Where Does CHP Make Sense?

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1 Where Does CHP Make Sense? Midwest CHP Application Center (MAC) (312) University of Illinois at Chicago Energy Resources Center

2 Overview CHP Systems are Often Installed for Two Reasons First Operating Cost Savings Second Some Site Specific Reason that Often Effectively Reduces the Installed Cost of the CHP Function We Will Be Looking at Both in Some Specific Building Markets

3 Some Needed Background Points 1. Loads - The Key to Positive Operating Economics 2. Installed Cost per kw for CHP Declines with Increasing System Size 3. CHP Can Supply Power Back-Up 4. CHP Can Supply Back-Up Cooling 5. Institutional Owners

4 Background on CHP System Operation

5 Example Simple Industrial Process Electric Load = 1,000 kw Heat Load 3 MMBH Assume a Generator Carrying the Full Electric Load 1,000 kw Generator Can Usefully Reject ~ 5.1 MMBH of Useful Heat Appears to Be Sufficient to Meet the 3 MMBH Heating Load

6 The Timing of the Electric Load kw Electric Load Weekdays 200 kw Electric Load Weekends Total Electric Load Duration Curve Total Electric Load (kw) Hrs/Year

7 Putting the Hours in Order of Electric Load Size Total Electric Load Duration Curve Total Electric Load (kw) kw Electric Load Weekdays 200 kw Electric Load Weekends All Weekdays Hours All Weekends Hours Hrs/Year in Order of Electric Load Size

8 When is Rejected Heat Available and How Much is Available? 6.E+06 Total Useful Rejected Heat From Full Time Generator 4.E kw Electric Load Weekdays 200 kw Electric Load Weekends Btu/Hr 2.E+06 All Weekdays Hours 0.E+00 All Weekends Hours Hrs/Year in Order of Electric Load Size

9 Now Lets Assume a Constant Process Heating Load of 3 MMBH 6.E+06 5.E+06 4.E+06 Total Useful Rejected Heat From Full Time Generator Constant Heat Load Btu/Hr Btu 3.E+06 2.E+06 1.E+06 0.E Hrs/Year in Oder of Electric Load Size Hrs/Year in Order of Electric Load Size Even When Used for a Simple Heating Load The Importance of the Timing of the Load is Clear

10 This Rejected Heat Can Never Be Productively Used 6.E+06 5.E+06 4.E+06 Total Useful Rejected Heat From Full Time Generator Constant Heat Load Btu/Hr Btu 3.E+06 2.E+06 1.E+06 0.E Hrs/Year in Oder of Electric Load Size Hrs/Year in Order of Electric Load Size

11 This Portion of the Heat Load Can Never Be Met by Rejected Heat 6.E+06 5.E+06 4.E+06 Total Useful Rejected Heat From Full Time Generator Constant Heat Load Btu/Hr Btu 3.E+06 2.E+06 1.E+06 0.E Hrs/Year in Oder of Electric Load Size Hrs/Year in Order of Electric Load Size

12 And the Area of any of these Block Represents the Quantity of Heat Involved 6.E+06 5.E+06 4.E+06 Total Useful Rejected Heat From Full Time Generator Constant Heat Load Btu/Hr Btu 3.E+06 2.E+06 1.E+06 0.E Hrs/Year in Oder of Electric Load Size Hrs/Year in Order of Electric Load Size Result 5.1 MMBH of Rejected Heat May Not Entirely Handle a 3 MMBH Heating Load Due to TIMING

13 Now for a More Realistic Example Commercial Building Example 300,000 SF Office in Chicago Electric Load in kw Timeline of the Electric Load Hrs/Year

14 Power Needs are More Easily Viewed by Ordering into a Duration Curve 1800 Total Electric Load (kw) Total Electric Load Duration Curve Entire Load Can Now Be Met by a 1625 kw Generator Hrs/Year Hrs/Year in Order of Electric Load Size

15 The Area Under the Curve Represents the kwh Consumed Over the Year 1800 Total Electric Load (kw) Total Electric Load Duration Curve Hrs/Year Hrs/Year in Order of Electric Load Size

