Minimizing Efficiency Loss Caused by Motor Rewinds

Abstract

It is estimated that rewind efficiency reductions for induction motors up to 250 kW cause annual energy losses in Europe of between 1500 and 2000 GWh/annum. This represents an increased energy cost to European Industry of up to 13 5M Euro/annum.

Work done in the USA and later in the UK shows that much of the technology already exists to reduce rewind losses almost to zero. This work has been reviewed and extended in a recent EU ‘SAVE’ Project (yet to be published) entitled “Barriers Against Energy Efficient Motor Repair”.

The fragmented nature of the European Repair Industry (most repairers are SME’s, some very small) coupled with a lack of awareness of any problem by motor users are considered the main barriers to improvement. It is recommended that simple qualification schemes for repairers be introduced which would include customer awareness, training and third party accreditation elements; also that some funding be allocated from future carbon tax revenues to set up such schemes.

Because motor repair is an essentially local industry the exact requirements in different countries may differ. However, it is recommended that a scheme being introduced by the UK Repair Trade Association (the AEMT) with help from the UK Government be monitored carefully and if successful be used as a model for other schemes elsewhere in the future.