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“The Energy Reduction Continuum” A Process of Incremental Improvements

“The Energy Reduction Continuum” A Process of Incremental Improvements. Rock Morille, P.E., M.B.A. Vice President - Facilities Baylor College of Medicine Houston, Texas. Steam. Install Efficient Boilers to Reduce Natural Gas Usage.

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“The Energy Reduction Continuum” A Process of Incremental Improvements

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  1. “The Energy Reduction Continuum” A Process of Incremental Improvements Rock Morille, P.E., M.B.A. Vice President - Facilities Baylor College of Medicine Houston, Texas

  2. Steam

  3. Install Efficient Boilers to Reduce Natural Gas Usage Replaced 3 Cleaver-Brooks fire tube boilers in the central plant. These boilers were rated at a total natural gas input of 58.5 million BTUH and an overall efficiency of 80%. They were replaced with seven Miura low-NOx series high pressure steam boilers, having a total natural gas input 82.4 MMBTUH with an overall efficiency of 85%, yielding an immediate 5% efficiency improvement. The Miura boilers contain only one-tenth of the water of an equivalent sized fire tube boiler, and thus have the ability to ramp up to full steam production in only 5 minutes . This complete system upgrade yielded an overall 10% reduction in natural gas usage, and reduced NOx production by over 77%. The savings associated with this project continue to be over 17,500 MMBTU annually, or $140,000 per year. BCM Sustainability Initiatives - 2013

  4. Boiler Blow down - Water Heat Recovery High temperature (300 deg F) boiler blow down water is run through a heat exchanger to transfer the sensible heat stored in the 300 deg. F liquid water to the cold (70 deg. F) makeup water to the same boiler. The amount of water released (blow down) from the boiler is controlled automatically by the boiler water chemistry computer to maintain the proper amount of dissolved solids in the water inside the boiler. Solids remain in the water inside the boiler as a natural function of the evaporation process. This program works well because the ratio of make-up water to blow down (waste) water is relatively constant at 100:1. BCM Sustainability Initiatives - 2013

  5. Steam Boiler Efficiency - (20) Cycles-of-Concentration with RO Water To reduce boiler blow down requirements and related chemical usage, we first soften the water using a traditional sodium ion exchange process followed by Reverse Osmosis (RO) Water treatment to remove all impurities and suspended solids. This allows us to run a higher cycles of concentration (CoC) in the boiler, reducing blow down requirements and permitting the use of fewer scale and corrosion inhibitor chemicals. By using RO water we achieve 20 cycles of concentration vs. 8-10 cycles with only soft water. BCM Sustainability Initiatives - 2013

  6. Water

  7. Water Reuse– Clg Twr Blow down The local utility company requires that any water introduced into the sanitary sewer be cooled to less than 140 deg. F. We use the cooling tower blow down water (75 deg. F) to cool boiler blow down water (300 deg. F) and high temperature cage washer (180 deg. F) water discharge.  In the case of both the cooling tower and boilers the evaporation of water as a natural part of the process causes the amount of solids to build up in the system and a portion of this high solid water must be drained from the system to keep the chemical / solid ratio in balance. BCM Sustainability Initiatives - 2013

  8. Water Recycling – AHU Condensate Recovery This initiative began as a project to collect reject water from Reverse Osmosis water purifying systems and pump it to the cooling tower for evaporation as part of the air conditioning system.  Started in 1989 the system has been expanded (over the years) throughout the campus to collect drain water from ice machines, scientific lasers, air handling units, rain water / roof drains, and drinking fountains.  We are currently processing / recycling over 30,000,000 gallons of water a year using this system for a savings of over $140,000 per year. BCM Sustainability Initiatives - 2013

  9. Reuse Back flush Water from RO System The college produced high purity water for use by our researchers. The process of producing this water involves separating the impurities from the water and flushing them from the purification system. This flushing provides a continual stream of reject water which was historically routed to drain. We installed a system that would collect the water and pump it into the cooling towers for use as makeup for evaporation losses. These cooling towers supply water to support our air conditioning systems. In the beginning we were collecting 2 million gallons a year for a savings of $15 K per year. BCM Sustainability Initiatives - 2013

