Biomass Boilers

Pistol1

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?

Stuart Wright

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.

Pistol1

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!

Stuart Wright

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.

Pistol1

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

Stuart Wright

Let us know what he says.  Would be interested in the kW output they recommend.

SteveCritten

What about ground source or air source heating?

Pistol1

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!

saintie1

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.

Pistol1

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.