Roaring Fork School District

Glenwood Springs, CO

EEI provided retro-commissioning services for this 76,500 SF elementary school, which was recently remodeled and expanded, but began experiencing problems related to comfort and excessive energy consumption. Systems installed in the school include rooftop VAV with displacement air distribution, a variable flow chilled water system with ice storage and a complete DDC building automation system. EEI discovered numerous issues, stemming from the replacement of the HVAC system, from design, to construction, to lack of system commissioning, to component failures.

EEI provided follow-up engineering support to design/specify corrections, assist the district in evaluation of contractor proposals and provide construction administration.

Correction of these problems was recently completed by the selected contractor and commissioned by EEI. Initial review of energy performance indicates approximately 30% operational savings for the district and a facility that finally performs up to its potential further defined as follows:

The total estimated savings potential for these measures from the perspective of CRES’s utility bill was calculated to be 109 kW peak demand savings during Xcel’s summer operation (primarily September), 125,414 kWh annual energy savings, and decreased gas energy consumption of 19,600 therms.

Annual cost savings are estimated to total $27,140 with an estimated implementation cost of $90,056 for a payback of 3.3 years. These are raw figures that do not include potential Xcel Energy recommissioning rebates other than anticipated prescriptive rebates totaling $6,400 for variable frequency drives (VFDs), which may significantly reduce implementation costs.

 
 

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