16 If the Facility has a Generator that Supplies ALL Power Needs, How Much Waste Heat is Available? Total Heat Load (Btu/hr) 9.E+06 8.E+06 7.E+06 6.E+06 5.E+06 4.E+06 3.E+06 2.E+06 Waste Heat Avail from Generator Total Heat Load Duration Curve 1.E+06 0.E Recoverable Heat Hrs/Year from Generator Note: For Simplicity, the Engine is Assumed to Be Capable of Running Down to Zero Load at a Constant Efficiency and Heat Rejection Rate. This is Not True of Actual Engines

17 How Much of This Waste Heat Can be Used for the Space Heating? Total Heat Load (Btu/hr) 1.E+07 9.E+06 8.E+06 7.E+06 6.E+06 5.E+06 4.E+06 3.E+06 2.E+06 1.E+06 0.E+00 Waste Heat Avail from Generator Total Heat Load Duration Curve Recoverable Heat from Generator Heating Load Hrs/Year Only 13% of the Waste Heat is Recovered for Heating Coincident Waste Heat Use

18 If the Cooling Load is Now Also Operated by Waste Heat The Electric Load is Changed 1800 Total Electric Load (kw) Chiller Power Total Electric Use Except Chiller Total Electric Load Duration Curve The Chiller Consumes only 16% of the Total Electric Use but is Responsible for 28% of the Demand Entire Load Can Now Be Met by a 1185 kw Generator Hrs/Year

19 After Downsizing the Load and the Generator Total Heat Load (Btu/hr) 7.E+06 6.E+06 5.E+06 4.E+06 3.E+06 2.E+06 Waste Heat Avail from Generator after Replacing Electric Chillers with Absorbers Total Heat Load Duration Curve 1.E+06 0.E Hrs/Year Recoverable Heat from Generator

20 How Much of This Waste Heat Can be Used for the Space Cooling? Total Heat Load (Btu/hr) 1.E+07 1.E+07 8.E+06 6.E+06 4.E+06 2.E+06 Waste Heat Avail from Generator Waste Heat Used to Meet Cooling Load ONLY Total Heat Load Duration Curve 52% of the Waste Heat is Recovered for Cooling 0.E Recoverable Heat from Generator Hrs/Year Coincident Waste Heat Use

21 How Much of This Waste Heat Can be Used for the Space Heating AND Cooling? 1.E+07 1.E+07 Waste Heat Avail from Generator Waste Heat Used to Meet Cooling Load ONLY Total Heat Load Duration Curve Total Heat Load (Btu/hr) 8.E+06 6.E+06 4.E+06 2.E+06 68% of the Waste Heat is Recovered for Heating and Cooling 0.E Recoverable Heat from Generator Hrs/Year Coincident Waste Heat Use

22 In a Real Application 1800 Total Electric Load (kw) Total Electric Load Duration Curve Hrs/Year 1. Generator is Sized Well Below Full Load Size (50% Shown) 2. Generator Does Not Operate Full Time

23 In a Real Application 1800 Total Electric Load (kw) Total Electric Load Duration Curve Hrs/Year If We Operate a 50% Generator for All On Peak Hours Some Generator Capacity Exceeds Load

24 In a Real Application 1800 Total Electric Load (kw) Total Electric Load Duration Curve Hrs/Year Generator is Forced to Run at Part Load for Certain Hours

25 In a Real Application 1800 Total Electric Load (kw) Total Electric Load Duration Curve Hrs/Year Some Generator Capacity is Unused

26 The Installed Cost per kw for CHP Declines with Increasing System Size $2,500 MT Installed Cost ($/kw) $2,000 $1,500 $1,000 $500 CHP Generator Only CHP Using Recovered Heat for Heating Only Electric Capacity (kw) Engine Generators CHP Using Recovered Heat for Heating & Cooling

27 CHP Can Supply Power Back-Up Redirect Generator Output to Emergency Circuits During a Power Outage CHP Turns an OVERHEAD EXPENSE (Back-Up Generators) into a PROFITABLE ASSET

