Federal Reserve Bank of Boston Case Study John Yahoodik, Senior Project Manager Federal Reserve Bank of Boston Rick Dorricott, Design Services Manager.

Federal Reserve Bank of Boston Case Study

John Yahoodik, Senior Project Manager Federal Reserve Bank of Boston

Rick Dorricott, Design Services Manager Energy Investment, Inc.

Federal Reserve Bank of Boston

• Designed 1972, completed 1976

• 33 story tower; 5 story low-rise• Unique support functions• 1,130,000 square feet• Steel construction with glass &

aluminum facades• Steam heating• Electric powered chiller

cooling

Federal Reserve Bank of BostonProject Objectives

• Energy efficiency, utility cost reduction

• Facility improvement, lighting and mechanical systems

• Environmental management, CFC compliance

Federal Reserve Bank of BostonOwner’s Agent: Energy Investment,

Inc.

• Integrated energy improvement program

• Chiller replacement program– chiller specification and selection– system design– competitive bidding– construction review

Federal Reserve Bank of Boston Electric End-Use

• General office and banking– 5 am - 6 pm

weekdays – 7 am - 1 pm

weekends – some 24 hour

operation

• 24,000,000 kWh annual electricity consumption

Federal Reserve Bank of BostonElectricity Use

• Monthly electricity consumption 1992-93

• Monthly electricity demand 1992-93– relatively flat

demand

Federal Reserve Bank of BostonNatural Gas and Steam Use

• Monthly natural gas consumption 1992-93– used for cooking

• Monthly steam consumption 1990-1993– used for heating

Federal Reserve Bank of BostonOriginal Chillers

• 3 York 1200 ton chillers– 0.82 kW/ton– R-500 refrigerant– chiller 2 on in spring– chiller 3 for summer loads – chiller 1 used for backup

• 8 heat recovery chillers– 20-100 tons, 330 tons total

– R-22 refrigerant

– 0.93 - 1.48 kW/ton

– summer and winter loads

– heat recovered for hot water

Federal Reserve Bank of BostonChiller Replacement - Logistical

Issues

• Bank Security• On-going operations• Time constraints• Space constraints• Future flexibility• Facility location

Federal Reserve Bank of Boston Chiller Options Studied for CFC

Compliance

• Retrofit existing chillers for non-CFC refrigerant

• Replace with high-efficiency, non-CFC models

• Steam absorption units• Gas-fired units• District cooling

Federal Reserve Bank of Boston Criteria for Evaluating Options

• Reliability, long life• Stand-alone entity• Independent operation• Energy efficiency and performance• Life-cycle cost• Operation and maintenance

considerations• Environmentally friendly, CFC compliance

Federal Reserve Bank of BostonChiller Replacement Option Chosen

Peak MonthlyDemand Savings

Estimated Annual Savings PaybackPeriod

summer(kW)

winter(kW)

electricenergy(kWh)

electriccost ($)

maint.cost ($)

total cost($)

(years)

Replace Chillers 431.71 0.00 663,422 76,576 --- 76,576 10

• Primary chillers - 3 Carrier 1200 ton chillers– 0.56 kW/ton– R-134a refrigerant

• Heat recovery chillers - 8 Carrier

Federal Reserve Bank of BostonHVAC Improvements

Peak MonthlyDemand Savings

Estimated Annual Savings PaybackPeriod

summer(kW)

winter(kW)

electricenergy(kWh)

electriccost($)

totalcost($)

(years)

automate economizeroperation

0.00 0.00 108,158 5,431 5,431 5

convert AC-21 toreturn-air type

62.94 0.00 69,901 9,609 9,609 5

install motorizedcontrols on AC-15

0.00 4.78 139,866 7,251 7,251 1

install premiumefficiency motors

9.26 9.70 76,455 5,244 5,244 10

automate start/stopprogram

0.00 0.00 185,168 8,085 8,085 1

replace elevatortimers

0.00 0.00 381,072 16,660 16,660 < 1

install VFDs oncooling tower fans

119.40 0.00 225,652 23,480 23,480 3

Total HVAC 191.60 14.48 1,186,272 75,760 75,760 4

Federal Reserve Bank of BostonLighting Improvements

Average MonthlyDemand Savings

Estimated Annual Savings PaybackPeriod

(kW) electricenergy (kWh)

electriccost ($)

maint.cost ($)

total cost($)

(years)

LightingImprovements

662.7 3,805,897 310,822 264,600 575,422 5

• Upgraded fluorescent lighting

• Specular reflectors

• High efficiency incandescent lamps

• New LED exit kits

• Metal halide retrofit kits

• Incandescent converted to fluorescent

Federal Reserve Bank of BostonLighting Improvement Results

Federal Reserve Bank of BostonIntegrated Energy Program

• Other energy efficiency improvements help pay for chiller replacement for CFC compliance

• Shorter overall program payback period

Peak MonthlyDemand Savings

Estimated Annual Savings PaybackPeriod

summer(kW)

winter(kW)

electricenergy(kWh)

electriccost($)

maint.cost($)

total cost($)

(years)

ChillerReplacement

431.71 0.00 663,422 76,576 --- 76,576 10

HVACImprovements

191.60 14.48 1,186,272 75,760 --- 75,760 4

LightingImprovements

662.70 662.70 3,805,897 310,822 264,600 575,422 5

Total 1286.01 671.18 5,655,591 463,158 264,600 727,758 5.2

Federal Reserve Bank of BostonProject Timeline

– 8 months for engineering analysis– 18 months for project approval– 21 months to purchase, design and build

Federal Reserve Bank of BostonFive Construction Phases

• Remove chillers 2 & 3• Install & activate new

chiller 2 & refrigerant monitoring system

• Remove chiller 1• Install and activate

chillers 1 & 3• Remove heat recovery

chillers 4 & 5 and install new ones

Federal Reserve Bank of BostonProject Results

• Still under construction• Expect to save 5,300,000 kWh a year• Annual $730,000 savings• Switch to R-134a, an HFC refrigerant,

not scheduled for phaseout• Improved lighting and HVAC systems• Only a 5 year project payback period