Since the
closure of the Feed-in-Tariff (FIT), the Renewables Obligation (RO) and the
Renewable Heat Incentive (RHI), support for anaerobic digestion (AD) with combined
heat and power (CHP) has weakened. For some early adopters, RO accreditation is
coming to an end and many of the early FIT-supported projects have less than 10
years of support remaining. This, combined with the policy focus shifting to
biomethane for decarbonisation of the heat and transport sectors, has led to an
increase in interest in CHP conversions. However, conversions are not currently
eligible for support under the new Green Gas Support Scheme (GGSS). NNFCC have
recently worked with CNG Services Ltd to deliver a study into biomethane
potential from CHP conversions, funded under a Network Innovation Allowance
(NIA), with support from Northern Gas Networks (NGN), Wales & West
Utilities (WWU) and the Energy Innovation Centre Ltd (EIC).
Considering
options for improving performance, profitability and environmental impact of existing
assets and resources provides a significant opportunity for the sector, to
prolong the life of ageing developments and to strengthen existing activities. NNFCC
were tasked with evaluating the potential of converting CHP sites for
biomethane production, to quantify the scale of the opportunity, and to explore
novel ways of connecting and injecting gas into the network.
As part of
this work, NNFCC assessed biogas sites across the UK to quantify the scale of
the opportunity at regional and national level, and to identify biogas
production clusters that warrant further investigation. NNFCC monitors the AD
market in the UK and publishes an annual ‘AD Deployment in the UK’ report which is underpinned by a database of all operational and planned
AD facilities in the UK. With the aid of mapping software, NNFCC’s AD database
was used to map all AD CHP sites and identify potential clusters, and a series
of criterion was developed to determine likelihood of switching from CHP to BtG
in the next 5-7 years, based on scale, age, type and location of plant.
NNFCC also used
Excel modelling tools to perform a comprehensive cost assessment. A model was developed
to determine whether conversion was economically viable at individual
site-level, to understand the level of support required to make conversion
attractive, and to evaluate the technical and financial viability of developing
biogas clusters with a common upgrading and injecting point.
As a result
of the work, the client got a clear understanding of the scale of the
opportunity and the associated costs under different scenarios. The reports
have been published here:
Stage 1
Stage 2
Stage 3