  10. Restroom Water Usage Reduction In addition to the 3.5 Gallons per Flush (GPF) we were using on our toilets, they were now offering a new product which regulated flow to 2.4 GPF. A savings of 1.1 gallons of water every time a toilet is flushed. A similar product was offered for urinal flush volume control which reduced the water per flush from our 1.5 GPF to just 1.0 GPF. A savings of 0.5 gallons each time a urinal is flushed. We replaced over 500 of these diaphragms during January and February of 2005. Our year over year water usage for the month of April, and every month going forward, was reduced by an average of 3.2 million gallons or $23,000 per month as a result of this project. The payback was just 1 month. BCM Sustainability Initiatives - 2013

  11. Electrical

  12. High Efficiency Motors Motor efficiency technology (IEEE-841) has been evolving over the last 20 years. In 2001 we stepped up our efforts to inventory every pump, air handler, and cooling tower fan motor (size, efficiency, and power factor) and evaluate opportunities to change out existing motors for the higher efficiency motors. In many cases we found that although an old motor was functioning fine, there was a huge opportunity for energy savings by replacing the old motor with a high efficiency, high power factor motor. During the years 2002 and 2003 we replaced more than 30 large (greater than 25 HP) motors with high efficiency motors. Each of these replacements had a payback of less than 18 months and a life expectancy of 7 to 10 years. Shown here is a 125-Hp exhaust fan motor. BCM Sustainability Initiatives - 2013

  13. Use VFD’s to Match Fume Air Demand; Eliminate Bypass Air Dampers Added VFD drives to control central vacuum system TSP, allowing the exhaust fans to match varying fume hood demands. Coupled with variable air volume fume hoods vs. older constant volume type, this upgrade saves energy by eliminating the need to use outside air bypass dampers to control system static pressure (vacuum). A total of 500-Hp of fans that support various exhaust systems throughout the college have been converted to VFD control. BCM Sustainability Initiatives - 2013

  14. Electrical Savings - Variable Frequency Drive Motor Controllers (VFD) We began using variable speed drives to control the speed of motors driving pumps, cooling tower fans and air conditioning fans in 1989.  Since that time we have installed these drives on over 200 pieces of equipment.  These controllers allow us to match the water or air moved through the system to the demand in a much more accurate way.  The savings derived from these units is the cubed of the speed reduction.  So a speed reduction from 100% to 80% results in an energy / cost savings of 49%.  We save over $250,000 per year using these variable speed motor controllers. BCM Sustainability Initiatives - 2013

  15. Capacitors to Improve Electrical Power Factor In large scale operations it is important that all energy delivered to a site be used efficiently as possible. The measure of power conversion efficiency within a facility is described or defined by the “Power Factor” (PF). This increases costs for power generation and infrastructure capacity (larger distribution wiring) and these costs are passed on to the customer. Low power factor facilities are also responsible for increased green house gas production when compared to facilities with higher power factors. A facility should strive to have a power factor between 0.96 and 0.99. At Baylor College of Medicine we have continually upgraded our capacitor systems to maintain a power factor of .97 or higher as our electrical load has changed over the years. BCM Sustainability Initiatives - 2013

  16. Lighting Technology – T5 Fluorescent; Motion Sensors Replace lighting systems -  In 1992 and in 2004 we changed out all the lighting system ballasts and lamps to improve the efficiency of the lighting system at BCM.  Each time the project resulted in a savings of over 1.5 million KWH per year.  Our current lighting system is more than 50% more efficient than and saves more than 3 million KWH when compared to the lighting system we had in 1990.  The savings have been over $140,000 per year. Replace Incandescent lights with fluorescent lamps - The newest florescent lamp technology is available with dimmer switch compatibility. Replace standard light switches with motion detector switches - .  Using the motion detector switches saves BCM over 195,000 KWH ($18,500) per year. Spec: Cooper Corelite T5, 2-bulb, shallow 2x4 fixture. P/n R1-WL-2N5-1-xxx BCM Sustainability Initiatives - 2013

  17. Optimize Airflow to Maintain Pressure Differentials Three exhaust fans serve the underground Vivarium area, in conjunction with three air handling units. While the AHU’s were on variable frequency drives, the exhaust fans ran at 100% speed. Their suction was regulated by dampers that bypassed outside air that caused the exhaust fans to run at a constant load. Added VFD’s to these three 125-Hp exhaust fans in order to be able to control their speed, and to match the ACH (air changes per hour) requirement of that space. With this upgrade we were able to reduce ACH from 18 to 15, yielding an immediate 70-kW power reduction, or 600,000-kWh/yr for this 24/7/365 operation. The energy savings alone was $50,000/yr (at $0.08/kWh). The capital cost of this program was 80% offset by a rebate incentive program from Centerpoint Energy. BCM Sustainability Initiatives - 2013

