Posted to News on 14th Jul 2010, 00:00
Turn fans down to reduce emissions
If just half of Britain's electric motors were reduced in speed by 10%, it would have the net effect of mitigating for the carbon emissions of 9.8 million cars every year. While this fact might not enthuse Jeremy Clarkson, it has a far more serious message and that is that governments subscribing to the Kyoto Protocol, and its greenhouse gas emissions reduction targets, continue to ignore the low hanging fruit that electric motor control presents.
According to GAMBICA, the UK's body representing the automation and control manufacturers, the simple control of electric motors has been overlooked as a significant energy conservation measure. While energy efficiency attention has tended to focus on building fabric, lighting and heating, motors have been largely ignored. By doing as GAMBICA suggests and controlling motors, a populace equivalent to nearly four million households would be rendered carbon neutral - at an average of 6.5 tonnes of emissions per household.
Similarly, long term consideration is given to reducing car exhaust emissions by both vehicle design and discouraging car use, yet the expedient of controlling electric motors in buildings and industry will achieve a greater net effect in the short term.
Likewise in electricity generation, where exploration of renewable and green energy continues apace while controlling electric motors would save the entire output of Drax, the UK's largest coal fired power station, every year. The reason the savings are so great, explains Steve Brambley of GAMBICA, is that electric motors consume huge amounts of electricity - about two-thirds of industrial energy use and about one quarter of total UK consumption. A simple electric motor costing a few hundreds of pounds can be expected to consume many tens of thousands of pounds worth of electricity over its useful lifetime.
The laws of physics concerning fans means that for every 10% reduction in speed, in accordance with the cube law of fans, there is subsequent saving of three times that in electricity consumed.
