Tim Facius Baltimore Aircoil

Transcription

1 Presented By: Tim Facius Baltimore Aircoil Slide No.: 1

2 CTI Mission Statement To advocate and promote the use of environmentally responsible Evaporative Heat Transfer Systems (EHTS) for the benefit of the public by encouraging: Education Research Standards Development and Verification Government Relations Technical Information Exchange Slide No.: 2

3 CTI Objectives Maintain and expand a broad base membership of individuals and organizations interested in Evaporative Heat Transfer Systems (EHTS). Owner/Operators Manufacturers Suppliers Identify and address emerging and evolving issues concerning EHTS. Encourage and support educational programs in various formats to enhance the capabilities and competence of the industry to realize the maximum benefit of EHTS. Slide No.: 3

4 CTI Objectives Encourage and support cooperative research to improve EHTS technology and efficiency for the long-term benefit of the environment. Assure acceptable minimum quality levels and performance of EHTS and their components by establishing standard specifications, guidelines, and certification programs. Establish standard testing and performance analysis systems and procedures for EHTS. Communicate with and influence governmental entities regarding the environmentally responsible technologies, benefits, and issues associated with EHTS. Encourage and support forums and methods for exchanging technical information on EHTS. Slide No.: 4

5 STD-201 CTI Certification Program The standard sets forth a program whereby the Cooling Technology Institute will certify that all models of a line of evaporative heat rejection equipment offered for sale by a specific Manufacturer will perform thermally in accordance with the Manufacturer s published ratings. Applies to Mechanical Draft Evaporative Heat Rejection Equipment such as Cooling Towers, Closed Circuit Coolers (and Evaporative Refrigerant Condensers). Slide No.: 5

6 Please visit our website at Slide No.: 6

7 Publication and Presentation Disclaimer 2011 The information contained in the following publication, paper or presentation is intended for education by the author or presenter, however information given is in no way an endorsement of the Cooling Technology Institute. The publication, paper or presentation has been reviewed by the CTI staff and program committee for commercial content, however there may be differing opinions regarding the content of information. The Cooling Technology Institute accepts no liability for its content. Slide No.: 7

8 Benefits of Water Cooled vs Air Cooled Equipment for Air-Conditioning Applications Slide No.: 8

9 Overview Climate Change Background US Response Climate Change and HVAC Benefits of Water Cooled Equipment Water Usage Energy Savings Tips EPA Others Slide No.: 9

10 U.S. Government commitment to reduce greenhouse gas emissions can have a significant impact on HVAC system design. Slide No.: 10

11 Definition Global Warming Global warming is the average increase in the temperature of the atmosphere near the Earth's surface and in the troposphere, which can contribute to changes in global climate patterns. Slide No.: 11

12 Definition Global Warming Global warming can occur from a variety of causes, both natural and human induced. In common usage, "global warming" often refers to the warming that can occur as a result of increased emissions of greenhouse gases from human activities. Slide No.: 12

13 U.S. Commitment Reduce Global Warming For decades it has been clear that the way Americans produce and consume energy is not sustainable. Our addiction to foreign oil and fossil fuels puts our economy, our national security, and our environment at risk. Slide No.: 13

14 U.S. Commitment Reduce Global Warming The Recovery Act was signed into law on February 17, 2009 and has invested $80M in the clean energy economy. Development of renewable energy and clean technologies Smart electric grid and energy efficient homes, offices, and appliances High speed rail and advanced car batteries Slide No.: 14

15 U.S. Commitment Reduce Global Warming Leadership in Sustainability President Obama signed an Executive Order on Federal Sustainability, committing the Federal Government to lead by example and reduce greenhouse gas emissions by 28% by 2020, increase energy efficiency, and reduce fleet petroleum consumption. Slide No.: 15

16 U.S. Commitment Reduce Global Warming Monitoring Emissions For the first time, the U.S. will catalogue greenhouse gas emissions from large emission sources an important initial step toward measurable and transparent reductions. Slide No.: 16

17 Global Warming Greenhouse gasses include: Carbon Dioxide (CO 2 ) Methane (CH 4 ) Nitrous Acid (N 2 0) Hydrofluorocarbons (HFC s) Perflurocarbons (PFC s) Sulfur Hexafluorides (SF 4 ) Slide No.: 17

18 U.S. Greenhouse Gas Emissions by Component, 2001 Slide No.: 18

19 U.S. Greenhouse Gas Emissions Carbon Dioxide (CO 2 ) emissions account for approximately 85% of the U.S. greenhouse gas emissions. Transportation Heavy Industry Utilities Slide No.: 19