  18. Mechanical

  19. Replace AHU’s with Newer Units to Improve Efficiency and Reliability The new air handling units we are installing are constructed to provide the highest energy efficiency combined with the longest life of any of the equipment we have ever installed. We are using all the technologies mentioned above to minimize the energy consumption and carbon footprint of our facility. The air handling units are designed with direct drive fans which eliminates any inefficiency associated with belt slippage, variable speed drive units which match the fan speed exactly to meet the air demand at any time, and UV lights in front of the cooling coils to minimize the pressure drop across the chilled water coil, kill all organic or bacterial life forms thus improving the indoor air quality. We also utilize double wall construction to keep the air stream free of any insulation contaminates. BCM Sustainability Initiatives - 2013

  20. Power Transmission Efficiency - Replace V-Belts with Timing Belts V belt drive systems work on the principle of tangential friction allowing the energy produced by a motor to be transferred to a fan by using belts and pulleys.  In this system there is always some amount of energy lost as the belts slip as a result of the loss of tension as the belt stretches with age.  The timing belts have teeth on the inside of the belt which are used to create a positive lock between the motor pulley and the fan pulley.  The design eliminates the possibility of belt slippage. An additional benefit is long life (4-5 years) vs. less than 6-12 months for V-belts.  Makes sense in larger Hp applications (>25 Hp). Replacing the V-belt with a timing belt results in an energy savings of 4% to 6% with a payback of 8 to 14 months.  BCM Sustainability Initiatives - 2013

  21. AHU Hp Reduction – Install UV Lights to Keep Coils Clean; Destroy Organic Mat’l In 2001, in response to the indoor air quality issues we were having just after Tropical Storm Alison, we installed UV lights in every air handling unit on the campus.  The lights kill the bacteria and mold growing in the moist cool environment inside the air handling units.  A side benefit was the UV lamps also killed the bacteria growing on the cooling coils.   Recently we have started testing a new technology (Ion Bar) made by GPS Technologies. Over the past 18-months this technology has met or exceeded the UV light performance, with lower operating costs and longer life. The unit generates Hydrogen Ions that interfere with a viruses ability to reproduce. VOC reduction is also claimed, but we have not measured. The energy savings resulting from the installation of the UV lamps was roughly 5% per unit or 475,000 KWH per year ($45,125 per year). BCM Sustainability Initiatives - 2013

  22. Airflow Reduction - Lab Fume Hood Exhausts In 1994 we implemented a program to measure and adjust the air flow through our laboratory fume hoods to meet the National Institute of Health standards for the work taking place in the specific laboratory. Prior to this time, the philosophy had been to set up each hood to support the most aggressive chemicals that would potentially ever be used or simply put, to run the exhaust at the designated CFM for the highest category of activity (most dangerous work). Through this effort and working with the BCM Office of Environmental Health and the individual investigators we were able to reduce the amount of air we were exhausting by 25% over all. The beginning effort was the start of the annual lab hood exhaust testing program we now have at Baylor College of Medicine. We manage this testing (and flow adjustment) program through our Energy Management group. BCM Sustainability Initiatives - 2013

  23. Water Recycle - Kitchen Exhaust Air Scrubbers This program recycles water that was previously being disposed of after just one use. Our cafeteria uses water injected exhaust fans to minimize the amount of particulate (grease particles) and odor that is discharged from our cafeteria grilling operations. The operational process is such that the water is injected as a mist into the exhaust stream. The injected water then “captures” any particles and removes them from the air stream. This water and particle mixture then drains from the system before the air is exhausted to the outside air. The installation had the water / particle mixture routed immediately to the floor drain in the mechanical room. We installed a tank with a float controlled make up water line to create a recalculating water system. We drain this system once a week to minimize any grease buildup. This project saves over 1500 gallons of water each day or 375,000 gallons of water ($3,000) each year. BCM Sustainability Initiatives - 2013

