M&V Real Results of High Performance Design Matt Cooper, PE, BEMP, HBDP, Group 14 Engineering Ken Urbanek, PE, HBDP MKK Consulting Engineers, Inc.
Overview Measurement & Verification (M&V) Plan for New Construction M&V - Design Specifications M&V - Construction and CX Requirements M&V - Case Study
Why M&V? Many LEED buildings are not achieving anticipated energy savings Source: New Buildings Institute and U.S. Green Building Council
EA Credit 5 for New Construction IPMVP Volume III: Concepts and Options for Determining Energy Savings in New Construction, April 2003 Option D: Calibrated Simulation (Energy Estimation Method) Suitable for building with large number of ECMs or interacting systems Option B: Energy Conservation Measure Isolation Small and simple projects ECMs have insignificant or no interaction
EA Credit 5 for New Construction M&V Plan minimum requirements Table or listing of the project s energy end use Method used to model the baseline energy consumption Model calibration method and party responsible Baseline conditions Data collection method/frequency Corrective action strategies if data deviates M&V must cover a minimum of one year post-occupancy
M&V Team Who should write the Plan? M&V Agent Develop M&V Plan Design, submittal and installation reviews Cx the M&V system Assemble M&V data set(s) Troubleshoot M&V report Owner training Energy Engineer/Modeler Create energy model Calibrate models to sub-meter & weather data Owner Ensure M&V data continues to be collected Continuous education Utilization of data
M&V Plan Getting Started The M&V Approach document M&V Workshop What information is needed to write the plan? Modeled energy cost by end-use List of Energy Conservation Measures Estimate of M&V implementation costs
Energy End-Use Cost Table ENERGY COST TOTAL COST OF ENERGY BY END-USE Equipment Lighting Water Heating Heating Cooling Fans Pumps Total Jan $1,024 $683 $23 $628 $2 $376 $37 $2,772 Feb $995 $621 $22 $560 $2 $355 $31 $2,587 Mar $1,051 $612 $26 $475 $6 $344 $33 $2,546 Apr $1,069 $498 $26 $245 $93 $363 $26 $2,320 May $1,051 $465 $24 $133 $261 $317 $28 $2,279 Jun $1,125 $506 $25 $91 $360 $369 $28 $2,501 Jul $1,129 $507 $25 $42 $461 $411 $31 $2,604 Aug $1,116 $515 $23 $54 $458 $420 $30 $2,614 Sep $1,111 $522 $21 $106 $377 $443 $28 $2,608 Oct $1,060 $505 $21 $219 $112 $458 $28 $2,402 Nov $1,000 $502 $19 $340 $67 $459 $27 $2,413 Dec $1,060 $715 $23 $578 $3 $371 $30 $2,780 Annual $12,789 $6,651 $278 $3,470 $2,203 $4,687 $356 $30,433 % of Annual 42% 22% 1% 11% 7% 15% 1% -
Assessing Performance Risk The cost of an M&V program must be balanced against the added energy cost of a poorly performing building High Risk High % of annual energy costs Daylight Dimming Control CO 2 Ventilation Control VAV Air Handlers Condensing Boilers Under Floor Air Distribution Solar Thermal Systems Economizer Free Cooling Low Risk Low % of annual energy costs Exhaust Fans Heat Recovery Ventilators Single-Zone RTUs Non-Condensing Boilers Elevators Photovoltaic Systems Service Water Heating
M&V Plan Getting Started Encourage load segregation on electric panels. Does specified equipment have energy monitoring options?
M&V Plan Getting Started Minimize the number of sub-meters. Source: http://www.xcelenergy.com/save_money_&_energy/for_your_business/additional_programs/infowise_from_xcel_ EnergySM
M&V Plan Getting Started Using your Building Automation System (BAS) for M&V Snow-melt System Example:
M&V Plan Getting Started Using your Building Automation System (BAS) for M&V VAV Electric Reheat Example:
M&V Plan - Data Point Matrix Equipment Point Description Source Type Typical Unit Type(s) BAS I / O Notes: BAS Calculation Elec Bldg Electrical Energy Electric Meter kw/kwh AI Sub-meter or main breaker provides both kw and kwh to BAS for entire building. Record at minimum 5 min intervals. - Gas Bldg Gas Energy Utility Bill therms Manual Owner to input into BAS at GUI. TC to Input provide input fields (Dates and therms) - Boilers Building Heating Energy Gas Submeters intervals BAS records therms at minimum 5 minute therms AI BAS Outdoor Air Temp Temp Sensor(s) F AI Provide for each OAT sensor. If multiple devices, provide average of sensor values. RTU-1 Return Air CO2 CO2 sensor ppm AI - - RTU-1 Return Air Temp Temp Sensor F AI - - RTU-1 Exhaust Fan Energy VFD Output or Current xfmr kw / kwh AI BAS records kw at 5 min intervals. kwh calculated as average of hourly kw readings. RTU-1 Exhaust Fan Speed Setpt BAS Command % or Hz AO - - RTU-1 OA Damper Position BAS Command % AO - - RTU-1 OA Airflow AFMS CFM AI - - RTU-1 Mixed Air Temp Temp Sensor F AI - - RTU-1 Supply Fan Energy VFD Output or Current xfmrs kw / kwh AI BAS records kw at 5 min intervals. kwh calculated as average of hourly kw readings. RTU-1 Supply Fan Speed Setpt BAS Command % or Hz AO - - RTU-1 Heating Valve Position BAS Command % AO - RTU-1 Discharge Air Temp Temp Sensor F AI - - RTU-1 Discharge Air Setpt BAS Command F AO - -
M&V Plan M&V Operator Interface To facilitate ongoing energy management, include pre-programmed energy summary graphics.
