Navigating Vermont s New Core Performance Guide. Session Overview 2/18/2008

Transcription

1 Navigating Vermont s New Core Performance Guide Jonathan Kleinman, Efficiency Vermont Mark Frankel, New Buildings Institute Better Buildings by Design Conference Burlington, VT February 13, Session Overview Core Performance What is it? Who developed it? Core Performance Overview Vermont s Core Performance Development Core Performance Finalizing the Prescriptive Approach Working with Efficiency Vermont 2 1

2 Easy Cost Effective Path to Efficiency AB Core Performance provides a guided path to achieving energy performance that is 20-30% above the performance called for in Vermont Energy Code and ASHRAE Cost-effective paybacks less than 5 years even without incentives Paybacks under 2 years possible with utility incentives. A detailed, step-by-step process 3 Energy Efficiency Made Easy!!!! Familiar process Values and criteria parallel standard building code requirements for HVAC, Lighting Envelope A&E s can design for efficiency without becoming energy consultants Owners can get efficiency without hiring energy consultant Demonstrated cost effectiveness No modeling required! Provides information about products and strategies to meet performance targets 4 2

3 How was the System Developed? o Led by New Buildings Institute o Volunteer effort by A&E practitioners across US o Proven through prototype DOE-2 simulations and real projects o Version 2 Core (July 2007) builds on success of Benchmark (2005) o NBI and VEIC built Vermont-specific analysis to verify savings 5 Building Characteristics Project Size By Number of Projects By Total Floor Space 25,000 sf or Less 89% 37% 50,000 sf or Less 95% 50% Source: CBECS

4 3 Core Performance prototypes Office Two-story building, 20,000 square feet Five HVAC configurations PVAV-gas and electric, PSZ-gas and electric, PHP School Elementary school 50,000 square feet Four HVAC configurations WLHP-gas boiler and cooling tower, PVAB-gas boiler, PSZ-gas and electric Retail One-story building, 12,000 square feet Sales and storage areas Three HVAC configurations PHP, PSZ-gas and electric 7 Energy Modeling All analysis uses equest to run DOE-2 Batch analysis protocol runs multiple permutations on each prototype and subsystem New software developed to rank measures for energy performance impact Baseline for ASHRAE and 2004 for each prototype 8 4

5 Permutations Climate data from 15 cities (TMY) to represent 7 ASHRAE climate zones and permutations Three prototypes with multiple system variants each (total of 11 variants) 16 EEM s, run repeatedly until ranked (136 combinations) Two baselines Total = Approximately 25,000+ DOE-2 runs! 9 Measures Evaluated Measures From ABv1.1: Lighting Power Reduction Vertical Fenestration Performance Opaque Wall and Roof Performance Cool Roof High Efficiency Package Air Conditioner High Efficiency Furnace High Efficiency Package Heat Pump Variable Speed Drive Fans VSD Pumping New or Revised Measures: Occupancy Sensors Daylighting Controls Warmest Zone Reset High Efficiency Boiler Heat Recovery Indirect Evaporative Cooling Demand Control Ventilation Night Ventilation South Overhang Plug Load Reduction (EPD) 10 5

6 Representative cities 11 Core Performance results Core Performance Modeling Results Savings over % 40% 35% 30% 25% 20% 15% 10% 5% 0% Climate Zones 1-8 Office School Retail 12 6

7 Core Performance Guide Overview 13 Outline of Guide o Introduction o Program development and Summary o Prescriptive Measure Sections o Design Process Strategies o Core Performance Requirements o Enhanced Performance Strategies o Modeling o Appendices 14 7

8 Applicability Core Performance Page Quick Start Guide Brief Explanation of All Criteria 16 8

9 Relationship to LEED Created by NBI, coordinated with USGBC Adopted by USGBC for LEED NC Points Latest LEED NC energy requirements: Mandatory Requirement: Now 14% above ASHRAE Prescriptive alternative for 2-5 points in LEED Energy and Atmosphere credit 1 Energy Modeling not Required LEED is strictly an OPTIONAL companion for Advanced Buildings 17 Appendices o More detail on Acceptance Requirements o The Climate Zone Map on which many requirements are based o And very important an explanation of the acronyms and technical terms used throughout the text 18 9