28 How Can CHP Serve as Back-Up Power? Normal Operation Electric Grid Continuously Operating Engine Generator Electric Power Paralleling Gear Non-Critical Building Loads Critical Loads Transfer Switch

29 How Can CHP Serve as Back-Up Power? During Power Outage Electric Grid Continuously Operating Engine Generator Electric Power Paralleling Gear Non-Critical Building Loads Critical Loads Transfer Switch

30 For CHP Systems Including Cooling Normal Operation Electric Grid Continuously Operating Engine Generator Paralleling Gear Non-Critical Building Loads Waste Heat Electric Power Critical Loads Absorption Chiller Transfer Switch Chilled Water for Air Conditioning

31 But CHP Offers Kicked-Up Back-Up During Power Outage the Absorption Chiller Continues to Cool Critical Loads without Consuming Generator Capacity Electric Grid Continuously Operating Engine Generator Paralleling Gear Non-Critical Building Loads Waste Heat Electric Power Critical Loads Absorption Chiller Transfer Switch Chilled Water for Air Conditioning

32 Why is Back-Up Getting More Desirable? Power Back-Up Used to Be Mainly for Hospitals Required Needed Mainly for Randomly Timed Natural Disasters, Ice Storms, Hurricanes, etc. Recent Additional Interest on Guarding Against Overloaded Grid Black-Outs and Brown-Outs Tend to Occur During the Hottest Weather» Hot Weather Often Makes Evacuation Difficult» Makes Backing Up the Cooling System More Important

33 Power Quality Some CHP Systems Can Deliver Very Consistent Power Improve Low Voltage Problems Cleaner Frequency Problems Importance? Operating the User s High Cost, High Tech Equipment More Safely Computers, Servers, Telecom Equipment, etc. Extending Equipment Life Reducing Equipment Failures

34 Institutional Owners CHP Paybacks Tend to Be in the 4-7 Year Range More Acceptable to the Long Term Planning Horizon of a an Institutional Owner than a Private For Profit Company

35 Hospitals Large Systems 24/7 Operation Need for Back-Up Power Institutional Ownership Longer Payback Horizon Good Thermal Loads

36 Universities Rutgers Large System Cost of CHP Declines with System Size Institutional Ownership Longer Payback University of Illinois at Chicago

