Biomass Boilers

Pistol1

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Well, my gas combi boiler is very much on its way out. Time to bite the bullet and replace it before winter sets in...


However, the plumber I have used before has got a real thing for biomass boilers. He reckons he's installing one every week, soon to be two a week. Seems you can get a 10-year interest-free finance scheme to pay for the installation, and a subsidy from the government towards the fuel costs - supposedly leaving some people £600 a year in profit!


Anyone got one of these heating systems that could offer any advice as to how good they are?
 
I've been doing research as we're in the same situation with two old and inefficient gas boilers.
What is relevant is the renewable heat intensive (RHI) payment which becomes available for domestic installations April 1st 2014.
In a nutshell, with an investment of between £20,000 and £30,000 for the system installed, over the 7 years of RHI for a biomass boiler for a slightly larger house, with a loan paying around 5% interest, we stand to make over £10,000 (probably nearer £20,000) profit.

The biomass boiler will heat a large thermal store which will provide all the heating and hot water we need.

Disadvantages
  • Requires a very large shed sized building (close enough to the drive to deliver the wood pellets) to house the boiler and pellet store.
  • Requires a thermal store (in our case, larger than the two old boilers being replaced)
  • Requires cleaning out of the ash every few weeks.
  • Requires regular deliveries of wood pellets.
  • Requires a large investment (via a loan in our case).
  • New scheme with some uncertainty.

Advantages (in general)
  • You get your money back on the purchase of the boiler and make a profit.
  • The cost of wood pellets is likely to inflate less than natural gas, so you will probably save more money in the long run (they currently cost about the same)
  • Potentially raising the value of your home.
  • Lowering your carbon emissions significantly.
..and specifically for us...
  • Instant, mains pressure hot water (we currently have to wait two minutes for upstairs showers to heat up).
  • Potential to supplement the saving on heating the hot water by adding an immersion heater to the thermal store which is powered by solar panels.
  • Removal of the hot water tank behind the false wall of the boy's bedroom.
  • Removal of the cold water storage tanks in the loft.

We're probably going to get a biomass boiler and solar panels fitter March or April next year.

Ask your plumber if you can go visit some of the people he has installed a biomass boiler for.
That's the next step for us.
 
Cheers for that information Stuart, very helpful! If we got one, it would be sited outside, just outside the utility room window; pellets would have to be stored in a shed down the garden. I hadn't really calculated how many pellets such an appliance would get through, hopefully a small shed would be enough storage space as we just put one up!

I think the biggest problem would be siting the hot water tank ("thermal store" I presume); unless we just stuck it on the floor in the utility room, which would get in the way and look awful, the only space available for it is a 600mm wide appliance cavity under the worktop, which was earmarked for a tumble dryer we never got round to fitting.

I was just mildly interested at first, til I realised that the 0% finance repayments would more than likely be less than our current gas bills!
 
The only option I have been presented with is an auto feeder for pellets, which is why the store has to be right next to the boiler.
Otherwise, you're going to have to feed them in yourself, aren't you? Like every day? I don't know because it was never presented as an option.
If I recall right, we'd need a storage space large enough to cater for 4 tons worth.
The thermal store we've been discussing is several hundred litres. Larger than a typical large hot water tank.

The persuasive argument for getting a boimass boiler is that the alternative is spending money on a gas boiler which you will never get back. Whereas the money you spend on a biomass boiler, you will get back. And more.
Unless you are passionate about the environment, in which case, that may be more persuasive.
 
Yeah, I don't think we'd have the space for an auto-feeder and hopper, or 4 tons of pellets! Have got the rep coming over tomorrow to discuss what kind of system would be required, should be interesting :)
 
Let us know what he says. Would be interested in the kW output they recommend.
 
Well, the guy came round and we had a good chat. Very confusing though!


He specced a 28kW Trianco Greenflame external boiler. He thought we would probably use 5 tons of pellets a year, at an estimated cost of £1,000. That's for a (currently) 3 bedroomed semi detached house.


