Biomass Heating

What is biomass?

Biomass is also referred to as bioenergy or biofuels.  It is produced from numerous sources, but mainly from plant material or other waste organic matter.  It is either directly produced, or indirectly, via agricultural, industrial, domestic or commercial products.  There are three types of biomass fuel:

1. Forestry materials, where the fuel is a by-product of other forestry products
2. Energy crops, such as short rotation coppice (SRC) e.g. willow or miscanthus where the crop is grown for the purpose of biomass
3. Agricultural residues, e.g straw or chicken litter, sugar cane or maize

In addition to these three indigenous sources, biomass fuels can be imported, and this is usually in pellet form.  Sometimes biomass materials are categorised as “woody” or “non-woody”.

How does biomass work?

The products which comprise biomass are used to produce power, heat, steam and fuel.  There is more than one process to generate the power, but most involve burning.  Although it can be agreed that burning does mean the emission of various gases including carbon dioxide, they are produced in much smaller quantities than fossil fuels.

Plants capture the sun’s energy and store it by means of the photosynthesis which is released directly by burning or indirectly, which means that it is converted into products to become an intermediate stage.  They are converted to release the energy stored at a later stage, by a further process, such as refining, for example.  There are numerous processes of conversion.

By using biomass energy, the consumption of fossil fuels and therefore carbon dioxide emissions are reduced.  The difference between the burning of fossil fuels and biomass products is key to understanding why this is important:  when fossils fuels are burned, the carbon dioxide they captured via photosynthesis was millions of years ago, so the gas released is new.  Biomass products release carbon dioxide which was captured by its growth over a much shorter time span, meaning lower emissions into the atmosphere.

Heating a domestic property using biomass can be done in two ways:

1. Stand alone stoves providing space heating for a room.  Although these can be fuelled by logs or pellets, only pellets are suitable for automatic feed, because they are uniform in shape: logs would jam easily. Generally these are 6-12kW in output, and some models are fitted with a back boiler to provide water heating.
2. Boilers connected to central heating and hot water systems.  These are suitable for pellets, logs or chips, and are generally larger than 15kW.

There are numerous domestic log, wood chip and wood pellet burning central heating boilers to choose from, dependent on what use they will have or what budget is available.  For example, log boilers must be loaded by hand and may be unsuitable for some situations, whereas automatic pellet and wood chip systems can be more expensive.  Many boilers will dual fire both wood chips and pellets, although the wood chip boilers require larger hoppers so that there will be the same time interval between refuelling.

Is biomass heating suitable for my home?

The decision to use biomass as a source of heating must be analysed carefully to ensure that it works for the household.  Some of the preliminary considerations should be:

Commodity – what criteria is influencing the decision to use logs / pellets farm waste etc?

Legislation – is the household in a smokeless zone, for example.  It would be advisable to check if planning permission is necessary to make any intended alterations. The installation must comply with the relevant safety and building regulations.

Supply – where are the suppliers?  Will it cost too much to have a delivery of fuel if your home is a long distance from the supplier?  How promptly will they deliver, and is there a minimum order?

Storage – these products are bulky – is there sufficient space for both the storage of fuel and the burner and hopper?

Ventilation – biomass boilers require sufficient ventilation, which should be considered.

Maintenance – using a biomass boiler will mean carrying loads to the hopper regularly, and generally looking after the equipment.  A member of the household will need to take responsibility for this.

Cost – the cost of installation, maintenance and fuel should be calculated.

Savings – once the costs have been calculated, these should be compared with alternative energy sources and a conclusion drawn as to whether the savings will be sufficient.
Why should I use biomass heating?

There are both environmental and economic advantages to using biomass.  By using a local fuel source, transport miles are reduced and local investment is maximised.  It is also an alternative way of using energy without adding to the pollution problem as much as burning other matter would create.

It could be fun to plant trees or other vegetation to replace what you are using, which would bring an element of sustainability too.  The amount of biomass grown in twelve months is referred to as an annual increment.  By keeping production and consumption in balance, biomass can be viewed as a low carbon fuel.

What are the drawbacks for using biomass heating?

When using waste products, collecting them in sufficient quantities can cause problems and they may not be available all year round, which could disrupt the supply of energy.  Irregular supply may also risk price fluctuations in relation to supply and demand. Furthermore, if the reason for switching to biomass is to lower the carbon footprint, this is negated by the transportation of the fuel from abroad if the pellets are imported.

It is also fair to say that the fuel is burnt and therefore produces greenhouse gases.

If you are interested in biomass heating and energy, please complete the online enquiry form.  We will be happy to provide further information or a non-obligatory quote.

Although ongoing expansion plans are in place, the renewable energies team currently operates within a local area comprising Cheshire, Manchester, Liverpool, Shropshire and North Wales.  Whilst we welcome enquiries from other parts of the country, because we are happy to assist in the provision of information for renewable energy, we are unable to offer a service of delivery on a nationwide basis at this stage.