Marriott Corporate Headquarters John Henderson Marriott Corporation Marriott

Marriott Corporate Headquarters John Henderson Marriott Corporation

Marriott Headquarters • 1977 construction of ~700, 000 square feet • 1986 addition of ~300, 000 square feet • 8 floors including basement • Office space operates 7 am to 6: 30 pm • Many areas at ~10% operation 24 hours a day, 7 days a week

Marriott Headquarters HVAC & Lighting Equipment in 1989 • One 900 ton & one 750 ton electric centrifugal – R-11 refrigerant, 0. 86 & 0. 92 k. W/ton efficiencies – installed in 1977 with original building construction • • Two 450 ton chillers, 0. 62 k. W/ton, R-11, circa 1986 Two 1000 ton cooling towers Two 350 horsepower gas boilers, 175°F hot water ~12, 000 fluorescent fixtures, two 40 watt U-tubes each ~1800 assorted incandescent lamps & spots

Marriott Headquarters Project Scenario • Virtually no maintenance since 1977 • Half of plant didn’t work • Parts leaked, made noise • Not meeting safety requirements • Not providing building comfort boiler room

Marriott Headquarters “Before” Pictures air handler unit sample motor

Marriott Headquarters Project Challenges • • • Everything needed attention at once Large budget for the wrong things Set strenuous daily goals Conserved energy wherever possible Considered many new systems Most work and analysis done in-house

Marriott Headquarters System Solutions • Short term, through 1994 – cleaned up boiler room – rehabbed equipment - motors, boilers, piping, air handlers, etc. – converted all chillers to R-123 – increased cooling tower capacities to 1200 tons – added heat exchanger for free cooling – put electronic ballasts in lighting fixtures

Marriott Headquarters System Solutions • Long term, 1994 until today – two new traditional chillers, an ice chiller and a gas/oil absorber – redesigned chilled water piping for more effective primary/secondary loops – added window films – extensive rebalancing of air handlers – new motors added – new control system added

Marriott Headquarters Variety of New Chillers • One 670 ton electric centrifugal chiller – replaced 900 ton chiller – 0. 53 k. W/ton efficiency, R-123 refrigerant • One 530 ton combination gas/oil-fueled absorber – replaces 750 ton chiller, used for peak shaving

Marriott Headquarters Variety of New Chillers • One ice chiller and storage system – converted from 450 ton chiller – 2400 tons of ice, or 350 tons of regular cooling, 0. 68 k. W/ton efficiency, R-123 refrigerant ice chiller ice tank • One 400 ton electric centrifugal chiller – replaced 450 ton chiller – 0. 53 k. W/ton efficiency, R-123 refrigerant • Total of 1950 tons of total cooling capacity, versus 2550 tons previously

Marriott Headquarters Free Cooling • Condenser water from cooling towers can bypass the chillers • Cooling towers have variable frequency drives • Up to 500 tons of cooling provided • Used during mild weather in spring and fall

Marriott Headquarters Cooling Load Reductions • Replaced magnetic ballasts of fluorescent lighting with electronic ballasts • Added tinted films to windows - block sunlight to reduce solar heat gain • Complete balancing of air distribution system, including exhaust system • Energy. Star printers - used sleep mode to reduce energy use

Marriott Headquarters Cooling System Improvements • Just finished adding new motors to air handlers - efficiency improved from 87 -89% to 94 -95% • New EMS system - Andover 1986 model combined with 1994 model - computerized control, and help deciding what systems to run when

Marriott Headquarters Project Timeline • New facility management in 1989 • Plant clean-up began right away and took 18 months • Plant retrofit work began in 1991 • Lighting work in 1992 • Window work & AHU balancing in 1994 • New chillers installed in 1994 – 1 year of construction • New AHU motors added in 1998

Marriott Headquarters Financing Structure • Won 1 st place ENCOMP award in 1992 for large buildings - got us noticed • $1 million from Maryland Public Service Commission through Washington Gas – paid for gas absorber • $1 million rebate from Pepco – replaced one chiller, lighting retrofits, added window films • Sold one 450 ton R-123 chiller • Saved money by using in-house labor • Used almost no cash to finance the project

Marriott Headquarters “After” Pictures boiler room today color coded piping

Marriott Headquarters Project Results • Safe, clean, highly efficient plant • Remarkable system innovation & flexibility • Reduced peak cooling capacity • Much improved tenant/building comfort • No longer using CFC refrigerants – first CFC conversion to R-123 • Saving 1. 8 MWhrs of electricity per year