Central Heating Payback Period

[stuartpaul]

Long post, please bear with me.

Survey permitting (there in lies another story!) we’re about to move to a 3 bed detached bungalow with night storage heating. When I posted on here a while back such heating was reasonably well bashed on grounds of running cost. I generally agree with that view.

However, I’m starting to look at the costing versus payback and whilst on the face of it gas fired is cheaper to run the installation costs appear to take a considerable period to be realised and I’m starting to wonder if in the longer term it will be worth it?

In an attempt to put some raw numbers on it I’ve used the current energy use for our 3 bed semi. Annual consumption 3,972 kwh electricity (cooking lighting and workshop!). 9,497 kwh gas for heating and hot water. We also run a log burner which can negate the heating.

At current tariffs this equates to about £980 over the last year.

So, going all electric I’ve made the assumption that we’ll still use the same overall numbers of kwh’s (13,469) by basically saying the current gas usage will be transferred to electric usage, - crude I know but I don’t have any other figures to use.

Using one of the cheaper economy 7 tariffs this runs out at £1,224. I’ve allowed for 75% night rate and 25% at the (crippling!) day rate.

So a difference of £244 per year.

A new GFCH system with combi boiler (including new gas supply to the property) is going to be in the region of £6,000. So my simple maths leads me to a conclusion that it would take over 24 years for the GFCH to achieve payback.

However, if we stick with storage heaters I’d go for a more efficient models plus some other tweaks (new shower etc) that I reckon would work out at about £3,000 so this means the payback only has to deal with the remaining £3,000, so that would be 12 years.

This does seem to be a longer period and to me at least appears to be rather uneconomical. Also need to add things like boiler servicing which can further extend that period.

I know there are other factors to consider if moving to gas (less worry about fuel costs, convenience, efficiency of boiler etc) but does the above make sense?

What am I missing? What would others consider a reasonable payback period?

 

[AJB Temple]

Honestly this is not a financial payback question. It is all about how many years you can stand to be cold for. Night storage heaters are hopeless at delivering heat when you really need it. I had them in a flat we refurbed in London and sold on: half of one winter was enough to convince me that they are next to useless when you get home from work and expect a warm house. Prepare for a winter of cold evenings. You can watch the electricity meter whizz round as you shiver.

 

[Woody2Shoes]

I think that the investment with the fastest payback - by a fairly long margin - is likely to be insulation plus draughtproofing - if your new house is anything like the "average" UK housing stock built before about 2007. The results of this may then govern your thinking about the urgency/value of other changes. Cheers, W2S

PS Has your new house got an "energy rating" and when was it built?

 

[HappyHacker]

I am with Woody: insulation and draft proofing as a first priority with insulation internally if necessary. Try to cut down on cold bridging as much as possible, then storage heaters may work well. Have a look at Quantum heaters which claim to give more control over the dissipation of the heat so that you are not meant to get cold evenings.

 

[Wuffles]

Air source heat pumps?

No idea if the Govt have cancelled the Renewable Heat Incentive (RHI) yet, but they'll pay for themselves fairly quickly.

5 bed house, 24/7 365 at 20 degrees C costs us around £1600 per annum, less money for solar panels, less Govt subsidy. We only have electric, so the £1600 includes our high electricity usage too.

Look into it anyway.

 

[sunnybob]

Insulation if at all possible, especially cavity wall with rockwool. I had a 3 bed semi 60's built and had the thing so well wrapped that all the heating was a gas fire downstairs, and single jet gas hall heater on the upstairs landing.

But even with all that, Gas central heating is the most convenient cost effective way of warming your house and supplying hot water on demand.

Have you shopped around for the central heating? The boiler and rads shouldnt be more than a couple thousand unless the house is big. Do all the rad and boiler hanging yourself, you can run all the pipework, and just pay someone to connect and commission.
I've just bitten the bullet here and had CH installed (you might not think it, but Cyprus does have a winter), and after 6 winters of huddling under a duvet watching tv in the evenings, it was magic to not have to even think about being warm.

 

[beech1948]

Electric storage heating is probably there because there is no gas supply. You would need to add the installation of a gas pipe.....God knows what that would cost......maybe. £3000. Just a wild guess

 

[Phil Pascoe]

I suspect it's LPG.

 

[Wuffles]

I suspect it's LPG.

Calor will fit LPG tank and gubbins for free if you sign up to their HORRIFIC tariff for a year or two I think. Well, they were offering that last year at least.

Seriously though, look at Air source heat pumps, only need electric and some oversized rads, and given you are starting from scratch, why not go all in.

 

[RogerS]

How long are you going to be living there and when you do move what would your potential purchasers prefer?

I'd try the existing storage heaters for a year on the best Economy 7 rate you can find and then see if they work for you. If they do then think about more modern ones.

 

[Terry - Somerset]

Some good advice from others. However your assumption of 75% night use of electricity seems too heavily weighted to the hours of darkness - if reworked with 30% or 50% night time demand, and possibly the risk of increases to energy costs, you may find the payback period much more palatable.

