Going Green doesn’t have to cost the earth!

24th June 2021

Meet the expert! - Richard Bray, Beresfords' Development Director discusses why going green doesn't have to cost the earth.

I have recently been advising a client on a scheme for 19 new apartments in London, where in order to improve air quality and make London zero carbon by 2030 the mayor has effectively banned traditional gas fired boilers for new build developments. This has led me, my clients and their Architects into the dark and mysterious world of renewable energy and specifically Air Source Heat Pumps (ASHP).

It is not something that I would have ever considered for myself but having been sold on the benefits, I wondered if it might also be a good idea for my own home.

I have a 200 year old 3 bedroom detached cottage, with a modern extension. My first thought was that my house would be totally unsuitable for such a system and a trusty oil boiler could probably chug along for a few more years (despite needing an engineer at least twice a year to keep it going).

Actually I was wrong, our extension has underfloor heating and this was perfect for such a system, and although the old part of house has no insulation in the walls that was fine too, it would need bigger radiators as ASHP's run at lower, but consistent temperatures.

ASHPs are basically an air conditioning system working in reverse. They use very established and reliable technology (think refrigerator) to convert heat from the outside air into heated water that is then used to heat a water cylinder or a central heating system in a very efficient way.

I alluded to the fact that our current boiler is very experienced in what it does, or frankly quite knackered. To replace it with a new, more efficient oil boiler is c.£4,000. Ouch.

How does this compare to the ASHP? This is where it gets a bit complicated, as there are some great incentives available (until March 2022) from the government in terms of grants.

I won't go into the details of this (links in table below), however based on the quotes I received this is how it all compares financially over a 7 year period.

It should also be noted that the ASHP cost includes new hot water cylinders and radiators, whereas the boiler cost does not.

The grants are due to end in March 2022 (with works needed to be complete by then) and the government did not renew them in the last budget so there is now a very limited window to take advantage of these incentives.

Using a standard energy tariff (where approximately 20% of power is generated by renewables) switching to an ASHP reduces net carbon emissions by 69%. This can be increased to 100% by opting for a greener renewables tariff from your energy supplier. Scottish Power, amongst others, for instance guarantee that all their domestic tariffs are from renewables.

I think it's time to say goodbye to Bertha, the boiler, and say hello to Hetty, the heat pump.