20 Major CO 2 Emission Sources Utility Industry Fossil Fuel Burning Power Plants Produce 55% of U.S. electricity Addition of exhaust gas scrubbers not economically viable for most plants Only 35% of Power Plants have exhaust scrubbers. Rather than upgrade the power plants, decision is to phase-out many of them. Slide No.: 20

21 U.S. Government Plan to Reduce CO 2 Emissions from Power Plants Convert to less carbon intensive fuels or noncarbon fuels Taxation of carbon fuels Regulation of emissions for new plants More research and funding for renewable energy Reduce energy demand New energy-saving technologies Improve efficiency of equipment and systems Slide No.: 21

22 Electricity and Air Conditioning About one-sixth of all the electricity generated in the U.S. is used to air-condition buildings. Air-conditioning systems drive many power plant peak loads and have been identified as an energy reduction opportunity. Slide No.: 22

23 Basic Air-Conditioning System Large Buildings (> 300 tons) Water cooled systems provide clear-cut economic and environmental justification. Mid-size Buildings ( tons) Air cooled systems may offer first cost incentive to sacrifice energy efficiencies of water cooled systems. Slide No.: 23

24 Cooling Tower AHU - 1 AHU - 2 Pump AHU - 3 Condenser Pump Evaporator Slide No.: 24

25 Benefits of Water Cooled Systems Water-cooled systems More energy-efficient than air-cooled systems approximately 35% Reduced plan area Reduced sound Independently certified performance AHRI for chillers CTI for cooling towers Slide No.: 25

26 Challenges of Water Cooled Systems Water-cooled systems Higher installation cost Water use Consider the water use at the cooling tower Consider the water used at power plant to create energy Water treatment Slide No.: 26

27 Water Usage Water cooled systems recycle 95% of the total water. The remaining 5% is lost to evaporation & bleed. NO water is destroyed. A small portion of the water is bled from the system to control the build-up of impurities. Bleed Rate = Evaporation Rate Cycles of Concentration -1 Water use is proportional to load and time of day. Trend toward using grey water for make up. Slide No.: 27

28 Water Quality and Control Cost Considerations Water-cooled systems require treatment to control scale/corrosion and biological growths. Chemical or NCD Water and chemical costs must be included in a cost analysis of water-cooled and air-cooled systems. Slide No.: 28

29 Cooling Tower Industry Answer Hybrid technology Optimizes water use and energy use based on load, water availability Materials of Construction Increase cycles of concentration Use grey water Slide No.: 29

30 Optimize Energy and Water Costs Market trends suggest that the demand for energy resources will rise dramatically over the next 25 years: Global demand for all energy sources is forecast to grow by 57% over the next 25 years. U.S. demand for all types of energy is expected to increase by 31% within 25 years. By 2030, 56% of the world s energy use will be in Asia. Electricity demand in the U.S. will grow by at least 40% by Sources: Annual Energy Outlook (DOE/EIA-0383(2007)), International Energy Outlook 2007 (DOE/EIA-0484(2007), Inventory of U.S. Greenhouse Gas Emissions and Sinks: (April 2007) (EPA 430-R ) Slide No.: 30

31 U.S. Actions Impacting HVAC Systems and Equipment ASHRAE Standard 90.1 as basis for energy efficiency for commercial buildings New ASHRAE Standard 189 California Title 24 Slide No.: 31

32 ASHRAE Standard 90.1 Basis of energy efficiency for commercial buildings Fan speed control on heat rejection equipment Performance requirement Axial fan towers = 38.2 gpm/hp* Centrifugal fan towers = 20.0 gpm/hp* Axial fan closed circuit cooling towers = 14.0 gpm/hp* Centrifugal fan closed circuit cooling towers = 7.0 gpm/hp* Air cooled condensers = 176,000 BTU/h hp Based on 95/85/75 for towers, and 102/90/75 for closed circuit cooling towers, and 125/190/15/95 for air cooled condensers Slide No.: 32

33 ASHRAE Standard 189 Performance requirement Increased from 4-14% above ASHRAE 90.1 requirements Air Cooled condenser requirement removed and is dependent on tonnage Slide No.: 33

34 ASHRAE Standard 189 Once through cooling with potable water is prohibited. Cooling towers and evaporative condensers shall be equipped with make-up and blow down meters, conductivity controllers, and overflow alarms. Cooling towers shall be equipped with efficient drift eliminators: 0.002% of recirculated water for counterflow 0.005% of recirculated water for crossflow Slide No.: 34

35 California Title 24 Basis for energy efficiency for commercial buildings Same as ASHRAE 90.1 Flow turndown up to 33% Updated to make the flow turndown 50% Slide No.: 35

