Electricity efficiency

This is a guide to best practice in improving energy efficiency in boilers, steam systems, hotwater systems and process heating.

Topics covered by this guide include:

• What are the basic components of industrial steam, hot water and process heating systems?
• How can I tell if the system is functioning efficiently?
• What are the areas where systems can be improved to operate more efficiently?
• What energy source should I use?

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.

LinkPlas Ltd is a manufacturer of PET containers based in Albany. The company requires a reliable supply of cooling water to cool its injection moulding machine hydraulic-systems.

Their cooling tower is sized to achieve the required cooling duty on the hottest days of the year, and their fan ran continuously at a fixed speed, so much of the time the amount of water cooling far exceeded what was required.

Downer's asphalt plant in Penrose is the company's largest in New Zealand and produces road and paving products for distribution in the Auckland area.

An energy audit identified an opportunity for cost reduction for their fans, by using more efficient airflow control.

Read the case study below to see how Downer replaced the baghouse fan outlet damper system with a variable speed drive (VSD) and reduced electricity use by 67,100kWh per annum.