Minnesota’s Public Building Enhanced Energy Efficiency Program

Mark Hancock, P.E. — Jan 2014


Project Background

In September 2009 the State of Minnesota allocated federal stimulus funds and contracted with the Center for Energy and Environment to administer an existing building commissioning program for public buildings.

All government-owned buildings over 100,000 square feet were considered for the program. This included all buildings at Minnesota State Colleges and Universities, the Department of Administration, and the Department of Corrections. This program was designed to help the state achieve its energy conservation goals while answering two key questions about building commissioning:

  1. What percentage of the state’s total building population could be cost-effectively served?
  2. What energy savings could be expected from such an effort?

The State of Minnesota’s Public Buildings Enhanced Energy Efficiency Program (PBEEEP) ran from 2009 through 2014. Modeled after similar utility programs, PBEEEP sought to transform Minnesota’s building commissioning market from disparate, provider-controlled approaches to systematic approaches aligned with industry best practices.

Investigation

PBEEEP’s distinctive features were:

  • High level of participation reached 75% of candidate buildings.
  • Thorough energy investigations stretched over 6-9 months to include both heating and cooling seasons.
  • Limited to state government-owned buildings.
  • Funded independently of any utility company.
  • Recommissioning providers brought a wide range of prior experience.

Program applicants represented 374 buildings totaling more than 31 million square-feet in 71 sites statewide. PBEEEP completed full studies at 43 sites totaling 15 million square feet. The average study performed by recommissioning providers on the State of Minnesota’s Master Roster cost $62,000 for an average square-footage of 370,000. 

CEE determined that at least 526 buildings totaling 13 million square feet were not suitable for further investigative effort because it wouldn't be cost effective due to already low energy use or recent major upgrades. These preemptive determinations were completed for a nominal cost of $2,500 per screening.

Improvements

The table below summarizes savings measures identified through PBEEEP. These measures account for 79% of the total savings identified.

 
Number
 
 Finding Type
Payback (years) Site energy savings (kBtu/ft2yr)
135 Time of day enabling is excessive 1.1 3.3
97 Economizer operation not optimal 4.4 2.0
88 Excess enabling of equipment 0.7 2.1
88 Retrofit - Efficient Lighting 8.2 1.2
44 Zone setup/setback 0.9 2.6
23 Other controls 11.3 3.1
21 Lighting on more hours than necessary 4.7 1.1
21 Other retrofit (mostly faucet aerators) 1.9 0.8
17 Deferred maintenance 2.9 1.2
14 Leaky/stuck valve 1.9 3.9
116 All others 6.7 1.7
664 Total 3.9 2.1



Program Highlights

  • Commissioning can save at least 4% in large buildings.
  • Savings depend on building-specific factors such as operator training, operating hours, and occupancy rates.
  • Recommissioning projects tend to benefit from independent quality control.
  • Among those managing the various commissioning projects, ongoing deep engagement led to greater energy savings.
  • Benchmarking alone cannot fully predict savings potential; site visits are needed.

 

Project Info


PBEEEP_Grey-(2).png

Timeline

2009-2014

Annual Implemented Savings
 
  • Electricity: 17,898,759 kilowatt-hours worth $879,746
  • Peak demand: 1,051 kilowatts worth $21,228
  • Natural gas: 781,878 therms worth $489,986
  • Steam: 9,112 MMBtu worth $169,488
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Program Results from the State of Minnesota's PBEEEP