Carbon Calculation for Bioenergy

In order to receive renewable heat and power subsidies from government, projects must demonstrate that they comply with strict sustainability criteria, which requires them to calculate and report the greenhouse gas (GHG) impact of their supply chain. This can be particularly difficult to do with complex systems using multiple feedstocks and generating multiple outputs, such as anaerobic digestion (AD).

Shortly after the Criteria were introduced, an AD plant operator came to us seeking assistance with calculating the GHG impact of heat produced at their plant in order to comply with the requirements under the UK's Renewable Heat Incentive. The operator had previously struggled using Ofgem's Biomass and Biogas Carbon Calculator (B2C2). They did not find the tool particularly user-friendly and had to perform multiple runs due to the complex nature of their plant set-up. This led to erroneous calculations and ultimately resulted in their RHI payments being withheld.

At the NNFCC we have developed our own dedicated Biomethane & Biogas Carbon Calculator that is explicitly designed to deal with complex anaerobic digestion systems in a much more intuitive way. After using our tool with our guidance, this client was able to demonstrate the carbon intensity of heat produced from each of their feedstocks and re-submit their claims to Ofgem for RHI payments to be released after demonstrating compliance. Our calculator also allowed them to improve their own calculations, and to identify which of their feedstocks were at high risk of not meeting sustainability criteria in the future. They have subsequently changed feedstocks, providing them with even greater benefit.

Our calculator also allowed the client to simultaneously calculate the carbon intensity of electricity produced at their plant, which would have required an entirely new set of runs using B2C2. With sustainability criteria due to be introduced into the Feed-in Tariffs, our calculator is therefore likely to provide further benefit to the client in the future.

The NNFCC has conducted carbon calculation and sustainability compliance work not just for​ many individual projects, but also for major bioenergy and biofuel producers. In addition to providing UK scheme compliance tools, the NNFCC develops bespoke carbon calculators for operators seeking to comply with EU voluntary sustainability certification schemes such as International Sustainability & Carbon Certification.