  24. Pumping Hp Reduction - Water Pressure Control As variable speed drive units became more reliable in the early 1990’s, we began replacing the older on/off style pump control strategies with variable-speed pressure control strategies. We soon found that the technology for pressure tanks had changed to where now large rubber “bladders” maintained a separation between the air and water thus reducing the corrosive qualities of the water. These technology advances allow us to run a much smaller pump at a slower speed to maintain water pressure in the system. The result was that beginning in 1994 we started changing all our domestic water pressure control systems (pumps, pressure tanks and motor controls) to variable speed drive controlled, multi stage centrifugal pumps coupled with bladder tanks to reduce energy used to boost water pressure. Payback on these system replacements averaged 18 to 24 months including energy and labor savings. BCM Sustainability Initiatives - 2013

  25. Chilled Water

  26. Electrical Savings - Replaced Inefficient Chiller Units In 1992 we started a program to replace the two least efficient chillers (.95 KW / Ton) with state of the art chillers (.62 KW / Ton).  Each of the chillers we replaced was 800 tons in size.  The energy savings associated with replacing these two chillers amounts to 528 KW per hour or 1.5 million KWH per year (calculated running 33% of the time).  This equates to a savings of $145,000 per year. BCM Sustainability Initiatives - 2013

  27. Water Savings - Cooling Tower Filtration As part of the HVAC process, the cooling towers evaporate water to provide cooling for the air conditioning of the campus. The cooling tower system is uses direct contact between air and water to facilitate the evaporation process. As a result of the evaporation process the pure water is removed from the system and all the water and airborne solids and impurities remain in the cooling water system. This dirt accumulation in the system remains in suspension and precipitates out in the basin of the cooling towers. The cooling tower water filters save water by making sure that the cooling tower blow down water is very high in solids and it minimizes the amount of the water treatment chemicals discarded to the environment. These systems have a pay back on investment of 1 to 2 years and have a life of 10 to 15 years. BCM Sustainability Initiatives - 2013

  28. Reduced Pump and Fan Hp - Reset Condenser Water Temp based upon OAT Using variable speed drives on the cooling tower fans allows us to control the condenser water temperature to within a half of a degree F.  This accuracy allows us to reduce the condenser water supply temperature to 70 deg. F when the outside air temperature is below 60 deg. F.  The air conditioning system is designed for the condenser water supply temperature to be 85 degrees.  The savings associated with reducing the condenser water temperature is 1.5% per degree reduction.  So a 15 degree reduction equates to a 22.5% reduction in air conditioning system energy consumption.  Using this process we have reduced our energy consumption by over 2.8 million KWH per year ($270,000 annually). BCM Sustainability Initiatives - 2013

  29. Replace Cooling Tower Media to Maintain Heat Exchange Efficiency Replaced the internal labyrinth media of four (4) Marley cooling towers with new factory-provided hanging media and mist eliminators. The original media was twelve years old and beginning to show deterioration at the edges due to UV weathering and normal aging. The internals of the media was found to be clean, indicating an effective chemical treatment program. BCM Sustainability Initiatives - 2013

  30. Chiller Tonnage Reduction - Reset Chilled Water Temp based upon OAT We adjust the chilled water temperature based on the outside air temperature.  When the outside air temperature is below 50 deg. F we set the chilled water temperature at 49 deg. F.  When the outside air temperature is above 75 deg. F we set the heating hot water temperature at 44 deg. F.  BCM Sustainability Initiatives - 2013

  31. Spot Cooling - Computer Room Dedicated In 2007 we recognized that we had one data center (650 SFT) heat load which was forcing us to maintain a lower chilled water temperature in the winter than was required to satisfy the cooling requirements for all the activities taking place in the other 1.4 million SFT of the campus. The heat load from this data center was forcing us to keep the chilled water for the whole campus 2 degrees colder in the winter than would otherwise be required. The solution to this problem was to add a 7.5-ton DX, R-22, split system air conditioning system. We installed the fan coil (evaporator) in the data center and the air-cooled condenser on the Alkek Building roof. This allowed us to raise winter-month chilled water temperature for the entire campus.. The payback on this project ($20,000) was less than one winter season (4 months). BCM Sustainability Initiatives - 2013

