Choosing the technology

The household waste treatment project is a key part of Buckinghamshire’s waste strategy for the future.  In March 2007, the County Council advertised in the official EU journal for bids to develop a thermal treatment process producing energy as a by-product for household waste leftover after recycling in Buckinghamshire. 

The advert did not specify the exact thermal technology to be used except to require the ability to produce energy from the process.  Independent technical advisers undertook extensive studies and scenario modelling before we took the decision to use thermal technology.  (The term ‘thermal treatment’ is a broad description of a number of technologies which include Energy from Waste (EfW) and autoclaving and also advanced thermal processes such as plasma gasification and pyrolysis.

The technology selection was taken after reviewing the best options for dealing with the complex mix that is household (black bag) waste in the volumes we produce in Buckinghamshire.  The criteria used included environmental issues, ability to obtain funding from banks and to help us meet our landfill targets, as well as being technically proven and reliable.  Technology options analysed ranged from mechanical biological treatment and anaerobic digestion to autoclaving and advanced thermal treatments.

The advert invited companies to bid for a contract to build and operate the plant.  Twelve firms initially expressed interest in the project in April 2007.  By the next stage in September that year, seven of those companies submitted outline proposals.  All bidders but one specified Energy from Waste as their bidding technology.  Four of those companies then dropped out of the bidding, leaving just three companies to go forward in June 2008 to submit detailed proposals for EfW plants: Covanta Energy, Veolia and WRG.  Following detailed evaluation against objective criteria, Covanta Energy and WRG were then selected to enter into final bidder stage. 

The Council had agreed to appoint Covanta Energy as its Preferred Bidder in September 2009, but whilst clarifying the terms of their appointment, the company made the Council aware of a commercial matter, which impacted on their bid.  As this might have affected the evaluation of the final bids the Council were legally required to re-open discussions with both Covanta Energy and WRG.

Following a detailed evaluation process which was carried out by September 2010 against the pre-agreed criteria, WRG were the highest scoring bidder, which meant Covanta Energy, with their facility at Stewartby, Bedfordshire had not been selected.
In November 2010 Cabinet decided to award Preferred Bidder status to WRG for the 30 year contract to build an EfW facility to treat the county’s residual household waste. 
WRG are a Spanish owned organisation and are waste management specialists operating an array of services across the UK.  Their main facility would be based at Greatmoor, near Calvert and use two waste transfer stations at High Heavens HWRC in High Wycombe and Amersham HWRC.

Currently there are 24 EfW plants operating successfully in the UK now.  In 2005 there were 418 EfW plants operating in 18 other European countries.  These European sites process around 58.5 million tonnes of waste a year.  They generate enough energy to supply about seven million households with electricity and 13.4 million households with heat a year.  To provide the equivalent energy from conventional power generators would mean that between six and 32 million tonnes of fossil fuels (gas, oil hard coal and lignite) would have to be used (CEWEP).