Speaker Dr Brenda Boardman, from the Environmental Change Institute at Oxford University Centre for the Environment, said she was alarmed at the number of new flat developments in London with electric heating installed.
She said electricity was still the energy source associated with the highest level of carbon emissions and this was unlikely to change for another 20 years.
She told the conference: “Do not put in electric heating or anything that uses electric heating in quantities unless you have no other choice or if it is extraordinarily low demand, otherwise you are making matters worse.
“If you have a client wanting to put in electric heating, speak to them about climate change. I expect this will become quite an issue for you.”
But Chris Davis, head of renewables at electric heating specialist Dimplex, questioned Dr Boardman’s position. “I am fundamentally opposed to those who say ‘do not use electricity’ as they are not taking the long-term view,” he said. “We are looking at a 50-year window where we will see a decarbonising of the grid.”
He predicted factors such as the uptake of renewables, increased efficiency and the development of new nuclear power stations would achieve this. He also questioned the reliability of gas supplies.
Mr Davies insisted that low-carbon technology such as ground source and air source heat pumps would massively improve the efficiency of electricity use because the heat drawn from the air or ground is three to four times the energy content of the electricity used.
The Good Homes Alliance has said electric heating is becoming increasingly attractive to developers because a “loophole” aimed at helping properties not on the gas grid has make it easier for properties using electric heating to attain Level 3 or 4 of the Code for Sustainable Homes. Meanwhile, private and social housing landlords are attracted to electric heating systems because of lower maintenance costs and the fact an annual safety check is not mandatory – unlike gas systems.
But according to Department for Communities and Local Government figures released last year, grid electricity still produces more than twice the carbon emissions of mains gas with grid electricity generating 115 grams of carbon per kiloWatt hour (gC/kWh).
Dr Boardman said: “It is quite difficult for owners and developers of the high efficiency properties which we are starting to see where the quantity of heating needed is very small – there is a strong temptation not to put in more capital intensive equipment like a gas boiler when you can go for electric heating. That might be a good policy to keep the cost down, but it is not a good policy for climate change.”
Dr Boardman believes micro-Combined Heat and Power (CHP), community CHP and solar thermal technology all need to be used appropriately to reduce radically the carbon emissions of homes.