10 Dual Use of the Term Core The Core Performance Guide contains criteria for 3 levels of approach: 1. Core Criteria (2.1 to 2.13) 2. Enhanced Criteria 3. Modeled Criteria Core Approach equates with the basic Core Performance section excluding the Enhanced and Modeled sections 19 Core Performance Criteria 2.1 Energy Code Compliance 2.2 Air Barrier Performance 2.3 Minimum IAQ Performance 2.4 Below Grade Exterior Insulation 2.5 Opaque Envelope Performance 2.6 Fenestration Performance 2.7 Lighting Controls 20 10

11 Core Performance Criteria 2.8 Lighting Power Density 2.9 Mechanical Equipment Efficiency Requirements 2.10 Dedicated Mechanical Systems 2.11 Demand Control Ventilation 2.12 Domestic Hot Water System Efficiency 2.13 Fundamental Economizer Performance Energy Code Compliance Meet or exceed Vermont Energy Code or ASHRAE/IESNA Standard or the IECC 2006 (whichever is more stringent) 22 11

12 2.2 Air Barrier Performance HVAC Reduce uncontrolled air movement through the building envelope to: Control humidity and temperature Reduce energy losses Requirements: Similar to Code Minimum IAQ Requirements Follow ASHRAE IAQ Construction Management Plan Pre-occupancy Flush Out Plan Ongoing IAQ Operations Management Plan 24 12

13 2.4 Below Grade Exterior Insulation Establishes minimum insulation R-value Similar to Vermont Code Targeting Energy and IAQ performance Buildings designed specifically for youth or elderly Buildings with periods greater than 7 days when mechanical systems are shut down Buildings that don t have a mechanical cooling systems Opaque Envelope Performance HVAC Meet specific insulation criteria for each building envelope assembly Requirements align with Vermont Code Insulation requirements vary by climate. (All guidelines exceed ASHRAE criteria) 26 13

14 2.6 Fenestration Performance Criteria Metal Framed U-Value 0.45 (Assembly) SHGC 0.30 Daylighting Simulation Necessary if Glazing Exceeds 40% of Wall Area All guidelines exceed Vermont and ASHRAE criteria Lighting Controls HVAC All areas of the building must incorporate the following three switching and control strategies: 1. Bi-Level Switching 2. Separate Switching at Daylit Areas 3. Automatic on/off Controls for unoccupied conditions Skylit areas 1. Must have automatic daylight control Daylit areas are encouraged to incorporate daylight controls, but at a minimum these areas must be provided with separate switching to facilitate future incorporation of daylight control systems 28 14

15 2.8 Lighting Power Density HVAC Projects may not exceed the lighting power density limits indicated in Table LPD = Lighting Power Density (connected/ installed lighting watts / square foot) Calculation includes combined energy use of lamp and ballast systems Light Power Density LPD values are given for both whole building and space-by-space analysis Prescriptive LPD Values 30 15

16 2.9 Mechanical Equipment Efficiency HVAC Mechanical equipment must meet the performance Criteria described in Tables Efficiency Tables 32 16

17 2.10 Dedicated Mechanical Systems HVAC Isolate load driven systems (process loads) from comfort HVAC systems In a recent case, this strategy first cost was $9,000, and annual savings was $15, Demand Controlled Ventilation (DCV) Manage outdoor airflow rate based on occupancy (except in Economizer mode) Install real time ventilation controls in single zone systems to reduce OA when CO2 sensors in the space indicate FA is adequate for the current occupancy (Maintain a range of 800 to 950 ppm) Follow recommendations of ASHRAE 62 Exceptions allowed for in appropriate situations / conditions 34 17

18 2.12 Domestic Hot Water System Efficiency Install demand water heaters (tankless) for small or isolated loads Install high efficiency, sealed combustion or condensing hot water heaters for larger systems Fundamental Economizer Performance Economizer or Air Side Free Cooling Key Requirements Robust, fully functional equipment Fully modulating damper motor Use direct modulating actuator with gear driven interconnects Coordinated, differential and proportional control using analog sensor upstream of cooling coil Dual-enthalpy control Provide relief air capability 36 18

19 Design Process Strategies 37 Design Process Optimization 1.1 Identify Design Intent 1.2 Communicating Design Intent How to get the whole development team on board with the energy goals for the project. How to carry these goals through the project to completion 38 19

