Case studies

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.

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.

Pacific Wood Products (PWP) installed Ecogate control systems on their extraction fans. Through the use of air flow control gates and a variable speed drive connected to each fan that adjusts to meet the actual workload, PWP reduced their energy use substantially.

Energy savings were immediate from week one. The system will be paid for in be just over 4 years, and long-term they benefit from lower energy bills. Equally important, PWP will cut its annual CO₂ emissions by 45 tonnes.

With its future at stake, New Zealand Foam Latex needed an economically viable and environmentally friendly fuel to produce steam needed to manufacture their products - all made from foam.

Coal was cheap, from $6.10/GJ. But emissions and the costs of mitigating them ruled it out. Diesel and LPG would cost over $30/GJ.

Wood was cost-effective and clean-burning. A variety of sources helped assure reliable supply - forestry hoggings, timberyard residues, left-over pallets and demolition, even dunnage reclaimed from shipping.