The installation cost would be £16,800. They offer a finance deal (no way could we go for this if they didn't, to be fair!), with interest working a lot like credit card interest: if you paid it back over the 10 years, you'd end up paying about £14k interest!! So what he recommended doing, was taking your quarterly RHI payments, and using those to pay the finance off within 3 years. Then, you get the remaining 4 years of RHI payments in your back pocket.

Based on his working out, we'd be looking at about £1,400 a quarter in RHI payments. £260 a month finance payments (we're currently paying £290 a month to British Gas, and most of that is for gas!), plus about £1000 a year for pellets.

We're currently oscillating between being really keen to do it, and being cagey about whether it's all too good to be true; if the numbers all work out as we've been led to believe, it's like magic money, getting paid to heat your house! Surely there's a catch..?

We've got 3 kids and a house that eats money, if we screw this up and end up with a millstone round our necks we're done for. But if it's all above board, it would be amazing. Think we need to get the bloke back round and go through it all again to make sure!
 
A friend installed a biomass boiler last December coupled with a solar thermal system. He lives just North of Inverness and was spending ~£2500 per year on oil for heating and hot water. The system cost ~£20K, takes up half his double garage, and he uses logs as fuel. He is on target for fuel costs of ~£450/yr. He didn't need to fuel the boiler June, July or August (thermal solar took care of water needs). He buys in a lorry load of wood at a time (the forest type lorry) , and has a huge store to dry the logs. His wood requirements for his house works out ~10ish tons/yr.

Finance partly came from the Energy Saving Trust which provided a £10K interest free loan, payable over 10yrs (I think), which is linked to his reduction in bills.

As for having automatic feeders, if you are lazy and money isn't a problem go for them. In the middle of winter he has to fill the boiler with a barrow load each day which takes minutes. Remember even if he misses a day the thermal store has several days worth of water to heat the house.

Although government payments would be a bonus the system keeps getting knocked into the long grass. In short the systems do work, cost a shed load but reduce your bills significantly but payback is long term, but don't expect any money from the government any time soon.

By the way up near us is a wood pellet factory. Their contract only allows them to send the pellets over to N.Ireland or it could be Ireland to be bagged. Then they get sent back over here to sell, which makes a mockery of carbon saving.
 
Got the bloke coming back tonight to go over the numbers again. The main thing which is troubling my mind over the whole scheme at the moment is that the RHI scheme is untested as yet (for domestic installations, at any rate). The rep has is effectively promising us a certain payback, but the scheme doesn't start til April next year, and you wouldn't see any money until the first three months after that. If it didn't pan out exactly as he's maintaining, we'd be left screwed.
 
The guy cannot guarantee any money from the Government as the date the scheme kicks in keeps getting moved back. If you are buying the system for the money you'll make and he is selling it on this then I would look elsewhere. These systems should be all about the reduced energy bills not how much the Government is going to pay you.
 
Thought the RHI date was set for April 2014?


It primarily is about reduced bills - we're currently paying £1.8k per year for gas, and it's not going to get any cheaper. We need a new boiler anyway - so we either buy another gas boiler, which will be at least 10% more efficient but probably not much more of a saving than that, for £1.8k; or, we go the biomass boiler route, which should equate to a 50% reduction in fuel costs, with no upfront cost (with the RHI payments paying off the finance at an accelerated rate).


Plus it's more eco friendly and all that.
 
Again. Cheaper to instal and receives the RHI in April. Ground source heating. For the price of the biomass yoi could also install solar panels and a wind turbine and get FIT now!!
 
Guys, I know this is a fairly old thread, but there's something else you should consider (this comes from commercial clients who installed a biomass boiler in their new building as part of their 10% renewables Merton rule commitment).