20 Building Optimization 1.3 Building Configuration 1.4 Mechanical System Design Right Sizing is Critical 39 Quality Assurance 1.5 Construction Certification (Acceptance Testing) 1.6 Operator Training and Documentation 1.7 Performance Data Review 40 20

21 Enhanced Performance Strategies 41 Why Enhanced Performance? Not universally applicable like Core Comparable value in proper project Extra Savings beyond Core s demonstrated values Also First Picks for Modeling Approach 42 21

22 Enhanced Performance Strategies 3.1 Cool Roofs 3.2 Daylighting and Controls 3.3 Additional Lighting Power Reductions 3.4 Plug Load / Appliance Efficiency 3.5 Supply Air Temperature Reset (VAV) 3.6 Indirect Evaporative Cooling 3.7 Heat Recovery 43 Enhanced Performance Strategies 3.8 Night Venting 3.9 Premium Economizer Performance 3.10 Variable Speed Control 3.11 Demand Responsive Building 3.12 On-site Supply of Renewable Energy 3.13 Additional Commissioning Strategies 3.14 Fault Detection Diagnostics 44 22

23 3.2 Daylighting in Core Performance Integrate daylight controls at all side- and top-lit daylight areas Integrate skylights in occupied upper floor areas (up to 3-5% of floor area) Implement solar control Test and calibrate controls Additional Lighting Power Reductions Reduce connected lighting loads to achieve the lighting targets of the Energy Policy Act of Connected Watts/ SF roughly 40% below ASHRAE (Code for Mass. and RI) Roughly another 20% below Core Criteria 2.8 HVAC 46 23

24 3.3 Enhanced Performance LPD Values HVAC Plug Loads/Appliance Efficiency All appliances and equipment must meet Energy Star requirements Include control of plug loads in controls design as possible 48 24

25 3.11 Demand Responsive Buildings Reduce Peak Power Demand Identify and control at least a 10% interruptible load in the building Provide an interface to the utility capable of responding to real-time signals How to Pursue? Third-party aggregators now providing turnkey service Aggregators provide fixed annual payments plus payment-per- event called by ISO-NE Additional Commissioning Use of a credentialed third party commissioning (Cx) agent Cx Agent verifies construction drawings will satisfy Advanced Building Core Criteria and any Enhanced Criteria elected Cx Agent writes a report documenting results of Cx

26 Development of Vermont Core Performance 51 Questions to Answer How does the Core Performance program apply to typical Vermont construction? How does the Core Performance program compare relative to the Vermont energy code? Can Efficiency Vermont develop rule of thumb savings and cost estimates to streamline the program? 52 26

27 Evaluation Process Modeling and cost estimating Check cost-effectiveness of each component Modify Vermont Core Performance package, if necessary Propose savings and cost rules of thumb 53 Modeling First rule All Core Performance measures must improve upon code Building construction Metal frame wall and roof Metal frame windows Building types Office, school retail Building sizes For office, test from 20,000 to 70,000 ft

28 Modeling, cont. Four office mechanical systems Package VAV with water coils Single zone DX with hot water baseboard Single zone DX with furnace Water loop heat pump One school mechanical system Unit ventilators and package units One retail mechanical system Single zone DX with furnace 55 Estimating Costs Compare baseline (Vermont Code) systems versus Core Performance Primary, secondary sources Typical incremental costs Good averages across all projects; inappropriate for any single project 56 28

29 Check Cost-Effectiveness Most components of package provide greater benefits than costs Electric savings from Improved glazing Cooling equipment Lighting power density Lighting controls Some components do not pass Wall and roof insulation Demand-controlled ventilation for VAV Adjust Core Performance package 57 Modeling Results (Proposed) Electric Savings per ft 2 (Office) PVAV-HW SZRH PSZ-Furn WLHP Building Area (ft 2 ) School: 0.6 kwh/ft2; Retail: 2.1 kwh/ft

30 Modeling Results (Proposed) Natural Gas Savings per ft 2 (Office) PVAV-HW SZRH PSZ-Furn WLHP Building Area (ft 2 ) School: 0.09 therm/ft2; Retail: 0.24 therm/ft2 59 Energy Use Reductions Office School Retail Electricity 12% 10% 11% Fossil 29% 27% 46% 60 30

