Cost Saving of Wood Burner (kw/h gas consumption reduction v's cubic meters of wood burnt).

[diyFans]

I am considering the pro's and cons of getting a wood burner fitted to offset the cost of gas central heating (which I intend to keep).

The only option I have available to me is an inset wood burner, as opposed to a free standing one. The inset wood burner would be installed into the space vacated by our old gas simulation fireplace at the bottom of a chimney stack on a double brick outside wall.

Discussion thoughts 1./
If properly insulated, how economical would a modern inset wood burner be compared to a free standing one that is not inset of course?

Discussion thoughts 2./
Has anyone done a cost analysis over a year before and after the fitting of a wood burner? i.e. gas usage drop in kw/h, against the amount of wood burnt in cubic metre's. I ask the question in terms of quantity of fuel burnt rather than the cost of the fuel because the price of wood and and especially gas, are subject to fluctuation and could therefore skew results considerably. I realise any results are dependant on type of wood burnt(and how well seasoned), how efficient your burner is, whether it's an inset burner or not, and maybe whether it's set in/on an outside wall. However, it would be useful to a have a rule of thumb if anyone has ever analysed this for themselves. Fundamentally, I am trying to assess if I can save enough money to claw back the cost of fitting the wood burner over a number of years, and how many years that might take. I intend to use the wood burner enough to burn through 3 cubic meters of firewood per winter which I can buy for £340.

Discussion thoughts 3./
I realise hardwood takes longer than softwood to season. Presumably, hardwood burns for longer than softwood, and therefore in theory provides better economy on a cost/burn time basis. If this true, has anyone had experience with both types of wood and been able to draw any conclusion regarding the comparative number of hardwood /softwood logs burnt over a set period?

Thanks for reading,
Regards Pete.

 

[muggles]

There's lots of "it depends" on this, but as an example...

800kg of kiln dried birch logs cost £469 https://www.uklogsdirect.co.uk/kiln...-logs-c4/kiln-dried-birch-logs-large-crate-p5

Kiln dried birch will give you 4kwh/kg (ish). So that's 4 × 800 = 3200kwh

469 ÷ 3200 = 0.1465, or 14.65p per kwh

Gas under the current Energy Price Guarantee is about 10p/kwh, so burning wood will cost you more.

I can't really comment on your firewood for £340 as we didn't know what that 3m³ weighs, whether it's hardwood or softwood, or how well dried it is. Unseasoned hardwood will give as little as 1kwh/kg, hardwood stored for 2 years before burning should give around 3kwh/kg

 

[oldbutnotdead]

If you are paying for fuel for your woodburner it'll cost you more for the heat than mains gas at current prices. Oil and LPG the sums change.
Forget recovering installation costs- not going to happen.
3 cube lasting a winter? That'll be a very small woodburner, it'll give you one cosy room but a chilly house if the central heating is off.
Plus factor in time required for stoking and raking out, time required to stack your 3 cube of timber....
If you want one cos you like the Real Fire experience then fine but there's no money saving to be had.

 

[Fred Blogs]

If you are paying for fuel for your woodburner it'll cost you more for the heat than mains gas at current prices. Oil and LPG the sums change.
Forget recovering installation costs- not going to happen.
3 cube lasting a winter? That'll be a very small woodburner, it'll give you one cosy room but a chilly house if the central heating is off.
Plus factor in time required for stoking and raking out, time required to stack your 3 cube of timber....
If you want one cos you like the Real Fire experience then fine but there's no money saving to be had.

And they stink not to mention the dust and smoke discolourisation that can occur. I was quoted £4000 to have one installed and that was on top of buying the fire and the flue bits and pieces. I don't think the company wanted the job but I declined anyway. My son in law sells seasoned firewood so I had an unlimited, free, supply of wood which is why I looked at getting one. Having had a couple of narrowboats in my time which had wood burners in them I know all about the mess, the stink, and the work involved in keeping one going especially in the winter. So so glad I didn't follow up on my madness.

 

[Diyisfun]

I have a multifuel inset burner. It was in the property when we purchased.
I have a old v. cold house, especially the living room, burning wood does get the living room nice & cosy. This time of the year it is still used for a few hours in the eventing. The main heating is off.
I am quite fortunate in that I have a supply of free pallets that burn very well.
Just to add I am not on mains gas my heating is by LPG.
I would not say my house is warm at any time but my heating bill is high, with only 2 people in the property i try to heat the rooms we are using.

 

[Nintendofan]

I am quite fortunate in that I have a supply of free pallets that burn very well.

Not sure how many kilowatts of heat you get from one pallet plus the effort to cut it up but we sell our old pallets here for £2 each to a local pallet dealer.

 

[amfisted]

We had a multi fuel stove installed in our previous home in 2016, and used it for about five years. I've never done a cost benefit analysis, but I'm pretty sure it cost more to feed the stove with enough wood to keep us warm in winter than it would have done to run the gas central heating on a higher setting.

The stove looked wonderful when it was burning and gave off a tremendous amount of heat. However, there were a number of factors that eventually persuaded me that we'd be better off without one. First the cost of wood as above, and the variable quality of same when the relatively few reliable suppliers in our locality ran out of stock. Second, the sheer pain in the arras of moving wood deliveries to storage and then bringing the wood to the fire. Third the smoke pollution, which caused problems with our neighbours. We burned mainly kiln dried wood and it was a DEFRA approved stove, but that didn't stop the smoke from upsetting people. And fourth: the intense heat from a wood burning stove can cause condensation to form on the cold walls of unheated rooms, and it can also cause condensation in a poorly ventilated loft.

In short, I wouldn't bother. I'd let your central heating boiler do all the work instead.

 

[Mr Chibs]

Not scientific, but I've got wood bins, that are: one pallet high x long x 2/3 pallet wide. This winter I've gone through 1 and half bins of wood, had a fire every evening apart from 2 nights since middle of October.

I'm not too choosy on wood type, some have been willow, beech, birch and bits of fruit woods... It is seasoned though, minimum of 1 year, up to 3 years old. I don't pay for the wood, I keep an eye out and ask when I see it being felled, it usually costs me some lagers/beers to the tree surgeons.

I have loads and loads of bits of dry kindling to get it started, quickly and get it hot quick, this helps reduces the smoke.

I enjoy cleaving it and stacking, but that's because I'm a sad-o! Being honest, I like the intense heat and the look of it.

Can't say I've found an issue with condensation, but can see what amfisted is implying, turning heating off in rooms is not advisable, especially in solid brick properties, yes I know it costs my house heating is on, but low and in the lounge (where burner is) the heating is off when the burner kicks in.

If I was paying I've a feeling it might not be worth it, but that said, if it was £300/400 per year I would buy it.

 

[flameport]

I am considering the pro's and cons

It's all con.

The wood will be more expensive than gas
The woodburner will be a substantial sum to install and maintain
The woodburner will be significantly less efficient that your gas boiler
You will need somewhere to store the wood
You will need somewhere to dispose of the ash after cleaning it out.
It will deliver poor air quality for you and your neighbours

It's a pile of expensive inconvenience and problems.

 

[Diyisfun]

My pallet yard, needs to dispose of those he cant resell. I enjoy cutting them, there is a system I follow. In the past I would remove the nails, but thats hard work, so now just grab handfuls from the grate. The pallet yard is only a mile from home, so for me its winner winner, oh I have made a few bits & pieces ie bird box, bat box, work bench etc.