37 Colleges & Universities with Cogeneration Albion College, Albion, MI, 360 kw Alvin Comm College, Alvin, TX, 1.0 MW Baylor Univ., Waco, TX, 3.3 MW Biola Univ., CA, 1.2 MW Brown Univ., Providence, RI, 3.25 MW Bucknell Univ., Lewisburg, PA, 600 kw California Institute of Technology, 11.0 MW California Polytechnic State Univ., 350 kw California State Univ.-Long Beach, CA kw Central Michigan Univ., Mount Pleasant, 950 kw Cerritos Community Coll., Norwalk, CA, 150 kw City of San Diego, San Diego, CA, 27 MW Claremont Colleges, Claremont, CA, 50 kw Clark Univ., Worcester, MA, 1.8 MW Colby College, Waterville, Maine, 100 kw College of Wooster, Wooster, Ohio, 375 kw Cornell Univ., Ithaca, New York, 8.5 MW Dartmouth College, Hanover, NH, 4.0 MW Dundee Univ., Dundee, Scotland Duquense Univ., Pittsburgh, PA, 5.0 MW Eastern Michigan Univ., Ypsilanti, MI, 4.0MW Elgin Community College, Elgin, IL, 3,2 MW Foothill-De Anza Community College, CA, 65kW Georgetown Univ., Washington, D.C., 2.8 MW Gordon-Conwell Theological Sem, MA Harding Univ., Harding, Arkansas, 5.2 MW Henry Ford Community College, Dearborn, MI. Highland Community Coll., Freeport, IL, 60 kw Hofstra Univ., Long Island, New York Illinois Central College, East Peoria, IL, 650 kw Illinois Institute of Tech., Chicago, IL, 8.0 MW Iowa State Univ., Ames, Iowa, 36 MW Loma Linda Univ., Loma Linda, CA, 10,600 kw Kansas State, Manhattan, KS, 3.0 MW MIT, 23 MW Michigan State,, MI, 12.5 MW Middlebury College, VT, 530 kw Montclair State, Montclair, NJ, 4.0MW New York Univ., New York City,, 7.0 MW Northeastern Illinois Univ. Norwich Univ., Northfield, VT, 300 kw Occidental College, Eagle Rock, CA Ohio State., Columbus, OH, MW Oklahoma State Univ., Stillwater, 9.5 MW Olds College, Olds, AL Palomar Comm Coll, San Marcos, 650 kw Pennsylvania State Univ., Univ. Park, PA Plymouth State College, NH, 1.25 MW Princeton Univ., Princeton, NJ, 14.0 MW Purdue Univ., West Lafayette, IN, 7.5 MW Rice Univ., Houston, TX, 4.5 MW Richard Stockton State College, Pomona, NJ Rutgers Univ., Camden, NJ Rutgers Univ., Newark, NJ Rutgers Univ., New Brunswick, NJ St. Lawrence Univ., Canton, New York, 350 kw Saint Mary of the Woods College, IN 750 kw St. Paul's School, Concord, NH, 2.3 MW San Diego State Univ., San Diego, CA, 2.6 MW San Jose State Univ., San Jose, CA, 6.0 MW Southeast Missouri State Univ., MS, 10.5 MW Southwest Texas State Univ. 12.4MW Springfield College, Springfield, MA, 450 kw Stanford Univ., Stanford, CA, 39 MW State Univ. of New York, Stony Brook, NY Texas A&M Univ., College Station, 36.5 MW Texas Tech, Lubbock, TX The College of New Jersey, Trenton, 3.2 MW The Hotchkiss School, Lakeville, CN, 135 kw The Rockefeller Univ., New York, New York Univ. of Medicine and Dentistry, NJ. Trent Univ., Peterborough, Ont, 2.5 MW Turabo Univ., Gurabo, PR, 38.0 MW Univ. of Alaska, Fairbanks, Alaska, 13 MW Univ. of CA, Berkeley, CA Univ. of California, Davis, CA 7.0 MW Univ. of California, Los Angeles, CA Univ. of California, San Francisco, CA Univ. of Calif., Santa Cruz, CA, 2.6 MW Univ. of Colorado, Boulder, CO, 33 MW Univ. of Florida, 42.0 MW Univ. of Illinois, 30.0 MW Univ. of Iowa, Iowa City, Iowa, 21.0 MW Univ. of Lethbridge, Lethbridge, Alberta Univ. of Maryland, Baltimore, Maryland Univ. of Mass, Amherst, MA, 3.6 MW Univ. of Mich, Ann Arbor, MI, 39.0 MW Univ. of Michigan, Dearborn, MI, 350 kw Univ. of Missouri - Columbia, 52.0 MW Univ. of Nebraska, Lincoln, 4.5 MW Univ. of New Mexico, 3.5 MW Univ. of North Carolina, 28.0 MW Univ. of Northern Colorado, Greeley, CO, Univ. of Northern Iowa, 7.5 MW Univ. of Notre Dame, Indiana, 32.0 MW Univ. of Oklahoma, Norman, 12.5 MW Univ. of Oregon, Eugene, 5.5 MW Univ. of San Diego, CA, 1.05 MW Univ. of San Francisco, 1.5 MW Univ. of South Florida, Tampa, MW Univ. of Texas, Austin, TX ~100.0 MW Univ. of Texas, South West Medical Center Univ. of Toronto, Toronto, Ontario, 8 MW Univ. of Washington, Seattle, 5.0 MW Univ. of West Virginia Univ. of Western Ontario, London, 1.6 MW Univ. of Wisconsin, Madison, WI, 3.0 MW Univ. of Wisconsin, Whitewater 285 MW Vanderbilt Univ., Nashville, TN. 11 MW. Virginia Polytech, Blacksburg, 24.0MW Wellesley College,, MA, 4.5 MW Wentworth Inst, of Tech., Boston, 660 kw Williams College, MA, 500 kw Ref: Cogeneration Consultants, Inc.

