Nearly every production facility and each job in commercial and industrial fields depends on electrical drives, even if it is only the ventilation drive in the PC. In manufacturing, nearly two thirds of electric power is used for electric drives, and with increasing automation the use of electric drives will continue to rise.

Potential

Measurements and studies show that electric motors have a power saving potential of up to 40%. However, experience also shows that this significant potential often remains unused by companies, and so they sacrifice a possible reduction in operating costs. Investments into energy-efficient electric drives often amortize already in less than one year. With the use of high-efficiency electric motors, optimized as a function of the operation hours, as well as the consistent use of frequency rectifiers for electronic speed regulation, you can clearly reduce power consumption.

Measures/Steps, improvements

The following measures promise the greatest savings:

• Replacement of oversized drives (a constant lower cos phi is a clear indication of oversize)
• Use of high-efficiency motors (e.g. use of energy saving motors and 4-pole low-voltage three-phase motors)
• Speed regulation of motors with significantly changing loads (e.g. use of frequency rectifiers for chain conveyors)
• Meeting demand by switching off and on of motors and improvement of the operational reaction current compensation

Assessment and evaluation

The first step toward optimizing the drive system is an inventory of the drive system components and their functionality. This should cover the following points:

• description of the basic system
• documentation and measurement of system operation parameters
• global indicators of system performance

Based on the inventory, an evaluation of all energy-saving technical measures is necessary.

The current consumption of motor systems is determined by

• engine efficiency
• sizing
• regulation
• quality of power supply
• mechanical translation system
• maintenance practices
• efficiency of the peripheral equipment

To exhaust the savings potential, all components of a motor system must be optimized, whereby the applicability of certain measures and the cost reduction potential depend on the size and specific situation of the company. Only an evaluation of the system and of the needs of the enterprise can help to determine which measures are both applicable and profitable. Support with the analysis is available with an energy service provider.

Source: Austrian Chamber of Commerce