Info article: Are heat pumps cheaper to run than mains gas? The answer is no...

richardc1983

Just seen the below article, there is a target of 600,000 heat pump installations by 2028! Whilst I am all for supporting heat pumps as the main source of heat, until they bring down the cost of electricity per kWh it is not worth the investment and extra running costs over mains gas. Gas is very cheap so if you have a high efficiency condensing boiler running on mains gas then you are better off with that for your heat than going for a heat pump.

A heat pump produces heat more efficiently and cleanly but the electricity costs more to do so: If we consider my own energy tariff that is a current fixed rate deal 1kWh of electricity costs 13p and the equivalent in gas is just over 2p. If we for argument's sake say that a heat pump is 300% efficient meaning for 1kw of energy used (13p) we are getting 3kw heat from it. On my tariff, for it to break even the heat pump system needs to be about 700% efficient.

A modern condensing gas boiler maybe 98% efficient meaning 3kw of heat generated by mains gas is costing about 6p a heat pump is double. Even the standing charge for gas is considerably less at 9p than electricity which is nearly 3 times as much at 23p.

Homeowners being sold heat pump systems over a new modern condensing boiler are being missold if they have mains gas. The number of people I have come across who have ripped out a condensing boiler and put one of these systems only for operating costs to go through the roof only to rip it all back out and start again is crazy.

If you are on mains gas and looking to replace an older gas boiler, fit a new gas condensing boiler, if you don't have mains gas and are using oil or electrical resistive heating (fan heaters, convectors etc) then fit some form of heat pump. Electrical resistive heating is 100% efficient. Meaning that you get 1kWh of heat out for every 1kWh you use, in my tariff example above that is 13p, so a 3kw fan heater will cost you 39p an hour to run whereas a heat pump will produce 3kw of heat for that hour using 1kw of electricity and cost 13p to do so. The equivalent 3kWh from mains gas is approx 6p.

https://www.acrjournal.uk/heat-pumps/uk-targets-600-000-heat-pump-installations-a-year-by-2028/

Cardew

There is another important point that needs to be considered if anyone is contemplating installing an ASHP or GSHP. Because to achieve reasonable efficiency a heat pump needs to have water to the radiators or under-floor heating(UFH) at low temperatures - 30C to 35C is ideal.  

This means that the heat pump has to run for very long periods every day - often running 24/7 - to maintain the required room temperature. Thus for properties where the occupants are out at work/school during the day it is necessary to keep the house fully heated, as if it allowed to cool down it takes hours to bring it back to the required temperature. In those circumstances with gas/oil/LPG CH, with their much higher heat output, it is sufficient to have the heating come on, say, 30 minutes before the occupants return home. Similary during the night, I suspect most of us are not too bothered about how low the temperature drops at night as long as we get up to a warm house.

matelodave

I note that richard seems to have a bit of a thing against Heatpumps as he's squirted this over the Forum in at least three different threads.

I'm not sure than anyone has ever said that they are cheaper to run than mains gas as they most certainly aren't especially with the price differential with mains gas although they are cheaper to run than LPG and possibly on a par with oil. Likewise they aren't as convenient as gas, oil or lpg. A lot depends on whether you have the option of mains gas or not or really feel that you'll be saving the planet by getting one. TBH going green hasn't ever been cheap.

Has he got an agenda or is he he just disgruntles because he's got one and it's not living up to expectations?

richardc1983

matelodave said:

I note that richard seems to have a bit of a thing against Heatpumps as he's squirted this over the Forum in at least three different threads.

I'm not sure than anyone has ever said that they are cheaper to run than mains gas as they most certainly aren't especially with the price differential with mains gas although they are cheaper to run than LPG and possibly on a par with oil. Likewise they aren't as convenient as gas, oil or lpg. A lot depends on whether you have the option of mains gas or not or really feel that you'll be saving the planet by getting one. TBH going green hasn't ever been cheap.

