Improving the energy efficiency of industrial applications is a major concern for most manufacturers. Owner-director of CP Automation, Tony Young, cites the benefits of regenerative braking and how this technology can be used to improve the efficiency of industrial applications, including motors and drives.
Heavy engineering, transport, mining, the elevator market and other applications that involve a lot of braking and restarting can benefit from regenerative braking: an electric motor generates energy that can be used immediately in the local grid and thus reducing the draw from the mains supply.
In effect, this means turning the motor into a generator, converting mechanical energy into electrical energy, which can be fed back to the local network. The mechanism is extremely common in electric and hybrid vehicles where the energy is stored in the batteries and works particularly well in urban environments, where drivers tend to brake often enough to generate a lot of energy.
Lesser known applications of regenerative braking can also be found in industry. By using a regen unit in engine test stands, transmission, escalators, power plants and many other applications that use continuous braking, the braking energy of the driven system can be fed back into the network.
Regen power can be sized to the application; the capacity range can vary anywhere between 4kW and 300kW – the higher the capacity, the bigger the savings and the faster the payback. For a 90kW drive, for example, a 30kW regen unit could be suitable – because it rarely brakes at full capacity. A good regen unit should work with any AC drive and should be easy to retrofit to any inverter, irrespective of design or manufacturer, due to its non-software driven installation protocol.
RevCon can use a feed-in tariff similar to the ones found on domestic and semi-commercial wind turbines, to allow companies to charge the electricity supplier for the excess returned power, should the building not use the energy locally.
So why isn’t regen braking used in more industrial applications? Although the cost of regen units has gone down significantly over the last few years, they are still much more expensive than some of their alternatives. Like many other technologies that were ahead of their time, regenerative braking is likely to increase in popularity in the next few years.