# Presentation: 710393

## Charles F. Hurley BuildingCase Study

**B.J. Mohammadipour**
**Bureau of State Office Buildings**

## Hurley Building

**Built in 1971**
**Poured concrete construction**
**Department of Employment and Training & Group Insurance Commission**
**6 floors office plus 2 level parking garage**
**340,000 square feet office, 15,000 square feet computer**

## Hurley Building Original HVAC Equipment

**Steam absorption cooling plant generating chilled water for cooling**
**Raw steam for building heating**
**Electric powered DX units to cool the computer room, containing CFCs**
**Steam powered water heater**
**Pneumatic controls with minimum automation**

## Hurley Building Heating and Cooling Steam Use

**Hurley Building ****Heating and Cooling Steam Use**

## Hurley Building Electricity Use

**Monthly electricity consumption    1991-92**
**Monthly electricity demand 1991-92**

## Hurley Building Project Scenario

**Catastrophic failure of absorption cooling plant in 1992**
**Rising cost of steam/water, ~20% increase from 1989 to 1992**
**Expensive maintenance contract for systems**
**Computer room cooling units at end of life**

## Hurley Building Project Challenges

**Need to restore cooling capabilities before the summer of 1993**
**office space cooling**
**computer room cooling**
**Fuel switch **
**from steam to natural gas or electricity**
**must also replace heating and hot water systems**
**Space, weight and routing constraints of 6th floor mechanical room **

## Hurley Building  System Solution

**Gas fired chiller/heaters installed **
**Computer room cooling tied into chiller/heater**
**Domestic hot water fueled with natural gas**
**Energy Management System installed**
**Lighting improvements coincident with project**
**New maintenance contract**

##  Hurley Building  Chiller/Heater

**Chiller/heaters installed for main cooling and heating**
**2 York 600 ton absorption chiller/heaters**
**natural gas fired **
**require hydronic coils to allow air handling units to use hot water instead of steam**

## Hurley Building  Other HVAC Systems Changes

**Water heating**
**kitchen and lavatory hot water supply**
**converted from steam to natural gas fueled**
**Computer room cooling**
**single DX chiller used for wintertime cooling**
**tied to chiller/heater to meet summer loads**

## Hurley Building Lighting Improvements

**Lighting improvements made in 1992**
**new reflectors, lamps and ballasts**
**light levels maintained or improved**
**Funded by Boston Edison Company**
**Implemented in Hurley building and 3 other buildings coincidentally with HVAC project**
**Savings for all 4 buildings**
**4.86 million kWh peak, 1.82 million kWh off-peak**
**1.7 MW demand reduction**
**$580,000 annually**

## Hurley Building  New Maintenance Contract

**Renegotiated scope of maintenance contract**
**replaced failing absorption chiller**
**replaced computer room DX units with chilled water coils and one electric chiller**
**eliminated most pneumatic controls**
**Additional maintenance contract for new absorption chiller/heaters**
**Total maintenance costs reduced by at least $126K annually**

## Hurley Building Integrated Energy Program

**Lighting improvements and new maintenance contract help pay for HVAC system changes**

## Hurley BuildingFinancing Structure

**Chiller/heater cost**
**$565,000 purchase cost paid up front**
**$472,000 installation costs financed over 3 years**
**$50,000 rebate from Boston Gas**
**Computer room, water heater, EMS system, hydronic coils financed over 3 years**
**Lighting improvements funded by Boston Edison Company in 1992**

## Hurley Building Project Timeline

## Hurley Building Operating Cost Changes

**Gas replaces steam for cooling**
**Maintenance costs reduced**

## Hurley Building Project Results

**Chiller/heaters fit into mechanical room**
**Utility savings of ~ $300,000 annually**
**Maintenance savings of ~ $140,000 annually**
**Replacement of steam with natural gas**
**Improved building comfort from better balancing and EMS system controls**
**$420,000 increased operating cost revenues by finding occupancy rate to be 88% not 64%**