The concept of using biomass for heating has been presented here in Ireland as new technology and in my opinion installations have been over-complicated and overpriced.
Wood pellet boilers have been used in other parts of the world for many years and are much simpler in operation than oil boilers.
The idea of using buffer tanks with pellet boilers is something that I could never understand. We are told we need them to get higher efficiency. I would ask why then do we not use them with oil boilers where efficiency is more important because of the higher cost of fuel. The normal time for a pellet boiler to close down is 3 minutes and 1 minute to restart. The use of buffer tanks has little to do with efficiency and more to do with boilers having starting problems. The number of stop/starts is reduced when buffer tanks are used, but not eliminated. Any gain in efficiency will be lost in heat loss from the tanks.
Vari-flame:Boilers.
I spent many months looking for a system that would eliminate the need for buffer tanks and only found one company producing such a boiler. The output is completely variable 0-100%. An added bonus is that the water temperature is held steady, giving better conditions in the growing rooms. Steam boilers will maintain a steady pressure.
Cost:
The boilers are vertical design and the elimination of buffer tanks means that in many cases the boiler can be fitted in existing boiler houses:
Cost of 120 KW heating installation: Boiler £8,500, 22 tonne bin £3,500, Vacuum feeder £1,000, Installation (labour and materials) £2,000. Total £15,000.
Cost of 500 kg/hr steam installation: Boiler £13,000, Vacuum feeder £1,000, installation £2,000. Total £16,000.
So a 100 tonne/week farm can save 50% of heating and steaming costs for £31,000 investment and save 50% of their oil bill. You may qualify for grant aid or come under the RHI scheme.
We have assumed thatone bin and existing pipe work and water treatment plant will be used.
Parts are stocked locally and extended guarantees are available on the boiler.
