Wood Pellet Running Costs

[geoff1306]

Hi,

I am looking to sort out new heating system to replace an old oil boiler - house is not insulated enough for heat source, so I am thinking of biomass pellet boiler. But all im getting is bulls**t from idiots on the running costs - does anyone have any real experience and/or calcs that are based on fact?

 

[Doing it for the kids]

Spend your money on insulation. Then look at GSHP perhaps

pellets are the most Expensive of them all I think

 

[geoff1306]

Spend your money on insulation. Then look at GSHP perhaps

pellets are the most Expensive of them all I think

pellets are the most Expensive of them all I think .... that was my conclusion as well.... cheaper to have oil or gas... only thing that works out ok is logs... but its the hassle of feeding a log burner

 

[Horn&corn]

Few boilers second hand with Rhi for sale. Depends on how much risk you want. Cold wife and family not much fun!

 

[chickens and wheat]

Pellets are pricey, but time spent feeding the boiler is next to zero.
In 8 years ive had one auger tube wear thru and one auger pipe set like concrete after a leaky valve dripped slowly but steadily right into a joint. Boiler was off so water seeped into pellets. Thats 5 pellet boilers.

Heard many stories of chips blocking systems, burning out motors or worse .

Soon be time to replace all auger tubes.they wont last 20 years. The worn place was on an auger weld so will replace that lenght with fresh. Its only 10ft long, dont know why it ever got welded

 

[ste]

Just about to get our last RHI payment next month so been in 7 years. Ours is a Okofen 25kw, heating a large 4 bed stone farmhouse with loft insulation and double glazed windows. Can honestly say we don't regret it one bit.

We priced up oil and pellets and found that the install cost was higher for pellets, but this was more than offset by the RHI grant (what we got has paid for the system in full, servicing and the vast majority of the fuel for the last 7 years, as we got in just before they dropped the rates). We went for a manual fed at the time as we couldn't get decent prices for bulk delivery so couldn't justify the extra for the storage and transfer system. Although when we installed it we built the shed around it so this could be done later if we wished, but also doubles up as pallet storage so we can buy out of season and store, and can handle with the skid steer in there. Same with the ash, only need emptying once a month in winter.

Servicing cost around £250-300/year. Breakdown wise, we've been lucky, only had a issue with a sensor that the mechanic told me how to fix over the phone and the occasional tripping out with a plug in the feed auger but restarting usually fixes that.

As for pellet use, its around 7 tons a year with the heating on 6am-9am and 3pm-9pm in the week and 6am-9pm at the weekend, plus a water heat at 6am and 5pm. Comparing it to a relative that's on oil with heating on less and a slightly better insulated and positioned house, I'm happy with that cost as I think our oil usage would be a similar cost to pellets. Have been using 15kg bags but are on our last 3 pallets as are switching to 1t bulk dumpy bags. Filling isn't bad, in summer its usually once a week and 3 times a week in the winter. The reason for the switch is 450 empty 15kg plastic bags take some getting rid of. It will blow our summer savings as they don't discount the bulk bags in the summer the same as the little ones, but the ease of use and disposal is much better plus we seemed to have less ash with the bulk ones.

Would I do it again with out the grant?? If asked at the time then no, but now after using the system I would probably go with it. What I would say is watch the cheaper end of the market, from what I see cheaper definitely isn't a good thing with this technology. And do your research into the supplier and manufacturer, we landed with a decent firm on both counts and have no regrets

 

[Wisconsonian]

The best comparison you'll get is your current heating system. Assuming you have a few years of records, and you keep the same temperature, you should be able to estimate the heat required, and convert that into the cost for the season with different alternatives.

Air sealing is the first place to save money. In our houses, that means sealing up the air leaks into the attic, before even thinking about insulation, replacement windows, basement air sealing, etc.

 

[rollestonpark]

Personally... I think pellet boilers are far too expensive to run and I very much debate their environmental benefits. The huge cost in £ and energy to produce pellets (and often transport them from the US) makes absolutely no sense to me. Might as well have a kero boiler... That's just my view, some may well say I talk rubbish etc... but there you are.

But a chip boiler running on waste wood from a local source at £35/Ton @10% moisture. That's where it's a goer. But it won't suit everyone's situation. Best in a farm setting for obvious reasons.
Yeah you'll have stoppages with this type of fuel, it all depends whether that bothers you. For me, run on cheap fuel accept the stoppages and enjoy a warm house.

Chris
living in an old drafty farmhouse.

 

[geoff1306]

Many thanks for all the replies - I am building a proper spreadsheet for this problem.. and will try and get it built into a webpage to make everyone's life easy. But Im coming to the conclusion based on science that wood pellets are not economical - im ignoring whats green as thats another whole debate.

Below is my initial start

Fuel Type	Boiler Cost (25kw)	Install	RHI	Fuel Cost	KWh/kg or litre	Cost per Kw
Oil	1800			£0.56	10.35	£0.05
Wood Pellets	12000			£0.46	4.9	£0.09
Off Grid Gas (flogas)	1000			£0.43	7.08	£0.06
ASHP
GSHP
Solar+Battery+Elec

All comments and inputs welcome - happy to add in woodchip and log boilers

 

[stuart o]

I dont think any one can argue, even with a good make pellet boiler (windhager) that dose not require many repairs (£300/8 years) or expensive service (£275/year) and the cost of pellets, (£600/t jan 2023 using ave 5t/year through a 15kw boiler heating and DHW for a 200m2 house occupied 24/7, although we do have a 5kw wood stove in the living room) it is far more expensive than oil currently, even at the highest oil price, it was only slightly cheaper. its also a fair point that some older homes are not best suited to GSHP,
I made the move solely based on the RHI payment which covered the install costs, as i only had 3 open fires with a back boiler (comparision heating oil cost 70p/ltr)

so what will be the options in the uk after 2024?

I'm currently looking into none accredited hardwood pellets which have a higher calorific value for what appears the same cost, does anyone out there have any experience of hardwood pellets?

 

[Wisconsonian]

600/ton pellets and 70p/liter oil will not last. Hardwood pellets are marketed as premium here, no difference really, or slightly higher BTU for softwood.

 

[Old apprentice]

Any one tried straw pellets in a wood pellet burner?

 

[555]

Straw pellets will eat your boiler after a year! Straw is very corrosive when combusted. Unless the boiler is designed for straw.

 

[Funny Farmer]

Many thanks for all the replies - I am building a proper spreadsheet for this problem.. and will try and get it built into a webpage to make everyone's life easy. But Im coming to the conclusion based on science that wood pellets are not economical - im ignoring whats green as thats another whole debate.

Below is my initial start

Fuel Type	Boiler Cost (25kw)	Install	RHI	Fuel Cost	KWh/kg or litre	Cost per Kw
Oil	1800			£0.56	10.35	£0.05
Wood Pellets	12000			£0.46	4.9	£0.09
Off Grid Gas (flogas)	1000			£0.43	7.08	£0.06
ASHP
GSHP
Solar+Battery+Elec

All comments and inputs welcome - happy to add in woodchip and log boilers

Without RHI stick to oil for now, and see what happens in the future, they might restart the RHI.