Has he got an agenda or is he he just disgruntles because he's got one and it's not living up to expectations?

Hey Dave,

I resent your comment above as this forum is a money-saving forum and many people who come here are either savvy with their money or really struggling financially and looking for advice. In these current times, many are losing their jobs but still having to maintain their homes and provide a warm environment for their family. As you know I have been on the forum a long time even writing a guide on ASHP in general as I am a big supporter of the technology in the right application. 

I have a multi split air con system at home that I use for cooling in the summer and supplemental heat in the winter. As has been the case for a long time many people are being sold heat pumps by dishonest installers on the basis that they "are cheaper to run than mains gas" this is not correct. It's great and warms the house up quicker than the radiators do due to how it delivers the heat but due to the unit cost difference, it is more expensive to run. 

I felt compelled to do a post on it (updating my original post at the start and putting it near the end due to the number of pages) as something that people need to consider as ultimately people ask "is it going to be cheaper than what I have now" I have recently changed energy supplier and didn't realise it was such a big contrast between unit prices. Back in 2010 my electric kWh price was 9p per kwh, now it is 13p, gas seems to be about the same. 

I work in the HVAC industry but I believe in being honest with people. I am coming across many people who even with a well installed system and it is setup for optimum operation it is still costing them double what the previous old outdated gas boiler (non condensing) cost them. These people are literally ripping out the heat pumps and going back to gas, this is giving the industry a bad name because the initial outlay and upfront cost for the heat pump system is more than a domestic gas boiler costs. 

Not sure why you would think I have an agenda when I am just making people aware that they need to be considering all these factors in the present time. There are many disgruntled people however who have been lied to, had the wool pulled over their eyes with a promise for a cheap running system, elderly people too afraid to put the heating on because of the high bills they have received yet received some sort of government grant to put these systems in and the installers flog these systems knowing that it's easy money to convince unsuspecting customers. 

I believe in being honest and I have always tried to put that across on here, also helping many members with existing problems some which are just setup issues. I remember a case on here many years ago where it was in Scotland (no gas) and all the issues they were having were commissioning issues. They had switched from oil heating and once the commissioning issues had been sorted they were enjoying the cheaper bills than what they had become used to. Heat pumps are fantastic pieces of kit that really do give you more than you put in BUT they have to suit the home they are being in and as this is a money-saving forum, at the moment if there is the option of mains gas, that will be cheaper for you to heat your home with, combined with a modern condensing boiler.  Even if it was not a condensing boiler the price of gas still makes it the cheaper form of heat. 

All I am doing is being honest, in these times people are making difficult decisions and at the moment most of us are doing what we can to save money as we do not know if we potentially will have jobs in the coming months. 

Rodders53

richardc1983 said:  I work in the HVAC industry but I believe in being honest with people. I am coming across many people who even with a well installed system and it is setup for optimum operation it is still costing them double what the previous old outdated gas boiler (non condensing) cost them. These people are literally ripping out the heat pumps and going back to gas, this is giving the industry a bad name because the initial outlay and upfront cost for the heat pump system is more than a domestic gas boiler costs. 

So the industry is getting a well-deserved bad name as the sales persons are not doing a properly costed comparison of the two alternatives when quoting for the work.

richardc1983

Rodders53 said:

richardc1983 said:  I work in the HVAC industry but I believe in being honest with people. I am coming across many people who even with a well installed system and it is setup for optimum operation it is still costing them double what the previous old outdated gas boiler (non condensing) cost them. These people are literally ripping out the heat pumps and going back to gas, this is giving the industry a bad name because the initial outlay and upfront cost for the heat pump system is more than a domestic gas boiler costs. 

So the industry is getting a well-deserved bad name as the sales persons are not doing a properly costed comparison of the two alternatives when quoting for the work.

Yep exactly that. I work in FM, not just HVAC but I have to be knowledgeable of all these things as we run client buildings and so we will deal with things on a commercial level.