hi all,I was wondering if anyone has some ideas...
I am trying to calculate the potential savings of replacing my 12-year old D boiler (which still works perfectly) for a more efficient A-rated one. Based on the most recent annual consumption I arrive on a modest annual saving of only £68, or £1015 over 15 years. The calculation method which seems to be widely used assumes the unit gas rate to stay fixed, which is nonsense of course. It would be better if the calculation would use a variable to reflect any future rate changes.. Does anyone know how of a better method /know of a way to get historical figures that would help establishing trend /know of an organisation that does gas rate projections? Most grateful for any suggestions.
09-05-19, 00:21DutchCaerleonhelp needed forecasting gas rate changes for boiler replacement calculation
A tricky question indeed. The chart gives you a good indication of savings, however you also need to consider maintenance and service costs of old boiler, also the level of efficency is proberly, highly unlikely to be as high as quoted on your chart making savings higher. Install cost is a factor to consider, and have you considered going greener by switching to electric boiler heating system. Less maintenance cheaper install and more efficent but a little more expensive to run.
There are all sorts of things to consider when changing your boiler, but you can only compare on a like-for-like basis. which means ignoring all the other losses in the system and other optimisations that may be worthwhile as an alternative.
On the face of it the new boiler is only 9.5% more efficient than the existing one and you say it (the existing) is working perfectly.
How much would the total cost of the work be?
It's fairly clear from your figures that the "payback" time for your level of consumption is way too long to make it a worthwhile exercise.
Also the figures quoted are for the boiler only and don't take into account other losses. (which would be the same ££ but a greater percentage with a more efficient boiler)
From the figures given on the face of it I'd say it doesn't seem worthwhile. I can't see how conventional electric heating would cost you less (unless you have solar panels). The efficiency is much better (near 100% and no other losses) but the per kWh cost is at least 4 times as much as it is for gas.
Assuming your insulation is up to scratch - it has to be really good, have you looked at the idea of a ground source heat pump? There are government grants
A few points.
The old boiler efficiency is a maximum figure and is therefore not realistic. If you are lucky maybe 75%.
The new boiler efficiency rating is calculated differently and is conservative if the heating system is set up well.
Secondly your old boiler is other older than 12years or was, might I suggest, fitted illegally as non condensing boilers should not have been fixed after 2005.
Thirdly the suggested new boiler is not a direct replacement. The first is a combi and the new one is open vent heating only which means installing a cylinder and extra gubbins, unless I am missing something.
Your old boiler was a good un. Stick with it a bit longer. It will all be old tech in a few years(fossil fuel). The cost of heat pumps and other technology will hopefully come down.
I have the same boiler as you, it's just over 20 years old and still works perfectly ( touch wood ). At the last service I asked about replacing it, and was told these models go on forever, and a new one would never pay for itself ( unless you can get a grant). Stick with what you have got, I am going to
I agree with Duppy (which is what I was trying to say in my first post)
You didn't say whether you were going to go from combi to indirect but that would be a MAJOR amount of work (disclaimer: I now have a combi it was a big mistake and I would go back to indirect in a heartbeat if £££ allowed)
The quoted savings from not storing heated water are a nonsense unless all of your pipe runs are really short.
As far as trying to predict based on future gas prices, you can't, and if you think you can then you're in the wrong job, you should be trading on the long futures market.
HERE is why 2009-2019
look HERE too
I would never go combi and if I end up buying a place with one, will probably go indirect - you get opportunity for immersion backup and heating from surplus solar as well as lower blood pressure. That last point outweighs any cost. You can't put a price on quality of life if you loathe your boiler!
11-05-19, 10:14Strutt G
I moved from indirect to a combi back in 2011 and have saved money on energy costs.
But the previous Potterton boiler was approx 30 years old and in situ when we moved in, so guess the combi was bound to be more efficient as not comparing new for new.
The fact is there will be no cost saving overall because the combi will not have the same shelf life.
The servicing package rises each year, so I called and said I had a better deal and the fee was reduced.
Just another example of not letting contracts roll on....
Completely agree, I stupidly listened to the so-called experts, I should have trusted my intuition.
Yes, no backup if the boiler stops working, longer runs of cold water waiting for hot, then the water in the pipes cools down. It's awful.
Modern cylinders are very well insulated, heat loss is minimal. The heat loss from the long runs of cooling pipes far exceeds anything the cylinder would lose.
Don't start me off about plumbers...arghhh...they talked me out of my original plan. and now I realise it was because they didn't have the tech know-how to work out how to control it. I stupidly agreed to resite the boiler and go combi. I regret it every day and if I win the lottery sod the consequences I'm ripping it out and starting again.
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And I also agree with you that switching to conventional all-electric currently doesn’t make a lot of sense financially - and my hunch is that unit rate for electricity will go up as demand for electricity will go up due to increased demand e.g. the electrification of uk car fleet plus Hinkley Point C with its minimum guaranteed price will undoubtedly affect consumer prices.
From the little info I know a ground source heat heat pumps require a large garden (700m2) or, for a vertical installation, reasonable easy access to the garden for a drilling rig. I have neither... and like so many property owners, our 1906-built property is not well insulated, and insulation itself is a bit of a headache in rainy S Wales (level 4 on the British rain index) where cavity wall insulation is not recommended...
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I agree that we’re in a transition period with new technology to replace gas-fired boilers still maturing; cost will come down, and in the meantime I’m reducing energy consumption with smart switches for electric devices to reduce needless power usage and smart TRV with timers and Tado smart radiator thermostats to only heat where needed and based on occupancy...
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I’m open minded about combi/indirect solutions. I made a mistake in selection the new boiler; was looking to see how one of the best-performing new boilers with a high % efficiency would affect the period over which the hardware cost could be a earned back, based on a similar 28-30kw output as I currently have, but as it turned out I picked not a combi model. I am interested in modelling indirect heater with a solar heater at some point in the future.
I guess the purpose of the post was to see if anyone knew of a formula that would consider gas price changes for consumers, but it seems that there are no scenarios available that would help incorporate future price movements, perhaps based on past movements of consumer prices. It would for instance be interesting to see what the major energy providers charged consumer for gas over the past 20 years and see how they changed. If there was a long term trend, one could incorporate that into the modelling.
I read somewhere that UK gas prices are set to increase 5-10% over the next 5 years, but it wasn’t clear whether that would be consumer/wholesale etc.
I know you addressed the insulation point I made but without a doubt from both a financial and green viewpoint improving the insulation will give you the best returns long term.
The government want to discourage fossil fuels, so looking to the future if there's any comparison/analog between discouraging smoking/driving IC vehicles/heating with fossil fuels (choose your poison) I can only see gas prices rising by market forces plus some discouraging taxation (perhaps until z'ere are ze riots).
The problem for almost everyone is that capital investment is limited or we would all have electric cars and triple glazing.
I applaud your forward looking method to try to work out whether it's worthwhile; price rises long term are inevitable but second guessing government policy and geo-political influences...
You can only model on a guess...my guess is that gas prices will double in the next 10 years, what's yours?
I guess we have to wait until UK gov politics returns to a semblance of normality and hopefully relaunches a bolder household energy efficiency programme or come up with something much more ambitious.
If smoking/air quality showed anything, it’s that politicians do anything to avoid forcing the electorale to change behaviour/make lifestyle choices or change cars/discourage car usage. And a typical window to deliver policy/behaviour change is 15-20 years.
I assume gas prices could stay relatively stable and not rise more than 10-15% until 2023, but I guess much depends on stability in domestic (North Sea) gas production/supply from Norway/Netherlands, £-€ exchange rate and inflation.