  32. Controls

  33. Efficiency Monitoring - Energy Dashboard for Central Plant Created an “Energy Dashboard” software program to monitor real-time CHW tonnage versus energy usage compared against year-ago data. Also displayed for reference is current outdoor air data (dry bulb, wet bulb, and enthalpy). This provides the operators with some guidance on how the plant is running from an efficiency standpoint versus load. Data flows from NAE server that pulls PowerLogix data for central plant, and includes Metasys data for other parameters. Information resides in a SQL Server database. BCM Sustainability Initiatives - 2013

  34. Upgrade Chiller Controls for Efficiency / Reliability Upgraded the controls on two Trane chillers from the original “Classic Black” relay logic to the newest CH530 “AdaptiView” controls to provide more accurate process temperature control, improved chiller monitoring, and more accurate field instrumentation. This also provides continuity with controls upgrades that are offered by Trane for all new equipment. BCM Sustainability Initiatives - 2013

  35. Electrical Savings - Lights Off at Night/Weekends We utilize our energy management system to schedule hallway lighting to match occupancy. In this program, our emergency lighting systems remain on at all times to provide the life safety illumination required by NFPA, but we turn on and off our normal power light fixtures (approximately 2/3 of the total # of light fixtures) to match the hours of occupancy of the facility. In most cases this enables us to reduce lighting energy consumption between the hours of 10:00 PM and 7:30 AM weekdays (M-F and on weekends) by 2/3 of what is consumed during the occupied times. BCM Sustainability Initiatives - 2013

  36. Steam Usage Reduction - Reset Heating Hot Water Temps based upon OAT We adjust the heating hot water temperature based on the outside air temperature.  When the outside air temperature is below 38 deg. F we set the heating hot water temperature at 180 deg. F.  When the outside air temperature is above 85 deg. F we set the heating hot water temperature at 105 deg. F.  We use a linear formula to adjust the heating hot water temperature when the outside air temperature is between these two values.  By doing this we minimize our natural gas consumption and meet the needs of the building occupants.  This energy management program saves BCM over 5,000 MMBTU of natural gas consumption annually ($35,000 annually). BCM Sustainability Initiatives - 2013

  37. Other

  38. Control Valves to Balance Clg Twr Levels; Reduce Operator Fatigue Automate the 10” butterfly isolation valves below cooling towers 9 and 10 to permit automatic level control rather than labor-intensive manual control. These towers do not share a common basin with the other eight cells and their flow rate varies as condenser water manifold pressure fluctuates during heavy summer month usage. Provide 4-20mA BAS control. Reduces overflow risk and allows operators to focus on more value-added activities such as energy management. BCM Sustainability Initiatives - 2013

  39. Hurricane Rated Window Protection Film In 2004 we began the installation of “hurricane rated” window film as part of the hazard mitigation program recommended by the State of Texas’ Division of Emergency Management and the Federal Emergency Management Agency (FEMA). We selected an 8 mm thick window film with a 50% shading factor. This product is rated for sustained impacts of objects moving at 120-mph. Additionally, it provides energy savings without being so dark as to create a “cave-like” environment inside the facility. We installed over 150,000 square feet of this window film throughout the campus. The project saves a total of 7.5 million BTU’s (625 Tons) of air conditioning during the peak of summer. This equates to an electrical generation avoidance of over 413,000 kWh per year. The environmental impact of this generation avoidance is a CO2 emission reduction of over 568,000 pounds per year. BCM Sustainability Initiatives - 2013

  40. Recycling & Resource Stewardship BCM has a robust recycling program that is an integral part of the Texas Medical Center’s community-wide initiative to reduce waste and promote sustainability. 2012 Recycling Highlights Water Conserved - 27,800,00 gallons Metal Recycled - 152,878 lbs. or 76.44 tons Plastic Recycled - 14,352 lbs. or 7.18 tons Paper/Cardboard Recycled - 922,888 lbs. or 461.44 tons BCM Sustainability Initiatives - 2013

  41. Demand Response – Electrical Energy Load Shed Rebates We have elected to participate in a Centerpoint power company initiative whereby we agree to load shed our power usage during periods of peak power demand in order to allow the power company to meet all critical loads without interruption. For 2013 we have elected to put 3.8-MW of power on this program. (summer) We are able to take advantage of this program by using our diesel powered backup systems to drive our largest 2,500-ton chillers. This saves BCM over $225,000 per year. Shown here is one of two 2.5-MW Cummins diesel generators. BCM Sustainability Initiatives - 2013

  42. Q & A

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