12 December 2013 | Steve Brambley
Did you know that approximately 30 per cent of the energy used in buildings is consumed inefficiently and unnecessarily?
In a manufacturing environment, two thirds of energy bills can be traced to motor-driven systems. Outside that environment, pumps, fans, air conditioning and ventilation, all of which are normally driven by electric motors, claim a significant slice of total energy usage. Energy efficiency is no longer merely an industrial issue, but also affects everything from supermarkets and schools to airports and office buildings.
Here are GAMBICA’s top five energy saving tips derived from industrial motor usage, which can also be applied in non-industrial sectors.
- Purchase costs versus running costs
When purchasing any type of equipment, industrial or not, it’s important to consider running expenses, as well as purchasing costs. Don’t let the slightly bigger initial investment of high energy efficiency equipment put you off. It will usually pay back quickly and save you more money in the long run.
- Correctly-sized, high efficiency motors
It’s important to establish what specification the equipment you’re purchasing needs to have, and stick to that plan. The temptation is to choose more powerful equipment than necessary, thanks to a “better safe than sorry” philosophy. But this way of thinking could significantly increase your energy bills because the higher specification equipment is much hungrier for electricity.
- Switch it off or turn it down – fixed and variable speed control
One of the best ways to save energy is by turning electrical equipment off when it’s not needed. Slowing a motor down to match the output required to achieve a specific task is also a great option for many applications. Using sensors and automation, many motors can be switched off when not need, for example in conveyors, escalators and industrial machinery.
For motors, the best way to control speed is to fit a variable speed drive (VSD), which can significantly reduce the amount of energy used, especially in pumps and fans. Similarly, in non-industrial applications, VSDs can be fitted on pump and fan applications in swimming pools, leisure centres, spas, hotels or public buildings. In fact, they find homes everywhere from agriculture to energy generation.
- System review
When deciding on an energy-saving plan, it’s important to look beyond the motor or central piece of equipment. The entire system, including pipe work, gearbox, pumps and fans should be reviewed. If you don’t apply energy-efficient philosophy to all the system components and the infrastructure, energy use could still end up very costly.
- Maintenance and management programme
Unfortunately, the quest for energy efficiency doesn’t stop after the equipment is purchased. It’s important to ensure regular maintenance is performed. For example, checking motor bearings and system condition is essential in any industrial application.
Finally, it’s essential to always be prepared for a breakdown, by having the necessary spare parts in storage. When breakdowns occur, make sure you don’t swap back to a low-efficiency system because it’s easily available or cheaper than the energy-efficient version.
☛ Steve Brambley is deputy director, industrial automation at GAMBICA, a national trade body that helps encourage energy efficiency in industry