Case studies

Christchurch specialty meats producer Verkerks is paying for a lot less energy after taking a fresh look at how it generates heat and processes waste.

By converting the boiler to burn tallow, a meat processing byproduct, Verkerks will likely cut their energy costs by $150,000 a year.

The boiler at the company's processing plant produces steam for heating the smoke houses and fermenting rooms, and water heating.

Until recently the boiler operated only on diesel, consuming around 7,000 litres - and thousands of dollars - every week.

The Mt Maunganui-based facility has installed a dual-fuel boiler that has reduced natural gas usage by utilising waste products from their factory. Now they are burning all their waste vegetable oils and tallow. The new boiler reduces their CO2 emissions by 1,378 tonnes per year.

Ernslaw Bio-Energy's new mobile wood chipper means the Central Otago company is well-placed to take advantage of an expected increase in the use of wood-chip boilers.

The company bought the $250,000 German-made Heizohack HM10-500 KT chipper and the John Deere 7530 tractor which powers it in 2008 with the help of a business grant from the Energy Efficiency and Conservation Authority.

Dairy farmers and technical experts share their experiences across four demonstration projects using a variety of solar water heating and waste heat recovery systems to reduce energy costs in the dairy shed.