Remember, the heat isn't controllable like it is with a gas boiler. A gas boiler burner would modulate up and down according to demand, a biomass boiler, when lit, will carry on burning until all the wood pellets are used up. So if you have 2 hours worth of burn from a certain amount of wood pellets, and your thermal store, hot water or whatever is up to temperature within 90 minutes, then you will have 30 minutes of burn that is effectively wasted, reducing the efficiency of the system.

Probably not a show stopper, but something to be aware of.
 
@Markee I was told otherwise at the grand designs shows yesterday. One of the manufacturers said that when the call for heat is lessening the system starts to automatically burn less pellet and eventually cuts off shortly after the call to say not more heat is required. He said it works almost identical to a gas boiler and you would get very minimal wastage at worst.

Not sure if he was talking bs but I will be looking into it as I hate the though of having an energy efficient source which wastes energy!
 
Based on what I have seen on these and its the same principle on my pellet fed bbq/smoker doesn't a thermostat control the speed of the auger screw that feeds the pellets from the hopper to the combustion pot so when its up to temperature it only feeds in what's required to keep it at that temperature?
 
The issue with biomass boilers Is that there is not set standard for pellet/fuel feed so you have to check the particular feature set of the boiler to determine exactly how it operates. Any good boiler would adapt the fuel feed based on demand, but it is not as quick to respond as a modulating gas burner. For those of us that have had commercial solid fuel boiler (coal) experience we know all about the issues of using a solid fuel source, auger/screw fed burners etc. They always require more care and attention to keep them working effectively.
 
All the wood pellet products that I have come across have computerised thermostats which control the speed of the feed from the hopper to the combustion pot just as rding says above - they then go into "tickover" mode to keep the water or whatever at the optimum temperature. Indeed, my home pellet fire does this with the air temperature of the room - when it does this the phrase "modulating" comes up on the remote control display.
 
Coming rather late to this thread (just signed up in fact), but as I have had a pellet boiler since Jan. 2013 my experiences might be helpful.

I have a Extraflame LP20 (nominal 20kW) boiler. This has an internal 70kg pellet compartment which is enough for 3 days in the depth of winter. We buy bagged pellets delivered on a 1 tonne pallet which lasts about 6 weeks during winter, at a cost of around £250 delivered. We get through about 4 tonnes a year for our 4 bedroom well insulated 1950s detached house.

First and most important point is, choose your installer wisely. Get recommendations and if at all possible use someone local. I did neither and am paying the price. I'm in NE England and the installer is in Merseyside, their service and support has been completely atrocious. The boiler has broken down twice now, first time was at the end of Sept. 2013, it took them 5 weeks to fix it (under warranty) and we had no heating for the whole of October. It broke down again the week before last and I still don't even have a date for a repair. The manufacturers (Extraflame) do not respond to my requests for help either.

Fortunately, I've found 2 companies who are working together to help me (massive cudos to The Centre for Green Energy in Hexham, and Piping Hot Stoves in Daventry for going way beyond the call of duty).

When it works (!) though it works extremely well. I replaced a gas combi and had a 250L pressuried hot water cylinder installed in the loft. The boiler feeds the radiators direct (no buffer tank needed) and is controlled by a programmable room thermostat. It takes longer to start up and produce heat than does a gas or oil boiler (10-15 mins) but otherwise behaves much like a conventional boiler.

Despite the problems I've had (entirely the fault of the installers) I do not regret switching to biomass. If this current boiler proves to be unsupportable going forward, I will replace it with a different make from my local installer.
 
Coming rather late to this thread (just signed up in fact), but as I have had a pellet boiler since Jan. 2013 my experiences might be helpful.

I have a Extraflame LP20 (nominal 20kW) boiler. This has an internal 70kg pellet compartment which is enough for 3 days in the depth of winter. We buy bagged pellets delivered on a 1 tonne pallet which lasts about 6 weeks during winter, at a cost of around £250 delivered. We get through about 4 tonnes a year for our 4 bedroom well insulated 1950s detached house.