M&V - Design Specifications Pre-Plan Effort Ensure that M&V is covered in your contract! Determine the E.T.A of the official M&V Plan. Deliverables Prior to the M&V Plan? Ensure that these deliverables (Planning Scope, SD Narratives, Pricing Documents, etc ) include an initial, if only ball-park, estimate of the M&V design requirements. Attempt to be clairvoyant about what will be in the M&V Plan cover this information.
M&V - Design Specifications Plan Creation Effort It is ok for the Design team to Review and Comment on the written M&V Plan. It isn t written in stone. Keep the following in mind when reviewing: What data are we trying to measure? What are the various ways that we can obtain this or similar data? What is the best way to obtain this information? Buying more meters isn t always the best solution. Weigh: dollars, accuracy, % of the energy pie, etc Don t spend $$$$ tracking down the energy use of a small domestic hot water system will this effort pay back?
M&V - Design Specifications Post-Plan Effort, i.e. implementing the plan direction. The M&V Plan should outline what is required for: Drawings & Specifications Critical Control Interface Requirements Big Picture, the M&V Plan can be broken down into energy utilities This allows for distribution among the design team who is covering what systems These energy utilities can be further broken down into system uses
M&V - Design Specifications Starting Simple moving towards the more complicated Water Domestic Water Use Process Use (cooling towers, etc ) Irrigation Gas (or Propane) Gas Heating Domestic Hot Water Process (kitchen, autoclaves, etc ) Electric Power Lighting Plug loads Major Mechanical
M&V - Design Specifications Water: Domestic Water Use Only: Normally this information can be obtained from utilities. If that is all you have you are done. Process Use, example Cooling Tower The cooling tower use can be measured by providing a sub-meter on the cooling tower feed. This amount can be tracked via the BAS. This amount can be taken from the utility total thus giving an indication of the normal domestic water use.
M&V - Design Specifications Gas (or Propane): Gas has a low performance risk Propane on the other hand has a HIGH Performance Risk Heating use Only: Furnaces or Heating Boilers Normally this information can be obtained from utilities. No short term requirements, just monthly therm use If that is all you have you are done. One might consider providing a meter on this system if there are numerous gas uses.
M&V - Design Specifications Gas (or Propane) - Continued: Complicated Gas Heating Systems, Example Central Boiler Plant: Serving terminal heating, outside air heating, snowmelt, domestic hot water generator, etc These individual uses can be measured using BTU Meters on the hydronic side. The total of the BTU Meters should be equivalent to the gas utility measurements
M&V - Design Specifications Gas (or Propane) - Continued: What does that look like?
M&V - Design Specifications Gas (or Propane) - Continued: What does that look like?
M&V - Design Specifications Gas (or Propane) - Continued: What does that look like?
M&V - Design Specifications Gas (or Propane) - Continued: What does that look like?
M&V - Design Specifications Gas (or Propane) - Continued: Domestic Hot Water Gas Fired: Small use is a low performance risk Little to gain by monitoring $100 to $500/yr of water heating Larger Domestic Hot Water Systems, Example: Commercial Kitchen or Laundry Provide a gas meter at the water heater(s) This amount can be tracked via the BAS. This amount can be taken from the utility total thus giving an indication of the normal domestic water use.
M&V - Design Specifications Electric Power 3 Major Categories Lighting
M&V - Design Specifications Electric Power 3 Major Categories Plug loads
M&V - Design Specifications Electric Power 3 Major Categories Major mechanical
M&V - Design Specifications Electric Power Continued: Perfect World Basic Approach: Even more Perfect World we would monitor energy use at every circuit in the building!
M&V - Design Specifications Electric Power Continued: We live in a Non-Perfect World and need to think outside the box. What are some other approaches? For Plug there isn t a lot other than a meter OR subtraction: For Lighting we can Monitor run-time for fixed output lamps. Interface via the BAS to the lighting control system and pull usage.
M&V - Design Specifications Electric Power Continued: For Major Mechanical we can Pull kw usage directly from major components, i.e. Chillers Pull kw usage directly from VFDs NOTE: You must ensure this kw point is actually pulled to the BAS and is available from the VFD. Pull Amps using a current transducer, convert to kw Pull run time using a current switch for fixed output devices. Flow and temperature change calculations also work. However you must specify the components and specify what needs to be pulled by the BAS.
