where we are, where we could be, how we can get there. 12/14/2011

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1 Central Plant Optimization ASHRAE National Capitol Chapter - PES Wednesday, Nov 7, 2011 Dave Klee, LEED AP Director, Optimized Building Solutions Johnson Controls, Inc. 1 1 J o where we are, where we could be, how we can get there. 2 1

2 The Case for Central Plant Optimization HVAC provides the largest energy savings opportunity 3 The Case for Central Plant Optimization Within the HVAC system, Chiller plants provide the greatest energy savings opportunity. Within the chiller plant, the chiller provides the greatest opportunity. 4 2

3 Efficient and capable components can get you only so far. We must optimize at a system level. Automation & Optimization Variable Speed Drives Chillers Cooling Towers Pumps & Motors To maximize efficiency, plants must be designed and operated holistically 5 Meet the load with minimum power How optimization works 6 3

4 Meet the load with minimum power Simultaneously, without hunting Intelligent algorithms are required to optimally vary: Chilled water temps flow Condenser water temps flow simultaneously without hunting REDUCE: Chiller Energy Pump Energy System Energy Steam Energy Water Use 7 Measuring plant efficiency How do plants measure up? Legacy Chiller Plants Conventional Plants Efficient Plants Highly Efficient VSD Plants Average annual plant efficiency in kw/ton for chilled water plants includes total power consumption from chillers, all pumps and tower fans 8 4

5 Measuring plant efficiency: A real-world example of what s possible Month Ton-hrs Old kwh Old kw/ton Optimized kw/ton Savings Nov , , ,280 Dec , , ,147 Jan , , ,330 Feb , , ,272 Mar , , ,724 Apr , , ,140 May , , ,860 Jun , , ,559 Jul , , ,974 Aug , , ,478 Sep , , ,231 Oct , , ,880 Annual Totals 5,997,816 5,412, ,835,875 9 how to get there. 10 5

6 Is your design ready for optimization? Optimization starts with a firm design foundation Automate System Design Decisions Apply components effectively, optimally Select components effectively, optimally Design system infrastructure to max efficiency potential 11 Is your design ready for optimization? Optimization starts with a firm design foundation Automation Prerequisite Sequences The order of events Optimization Opportunity Algorithms The optimal events Design Decisions Executes Holds setpoints Meets the load Automate System Advises Calculates optimal states, speeds, setpoints Apply components effectively, optimally Meets the load with minimum power Select components effectively, optimally Today s standard Tomorrow s standard Design system infrastructure to max efficiency potential 12 6

7 Is your design ready for optimization? Optimization starts with a firm design foundation Automate System Design Decisions Apply components effectively, optimally Select components effectively, optimally Design system infrastructure to max efficiency potential 13 What is Optimization Ready TM? Optimization starts with a firm design foundation New construction: Plant infrastructure, components instrumentation and automation are designed such that when optimization software is applied, its performance is maximized and sustained. Existing buildings: Plant infrastructure, components, instrumentation and automation are upgraded such that when optimization software is applied, its performance is maximized and sustained. 14 7

8 Optimization is a process. Not a one-time event. Not just software. Not a bill of materials. Maintain Operating Decisions Measure & Verify Optimize System Automate System Design Decisions Apply components effectively, optimally Select components effectively, optimally Design system infrastructure to max efficiency potential 15 Optimization works in New Construction and Existing Buildings: Design or retrofit to get to optimization ready. Then optimize. New Construction 1. Design Efficient System 2,3. Select & Apply Equipment Effectively 4. Automate with Proven Algorithms 5. Add Optimization Software 6. Measure, Verify & Manage 7. Maintain Start with Sound Design Decisions Optimize Existing Buildings 1. Correct System Deficiencies 2,3. Correct Equipment Deficiencies 4. Automate with Proven Algorithms 5. Add Optimization Software 6. Measure, Verify & Manage 7. Maintain Address pre-existing conditions Optimize 16 8

9 Read the whitepaper: Maintain Operating Decisions Measure & Verify Optimize System Automate System Design Decisions Apply components effectively, optimally Select components effectively, optimally Design system infrastructure to max efficiency potential 17 Know our enemies. Operating Decisions Maintain Measure & Verify Optimize System Automate System It s not working! We can do that! Already optimized! Design Decisions Apply components effectively, optimally Select components effectively, optimally Design system infrastructure to max efficiency potential 18 9

10 Maximize your potential. 19 Step 1: Design efficient system infrastructure Which system configuration is most likely to deliver the most efficient plant? 1. Design efficient system infrastructure Chilled Water System Headered Dedicated Variable Primary A B Primary / Secondary C D Constant Primary E F Condenser Water System Headered Dedicated Variable Flow 1 2 Constant Flow

11 Step 1: Design efficient system infrastructure Which system configuration is most likely to deliver the most efficient plant? 1. Design efficient system infrastructure Chilled Water System Headered Dedicated Variable Primary B Primary / Secondary C D Constant Primary E F Condenser Water System Headered Dedicated Variable Flow 1 2 Constant Flow Step 1: Design efficient system infrastructure Which system configuration is most likely to deliver the most efficient plant? 1. Design efficient system infrastructure Chilled Water System Headered Dedicated Variable Primary B Primary / Secondary C D Constant Primary E F Condenser Water System Headered Dedicated Variable Flow 2 Constant Flow

