Energy efficiency measures - Industrial - Manufacturing - Plastic
Template assignment
Injection moulding and light manufacturing company in Waterloo, Ontario. The plant employs 100 people including office staff. Production is 5 days per week, 16 h/d. Maintenance staff is typically working 5 h/d on the weekends.
The factory was completed in 2002, and most of the machinery was moved from their old facility. All electrical equipment has impact on the heating load. For the last 12 months, electricity consumption was 1,200 MWh and natural gas 75,000 m³. Natural gas heating at $0.40/m³, electricity at $0.10/kWh. Nearest climate data location is Guelph, Ontario.
Base case
Heating system
Building envelope
Template assignment
Injection moulding and light manufacturing company in Waterloo, Ontario. The plant employs 100 people including office staff. Production is 5 days per week, 16 h/d. Maintenance staff is typically working 5 h/d on the weekends.
The factory was completed in 2002, and most of the machinery was moved from their old facility. All electrical equipment has impact on the heating load. For the last 12 months, electricity consumption was 1,200 MWh and natural gas 75,000 m³. Natural gas heating at $0.40/m³, electricity at $0.10/kWh. Nearest climate data location is Guelph, Ontario.
Base case
Heating system
- Building is heated by natural gas
- Space heating temperature is 22 °C
- Heating change over temperature is 16 °C
- Space heating system seasonal efficiency of 75%
Building envelope
- North face of building is oriented 20° west of north
- There are no solar shading of the windows
- Building volume: 25,795 m³
- Air infiltration: 1 air change per hour
Lights
- Lighting load is 10 W/m² for 90 h/w
Computers
- 25 desktop computers are used 45 h/w
- Average computer load is 300 W
- Hot water is set at 60 °C and use is typical for an office
- Water heated by natural gas in central heating system boiler
- Hot water is available 24 h/d
- 10 injection moulding machines using 30 hp standard efficiency motors
- Operates about 8 h/d
- 75% load factor
- 10 motors used for miscellaneous manufacturing duties 10 hp standard efficiency
- Operates about 15 h/d
- 75% load factor
- Speed of all motors at full load is 1800 rpm
- Rotary screw compressor with a capacity of 125 cfm
- Compressor driven by a 30 hp energy efficient motor
- Air intake is indoor
- System pressure is 135 psig
- Average air demand is 80 cfm
- Leakage is 20 cfm
- Capacity control is on/off
- System provides compressed air for 80 of the 90 hours of weekly operation
- A medium temperature refrigeration system with seasonal COP 3 cools a manufacturing process 90 h/w
- Cooling load is 20 RT
- Duty cycle is 75%
Proposed case
Building envelope
- Introduce occupied schedule 90 h/w
- Reduce heating temperature to 20 °C, and a setback of 2 °C when the building is unoccupied
- Install a rapid closing door for the loading bay reducing the air change rate to 0.7 per hour, cost $20,000
- Install new lights in manufacturing and storage area reducing average lighting load to 8 W/m²,
- Install timers reducing usage by 10 h/w
- Cost $10,000
- Train staff to turn off computers and use the stand-by feature: estimated usage reduction of 10 h/w
- Reduce hot water supply temperature to 55 °C
- Upgrade all motors to premium efficiency units at a cost of $1,000 for each of the 30 hp motors and $500 for each of the 10 hp motors
- Decrease run time of the smaller motors by 2 h/d
- Replace existing capacity control with variable speed control
- Reduce pressure to 90 psig
- Replace indoor air intake with outdoor air
- Eliminate air leakages
- Automatic shutdown of system outside working hours (80 h/w)
- Estimate cost for efficiency measures: $10,000
- Reduction in service costs: $200 (O&M)
- Install a new refrigeration system with seasonal COP 3.5, cost $10,000
- O&M savings: $1,000 per year
- Reduce duty cycle to 60% and cut operating time by 10 h/w
Solution
The worked-out solution is the data file selected from within the RETScreen Project Database. The user automatically downloads the project database file while downloading the RETScreen software.
