Portable Classroom Controls Project

1
Portable Classroom Controls Project

• Chuck Collins
• RCM Meeting
• April 27, 2007

2
The portable classroom
Time clock User control Electric heating No
scheduling capability Electric heat pumps No
A/C Exhaust fans Limited windows No demand
charges
3
Part of PSE rebate program for schools

• List of eligible equipment
• Variable rebate amounts depending on which pieces
  of equipment installed
• Application for rebate
• Rebate amount is close to cost of controller

4
Portable classroom control project process

• Project research (cost/benefits, other data)
• Make pitch to organization
• Rebate application, work with PSE early
• Find a contractor to do the work
• Commence with project
• Set up temperature set-points, times, etc
• Verify avoided costs, consumption
• Receive rebate

5
The Project

• 127 portable classrooms
• Upgraded thermostat controller
• Connected to District DDC through network
• Control setpoints via DDC system
• Can verify temps, setpoints, trends, etc
• Ability to remotely shut down all portables
• Scheduling, snow day, etc

6
After-project analysis using PSEs EIS
March 2005 through February 2007
7
Weekly analysis shows weekend shutdown
Feb 24, 2007 through April 24, 2007
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Daily profile 2005 High peak, runs during night
hours
First week of March, 2005
9
Daily profile 2006 Systems running 24/7
First week of March, 2007
10
Daily profile shows lower demand, lower night
consumption
First week of March, 2007
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Avoided electricity calculations

• Mar 2005
• Cost - 75.22
• kWh 942.26
• Mar 2006
• Cost - 182.72
• kWh 2,391.50
• Mar 2007
• Cost - 62.97
• kWh 766.45

942.26 2391.50 2 1,666.9 766.45
900 kWh per year or 54
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Avoided cost calculations

• Mar 2005
• Cost - 75.22
• kWh 942.26
• Mar 2006
• Cost - 182.72
• kWh 2,391.50
• Mar 2007
• Cost - 62.97
• kWh 766.45

75.22 182.72 2 128.97 - 62.97
66.00 per year or 51!
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Avoided cost survey

• 18 portables at various sites (14 of total)
• Used PSEs Energy Interval Service for data
• Total electricity cost March 2006 2,468.39
• Total electricity cost March 2007 1,854.49
• Avoided monthly cost for sample 613.90
• x 10 months 6,139.00 annual avoided cost
• / 18 portables 341.05 per portable, per year
• x 127 portables 43,314.05 (estimated annual
  avoided cost, based on survey)

14
Total cost/benefit

• Estimated annual savings 43,314
• Total project cost 110,642
• Simple payback (no rebate) 2.6 years
• PSE rebate 29,750
• Actual project cost 110,642 - 29,750 80,892
• Simple payback (with rebate) 1.9 years

15

• Thank you!!
• Questions??