Duke University Medical Center Staff Engineer MPE design and troubleshooting Web site info : http:/eo.mc.duke.edu

Who is Green ?

 Is your toilet or faucet in your room leaking?  How long of a shower did you take this morning?

Baseline consumption data

Duke Hospital and Medical Center  Total of 250 million gallons per year  About 100 sterilizers  About 125 cold rooms with water cooled condensers  About 2500 toilets  About 200 urinals  About 900 patient beds

Baseline consumption data

Duke Hospital and Medical Center



Almost all laundry done off campus

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15,000 to 20,000 ton of HVAC cooling load

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7 million sf

100 gal per bed per day

is typical for Hospitals - Includes laundry

Baseline consumption data

Duke Hospital and Medical Center Hospital base load:  Read meters every couple of hours for 24 hours  Mid week:  60 GPM at night  225 GPM during the day!

 MSRB- Lab- 39 flushes/fixture/day

Water CONSERVATION projects

 Toilet and urinal retrofits- 1.6 GPF and green handles  .125 GPF urinals vs waterless and “special” inserts  4 to 8 times more expensive to maintain  Toilet cleaning and EVS  Shower heads- caution must be used.

 Getting hot water recirculating systems working  Recirulating water cooled condensers- 3 GPM per ton

Water CONSERVATION projects

 Cycles of concentration on cooling towers  alarms for overflow; metering- consumption greater than 0.6 gpm per ton=waste  “Camel” system for water seal vacuum pumps  saves 7 gpm costs about $20k  Economizers for sterilizers- saves ½ GPM, $2000  RO filters - tempering valve -77F-reduces waste  Post a sign in each bathroom with your number!

Water RECOVERY projects

 AHU condensate- a big one- espec. 100% OA units  Rain water recovery- maybe  RO discharge  do not use brine from pretreatment softeners but carbon and sand are okay  1 gal is wasted per gal consumed  Connect backup city water cooling systems to your condensate recovery systems- MRI, Linac, Refrigeration  Must periodically test water quality

Disaster planning

 Disaster can strike without a drought  Develop relation with local supplier  Bottle size vs 6,000 gal tanker  Planned orderly shutdowns  Cooling Towers, etc.  Split processes from potable.

 How many days before you move out?

 Where will you send the patients?

Strength in numbers

 Small changes can make a big difference  GM switches to 20W oil  takes 300k cars off the road.

 Bottled water uses a lot of resources, get reusable ones. Potable water is a small number overall.

Water conservation at HOME

 Water use at home about equal to commercial  Family of four =4,000 gallons is really good.

 Shut off main valve to house when you leave and listen for inrush when you come back

Water conservation at HOME

 Close off toilet valve overnight to check for leaks  TOTO brand very good.

 Front loader washer- 25 gal vs. 40  My family of 5 uses 3 to 5000 gal per month

War stories

 Waterless cleaners- flammable  Turning off flush valves-sleepers  Single vs dual lever faucets  42M gallons saved thus far, target is in the 70M range