36 Limitations Centrifugal Fan Towers California Title gpm or higher must meet efficiency requirements of axial fans Air Cooled Chillers More than 300 tons of total capacity Only 100 tons provided by air cooled Slide No.: 36

37 Energy Saving System Designs. Slide No.: 37

38 EPA Climate Wise Program Wise Rules to Energy Efficiency Process Cooling Wise Rule 1. Installing energy efficient chillers and refrigeration systems can save 1.2% of a facility s total energy use with an average simple payback of 23 months. Slide No.: 38

39 EPA Climate Wise Program Wise Rules to Energy Efficiency Process Cooling Wise Rule 2. Free cooling with cooling tower water can reduce a facility's total energy use by about 1% with an average simple pay back of 14 months. Using cooling tower water in place of the chiller when the outside temperature is low Cooling tower is sized for winter capacity Slide No.: 39

40 EPA Climate Wise Program Wise Rules to Energy Efficiency Process Cooling Wise Rule 3. Free cooling can reduce cooling system energy use by as much as 40% depending on location and load profile. Process Cooling Wise Rule 4. Increasing chilled water temperature by 1 F reduces chiller energy use by 0.6% to 2.5%. Slide No.: 40

41 EPA Climate Wise Program Wise Rules to Energy Efficiency Process Cooling Wise Rule 5. Reducing condenser pressure by 10 psi can decrease refrigeration system energy use per ton of refrigeration by about 6%. Process Cooling Wise Rule 6. For each 1 F degree decrease in condenser cooling water temperature, until optimal water temperature is reached, there is a decrease in chiller energy use by up to 3.5%. Slide No.: 41

42 Installing VFDs in place of constant speed systems can reduce cooling system energy use by 30% to 50%, depending on load profile. Cooling tower fans Chiller compressor Energy Saving Tip Slide No.: 42

43 Single Speed BHP & VFD BHP Versus Wet Bulb Single Speed Motor BHP 20 VFD Wet Bulb Assumes constant load with varying wet bulb temperatures Slide No.: 43

44 Take advantage of ambient wet bulb temperatures Energy Saving Tip Slide No.: 44

45 ASHRAE 0.4% Wet Bulb Temperatures Location Baltimore, MD New York, NY Boston, MA Los Angeles, CA Seattle, WA Denver, CO Wet Bulb 78 F 76 F 75 F 70 F 66 F 65 F Slide No.: 45

46 ASHRAE 0.4% Wet Bulb Temperatures Location Baltimore, MD New York, NY Boston, MA Los Angeles, CA Seattle, WA Denver, CO Wet Bulb 78 F 76 F 75 F 70 F 66 F 65 F CWT 85 F 83.5 F 82.7 F 80.5 F 76.0 F 75.0 F Slide No.: 46

47 ASHRAE 0.4% Wet Bulb Temperatures Location Wet Bulb CWT Energy Baltimore, MD 78 F 85 F 0.57 kw/tr New York, NY 76 F 83.5 F 0.55 kw/tr Boston, MA 75 F 82.7 F 0.54 kw/tr Los Angeles, CA 70 F 80.5 F 0.53 kw/tr Seattle, WA 66 F 76.0 F 0.49 kw/tr Denver, CO 65 F 75.0 F 0.48 kw/tr Slide No.: 47

48 ASHRAE 0.4% Wet Bulb Temperatures Location Wet Bulb CWT Energy Savings Baltimore, MD 78 F 85 F 0.57 kw/tr Base New York, NY 76 F 83.5 F 0.55 kw/tr $2K Boston, MA 75 F 82.7 F 0.54 kw/tr $3K Los Angeles, CA 70 F 80.5 F 0.53 kw/tr $4K Seattle, WA 66 F 76.0 F 0.49 kw/tr $6K Denver, CO 65 F 75.0 F 0.48 kw/tr $9K Savings are based on 500 ton cooling tower with 10 F Range. Slide No.: 48

49 Energy Saving Tips Tip #1 Install energy efficient equipment. Tip #2 Evaluate additional free cooling hours. Tip #3 Increase chilled water temperature. Tip #4 Reduce condenser pressure. Tip #5 Lower the design condenser water temperature. Tip #6 Install VFDs on constant speed fan systems. Tip #7 Take advantage of low ambient wet bulb temperatures. Slide No.: 49

50 Conclusion Air-conditioning system evaluations should take the pending impact of environmental issues into consideration. Water cooled systems provide the most energy efficient systems and can help protect building owners and operators from uncertainties in electricity pricing. Slide No.: 50