Calculation
| Summary | - A freed large-press hour is worth $55 once an order fills it, and we count 70 percent as filled.
- At 300 hours per year, that is about $11,600.
- Those hours use 3,000 kWh less in a smaller press, about $300.
- The scheduler's weekly check costs about $3,000 per year, which leaves about $8,900.
|
| Large-press hours freed, once orders fill them | 300 hours x $55 x 70 percent filled = $11,550 |
| Electricity saved per year, in kWh | 300 hours x 10 kW = 3,000 |
| What that electricity costs | 3,000 kWh x 10 cents per kWh = $300 |
| Less the scheduler's weekly check | 1.5 hours per week x 50 weeks x $40 per hour = $3,000 |
| What fixing it could save per year | $11,550 + $300 - $3,000 = $8,850 |
Not counted
- The freed hours that no order fills are not counted: 30 percent of them.
- Wear on a small mold from more clamping force than it needs is not counted.
- Plastic spoiled by waiting hot in a large barrel between small shots is not counted.
- Orders that ship on time because a large press was there for them are not counted beyond the press hour itself.
Illustrative sample. The plant, the walk and the footage are synthetic.