allowing for the increase in central heating costs to compensate for the loss of room heating by the range (complete removal of the range is the best option).
Investment: From £200 (cooker only)
Financial savings: Over £700 per year
Carbon dioxide savings: Over 5,600kg/year
Making Your Range More Efficient
If, however you wish to retain your Aga there is a way of improving its efficiency. Snughome Cookers in Wrexham convert range cookers from wick burners to pressure jet burners. Their website can be accessed at: www.snughomecookers.co.uk.
Conversion cannot only double the range’s efficiency, but also the heat becomes more controllable and can be switched off overnight, reducing energy costs still further. Pressure jet burners do cause some noise during operation, just as a normal central heating boiler does. Also, because the range is designed to be a high inertia system, the energy saving is unlikely to be more than about 40% compared with a potential saving of around 80% if you switch to using an electric cooker. The cost of conversion is from £2,000, but this could be repaid in four years.
Savings from converting an Aga to a jet burner (second best option)
Investment: From £2000
Financial savings: Up to £480/year
Carbon Dioxide savings: Up to 2,840/year
If you do not favour either of these options, then we recommend that during the summer you switch off your range and use an alternative cooker.