Rising electricity prices and environmental concerns have driven an ongoing trend towards energy efficiency. Lower electricity consumption can translate into a significantly lower lifetime cost for a system, even the upfront capital cost is higher. Let’s take a look at some of the ways you can save energy in your process.
Variable speed drives
VSD’s (also known as variable frequency drives or VFD’s) are becoming increasingly common across many industries. Many processes don’t require pumps or other motors to be running at 100% speed constantly. By adjusting the motor speed to the minimum required for the process to continue, huge power savings can be realised. If the process requires more power, the VSD can quickly ramp up the motor speed to suit.
While VSD’s are expensive compared to a traditional direct on-line starter, the upfront cost can be far outweighed by the lifetime energy efficiency savings.
Smaller is better
Obviously a smaller motor uses less energy than a larger motor at a given load. By selecting the smallest motor to suit your application, you can save both upfront and ongoing costs. Smaller equipment translates to less heat: you can also save energy and money in cooling equipment.
Smart power monitoring
You can’t manage what you can’t measure, and with today’s power monitoring equipment it’s even easier to directly monitor your process power consumption in real time. Power monitoring data can even be fed to the process PLC to allow it to dynamically minimise energy consumption where possible.
Any process produces some waste energy, often in the form of heat or motion. By capturing this waste and turning it into useful energy, further power savings can be made. For example, the waste heat produced by one process could be used for pre-heating another process; or a pressurised waste line from a water treatment process could be used to turn a turbine to boost the pressure on the inlet side.