Energy Savings
Method No 1 – Most cost effective with best overall improvement in Efficiency,
Power factor & Energy Savings
| Energy savings |
: |
8% to 45% ( Depending on application ) |
| Cost difference |
: |
Medium – Energy savings will justify payback in short period |
| Benefits |
: |
Lower starting currents, motor life extension with controlled starting,
VSD power factor correction, no mechanical switching, variable speed optimization &
control, improved torque control |
Method No 2 – Expensive yet overall most effective with the improvement in Efficiency, Power factor & Energy Savings
| Energy savings |
: |
10% to 50% ( Depending on application ) |
| Cost difference |
: |
High – Energy savings over long period will eventually justify payback |
| Benefits |
: |
Lower starting currents, motor life extension with controlled starting, VSD power factor correction, no mechanical switching, variable speed optimization & control, improved torque control |
Method No 3 – Cost effective with only motor improvement in Efficiency, Power factor contributing to some Energy Savings
| Energy savings |
: |
0% to 12% (Can be higher depending on age & sizing of motor) |
| Cost difference |
: |
-3.5% to 8% |
Method No 4 – Expensive but effective with only motor improvement in Efficiency, Power factor contributing to some Energy Savings
| Energy savings |
: |
0% to 8% |
| Cost difference |
: |
- 3.0% to 9.3% (With rebate – higher % without rebate – see below) |
This is based on Motors available on ESKOM DSM Project with rebate.
( Example : 90kW 2P with rebate = 9.1% extra motor purchase cost with only 0.74 % increase in efficiency.
90kW 2P without rebate = 18.4% extra motor purchase cost with only 0.74% increase in efficiency) |
Electric motor starters have influence on Energy Savings
General rule of thumb for various motor starters – Start up currents versus full load current
Potential savings studies ( type of load & sector ) when using
Variable Speed Drive
Potential savings studies ( type of load & sector )
1Terawatt hour = 1 million megawatt hours
EEM = Energy Efficient electric motor : VSD = Variable speed drive
Major Energy Savings on “Pump” & “Fan” applications
Studies in USA, Europe & Australia have shown that on “cubed law” loads such as pumps & fans
that energy savings of up to 50% can be achieved. (Flow control maximizes savings)
 Pumps & Fans driven by Variable Speed Drives can save up to 50% in electricity usage
 Variable Speed Drives
0.4kW up to 8000kW - 220volt up to 11000volt
Click on this address : http://www.indusquip.co.za/variable_speed_drives.htm
FREE ! ENERGY SAVINGS
CALCULATION WORKSHEET
Click on this shortcut : http://www.indusquip.co.za/pdf/WEM%20ENERGY%20SAVINGS.xls
Use Variable Speed Drives and Motors for Energy saving. |
