What Is Biomass?
Biomass is biological material derived from living or recently living organisms such as plants or plant-derived materials. It can be used directly via combustion to produce the heat, or indirectly, after converting it to various forms of fuel. The largest biomass energy source is wood in the form of logs, pellets or wood chips.
The full range of biomass fuels also includes animal, food, industrial and municipal waste. Biomass can be transformed into various forms of energy, such as methane gas, ethanol and biodiesel. Burning biomass releases most of the energy as heat that can be utilised to heat homes, generate electricity or as a fuel for vehicles.
Unlike coal, which can take millions of years to form, biomass is relatively environmentally friendly and sustainable. It can be obtained very quickly by replacing or growing new plants or trees. Biomass is also known as a carbon neutral form of energy because plants absorb as much carbon dioxide from the air when they grow, as they release during the burning process. It supplies us not only with the energy but also reduces waste we would otherwise need to dispose of.
Biomass is one of the most popular fuels for boilers. If you're considering to install a biomass boiler or any other kind, you just have to fill in the form on the right, and you'll receive quotes from boiler suppliers. It's quick, easy and free.
How Does a Biomass Boiler Work?
Wood is not a new type of fuel, but the technology has improved considerably to make it more efficient. Domestic biomass boilers can be a budget saving replacement for gas or oil boilers and provide you with space heating and hot water. Most of the modern boilers are fully automatic, and they control the amount of fuel and air produced in the combustion chamber.
Biomass boilers work by burning wood pellets or chips in order to generate heat for your home or building. To minimise transport and delivery costs of fuel, manufacturers recommend ordering a year’s supply of fuel. If you cannot provide large storage space, wood pellets can be delivered on pallets of 10 kg bags.
Wood fuel is automatically fed into the boiler from the storage area where an electric probe ignites the material. The produced heat is monitored and controlled by thermostats that adjust both fuel supply and fan speed. The hot gasses produced during the burning process flow to the heat exchanger where the heat is passed into the water used for the heating system. Water circulates through a central heating system while heating the property.
Which Wood Fuel Is the Best for Biomass Boilers?
Wood fuels will need more storage space as compared to fossil fuels (oil or LPG). The most frequently used types of wood fuels are logs, wood chips and wood pellets. While wood chips and pellets are commonly used in automated systems, logs are dependent on human input and they must be manually fed into the boiler. If the wood contains too much moisture or is not adequately seasoned, smoke and tar will be formed during the burning process.
Wood pellets are composed of compressed sawdust and wood shavings. They are 100% natural, renewable and easy to use. Their energy content is higher than logs or wood chips so they have a higher energy content and do not require large storage space. Wood pellet systems are small and require minimal input from the user.
Wood chips are a solid material made by cutting larger pieces of wood. The advantage of wood chips is low cost, but their efficiency cannot reach a high level such as wood pellets. Wood chips require less energy for manufacturing, processing and transportation as compared to other wood fuels. In addition, when harvested through sustainable forestry practices, wood chips are viewed as a renewable energy source.
Before investing in a biomass boiler, it is important to think carefully about storage space, supply and handling of fuel. To maximise the efficiency of your equipment, it is essential to choose the right type of fuel and get the moisture content of the fuel right. Wood chips and logs will have a higher level of moisture (25%) while wood pellets need to be dryer (8%).
Benefits of Biomass Heating
- Affordable heating fuel: even though the prices of wood fuel are not constant, it is cheaper than other heating methods.
- Financial support: wood fuel boiler system could benefit from the UK’s Renewable Heat Incentive (RHI).
- A low carbon option: the carbon dioxide emitted during the burning process is equivalent to the amount absorbed over the months and years that the plant was growing.
- Savings: biomass heating will contribute to both savings in carbon dioxide emissions and financial savings.
- Support for local business: biomass can be sourced from within the UK, which offers a steady supply and helps local and national businesses.
- Low maintenance: most of the modern biomass boilers require very little maintenance. In fact, some of the boilers can be fully automated without any user input. However, boilers should be serviced and inspected by a qualified service engineer on a yearly basis. If the boiler is not fitted with automatic flue cleaning, then regular cleaning and discharge of the ash bin are required on a weekly basis.
What Are the Best Applications for a Biomass Boiler?
Biomass boilers should not be switched on and off such as fossil fuelled boilers. They need to operate continuously in order to achieve their highest efficiency.
How Many Biomass Boilers Are Currently Installed in the UK?
Several hundred biomass boilers in the UK have been installed in the variation in size from 50 kWh to the 220-megawatt system installed at a power station. Considering all the benefits of a biomass heating system, the number of installations is constantly increasing.
How Will My Fuel be Delivered?
Wood fuel can be supplied as logs or as bags of pellets. Wood pellets are often tipped and can be blown from the delivery vehicle equipped with fans for this purpose.
Do I Need Planning Permission to Install a Biomass System?
Planning Permission is not required for boiler installations in houses but it may be obligatory for installations in historical buildings or sensitive locations.
Do Biomass Boilers Produce Smoke?
A well designed and highly efficient boiler should not produce any smoke during the burning process unless in the case of a high level of moisture in the fuel.