Case studies

New technology is turning sludge from waste water into valuable bio-fuel with environmental and financial benefits for a Southland meat processing plant.

It's a bubbling fluidised bed boiler, well-proven overseas for its ability to handle low quality fuels. The 8.5MW unit was installed at Silver Fern Farms' Finegand plant by Energy For Industry under a build, own, operate agreement.

Fitting a variable-speed drive to a fan motor for a boiler has already saved Juken Nissho's Wairarapa mill $20,000 on a $50,000 investment made a year ago.

A thermal energy audit of South Island MDF producer Dongwha Patinna identified seven energy management opportunities, and a buyer for excess fuel produced onsite - which together could be worth up to $288,000 a year.

The University of Otago's Property Services division oversees the maintenance of campus buildings and grounds as well as new building construction. As the unit that keeps the University's campuses functioning year round, Property Services' energy use can be intensive. So when they were considering a heating upgrade, one of the key drivers was the ongoing cost of power. Renewable energy was the preferred option. But like any other organisation with limited budget, the final solution needed to make good business sense.