38 High Schools Institutional Ownership Longer Payback Horizon Desire for Power Back-Up a Safety Issue Pool/Showers/Cafeteria Loads Drive High Hot Water Consumption

39 Large High Rise Hotels 24/7 Load Large Year-Round Shower DHW Loads Centralized Chilled Water Systems

40 Other Health Care Sites Where Back-Up and Cooling Would be Desirable but May Not be Required Includes Nursing Homes, In-Patient Treatment, and Out-Patient Surgery Centers Desirable to Have Back-Up Power System which Includes Back-Up Cooling

41 Residential Confinement Non-Medical Sites Where Back-Up Power and Cooling Would be Desirable but May Not be Required Jails, Prisons, Mental Health Care, Drug Treatment Centers Anywhere the Occupants Cannot be Freely Evacuated During a Power Outage

42 Fitness Centers Moderate Electric Loads for Long Hours Large Pool Load Perfect Fit for Small CHP Packages Excellent Use of Waste Heat Heat Activated Cooling May Not Be Needed Public Gyms and Natatoriums Now Putting in Back-Up Power for Safety Reasons

43 High Reliability Loads Particularly Attractive Internet Server Farms, Computer Data Centers, Telephone Switching Centers Why? Huge Power and Cooling Loads Equipment Uses the Power and Dissipates It as Heat Air Conditioning Loads May be 20 Times What is Found in Typical Office Buildings Heating May Actually Not be Needed Even in the North

44 High Security Loads New Driver Concern about Sabotage or Terrorism Power Lines are the Obvious Target New Interest in Back-Up Power Focus Sites Military Installations, National Guard Armories, Police Stations, Airports Places of Public Assembly Auditoriums, Sports Arenas

45 How to Account for Added Benefits Situation: Evaluate a CHP System Versus Doing Nothing CHP System Includes Engine Generator Paralleling Gear All Heat Recovery Equipment Recovered Heat Driven Chiller Install CHP Do Nothing System Size KW Installed Cost of New System $0 $1,250,000 Operating Cost Savings $0 $150,000 Payback (yrs.) NA 8.33 Rate of Return NA 12.00%

46 What if Back-Up Power is Desired? Situation: Install a CHP System or Install Back-Up Engines Required: Install 1000 kw Backup Power Option: Install CHP System Size KW Installed Cost of CHP System $0 $1,250,000 Installed Cost of Back-Up $300,000 Included Total Cost $300,000 $1,250,000 Incremental Cost of CHP Function $950,000 Operating Cost Savings $0 $150,000 Payback (yrs.) 6.33 Rate of Return 15.79%

47 What About in a New Building? Situation: Add CHP System or Plan Conventional System (Incl. Back-Up) Required: Install 1000 kw Backup Power and Buy 3 New 200 Ton Chillers Option: Install CHP System and 2 New 200 Ton Chillers Size KW Installed Cost of CHP System $0 $1,250,000 Installed Cost of Back-Up $300,000 Included Installed Cost of Third Chiller $120,000 Included Installed Cost of New System $420,000 $1,250,000 Incremental Cost of CHP Function $830,000 Operating Cost Savings $0 $150,000 Payback (yrs.) NA 5.53 Rate of Return NA 18.07%

48 What if the Owner Wants Back-Up to Power at Least 200 Tons of Cooling? Situation : Without CHP, Back-Up Must Power the Chiller Required: Install 1120 kw Backup Power and Buy 3 New 200 Ton Chillers Option: Install CHP System and 2 New 200 Ton Chillers Size KW Installed Cost of CHP System $0 $1,250,000 Installed Cost of Back-Up $336,000 Included Installed Cost of Third Chiller $120,000 Included Installed Cost of New System $456,000 $1,250,000 Incremental Cost of CHP Function $794,000 Operating Cost Savings $0 $150,000 Payback (yrs.) NA 5.29 Rate of Return NA 18.89%

49 Summary CHP for Commercial Buildings Space Heating Alone is an Inadequate Use of the Heat Available Space Cooling Greatly Increases Heat Recovery Large and Consistent Heating Loads Could Also be used (Pools, Showers, etc.) To Best Exploit Benefits, CHP Best Installed In New Construction When Re-Doing Chiller or Back-Up Power Systems Specific Vertical Markets, Generally Requiring Power Back Up, May be the Best Applications

