Control systems

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.

An energy audit across its 27 dairy farms gave Landcorp Farming an insight into technologies to save energy and money. The resulting changes have reduced energy use by 9% and saved more than $50,000 in energy costs per year.

Higgins Aggregates operate several quarries in the lower North Island. At their Te Matai quarry, the water is sourced from an artesian well. A bore booster pump takes the low-pressure well water and supplies high-pressure water for plant wash-down hoses, dust suppression, and domestic use in the administration building and workshop.

An energy audit identified the opportunity for improved booster pump control.

Circulating chilled water or glycol systems are very common in many industries. The chillers often have internal temperature probes that result in unnecessary circulating pump running costs. Moving the temperature probe to another part of the system can be a cost-effective energy saving opportunity.

Read the case study below to find out how Millennium Plastics Ltd changed their chiller control system and reduced annual electricity use by 7,100kWh.