Are biomass boilers the real deal?

Wood chips from the estate of Inverary Castle in Scotland provide the fuel for two biomass boilers.
Biomass boilers are an excellent renewable technology, but only in the right applications, says Mark Northcott.

We could slash a staggering 21 million tonnes a year off carbon-dioxide emissions by using biomass instead of fossil-based heat generation, according to Government estimates. This is equivalent to 5.7 million tonnes of carbon and represents a huge chunk of the current total UK annual emissions of around 161 million tonnes of carbon.

Impressive carbon saving is not the only environmental advantage of biomass. Emissions are also a key consideration — and, here again, biomass wins. A well set-up, clean wood-chip/pellet boiler produces less than 120 ppm of carbon monoxide and negligible amounts of SO2.

One of the best things about biomass, however, is the big return on the energy needed to obtain the fuel. If you put 1 kWh worth of effort into supplying woodchips you get 20 kWh of heat back — 20 times as much back as you put in. The fuel can also be sourced locally, reducing the environmental impact associated with transport and contributing to security of supply.

However, before a consultant considers biomass as a viable option for a project, it is important that they examine several crucial factors, but there are many applications in which biomass makes perfect sense. For example, two 145 kW Remeha biomass boilers manufactured by Gilles in Austria are playing their part in ensuring that ASDA’s recently built store in Bootle is one of the most eco-friendly supermarkets in the UK.

ASDA’s determination to achieve zero waste to landfill by the end of 2010 means that its new £27 million supermarket incorporates a variety of innovative technologies, reducing energy use by 40% and halving carbon emissions compared with a standard new-build store.

Modulating, fully controllable and automatic Remeha biomass boilers can be fully integrated with conventional boilers. In Bootle, the biomass boilers, fed by wood pellets, complement a ground-source heat pump and heat-reclaim system. High-temperature operation and the length of time the gases remain in the biomass furnace guarantee clean combustion, further contributing to the excellent environmental standard set by the new ASDA store.

Likewise, when deciding to update the heating arrangements to the family’s private apartments at Inverary Castle, the 13th Duke of Argyll chose to investigate the ecological advantages of a biomass system. Consultation with Irons Foulner of Edinburgh resulted in the installation of two Remeha 145 kW biomass boilers, also manufactured by Gilles.

Remeha, biomass
Two biomass boilers in ASDA’s Bootle store are contributing to a halving of carbon emissions compared with a standard new-build store.

Located in a remote boiler house and connected to the castle by underground heating mains, the biomass boilers provide heat and hot water to around a third of the castle. The boilers are fed by wood chips from the Inverary Estate, eliminating both the carbon emissions and costs of fuel transportation.

Fuelled by wood chips or wood pellets, Remeha biomass boilers are modulating, fully controllable and automatic. The combustion chamber is lined with (replaceable) ceramic radiant fire-bricks and designed for high-temperature operation. Clean combustion is assured by the high temperatures and length of time the gases remain in the furnace. Maintenance is made easier by an insulated door that swings open fully to allow ease of access for boiler flue cleaning.

Using biomass for energy production also reduces the need for landfill. Landfill produces gases such as methane, a greenhouse gas 21 times more potent than carbon dioxide. Collecting forest waste to fuel biomass boilers helps prevent forest fires, and UK sourced biomass can offer local business opportunities and support the rural economy.

Mark Northcott is director — commercial products with Remeha.

Related links:
Related articles:



modbs tv logo

New Sustainability Director for Wates Group

Wates Group, a family-owned development, building and property maintenance company, has appointed Cressida Curtis as its new Group Sustainability Director.

Domus Ventilation appoints new contractor sales managers

Ventilation systems manufacturer Domus Ventilation has announced the arrival of three new Contractor Sales Managers.