Wood Pellet and Wood Chip Boilers

Wood is a natural, sustainable source of fuel. If we burn it, wood will produce virtually no sulphuric emissions and is also CO2 neutral.

The CO2 that is produced through the burning of wood is all part of the natural carbon cycle, ultimately making a positive contribution to the environment.

As wood is the most common form of biomass fuel, it can take a number of different forms such as the likes of brash and sawdust. This fuel can be increased by processing these basic forms of raw waste, producing a higher value of biomass such as briquettes and pellets. Modern wood pellet/chip boilers offer both the warmth and comfort of regular wood heating methods whilst maintaining a high efficiency.

These boilers light themselves and can operate without the need for you to do anything yourself. An automatic fuel supply and the use of a thermostat allows you to just sit back, relax and enjoy the comfort of wood heating at the press of a button. Modern boilers are also self-cleaning, so you need not worry about the hassle of manual cleaning of your wood pellet/chip boiler. The fuel itself is generally a 6mm pellet, but can also be of 8mm in size. Its' moisture content is usually below 10%.

What are wood pellets?

Wood pellets are the biomass fuel used in wood pellet boilers and are made from natural wooden wastes with 1% bark content. This raw waste material is then taken and compressed into pellets. Pellets are formed by the compression of clean, dry sawdust or ground wood fibres. The process creates a valuable energy source that can be used in either industrial or automated domestic heating systems.

The main benefits of using wood pellets as a source of energy is their ability to flow easily during delivery allowing for ease of handling and transportation.

During the combustion process, the pellets are gradually fed into the chamber, where both the primary and secondary air are used in the combustion process in order to change the pellets in to gas through heat in excess of 500°C, providing a very clean product with minimal excess gas present - this is much lower than combusting fossil fuels.

Wood Chip Boilers

Wood chip boilers are also a good option for those who have access to waste wood and already own or are thinking of buying a decent wood-chipping machine. These boilers can often be more cost effective than that of wood pellet boilers.

They are usually more versatile than other boilers and can also take most wood pellet biomass and have also been known to take wooden logs when placed directly into the log boiler burning chamber.

These boilers are different from that of a pellet boiler in the way that the chip fuel is constantly fed into the boiler. Chip fuel isn't as free-flowing as wood pellets and therefore needs a mechanism to assist in the agitation of the fuel. It is placed into a drum and a specifically design arm stirs the wood chippings to maintain consistent flow of the fuel. Without this arm, the fuel could harden and solidify in the hopper.