M&V - Design Specifications Electric Power Continued: Difficult Mechanical Components To Look Out For Fan Powered VAV Boxes Split Systems CRAC Units Terminal Heaters Electric OR Hydronic Exhaust Fans Etc.Pretty much any item that is distributed out in the building. Asses the Performance Risk of these difficult components Implement different approaches accordingly
M&V - Design Specifications We have determined how to get information NOW we must collect, store, access and interpret All of this requires controls A few things to keep in mind The controls contractor cannot read your mind! You must tell them what you want, for instance: Grab a particular piece of data Record that piece of data at this interval Store that piece of data for this long. Make the following computations with that data Report the results of these computations and data streams You must tell them what to do to meet the M&V plan requirements.
M&V - Design Specifications Control Point Matrix Example Point Water Heater Gas Meter Collected Data Calculated Data Trend Interval Storage Timeframe Reporting CFH Therms Hourly 24 Months Daily Use, 3 Month Interval
M&V - Construction and CX Requirements Design Team Role Submittal Phase Verify that the design specifications for M&V are covered by the various contractors: mechanical, electrical, controls, etc Pay close attention to special requirements on individual pieces of equipment, examples: Does the chiller have an electrical meter submitted with it? Is this meter being picked up by the controls contractor? Did you specify any special requirements with the VFDs? Are these picked up by the controls contractor? Design Team Role Construction Observation Verify that the design specification for the M&V are being installed. Again pay close attention to special details, example: Are water meters being installed for cooling tower feed or direct/indirect AHUs?
Construction Cx of M&V M&V Agent Role Submittal Phase Confirm all measuring devices submitted Submitted equipment meets the M&V Plan Intent M&V Agent Role Construction Phase Commission devices Verify trends and interval rates Confirm data archiving and backup M&V Agent Role Occupancy Phase Reconfirm data collection Data Analysis
Case Study Supermarket in Maine Energy conservation Measures: Refrigeration Heat Recovery Dual-Path Dehumidification Tubular Daylight Devices & Daylight Dimming Controls Low-Heat Refrigerated Case Doors Floating-Head Condenser Control Glass-Door Medium Temperature Cases
Case Study Supermarket in Maine kwh is 95% of energy costs Focus on Daylighting & Dual Path HVAC Trended HVAC, lighting, and refrigeration data August 2011 Sub- Meter kwh % of Total kwh Sub-Meter Data Source House Electric Meter 310,836 100% Meter Bldg Gas Meter 7,830 Meter Water Meter 1,628 Meter Sales Area Lighting 0% Circuit-1 32,509 10% Meter Circuit-2 10,482 3% Meter Exterior Lights 3,007 1% Meter Warehouse Lighting 10,439 3% Fixture kw & Run Time Other Space Lighting 15,714 5% Fixture kw & Run Time Sales AHUs & CUs DPAH-1 8,327 3% Meter DPAH-2 14,985 5% Meter DPAH-CU-1 29,091 9% Meter DPAH-CU-2 22,157 7% Meter Other HVAC Systems 6,849 2% Fan & CU run times Misc Process Loads 24,000 8% Assumed Refrigerated Cases 57,110 18% Meter Compressor Rack-1 17,931 6% Meter Compressor Rack-2 8,797 3% Meter Compressor Rack-3 17,454 6% Meter Compressor Rack-4 19,019 6% Meter
Case Study Supermarket in Maine
Case Study - Supermarket
Case Study Supermarket in Maine Model Calibration Performance Issues Daylighting controls not performing correctly Dual path dehumidification poorly controlled Modeling Issues Store operating hours modified Warehouse is not cooled Anti-sweat heater use over predicted
Case Study Supermarket in Maine
Case Study Office Energy conservation measures: High-Efficient Lighting Daylight dimming controls Demand Controlled Ventilation Variable Refrigerant Flow / Volume Underfloor Air Distribution Heat Recovery Ventilator
Case Study - Office Energy End Use Lighting (Interior and Exterior) Space Heating/Cooling (VRF) Ventilation - Heating (Gas) Ventilation - Cooling (Evap) Domestic Water Heating (Gas) Fans Pumps Plug Loads Measurement Method Electric Sub-meter Electric Sub-meter Monthly Utility Meter Data Water sub-meter None VFD Outputs None Estimated by Subtraction
Case Study - Office Lighting Controls Cx identified 12 deficiencies. Contractor maintained installation, is per design.
Case Study High-Rise Office Energy conservation measures: Spectrally Selective Glazing High-Efficient Lighting Daylight dimming controls Demand Controlled Ventilation Frictionless Centrifugal Chillers 92% Efficient Condensing Boilers 50 F delta T Heating System Energy Star Office Equipment
Case Study High-Rise Office Energy End Use Lighting (Interior and Exterior) Cooling Fans Pumps Domestic Water Heating (Gas) Space Heating (Gas) Space Heating (Elec) Plug Loads Measurement Method Central Lighting Control System BAS interface with Chiller controls and Cooling Tower VFDs BAS interface with fan VFDs BAS interface with pump VFDs None Utility s Energy Meter Data Calculated from VAV box trend data Sub-meter on bus duct serving office floors less lighting and electric reheat energy
Thank you!