Sustainable Heating

Wood fuelled heating

Wood fuelled heating systems can provide your property with heat and hot water in a cost-effective, sustainable manner. They can be used alongside your existing boiler or can replace it altogether. The wood fuelled heating systems that Positive Footprint can provide include log, chip and pellet boilers. They are particularly appropriate in older properties with plenty of fuel storage space. Being able to supply your own wood is advantageous.

Wood fuelled heating systems are often combined with solar thermal systems, as this means you can alternate between using the solar thermal for water heating requirements in the summer and the biomass burner for heat during the winter. This provides the chance to replenish the wood stock during the summer months while the solar thermal takes care of heating the water.

Log multi-fuel Boilers

Log multi-fuel boilers are run on logs, chips and pellets and have a fully automated control system, ensuring that they are burning efficiently. They are well suited to larger, older houses that require significant heating. Log multi-fuel boilers are very robust boilers and you can expect not to have any troubles with it.

Pellet Boilers

Pellet boilers are the most efficient and automated of the biomass systems. They come with self-feeding systems and fully automated controls, which have the capability of being set from your mobile phone. A pellet boiler can replace your existing boiler completely.

How they work

Biomass Boilers use wood as their source of energy. Wood is considered a renewable energy resource because trees absorb CO2 as they grow. Carbon-neutral wood-fuel comes from sustainable, re-planted sources or from clean waste wood.

Biomass options

A traditional log-burner with integral water boiler for central heating if required. Log stoves can be one of the most cost effective forms of renewable energy. Installed costs are reasonable at between £1,000 and £2,500. Provided you can obtain a reasonably priced (or free!) good quality wood-fuel supply, then returns can be impressive. But do bear in mind that log stoves are not the lowest maintenance option!

An auto-feed wood-pellet boiler is a more convenient and controllable alternative to traditional log stoves. Enough wood pellet fuel can be stored in the stoves for up to 3 days burning.
Wood chip boilers are not often seen at domestic scale, and as most require a 3-phase electrical power supply are more common in larger applications such as schools, farms or industrial buildings.

For biomass, fuel cost, quality and storage issues are all important.

Things to consider

Can you obtain good quality fuel at a reasonable price? Wood fuel prices range from around £60 per tonne for seasoned logs. Pellets cost around £180 per tonne. Buying in bulk is the cheapest option.

For pellets, expect to consume between 3 and 5 tonnes per year. Do you have enough storage space for your fuel? On average, one tonne of fuel will need the same covered space as a typical garden shed.

What’s your budget?

A typical log burner with boiler costs around £2,500 installed while pellet boilers are available for around £5,000 depending on size.

What do you need?

You should have suitable storage space for the fuel. On average, one tonne of fuel will need the same covered space as a typical garden shed. The more often you order fuel, the less space you will need, but on the other hand, buying in bulk can be cheaper.

It is beneficial to be able to locate a good quality fuel source at a reasonable price. Wood fuel prices range from around £60 per tonne for seasoned logs. Pellets cost around £180 per tonne. Buying in bulk is the cheapest option. For pellets, expect to consume between 3 and 5 tonnes per year.

You need a vent which is specifically designed for wood fuel appliances. Your existing chimney can be fitted with a lined flue, which is relatively inexpensive.

You need to live an area that is not a smoke control area. To find out if you’re area.

What you can expect to earn

If you are replacing solid fuel or electric heating you are likely to save between £170 and £390 per year. Unfortunately you are less likely to save if you are replacing a gas heating system, but you will be eligible for the proposed Renewable Heat Incentive (RHI).

The Renewable Heat Incentive is due to be launched in June 2011. It is designed to encourage the uptake of renewable and low carbon heat technologies by providing a financial incentive. The details of this are due to be released at the end of 2010. See Grants and Tariffs for more info.