Saturday, December 2, 2023

Electric boiler to cut emissions

Avatar photo
Synlait Milk’s emissions savings after 10 years of its electrode boiler at the Dunsandel plant will be equivalent of emissions from 9600 houses.
While Synlait’s revenue continued to march higher, hitting $1.66bn in the July 2022 year, margins have been getting squeezed.
Reading Time: 3 minutes

The change is part of the company’s ambitious target to reduce greenhouse gas inventory, both in its own activity and the on-farm emissions of its farmers.

Off-farm it wants to reduce total greenhouse gas per kilo of product by 50% by 2028 from the 2017-18 base measurement of 1.13kg carbon dioxide equivalent.

On-farm the target is a 35% reduction from the base figure of 11.87kg of carbon dioxide equivalent a kilo of milksolids.

Synlait has provided all its supply farmers with their gas emissions profile since the 2017-18 season. A new incentive for reducing gas levels has been included in the company’s Lead With Pride farm assurance programme.

Farm emissions make up 83% of total group emissions.

Synlait’s own contribution of 17% gives it large emitter status because of its energy-intensive manufacturing processes.

Its new strategy is aimed at having a net-positive impact on the planet, with commitments on-and-off farm to eliminate water degradation, remove waste and improve animal and ecosystem welfare as well as the gas reductions.

The overarching goal is to work alongside farmers to boost farming systems towards being regenerative, Synlait says in the latest annual report. 

Taking action on the climate crisis is an absolute necessity.

The boiler installed for process heat in the new advanced liquid dairy packing system at Dunsandel is the first at the plant to be powered by electricity. The others are coal-powered but the company says it plans to move away from coal.

Synlait has estimated total on and off-farm emissions in 2018 were 912,731 tonnes of carbon dioxide equivalent.

Most, 755,583/t, were produced on-farm and included 119,758/t of carbon dioxide, 442,268/t carbon dioxide equivalent of methane, and 193,559/t carbon dioxide equivalent of nitrous oxide.

The off-farm count was dominated by 108,301/t from coal use, 30,162/t from sea freight and 6923/t from electricity.

The report said New Zealanders have rightly become increasingly concerned  about the degradation of waterways. 

Synlait is determining baseline figures for its water use and having them independently reviewed. The goal is a 20% reduction in water use per kilo of milksolids by 2028 and a 45% reduction in nitrogen loss to waterways. 

Synlait is providing farmers with access to environmental advisers for guidance on how they can be achieved through changed irrigation practices, modernising equipment and soil, fertiliser and feed management.

Off-farm, the goal is also a 20% reduction in water use by 2028 and a 20% improvement in the quality of waster water. More meters are being installed at Dunsandel for precise water-use monitoring.

Process heat, energy in the form of steam or hot water, is used to turn fresh milk into powder and to pasteurise and sterilise milk at Dunsandel.

With the electrode boiler electricity flows through electrodes submerged in water, releasing steam as contact with liquid is made. It is very energy-efficient at scale and is on-demand, in that water can be heated from cold in five minutes or from standby in about one minute. The report said the electrode boiler is 99%-efficient and up to 30% more efficient than coal boilers.

The infrastructure and running costs are significantly higher than coal but the business case assumes an increased cost for carbon over the next 10 years.

It is the electrode boiler’s carbon savings over that period that are estimated to roughly match the output from those 9600 houses.

The report said Synlait is also planning to improve the outside environment through whakapuawai – meaning to blossom, develop, flourish, prosper or thrive.

About 15ha of grazing land behind the Dunsandel factory will be planted in native trees and shrubs in a development to include walking tracks and wetlands. 

Synlait is working with farmers to identify on-farm areas that will benefit from regeneration projects.

It is also forming partnerships to restore community areas. One of the projects is likely to be Waihora (Lake Ellesmere) with extensive planting and wetland development planned at Cooper’s Lagoon. 

People are also reading