31 Incremental Cost Results (Proposed) $2.50 Cost per ft 2 (Office) PVAV-HW SZRH PSZ-Furn WLHP $2.00 $1.50 $1.00 $0.50 $ Building Area (ft 2 ) School: $2.10/ft2; Retail: $2.20/ft2 61 Cooling/Heating Capacity Reduction Office School Retail Cooling 5% - 13% 10% 16% Heating 12% Avg., (Wide range) 14% 33% Sizing benefits not factored into cost estimates 62 31

32 Enhanced Measures, Enhanced Savings (Preliminary) Daylighting Controls - Electric Savings per ft 2 (Office) PVAV-HW SZRH Enhanced LPD - Electric Savings per ft 2 (Office) PVAV-HW SZRH PSZ-Furn WLHP PSZ-Furn WLHP Electric Savings (kwh/ft 2 ) Building Area (ft 2 ) Electric Savings (kwh/ft 2 ) Building Area (ft 2 ) At lower costs than the Core Package (i.e., less than $2 per ft2) 63 Sample Cashflow (Based on Modeling) Project Name: Customer Name Project Cashflow Project Number: 32,000 ft2 Office Building with Proposed Costs, Results Project Economics: Investment Analysis: Inflation Rate: 3.61% Internal Rate of Return: n/ a Real Discount Rate: 6.8% Simple Payback (years): 6.7 Electricity Escalation Rate: 0% Net Present Value: $51,424 Annual Energy Savings: 1st Yr Electric Savings: $7,323 Loan Term (mont hs): 84 kwh: 52,680 Interest Rate: 6% kw Reduction: 0 Net Average Monthly Payment : $470 1st Yr Fossil Fuel Savings: $2,050 Annual Annual Payment s Annual Fuel (Principal & Elect ric Savings/ Net Annual Net Cumulat ive Year Int erest ) Savings (Cost s) Cashflow Cashflow 0 $21,459 $21,459 1 ($12,562) $7,323 $2,050 ($3,189) $18,270 2 ($12,562) $7,587 $2,124 ($2,851) $15,419 3 ($12,562) $7,861 $2,201 ($2,501) $12,918 4 ($12,562) $8,145 $2,280 ($2,137) $10,781 5 ($12,562) $8,439 $2,362 ($1,761) $9,020 6 ($12,562) $8,743 $2,448 ($1,371) $7,649 7 ($12,562) $9,059 $2,536 ($967) $6,682 8 $0 $9,386 $2,628 $12,013 $18,695 9 $0 $9,725 $2,722 $12,447 $31, $0 $10,076 $2,821 $12,896 $44, $0 $10,439 $2,923 $13,362 $57, $0 $10,816 $3,028 $13,844 $71, $0 $11,207 $3,137 $14,344 $85, $0 $11,611 $3,251 $14,862 $100,451 Note: cost estimates relative to savings are likely conservative 64 32

33 How Will Efficiency Vermont Work with Design Teams? 65 Efficiency Vermont Tracks Prescriptive Track Buildings <10,000 square feet Measures listed on prescriptive forms (AC/motors/lighting) Core Performance Track Retail, School or Office Buildings >10,000 square feet Meet Core Performance Credits Additional incentives available for Enhanced measures Custom Track Buildings >10,000 square feet that don t meet Core Performance criteria Projects < 10,000 sq ft that have measures not listed on the prescriptive forms

34 67 Efficiency Vermont Incentives Design Strategies (Section 1) $0.10 per ft2 to meet Sections 1.1 through 1.6 $2,500 per project for meeting Section 1.7 Core Performance Package (Section 2): $0.50 per ft2 Enhanced Measures (Section 3): LPD - $1 per W per ft2 improvement from the Core package Daylighting custom Other measures - custom 68 34

35 Working through Core Performance with Efficiency Vermont Plan Ahead Based upon your review of the Credits, prepare your own strategy for meeting the intent of each credit, particularly in Section 1. For qualitative credits, identify those elements of the scope of work with which you have issues, and how to address them (as you would for any RFP) Meet with Efficiency Vermont Staff Have an open discussion about the issues associated with compliance Enter into a collaborative process to focus on the objective high-performance design with high-efficiency equipment and a process to ensure proper operation Keep Open Lines of Communication Consider Efficiency Vermont staff as allies Identify what you need 69 Questions? 70 35