Bioenergy

Waste was one of the first considerations for Southern Pine Products when it started manufacturing MDF (medium density fibreboard) products.

The company opted to install a briquette press, which turns MDF dust into combustible briquettes for boiler fuel.

Moffatts Flower Company, a greenhouse complex only 5 km from Southern Pine, now buys all the briquettes the company produces.

The saving in Southern Pine's waste disposal costs is projected to be $180,000 a year and annual revenue from briquettes is projected to be around $25,000.

A 50kW wood pellet-fired boiler is proving considerably cheaper than electricity for heating the Bay of Plenty‘s 30 bed Titoki Healing Centre.

Fully automated and fed by a 3-tonne hopper topped up by the truckload, the system operates virtually hands-free.

Installation cost around $80,000. That compared more than favourably to the other main option, heat pumps, at around $90,000. Running costs are even more competitive at about $4,400 annually, almost a third of the costs estimated for running heat pumps.

Cogeneration (or combined heat and power) can be a good solution for sites with a significant heat and electricity demand. This study looks at the feasibility of cogeneration and the Craigpine sawmill in Winton.

Ashburn Clinic in Dunedin commissioned an ETA Hack 200 195kW woodchip boiler to replace an old LPG/coal boiler. Switching from gas to woodchip, with a secure wood fuel supply agreement, had a 1.6 year simple payback. EECA provided a $100,000 Wood Energy grant towards the project. A buffer tank was also installed to optimise boiler operation and the existing coal bunker was cost-effectively renovated into a wood fuel store.