Re-use of surplus heat is vital to growth of Anaerobic Digestion
Anaerobic Digestion has the potential to provide a significant proportion of the UK’s renewable energy. Clearfleau is one of a limited number of UK-owned anaerobic digestion technology companies. It supplies medium sized anaerobic digestion plants, most of its plants are expected to produce below 500kW in electrical generation capacity.
Craig Chapman, Chief Executive of Clearfleau, commenting on the Government’s recent announcement said:
“We welcome the proposed increases to the Feed in Tariff rates announced by the Government on 18th March 2011. We support the new Feed In Tariff (FITs) but greater clarity is needed with regard to the proposed Renewable Heat Incentive (RHI)”.
Clearfleau expects to build several food sector plants in the next 12 months and has just been appointed by Nestle UK to install an anaerobic digestion facility at their Newcastle confectionary site. This and the other planned plants will generate less than 500 kW (electric output) and will qualify for the new FIT rates to be introduced later this year: 13p per kW for plants from 250 to 500 kW and 14p for those under 250 kW - compared to the current rate of 11.5 p for all plants under 500 kW.
Food processors generate considerable volumes of “trade effluent” as well as waste ingredients or co-products that are suited to anaerobic digestion. They are also well placed to use surplus heat in their production processes.
Chapman went on to say:
“We hope DECC will do more to encourage food companies to make efficient use of their entire energy output. While we welcome the introduction of the RHI, Clearfleau consider that all anaerobic digestion plants should be eligible for the RHI payment regardless of heat output; not just those under the 200kW limit.
At present many anaerobic digestion plants waste heat and the industry should be encouraged to re-use all surplus heat that is generated. It will not really be worthwhile food processors investing in the heat transfer technology, in order to use just 200kW of surplus heat.”
Looking to the longer term, medium sized anaerobic digestion plants, with an electrical output of less than 500kW, have the potential to make good use of available surplus heat and Clearfleau are suggesting that DECC should consider:
- Including all new anaerobic digestion plants (from July 2011) in the RHI for the first 200 kW of thermal energy that is used in one of the permitted uses.
- Extending the RHI to allow for a second payment band for anaerobic digestion plants that generate more than 200kw, to be introduced from 2012 onwards.”
From July 2011, unless all anaerobic digestion plants are allowed to claim the RHI, only very small ones (i.e. under 160kW electric) will qualify. Food companies will make sure that the surplus heat is used in their industrial processes, if there is a suitable incentive”.
Clearfleau fully supports the move to inject biogas to the gas grid that is also supported under the RHI and has several potential clients that may be interested in this option. However, it is important that incentives to use both heat and power on food processing sites are also included in the UK’s policy framework for Anaerobic Digestion. Craig Chapman will be writing to Ministers to press this case and also working with the REA and ADBA to ensure that the incentives for renewable heat will work effectively.