# Presentation: 270974

## Auraria Higher Education CenterCase Study

**John Ismert & Frank Ellis**
- Auraria Higher Education Center
- Facilities Management

## Auraria Higher Education Center

**Built in 1976-77**
**18 campus buildings**
**1,700,000 square feet of office and classroom space**

## Auraria Higher Education CenterProject Scenario

**Campus built 20 years ago**
**Fast-track construction project**
**All the equipment is beginning to wear out at once**
**Energy efficient systems have progressed a lot in 20 years**
**Time for some major retrofit work**

## Auraria Higher Education CenterMain Cooling Plants

**North Classroom Chiller Plant**
**P.E. Building Chiller Plant**
**Plaza Building Chiller Plant**
**North Chiller Plant**
**serves Science, Arts and Library buildings**
**South Chiller Plant**
**serves Central, West, South, and Technology buildings**

## Auraria Higher Education CenterHeating & Hot Water System

**Purchased steam from Public Service Company in Denver for heating**
**Hot water generated from heat exchange with steam system**
**Typical of late 1970s with escalating gas prices**
**Studied replacement options but decided to keep steam system**
**would have needed 60+ gas boilers**
**able to negotiate lower steam cost**

## Auraria Higher Education CenterElectricity Use in North Chiller Plant

**Monthly cooling and non-cooling electricity consumption 1995**
**Monthly electricity demand 1995**

## Auraria Higher Education CenterProject Challenges

**More work than can be done under the budget available**
**Must fit into a 10 year self-funded project**
**Coordination of systems between all campus buildings**
**Need to restore cooling capabilities before the summer of 1997**

## Auraria Higher Education Center Campus Improvements Made

**New efficient chillers and cooling tower in North Chiller Plant**
**New direct digital controls in 7 buildings **
**Air side improvements in many buildings**
**Lighting improvements**
**Fume hood efficiency improvements**

##  Auraria Higher Education CenterNorth Chiller Plant

**Original Chillers**
**Two 550 ton centrifugal electric chillers**
**R-12 refrigerant (CFC)**
**0.78 kW/ton efficiency**
**New Chillers**
**Two 550 ton centrifugal electric chillers**
**R-134a refrigerant (HFC)**
**0.48 kW/ton efficiency**
**Undersized cooling tower replaced**
**single-cell, induced draft tower**

## Auraria Higher Education CenterNorth Chiller Plant Energy Savings

## Auraria Higher Education Center Direct Digital Controls

**Added to 7 campus buildings**
**New fiber optic network**
**More aggressive energy conservation strategies**
**tighten chilled water and hot water resets**
**tighter run times**
**changed evaporative cooling & chilled water sequencing**
**Monitored water meters for sprinklers & cooling towers for more accurate sewer credit**

## Auraria Higher Education CenterAir Side Improvements

**Science building**
**2 new air handling units **
**new coils on 4 old air handling units**
**new VFD drives and motors for supply air fans**
**replaced variable air volume boxes**
**Art building**
**replaced evaporative cooler media**
**PE building**
**failing heat storage wheel replaced with heat exchanger**

## Auraria Higher Education CenterLighting Improvements

**High efficiency T-8 lamps**
**Rapid start electronic ballasts**
**Compact fluoruescents in place of incandescents**
**Exit lamps replaced with long life lamps**
**10,682 fixtures modified in 13 buildings**
**Light levels maintained or improved**

## Auraria Higher Education CenterFume Hood Improvements

**Over 50 fume hoods retrofitted**
**North Classroom and Science buildings**
**Proximity sensors installed and attached to 2-position dampers**
**reduce air flow from 100 fpm to 60 fpm at night or when no one is near the hoods**
**Integrated operation of building make-up and exhaust air and fume hood ventilation**

## Auraria Higher Education CenterEstimated Project Finances

**Other improvements help pay for chiller plant work**

## Auraria Higher Education CenterFinancing Structure of Project

**Ten year bond from AHEC**
**$2 million worth of improvements**
**$175,000 demand side management rebates**
**$40,000 ICP grant, $35,000 R-12 credit**
**Annual utility savings of ~ $300,000**
**7.2 year overall project payback period with performance contracting service provided**

## Auraria Higher Education CenterProject Timeline

## Auraria Higher Education CenterProject Results

**Utility savings of about $300,000 annually**
**Took advantage of DSM rebate programs**
**More comfortable learning environment**
**Increased energy awareness level at AHEC**
**Newer, more efficient state-of-the-art systems**
**Reduced dependence on CFC’s **