Biomass Boilers and Its Advantages

Biomass Boilers and Its Advantages

Biomass Boilers are boilers that heat the water of your household by burning biological matter, like, wood chips, pellets, logs, or other natural products. Instead of using gas or electricity or any other resource, these pellets are manually fed to the boilers, by hand, into a chamber where they are burnt. The hot gas and steam that are produced, then pass through a flue, to a heat exchanger, to heat the water in the central heating system and the excess heat is stored in a buffer vessel or thermal tank. They are usually joined with the existing space, underfloor, and water heating systems of the household.

What are the different types of biomass boilers?

Automated Biomass Boiler

Feeding the boiler with wood chips or logs can be fully automated. This means the wood chips are automatically fed into the boiler’s chamber. It is done through a large hopper or silo and it is the most efficient type of boiler. The silo can hold fuel for an entire year.

Combined Heat and Power Biomass Boilers

A combined heating and power unit produces both heat and electricity. These units are expensive for both small business houses or homes. These systems are suitable and used by big establishments because such buildings are more eligible for Government Tariffs, Renewable Heat Incentives, and Heat Premium payments.

Types of Biomass Boiler Hoppers

Biomass Boilers and Its Advantages..

Fully Automated Hoppers

The large boilers usually require specially designed silos, these are often designed as the requirement of the property or customized keeping the boiler’s requirements needed. Mostly, shipping containers are adapted by retro-fit applications to function as the hopper or custom-made large-scale hoppers can be purchased for the purpose.

There are five main types of hopper currently available:

Steel Hoppers –many different sizes available but can be fitted very fast.

Types of Chimneys and Flues

Types of Chimneys and Flues

The UK homes are mostly fitted with chimneys in them. While installing a biomass boiler, it must be kept in mind the difference between the combustion methods of an open fire and a biomass boiler system or stove.

Alterations to a normal brick chimney are required while installing a biomass system to replace the fire. The chimney needs to be modified to do the job of a flue else following problems can occur:

  • The brick wok in the chimney will be condensed by the flue gases and may damage the chimney.
  • Toxic gases can fill the household and cause a health hazard.
  • Fire accidents can occur because of the deposits blocking the chimney.

Installing Flue in the Chimney

A flue can be installed by a professional installer, in the existing chimney. Various methods include: a concrete or clay lining can be used or by inserting a steel tube from top to bottom, knowing the length required by the flue for efficient and safe functioning.

Stainless steel, or other metal or rigid flues, can also be installed if there are no chimneys in the establishment. Installations can be done by cutting through an external wall or the ceiling, out to the roof.

Buffer Vessel

The buffer vessel is a big, immersion heater tank, of different sizes, depending upon the system requirements, is a thermal store.  It is like a battery or capacitor for any biomass boiler. It permits a blast of heat a burst of heat while warming up the boiler and it balances the entire system.

This assists as the overall solution for your heating requirements and increases the system efficiency in the long run.

Maintenance for Biomass

Periodic maintenance of biomass boilers is required. This is done to maximize their efficiency and longevity.

  • Boilers produce ash that needs to be cleaned regularly to keep it ash-free. If the boiler does not have an automatic self-cleaning process, they need to be shut down to be cleaned. The burner too needs to be checked daily for any ash or residue and cleaned accordingly.
  • The boiler must be switched off from the mains in case it is checked from within. It should be allowed to cool down for safe examining. Extreme caution should be undertaken in the cleaning process and components.
  • The maintenance should include a check on the feed system too weekly to inspect the oil or any loose bearings. Any pellet or wood chip blocking the feed system should be removed the blockage should be avoided. This could build up compression n the feed system.
  • The soot on theheat exchanger and flue is cleaned during maintenance to prevent any blockages.
  • The stoves require to be ash-free too for optimum efficiency, after every operation.
  • Boilers that use logs, require the same cleaning process daily. This is to check if they are clean and there is no bed of ash. All the air vents, fans mustbe checked thoroughly once in three months so that no hindrance is faced by the boilers.
  • A professional technician must do thorough checking.
  • Appliances that have automatic cleaners have the flue cleaned by the compressor installed with air jets inside that are sent through the flue blowing the boiler soot. Though costly, this method increases the time intervals for maintenance. A biomass boiler lasts for more than twenty years if it is properly installed.

Cost of the Biomass Boiler System

Cost of the Biomass Boiler System

Biomass boilers are costly and three or four times more expensive than a standard fossil fuel boiler. The cost of the biomass systems is dependent on their types, manufacturers, and installers.

“An automatically fed pellet boiler for the average home will cost between £14,000 and £19,000 including installation, flue, fuel store, and VAT at 5%. A log boiler on average will cost between £11,000 and £23,000 and an individual pellet stove abounds £4,000 – £4,500. Fuel costs may vary dramatically but will generally cost less per kilo depending on the size of the order. These costs are for small and medium-scale biomass systems for homes and businesses. For example, a standard 3-bedroom home’s energy requirements would be fulfilled by a 15kW system.”