50 Commercial Building Markets Hospitals Fitness Centers Universities and University Campuses Medical Facilities with Critical Inpatient Care Residential Confinement High Security Buildings High Reliability Buildings High Schools High Rise Hotels

51 Industrial CHP Industrial Applications of CHP Generally Consist of Electricity and Heat Production with Minimal Cooling Systems Much Larger than Commercial Applications Fuels May be Natural Gas, Coal, or Some Industrial Waste Product

52 Industrial CHP Solid Fuels (Coal/Solid Waste) Use Steam Cycles Solid Fuel Burned in Boilers Creating High Pressure Steam for Steam Turbine Generators Exhaust Steam Passing to Production Uses Lower Cost Fuels Coal Generally ½ the Cost of Natural Gas Industrial Wastes May be Effectively Free Most Practical for Very Large Systems Fuel Handling and Boiler Operation Requires More Operator Labor Equipment is Generally a Larger Investment

53 Most Common Applications Metals 6% Food 10% Refining 13% Other 13% Industrial CHP Capacity by Application Paper 19% Chemicals 39% Pulp and Paper Mills Very Large Industrial Sites Chemicals Metals Food

Examples in Minnesota Boise Cascade 44 MW Lake Superior

54 Paper and Lumber Mills Fuels Bark, Sawdust, Waste Chips Generate Power and Steam Heating for Paper Processing Examples in Minnesota Boise Cascade 44 MW Lake Superior Paper 10 MW Potlatch Largest User of BioMass Fuel in North America

55 Very Large Industrial Sites Generally Coal/Steam or Gas Turbine Plants Fired Plants Purpose: Lower Cost Power and Various Heat Uses Examples in Minnesota Ford Twin Cities Assembly

56 Chemicals May be Coal or Gas Fired Plants Examples in Minnesota Archer Midlands Potential Growth Area Ethanol Production

57 Metals Source of Large Scale Power for Very Large Processing Facilities May Use Heat from Coking or Iron Making Process Often Large Enough to Export Power to the Wholesale Market Examples in Minnesota LTV - 2,000 MW

58 Food Processing Coors Power House Golden Colorado Food Processing Waste Boiler Babcock Borsig Purpose: Power and Large Supplies of Steam for Cooking Processes Examples in Minnesota Crystal Sugar 19 MW Southern Minnesota Beet Sugar 7.5 MW

Numerous Small Units in Minnesota Bio-Digester Gas at Water Treatment

59 Recycling and Renewables Trash to Energy Plant Landfill Gas to Energy Plant SRP Arizona Trash Incineration Landfill Gas to Power Systems Numerous Small Units in Minnesota Bio-Digester Gas at Water Treatment Plants Growth Area for Minn. Bio-Digestion for Large Farming Operations

60 The Revival of District Heating/Cooling/Power Plants Central Heat and Power Plant (175 MW) Philadelphia

61 Growth in District Heating/Cooling/Power System Location Initial Oper n DH DC Electric (City, State/Province) (year) (MWt) (Tons) (MWe) Trenton, NJ , London, Ontario ,215 4 Oklahoma City, OK ,100 1 Tulsa, OK ,150 1 Kansas City, MO ,000 6 Nassau County, NY , Baltimore, MD ,850 8 Chicago, IL ,800 3 Charlottetown, P.E.I Tampico, Mexico , College Park, MD , Many others: Indianapolis, Minneapolis, Nashville, St. Paul, etc.

62 Industrial Summary Variety of Heavy Industries Traditionally Use Cogeneration Waste as Fuel is Often the Key Effectively Capitalizing on a Renewable Resource

63 For More Information

REPRESENTATIVE CAMPUS PROJECTS Additional Information Available Upon Request

REPRESENTATIVE CAMPUS PROJECTS Additional Information Available Upon Request Table 1. Representative Burns & McDonnell Campus Central Energy/Utility Plant Experience Since 2000 Project Design Elements