12 Steps 2&3: Once you have efficient system design, Evaluate & select components on a real-world basis 23 Step 5: Central Plant Optimization Some characteristics are nearly universal The load is met. Comfort and safety not impacted Whole-system approach (chillers, pumps & towers) All-VSD plants best performance Effective BAS is in place; capable of control and data gathering Standardized solution (not one-off, custom) Adjustments are made automatically Adjustments are made continuously 24 12

13 Step 5: Central Plant Optimization The nature & basis of algorithms will vary How are optimization decisions made? Some focus on primarily on pumps Proven best-in-class practices Equipment efficiency curves Energy-based sequencing Proportional/ integral/ derivative Adaptive tuning loops PID loops Relational control Transparent or proprietary 25 Step 5: Central Plant Optimization The solution architecture will vary Where do the algorithms reside? Inherent in the BAS Add-on appliance (usually on site) Where does the data flow? Within the BAS BAS server collects data BAS server serves up info to dashboard / reports Within the cloud Local appliance transmits Internet Remote server collects & serves up info to dashboard / reports 26 13

14 Central Plant Optimization Solution Architecture Example Metasys or 3 rd party BAS: Building Automation System CPO: On-site Optimization MVM: Measurement, Verification and Management Internet Chillers Client Desktop Internet VSDs on pumps, cooling tower fans Sensors, Meters & Controlled Devices Customer site Customer Service Center 27 Step 5: Central Plant Optimization Other critical evaluation criteria Reliability structured commissioning process Stability Stable operation and persistent performance Repeatability not reliant on individuals expertise Predictability performance is understood, proven Visibility measurement, verification and management 28 14

15 Step 6: Measure, Verify & Manage performance Actionable information to empower sustained performance Web-based UI for remote access Remote monitoring and diagnostics Real-time trends; Periodic reports Alert notification & escalation UI representing actual plant layout Actionable info, tailored to users needs. Long-term data storage and management Energy consumption & cost Weather data and load profiles Equipment runtime, starts, stops 29 Step 6: Measure, Verify & Manage performance Actionable information to empower sustained performance 30 15

16 Step 7: Maintain Sustain the value of the investment in optimization Run to fail Repairs to equipment not included in plan Necessary repairs made reactively upon failure Scheduled maintenance Focus on component care Performed regularly Predictive Services Strategy focus uptime and performance Proactive management Elimination of equipment failure 31 Case Study Projects 32 16

17 Optimization Case Study: Cleveland State University Situation 3,800,000 sq. ft. campus in Cleveland, OH Most load is 7am to 10pm, but laboratory and student housing load is 24/7. Solution Two 2,750-ton, one 1,000-ton Yorks; Two 1,000-ton Tranes. All Metasys. Implemented OptimumHVAC / CPO 30 Result Est. energy use savings: 910,000 kwh/yr Est. first year savings: $113,000 To-date improved kw/ton: 36% Simple payback for the entire project: 2.7yrs 33 Optimization Case Study: University of Texas at Austin Situation District Cooling station serving 135 buildings (17 million sq ft ) Total campus load:145 million ton-hours / year Rising energy prices, increasing cooling load Solution Replaced plant with a new, all-vsd plant Installed 3 new 5000 ton York Titan chillers Johnson Controls / OptimumLOOP Result Plant efficiency: 0.33 to.87 kw/ton, depending on wet bulb and campus load Estimated first year savings: 5 million kwh Simple payback for LOOP install: 12 months 34 17

18 Optimization Case Study: Sotheby s Building Situation 470,000 sq. ft. facility in New York City Houses rare antiques & priceless art Needed a reliable, efficient chiller plant Solution VSD retrofits on two 700-ton York centrifugal chillers, cooling tower fans, condenser water pumps and chilled water pumps. Implemented Central Plant Optimization. Result Qualified for incentives: $167,000 Est. first year savings: $201,000 To-date improved kw/ton: 31.7% Simple payback for the entire project: 3.6 yrs 35 Navigate the process

19 Johnson Controls CPO Ideal Targets for CPO Large buildings / plants (>600T) Multiple, centrifugal chillers High loads (base & peak) High operating hours (day/ wk/ yr.) Data centers (or bldgs with them) Process loads (served by plant) Existing BAS (not manual control) LEED or other green mandates Funding for efficiency / expense reduction projects Rebate programs, High utility rates 37 CPO is an Engineered, Financial Solution Engineering & Implementation Process Assess. Analyze. Design. Implement. Save. Optimization Optimization Optimization Optimization Optimization Preliminary Assessment Is the site a candidate for optimization? Financially? Technically? Analysis and Design What are the design requirements for optimization? What are the business requirements of the project to ensure success? Architecture Proposal Provides a comprehensive energy appraisal and an actionable plan that outlines the technical approach and business case for optimization. Implementation Phased approach that includes: Mechanical upgrades Controls integration Network appliance & software install Testing and remote commissioning Continuous Commissioning Benefits: Eliminates performance drift Ensures optimum energy efficiency Provides real-time plant analytics Enables remote diagnostics $ $ $ 38 Johnson Controls, Inc. 19

20 12/14/ Central Plant Optimization ASHRAE National Capitol Chapter - PES Wednesday, Nov 7, 2011 Dave Klee, LEED AP Director, Optimized Building Solutions Johnson Controls, Inc J 0 o h 20