Benefits of Installing a Biomass Boiler

Reducing Carbon Emission

The carbon emissions of fossil fuels are more than the Biomass fuels, therefore, having the least carbon emission. produce a fraction of the carbon emissions. Biomass fuels unlike fossil fuels (oil & gas) have no carbons stored in them that could be released into the environment in the process of heating. When biomass fuels go under combustion, they only release the carbon inside the plant and not from the animal fats.

Some biomass boilers are smoke-free or fall w below the norms set up for biomass burners. The biomass boilers will have full accreditation for being eligible for smoke-free areas, soon.

“In March 2011 the Government published its policy for the non-domestic RHI, including the intention to introduce air quality emission limits for biomass boilers (including CHP) that participate in the scheme. Proposed limits were first published for consultation in 2010. These limits were confirmed earlier this year, with the maximum permitted emissions being 30 grams per gigajoule (g/GJ) net heat input for PM and 150g/GJ for NOx.” (Source: Google)

Save on Cost

The specifications of properties and various other co-related factors determine the amount of cost savings offered by the biomass boilers and the energy consumed by a household.

*The following fuel costs are assumed: that fuel costs per kW are as follows: Coal – 3.7p; Electricity – 14.4p; Gas – 4.5p; LPG – 8.2p; Oil – 5.9p.
**These figures assume a 3-bedroom, semi-detached home with insulation and an efficient pellet-fired biomass boiler. The calculations assume that the property’s annual energy demand is 20,000kWh and that the price of the wood fuel (pellets) is £185/ton.

It is obvious that biomass boilers are not only eco-friendly but also can be payback for a long-term investment.

Recyclable Ash

The ash produced by most biomass boilers is a compostable component. Since it is produced from wood pellets, it can be used as compost material for horticulture or disposed of in the landfills safely.

“Large biomass systems are also a viable option for the community and communal housing renewable energy projects and may be eligible for grants or subsidies from the UK government or the European Union. Community heating projects, which are more cost-effective due to the use of one large central boiler, are already very common in mainland Europe (especially in Scandinavian countries) but are becoming more and more common in the UK. District heating currently provides around 2% of the UK’s heat requirements.” (Source: Google)

Joining Biomass Boiler with Existing Systems

All biomass boilers can be joined with the property’s pre-existing heating system through radiators, water tanks, and underfloor panelling. Flues too can be placed inside the existing chimneys.

Installing a biomass system as a backup for your existing boiler, as a support, can also be done. Though the carbon footprint will not be reduced as much. All new or retrofit biomass installations must also comply with building regulations.

District Biomass Heating

District Biomass Heating

A central boiler room or heat source can help in distributing the heat to the entire district or communities through the networks of pipes, carrying the hot water, to a group of households or buildings. This is usually monitored locally or centrally.

“District heating currently provides approximately 1-2% of the UK’s heat demand. Research shows that there is a possibility that district heating could supply in the region of 14% of the UK’s heat demand, and be an extremely feasible and cheap alternative to both individual fossil fuel and renewable technologies, at the same time as reducing bills for the consumers involved. Community and district heating pipe networks are not specific to the technology used to generate the heat and so can connect to a range of sources of heat supply including CHP, biomass, energy from waste, ground source heat pumps, geothermal heat, or large power stations.” (Source: Google)

District heating pipes have more longevity and networking of pipes can be done depending on their suitability and economically best option.

“Large scale biomass heating systems producing around 450,000 kWh of heat per year, can cut heating costs by 50% over oil (24,000ltrs) and reduce CO2 emissions by 95,000kg per year.”(Source: Google)

Accreditations for Biomass Boilers and Stoves

“1. The UK’s Microgeneration Certification Scheme (MCS) is the main quality assurance scheme in the UK. It is worth saying though that MCS accredited companies must conform to stringent quality and safety standards to meet the Office of Fair Trading’s requirements.
If you wish to benefit from the RHI or RHPP then your proposed system must be MCS certified. This is certainly worth checking with the manufacturer of the system before going ahead with the install. The ISO 9001 is a standard to look out for, whilst not an essential certification scheme, it is world-renowned as a quality standard for construction companies.

2. The Renewable Energy Assurance Scheme (REAL) is a membership scheme that companies can sign up to, to indicate that they approve and follow its OFT-approved consumer code. The code aims to ensure a high standard of service for renewable energy install projects.

3. HETAS is another very important accreditation for your installer, especially if you are having a Biomass Boiler system installed or any large Biomass burning system.

HETAS is the official body recognized by the Government to approve biomass and solid fuel domestic heating appliances, fuels, and services, including the registration of competent installers and servicing businesses.

HETAS also approves products through a government-approved scheme of testing for solid fuel and biomass appliances. They also have a Quality Assured Fuel Scheme providing a recognized standard for biomass fuel quality. This approval scheme is designed to give consumers confidence in their fuel quality and its sustainability.

These are the main accreditations to look out for although there are many others. Some of the above are essential for some installation types.”

Conclusion

Considering your safety is the top priority, even the smallest of components installed for a boiler need accreditations and certifications. Therefore, it is worth asking your installer is necessary, so that the best professionals are chosen to install and work on your premises.