A purely personal view - if it is affordable and you are planning to live there permanently, rather than a 2-3 year period climbing the property ladder, you will continually regret not installing a cheaper to run, more effective alternative. If you do sell it will improve saleability and price.

I made a similar (but not as important) "mistake" when we moved into our current house. I considered PV panels but the payback (with govt subsidies) was 8-10 years. Each time I looked at it (every 2/3 years) the subsidies had fallen and so had the cost of installation - payback remained much the same. After 12 years I regret not having done it at the outset.

Terry

 

[Phil Pascoe]

i moved 16 months ago and looked into it quite carefully as we only have electric. Neither ground source, air source, solar thermal or solar photo voltaic made sense economically. My friend had large photo voltaic system put in for £16,000 when the feed in tariff was about 42p per unit and he's now coining it (on us), but since then it hasn't been anything like so lucrative. I can see home made solar thermal making sense, but that's about it.

 

[stuartpaul]

Thanks for all the useful thoughts.

I should have included this in the OP but this is (hopefully) our last move. Current plans are from there to a box!

Bungalow was built in 1995 (ish) and the EPC is 53 (E) with potential to move to 81 (B) but given this includes such ludicrous measures as digging up and insulating under solid floors (really?!) we won't be going that far. It does comment on changing to high heat retention heaters though. This would save quite a lot as the ones fitted are the original 'monsters'.

Gas is available within 25 metres and I've hopefully factored this in to the original cost for GFCH (a neighbour paid about £600 six months ago). LPG and oil discounted due to cost (installation) and room for storage.

Research shows that modern storage heaters (Quantum being the best) are much more efficient (in terms of heat delivery through a day) than they used to be, - cold by early afternoon.

I've looked briefly at air source (no room for ground source) but simply don't have the upfront investment, - it's quite a lot more than bog standard GFCH. Still, - I think I'll get a proper quote as you never know!

Walls have cavity insulation but the roof requires another 200 mm at least. I will be insulating/draft proofing the hell out of the place!

I think we're both erring on the side of GFCH because that's what we've lived with for the last 30 years and it's instant (ish), convenient, controllable and of course cheap to run (if you discount installation!).

 

[Wuffles]

I've looked briefly at air source (no room for ground source) but simply don't have the upfront investment, - it's quite a lot more than bog standard GFCH. Still, - I think I'll get a proper quote as you never know!

That is very true. Out investment was close to £9k for two heat pumps and new rads. Luckily it was all fitted by me and a mate and then signed off by the supplier of the pumps. Quotes were £17k. Do look into the RHI though, as that literally pays for what you buy if you're canny.

I think we're both erring on the side of GFCH because that's what we've lived with for the last 30 years and it's instant (ish), convenient, controllable and of course cheap to run (if you discount installation!).

Yes, I would probably have been the same, we just had no option of gas. Nothing wrong with that.

 

[nev]

We started with aged night storage heaters, then found we need another heat source in the evenings as they'd effectively run out by then. They're also useless in the summer because you don't want any heat in the daytime, maybe a little in the evening which you can't do.
We added a multi fuel burner which sorted the evenings out, but still had a big electric bill. Removed the NSH and had the burner run the heating, so now its cold in the mornings! add electric panel heaters for the morning. Now still a biggish electric bill and have to wait an hour or so for the heating to kick in after lighting the fire. Using a (£6) bag of coal a day if keeping the fire in overnight.
Fed up of the hassle of making the fire every day we bit the bullet and bought a Main gas combo boiler (£600), converted to LPG with loose 47kg bottles and haven't looked back. Annual Gas consumption equates to about a bottle a month @ £50 - 60 a bottle. Its on when we need it, clean and cost the same to feed as the burner, and is pay as you go softening the blow of a big bill.
(2-3 bed semi, cavity walls)

 

[Phil Pascoe]

You must have a special Welsh discount on coal if you're getting it for £6 a bag. Our is £8.

 

[Phil Pascoe]

On our EPC they told us we should insulate under the floors, and gave a totally ridiculous estimate of cost and payback time. They also told us we could change the rating from a D to a C by changing the lamps in two fittings ... all the while neglecting to tell us that there was 24 feet of single skin four inch block wall between the bungalow and the garage. No wonder few people take any notice of EPCs.

 

[Woody2Shoes]

On our EPC they told us we should insulate under the floors, and gave a totally ridiculous estimate of cost and payback time. They also told us we could change the rating from a D to a C by changing the lamps in two fittings ... all the while neglecting to tell us that there was 24 feet of single skin four inch block wall between the bungalow and the garage. No wonder few people take any notice of EPCs.

EPC = done by the tea boy, usually! :lol:

It's still the case that most houses have a lot of scope to improve their energy efficiency - and not necessarily that expensively either. The savings start on day one and carry on for the foreseeable future.

Cheers, W2S

 

[nev]

You must have a special Welsh discount on coal if you're getting it for £6 a bag. Our is £8.

that was a few years ago, its gone up now 6.50 for house coal 7.00 for anthracite.