The Colombian company West Arco, which is part of ESAB Group, the world's largest producer of welding and cutting equipment, has been executing a modernization plan for its plant in Bogota since 2017. Among the actions taken, one of them was the replacement of the old electric motors driving its equipment for WEG high efficiency solutions. Aiming at implementing its processes and products in line with sustainability principles, West Arco found at the WEG solutions high potential for energy saving. Besides reducing energy consumption, the Colombian company intends to minimize the environmental impacts on its production processes.

In the current phase of factory modernization, a total of 11 electric motors have been replaced. Topics considered for the replacement included equipment that had between 2000 and 5000 hours of operation per year, the size of electric motors in relation to the application requirements, electric motors in service for over 10 years and those that were rewound more than twice.

 The equipment selected for which the electric motors were replaced are included in this table:

 

Driven machine

Motor output power(HP)

Efficiency level installed

Oven

100

High

Press 4

40

Premium

30

Premium

Press 3

40

Premium

30

Premium

(1)Press 1

30

Premium

25

Premium

Wire Drawing Machine

60

Premium

50

Premium

50

Premium

50

Premium

(1) Application redesigned.

The evaluation of the results was carried out in association with the Colombian Energy Efficiency Council considering the measurements in the old electric motors (before the replacement) and after the installation of the WEG motors. In some applications, the prior analysis of the consumption and performance of the standard motors was based on historical measurements of the maintenance area, simulating the operation of the old motors at the measured conditions of the new motors. The average active power and the load percentage to guarantee the analysis in very similar conditions of the load operation cycle on the application was also considered. The stand-by period of the equipment was not considered on this analysis.

With this analysis the following results were achieved:

 

Driven machine

Consumption (kWh-year) old motors

Consumption (kWh-year) New WEG motors

Saving

kWh-year

%

Oven

102.216,33

98.037,68

4.178,66

4.1%

Press 4

41.818,85

39.269,18

2.549,66

6.1%

Press 3

36.957,70

34.886,04

2.071,66

5.6%

Press 1

52.766,80

49.963,31

2.803,49

5.3%

Wire Draeing Machine

182.360,79

171.253,43

11.107,37

6.1%

Total

416.120,47

393.409,64

22.710,84

5.4%

Benefits:

Financial saving: Taking into account the drop in consumption of 22,710.84 kWh, in the amount of COP $ 340,00 per kWh (West Arco contract), the annual saving for the company is COP $ 15.4 million. Therefore, the investment payback is achieved within approximately 4.8 years.

Environmental benefit: The reduction of indirect CO2 emissions due to reduced consumption is 64.5 tCO2, using a UPME factor of 0.367 tCO2 / MWh.