Biomass WID 2017-09-08T09:30:03+00:00

Biomass WID

Over the past few years the biomass sector has grown significantly. The commercial sector has embraced this technology and has already received billions of pounds through the Governments
Renewable Heat Incentive (RHI) scheme.

The Government has recently renewed its commitment to the RHI by announcing the reformed RHI which will introduce some modifications to the scheme but in essence the scheme remains very similar insofar as it provides businesses with a cash incentive payable for every kilowatt hour of energy generated from renewable heating technology for 20 years index-linked and guaranteed once accepted onto the RHI scheme.

Many businesses across the UK have installed biomass systems to provide space and process heating. However, the majority of these installations have been designed to run on virgin wood chip or wood pellet fuel but it is possible to obtain the RHI for biomass systems running on waste wood.

The regulations regarding the definition of ‘waste wood’ and the emissions controls required when burning the various categories of ‘waste wood’ are complex but Biomass Trigeneration are able to assist with initial guidance, designing and providing a technical solution to suit individual business opportunity / requirements.

Biomass Trigeneration Boiler

What is waste wood?

The principal criteria for determining the regulatory status of a biomass combustion facility is whether
or not the fuel is classified as a waste. Whether a material is waste or not is determined by reference to the European Framework Directive.

Virgin Timber and Clean Biomass

The combustion of virgin timber and clean biomass fuel is regarded as solid fuel combustion and is regulated accordingly under the  environmental Permitting Regulations or the Clean Air Act 1993, depending upon the thermal input of the appliance.

However where virgin timber is mixed with waste timber, or any other waste, the mixed load is classed as waste wood.

Non-Virgin Timber and Waste Wood

Non virgin timber such as off cuts, shavings, chippings and sawdust from the processing of non-virgin timbers (whether untreated or treated) are waste wood. Untreated non-virgin waste wood, despite not having been treated with any chemicals, is waste wood. Treated
non-virgin timber is any timber that has been treated (e.g. to enhance the performance of the original wood) or made into panel board of any sort is waste wood.

Any biomass material that is ‘waste’ would be subject to the Industrial Emissions Directive (IED) regulations as applied to the waste  incineration process. However the IED provides for exemption of certain biomass materials and these are not subject to the operational requirements of the IED and, dependant on the net rated thermal output of the installation, can be regulated by the Local Authority.

Grade A

Waste Wood Grade A

“Clean” recycled wood – Material produced from packaging waste and secondary manufacture including untreated process off-cuts, scrap pallets, packing cases and cable drums.

Grade B

Waste Wood Grade B

Industrial feedstock grade – May contain Grade A wood together with other waste wood from construction and demolition activities, transfer stations and solid wood furniture manufacture.

Grade C

Waste Wood Grade C

Includes Grade A & B wood plus material coated and treated with preservatives typically including a high content of panel products. Suitable only for IED Chapter IV Compliant Boilers.

Grade D

Waste Wood Grade D

Hazardous waste – This includes all grades of wood including treated material such as fencing and trackwork and requires disposal at
special hazardous facilities.

What Type of Boiler is Required?

It is possible to burn Grade A, or possibly Grade B, waste wood in a standard industrial biomass boiler (subject to any additional emissions controls to comply with permitting requirements) but Grade C (or possibly Grade B) will require what is known as a WID compliant boiler.

Although the WID regulations have now been amalgamated into the IED a boiler that complies with the requirements of the IED (to hold the combustion gases at a temperature of 850°C for a minimum of 2 seconds) it is generally referred to as a WID compliant boiler. An IED (WID) compliant boiler is larger and more expensive than a standard industrial biomass boiler.

Biomass Trigeneration Boiler

Frequently Asked Questions

When you know what type of material you have access to and wish to use as a fuel you will need to select a boiler.

Does burning waste wood affect my RHI payments? 2017-09-06T16:08:37+00:00

If your RHI application is based on an RHI emission certificate then you need to ensure this certificate specifically lists the material you are using in your boiler. If you do not you will be breaching the RHI terms and you may be fined and even asked to repay your RHI payments.

Your annual RHI declaration asks whether you have made any changes to fuel or your system. You must be open about any changes you make to your fuel. Again, not doing so could be regarded as a breach.

Are there situations where I would be exempt from needing a permit? 2017-07-17T14:42:04+00:00

Yes, there are exemptions granted in the EPR.

A U4 exemption (Ch2.Section2.4) is where you are burning the waste wood (grade A only) as a fuel, applicable if:

  • Material input <50Kg/hr and <400kW
  • <10T stored on site

A D6 exemption (Ch3.Section2.4) is where you are disposing of the waste wood (grades A, B & C only) by incineration, applicable if:

  • Material input <50Kg/hr and <400kW
  • <5T stored on site
  • You are only burning your own waste
If I buy waste wood from a BSL registered fuel supplier, do I still need a permit? 2017-09-06T16:09:56+00:00

Yes, EPR permitting requirements still apply, unless you have an exemption. Burning any kind of waste wood as a fuel (including clean grade A recycled, even if its mixed in with virgin wood) means you must have an Environmental Permit to do so, either form the local authority or from the Environment Agency.

What sort of records do I need to keep? 2017-07-17T14:43:09+00:00

I you are audited by OFGEM you will need to have evidence of wood fuel purchases (from BSL suppliers or you can also self supply) that corresponds with the kWh generated on your meter, irrespective of whether you have been burning virgin or waste wood.

You will need to find a way to measure and record the volume of fuel that you are using, which may require some thought for users of waste wood.

Can I burn waste wood in my biomass boiler? 2017-09-06T16:11:03+00:00

Possibly. There are operational and technical challenges to be met, not only to ensure correct combustion of the fuel, but also to ensure that the emissions are within the levels permitted for the type of fuel, the site location and the plant design.

You need to ensure the boiler manufacturer can guarantee the equipment will burn the material effectively (good emissions), efficiently, safely to maintain the boiler warranty and ensure the equipment retains its cost life cycle (burning some materials can significantly reduce the lifetime of the boiler and transport system components).

What is the difference between the Industrial Emissions Directive and the Waste Incineration Directive? 2017-09-06T16:11:29+00:00

The Waste Incineration Directive (WID) has now been amalgamated into the Industrial Emissions Directive (IED), but the operational requirements are unchanged. The IED states that a waste incineration plant must hold the gases generated by the incineration process at a temperature of at least 850°C for a minimum of 2 seconds. Typical industrial biomass combustion chambers hold the gases for
only approx. 1.4sec so a WID compliant combustion chamber should be specifically requested if this is what you need as a WID compliant boiler is both larger and more expensive.

It is important to enter discussion as early as possible with the EA or the local authority about the most appropriate equipment for the specific material at the site, or Biomass Trigeneration can do this on your behalf.