AWARDS FINALIST: Fonterra – Waitoa Biomass Boiler Project
Fonterra says replacing an existing coal boiler with a biomass unit at its Waitoa plant has halved the site’s coal use and will reduce the group’s emissions by almost 3 per cent.
Earthworks for Project Kahikatea began in August 2022 and the new 30 MW boiler was commissioned late last year.
The $90 million investment achieved its business case in the first year of operation, and the project will set the delivery standard for other energy projects in terms of systems and processes, safety management and project culture.
Fonterra, one of the country’s three largest coal users, wants to be operating with net-zero emissions by 2050. It is aiming to halve its 2018 scope 1 and 2 emissions by 2030 and plans to eliminate the use of coal in its processing by 2037.
The co-operative says it began a programme in 2017 to identify ways to transition its three North Island coal-using sites – Te Awamutu, Waitoa and Hautapu – on to lower-emissions options.
Energy security
It says Waitoa was its third site to reduce coal use last year. As well as contributing to the group’s longer-term decarbonisation goals, it says Project Kahikatea also needed to deliver energy security for the site, given the condition of the coal boiler the biomass unit replaces.
Over 18 months, Fonterra collaborated with boiler installer Windsor Energy, Aurecon, Schick Civil and specialist steel fabricator Hendl & Murray Engineering to bring the company’s first large-scale capital investment in decarbonisation to fruition.
The new boiler uses a state-of-the-art bubbling fluidised bed combustion system, which is generally more efficient than standard grate type combustion systems.
It is expected to reduce the site’s annual emissions by the equivalent of 48,000 tonnes of CO2 – equivalent to removing 20,000 cars from New Zealand’s roads.
Fonterra says one of its strategic priorities is to be a leader in sustainability.
It says Project Kahikatea is a tangible example of that commitment and has also demonstrated to the wider industry that biomass can be produced at scale and can provide a secure and reliable fuel supply for the transition.
Big, complex
The project was big, complex, involved “new to Fonterra” technology and had a tight timeframe.
The co-ordination of multiple work-fronts requiring completion in parallel added to the complexity of the project.
There was also a requirement to maintain working order of all critical services while constructing and commissioning the new boiler into a fully operational manufacturing site – as well as ensuring that a new energy supply chain was established and able to supply the new boiler in time.
More than 1500 people worked on the project, and Fonterra says collaboration was the key to achieving and overcoming the challenges.
Pipebridges
Fonterra says the adopted methodology of having the pipebridges constructed and tested offsite was efficient. Accuracy was essential, with a tolerance of less than 6 millimetres to the pre-prepared foundations.
Ground conditions presented significant challenges, from excavations two metres below the water table in a notably wet winter, to an array of underground services.
Fonterra says the project team carefully managed approximately 450 interaction points with underground services through extensive hydrovacing and worked innovatively to bring industry insights into Fonterra to support business-wide improvements.
The Large Energy User Initiative of the Year category is sponsored by EECA.