Heat from waste wood
Generating heat from waste wood seems like good common sense but before launching into an investment that is going to turn your pile of off cuts, or old pallets into a warm workplace, it is well worth taking a few minutes to read into the subject - it will save hours later.
You may well have heard that 'biomass' is becoming very rapidly bocomming the fuel of choice for heating. This is small part is due to 'environmental' reasons, but much more because the government incentives to generate heat from biomass are very generous. The renewable heat initiative, known as RHI basically ensures that organisations get paid by the State to generate heat by burning biomass. But as you would expect there are a number of hoops to jump though in order to get on the scheme.
At this point it should be said that RHI is not a specialist subject for Puravent, however we can say with confidence that at this point in time, using heaters that heat air directly with biomass do not qualify for RHI. The suggestion is that this is because heat output on air is difficult to measure. (how little they seem to know and understand!). RHI is only applicable to systems based on boilers, where the heat energy generated can be measured on water.
Puravent supply a number of space heaters that are fueled by biomass that do not qualify for RHI, because they delivery their heat onto an air flow and not a water flow. They are much simpler to install and deliver a flow of warm air, meaning that there are fewer stages to space heat than with a water based system.
Heat from waste wood - The regulatory hoops
If you simply want to generate heat from waste wood, without going through the hoops and complexity of getting RHI then these heaters are the answer. However there are still some points to be borne in mind...
In both commercial and domestic properties, the installation of heaters burning biomass, whether for heating water, or for heating air is covered by the building regulations. Part J (Heat Producing Appliances) contains all the information you need covering the design and installation of the heater and its flue. But the most important thing to realise is that you need to notify your local council building inspector and get them to inspect and approve the installation
Heat From Waste Wood. - The Hardware
Puravent offer currently offer 3 models of wood fired space heater that can burn unprocessed wood These are all manufactured in Spain by Met Mann. They are made of steel plate and have combustion chamber, ash pan, and a combustion gas/air tubular heat exchanger. There are 2 outputs, 50kw and 100kw. The heaters come with a fan attached that drives air through the heat exchanger into the workplace. When fitted with a centrifugal fan it enables the heater to be connected to a modest run of duct work so that the warm air can be delivered to other areas in the building. The 50kw model with an axial fan is suited only to delivering warm air to the room in which the heater is located, (i.e. no ducting)
Puravent also supply the Biomann range of pellet fired space heaters which can burn a variety of fuels such as processed wood pellets, olive stones etc. Because of the complexity of the system, including hopper vessel, conveyor, fuel feed and controls etc. these machines are a fair bit more costly. Like the ECOPOL heaters , they warm air rather than water so are not boilers, therefore not eligible for RHI.