First and most important point is, choose your installer wisely. Get recommendations and if at all possible use someone local. I did neither and am paying the price. I'm in NE England and the installer is in Merseyside, their service and support has been completely atrocious. The boiler has broken down twice now, first time was at the end of Sept. 2013, it took them 5 weeks to fix it (under warranty) and we had no heating for the whole of October. It broke down again the week before last and I still don't even have a date for a repair. The manufacturers (Extraflame) do not respond to my requests for help either.

Fortunately, I've found 2 companies who are working together to help me (massive cudos to The Centre for Green Energy in Hexham, and Piping Hot Stoves in Daventry for going way beyond the call of duty).

When it works (!) though it works extremely well. I replaced a gas combi and had a 250L pressuried hot water cylinder installed in the loft. The boiler feeds the radiators direct (no buffer tank needed) and is controlled by a programmable room thermostat. It takes longer to start up and produce heat than does a gas or oil boiler (10-15 mins) but otherwise behaves much like a conventional boiler.

Despite the problems I've had (entirely the fault of the installers) I do not regret switching to biomass. If this current boiler proves to be unsupportable going forward, I will replace it with a different make from my local installer.
Bunch of arses. Glad it looks like you are getting somewhere though. How much do you get back in rhi for that size?
 
Bunch of arses. Glad it looks like you are getting somewhere though. How much do you get back in rhi for that size?

Still in the process of organising the "Green Deal" assesment that's required before making the RHI application. I'll post here when it's all done and I have some numbers to report.
 
Coming rather late to this thread (just signed up in fact), but as I have had a pellet boiler since Jan. 2013 my experiences might be helpful.

I have a Extraflame LP20 (nominal 20kW) boiler. This has an internal 70kg pellet compartment which is enough for 3 days in the depth of winter. We buy bagged pellets delivered on a 1 tonne pallet which lasts about 6 weeks during winter, at a cost of around £250 delivered. We get through about 4 tonnes a year for our 4 bedroom well insulated 1950s detached house.

First and most important point is, choose your installer wisely. Get recommendations and if at all possible use someone local. I did neither and am paying the price. I'm in NE England and the installer is in Merseyside, their service and support has been completely atrocious. The boiler has broken down twice now, first time was at the end of Sept. 2013, it took them 5 weeks to fix it (under warranty) and we had no heating for the whole of October. It broke down again the week before last and I still don't even have a date for a repair. The manufacturers (Extraflame) do not respond to my requests for help either.

Fortunately, I've found 2 companies who are working together to help me (massive cudos to The Centre for Green Energy in Hexham, and Piping Hot Stoves in Daventry for going way beyond the call of duty).

When it works (!) though it works extremely well. I replaced a gas combi and had a 250L pressuried hot water cylinder installed in the loft. The boiler feeds the radiators direct (no buffer tank needed) and is controlled by a programmable room thermostat. It takes longer to start up and produce heat than does a gas or oil boiler (10-15 mins) but otherwise behaves much like a conventional boiler.

Despite the problems I've had (entirely the fault of the installers) I do not regret switching to biomass. If this current boiler proves to be unsupportable going forward, I will replace it with a different make from my local installer.

Can I be nosey and ask how much it was costing in gas to heat your house? We're presently on oil and looking to replace to either biomass or gas.

Thanks
 
I didn't keep *exact* figures, given that gas prices were consistently rising, but it was definitely very close to what I subsequently paid for pellets. That seems to be consistent with what other people have reported. Of course when I start getting the RHI payments, I expect those to offset the pellet cost to quite a large extent.
 
Any one looking into biomass could have a look at Treco website just started selling domestic biomass boilers . I install commerciall biomass and they sell the domestic version by guntamatic hope this helps


Sent from my iPhone using AVForums
 
A couple more things to consider, one being the many reports about breakdowns, and problems if you take winter holidays, the property will be without heat if no one is available to replenish the fuel.
 

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