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"According to Cllr Hearn there is one at Chiswick Baths.  I don't know if it is a super quiet or super noisy one. I presume it is an air source one."Yep - Chiswick New Pool Edensor Road. Discretely hidden behind a wooden screen. As it happens I checked it out again last week. I lead an exciting life. If you stand next to it you can hear a noise that I think is the fan. Stand ten feet away and you would not know that it was there but then I am getting a little deaf in my old age.I know that no one likes a smarty pants BUT. We had a ground source heat pump installed when we built our new home nine years ago. I have been fascinated with this kind of technology since I was a mere whipper snapper and prevailed on my builder father to visit the Alternative Technology Centre in Machynlleth. The Cretan Wind Mills and earth closets remain indelibly printed on my mind.To be quite honest the ground source heat pump was a bit of a disappointment. The mechanism was overly complicated for a bloke like me and the instruction manual was almost incomprehensible. We had a maintenance contract arranged through the supplier but they went bust - only to reappear with a slightly different name.It was incredibly hard to find a qualified service engineer. Some could do the electrics and not the plumbing, others could do the plumbing and not the electrics.We persevered with gritted teeth but ultimately we decided that the system had been underspecified and replaced it with an air-source heat pump. No problems to date. As the technology advances it becomes quieter. That said you can pay a little more and have a quieter model.Ultimately I think that any heat source pump (air or ground) is most environmentally friendly when at least some of the time it is powered by electricity from photo-voltaic panels on the roof of your own home. I was not brave enough to do this although I had planning permission to do it - the panels would only have been 80% efficient because of the position of my roof. As Michael Caine might say "not many people know that".Down the line as the planet gets hotter you will be able to use the air-source heat pump to cool your house in the summer. As people often say - it is only a fridge in reverse. Not quite true but close enough. Definitely something I will be looking into in my dotage.      When I last researched it, retro-fitting a ground source or air source heating system into an existing property was by and large a bad idea. Ideally a heat pump should be driving under floor heating in a home insulated to today's high standards. Making the system run conventional radiators was also incredibly inefficient. A bit like the paddle wheels and sails that Brunel fitted to his screw propeller powered Great Eastern (I actually typed Greta instead of Great - it always pays to proof read). You will have to find somewhere else to dry your socks.  Living with under floor heating takes a bit of getting used to but it is now second nature. Who does not like a house heated to a constant temperature? It is not a great idea to open the windows in the cold weather but that is true for any conventional heating system- why not just turn the thermostat down if you are too warm?Can I put in a word for electric underfloor heating. Relatively easy to install and maintain. Very flexible. Great for those who appreciate a warm bathroom in the morning.But before you do anything else insulate your loft and possibly your walls. Money spent on insulation is seldom wasted and you never know what the previous owner has left in the loft.We also flush our toilets with water harvested off the roof but that is another story ....

Cllr Sam Hearn ● 35d

Yes and a lot of people live underneath a flightpath and have stopped or hardly notice the planes!  The airport has been there a long time.  These machines make a noise, they are not silent yet... but who knows?  We live in London - not in the countryside. They are obviously better with newer better insulated and ventilated homes. I don't suppose most people will make the changes until they need to replace their gas boiler but most will want to have an idea of what their options are and what they are facing.A lot of people didn't change to condensing boilers until they had to because of changes to the Building Regulations.The Renewable Heat Incentive grant will end soon.  The New Green Deal was pulled after there were a lot of complaints of people being unable to find trained installers within the time-frame.  It looks like finding people with the technical expertise is still going to be a problem. It is so important that the system is matched to the home.Many houses have been poorly converted into flats with a lack of thermal and acoustic insulation and fire separation between dwellings.  How easy is it nowadays to get an off-shore freeholder to agree to and cough up for loft insulation?Interestingly landlords do nowadays have more responsibilities than they did for insulation as rented accommodation should have Energy Performance Certificates.With terraces we can hope that there will be more work on local initiatives. Yes, there is talk of running hydrogen through the gas pipework... And green hydrogen is better than blue but it doesn't sound like it is close to happening. Meanwhile there are electricity companies now who will buy the excess that you make from your solar panels and lease you an EV car.

Philippa Bond ● 36d

I'm surprised he responded and so quickly not that we don't is his response Sorry the way it might be pasted hereHeat pumps operate on electricity which costs about 26p per kWh. So if the efficiency of the unit is 4 then (400%) it will take 26p to transfer 4 kw of free heat from outside per hour. Gas costs about 4p per kWh so it would cost you 16p to put the equivalent 4kw into the space per hour. So on cost of operation alone it’s cheaper use gas.The carbon dioxide saving of heat pumps is where the government is pushing the green banner. Electricity currently has carbon intensity of around 0.5kg co2/kWh and gas is around 0.25 kg co2/kWh so getting 4 kW of heat the electricity is 0.5 kg co2 and the gas is double at 1 kg co2/kWh.But that’s only half the story.Gas boilers operate at 80 deg c and heat pumps around 40 deg c. Heat pumps are designed for well insulated homes not old homes with gas boilers. If you try to run a heat pump onto an existing radiator system the radiators will need to be larger to get the same input.So you need to insulate to high levels if you are not changing the radiators.Next is the location of the heat pump outside and consideration of noise and neighbours Next is the operation of heat pumps. In depths of winter they will go into defrost cycle for 10 minutes or more during which no heat will be provided.So in summary, good for new build highly insulated but for existing very debatable.The government is only covering grants for 90,000 homes.Keep with existing gaos boiler and wait for the natural gas/hydrogen mix that will come up the pipe in the future xhosa

Julian Pavey ● 36d

I think that £15,000 - £20,000 is more realistic costs to install an air source heat pump in  a medium sized Chiswick house (say 1,200 sq ft) including upgrading the radiators to fan assisted radiators.So, a grant of £5k, plus the saved cost for a gas boiler £3k = £8k.Leaves a £7k to £12k shortfall. But... instead of costing say £800 a year to heat a house with gas, if wholesale gas prices stay where they are it will cost maybe £2,400 - £3,000.Then again, electricity prices have also doubled (but not quadrupled), so it will probably cost about £1,500 now to run a heat pump.So the saving in running costs (assuming energy prices stay where they are) may be around £1,000 - £1,500 a year for a heat pump over gas (until the recent increases, the running costs would have been about the same, because gas was a lot cheaper).So a heat pump may give a saving of say at least £1,000 a year in running costs (and less maintenance, etc). So the return on the investment on the extra cost is between 8% - 14% p.a. Which is a good return for someone who has spare cash sitting in the bank, or can borrow more cheaply than that.  Payback in full would be less than 10 years. Then you are in profit.This is a very rough and ready as a calculation.  The problems are: (a) many people don't have the spare cash lying around, or can't borrow that cheaply; (b) it is likely that gas prices will reduce from the extraordinarily high levels after a year or so (particularly if we address the problems caused by leaving the EU Internal Energy Market, which have driven up UK gas prices by far more than within the EU), so in the longer term, although gas is likely to increase more than electricity the difference in overall costs may reduce. So there is still an economic argument to be made for heat pumps in many cases. None the less, the government needs to do much more, so that this is not just a subsidy for the rich.  They may do this in a negative way, by switching the green levy from electricity onto gas to make gas more expensive (which has a logic, but will cause massive problems for many people whilst gas prices remain as high as they are).

T P Howell ● 38d