Control Strategies Affected by Changes to 90.1

Transcription

1 Click to edit Master title style AGENDA Motivations behind changes Control Strategies Affected by Changes to 90.1 Mechanical Related Controls - Water side - Good Practices page 2 ASHE Engages Energy Policy History of Commercial Building Energy Codes Advocacy Office in Washington, DC Works with Organizations USGBC, BOMA, IES, AIA, etc. Code Adoption SSPC 90.1 [New Buildings] SSPC [High-Performance] SSPC 100 [Existing Buildings] All in code written language. Year Revision Year Energy Efficiency Description ,000 BTU/Sq.ft/Year National Energy Conservation Policy Act (NECPA) Energy Policy Act mandates all states must review/consider adopting the national model energy standard (ASHE ) ,300 BTU/Sq.ft/Year 1992 Energy Policy Act requires States energy codes to meet/exceed ASHE by July 15, ,000 BTU/Sq.ft/Year Energy Policy Act of 2005 mandated all states must review/consider adopting national model energy standard (ASHE ) ,000 BTU/Sq.ft/Year American Clean Energy & Security Act of 2009 (ACES) National Energy Code ,300 BTU/Sq.ft/Year American Recovery & Reinvestment Act of 2009 (AR) Requires IECC as code; 11% below ASHE ,000 BTU/Sq.ft/Year IECC updated; 30% energy savings over States adopt no later than December ,500 BTU/Sq.ft/Year 50% energy savings over (Goal) page 3 Oct page page 4 1

2 Green Building Codes Progress Toward Sustainability Illinois Energy Conservation Code for Commercial Buildings became effective 2006 Energy Efficiency Building Act New Code incorporates IECC References ASHE State requires new versions of IECC to be adopted within 1 year IECC updated in References ASHE Who s involved: AIA, ASTM, ASHE, USGBC, IES Information is drawn from the U.S. Department of Energy s (DOE) Building Energy Codes Program and the Building Codes Assistance Project (BP) page 5 page 6 SSPC 90.1 Energy Efficient Design of Commercial Buildings Target: New Buildings 2010 Edition, due January % more energy efficient than 2004 edition Over 100 Approved Addendums Controls mentioned 67 times 2013 Edition, the Challenge 50% more energy efficient than 2004 edition. SSPC 100 Energy Efficient Existing Buildings Target: Existing Buildings [Under Development] Purpose: Energy efficient exiting buildings Provide procedures and programs towards energy efficient operation, maintenance, management and monitoring; Increase energy efficiency of energy-using systems and components; and Upgrading thermal performance of the building envelope. page 7 page 8/23 2

3 STANDARD YS Equipment Efficiency Ratings changed from SEER to IEER - Recognizes part load performance - Covers a variety of terminal units Heat pumps Fan Coils VRF Rooftops -Decoupled cooling components - Packaged cooling terminal units VRF and HPs - More points to monitor - More smart terminal units = more integration and less single source controls - Less pure systems - AHUs driven by Vent loads not design cooling loads All AC equipment with water cooled condensers must have a control valve that can stop the flow when cooling is not needed (C ) More Control Valves Coordinate pumps with 0% call for cooling Promotes variable pumping systems with controls Part load efficiency means part load sensing + part load outputs which means smarter controls. page 9 page 10 STANDARD YS Added Water-to-Water HPs Machine efficiency requirement determined by heat rejection method Added VRF Systems Recognizes condenser heat recovery methods -More options for engineers to reject heat - More options to move away from pure systems - More options for using water source heat rejection - More options for synergy between heating and cooling Fan speed reduction required on small packaged AHUs - Tons >9.2 at loads less than 50% - 2 speed or variable fan speed More complex packaged units More smart rooftops integration to BAS is good practice If serving a DCV zone, then more control loops and variable vent page 11 page 12 3

4 Fan speed reduction required on CHW AHUs - fan motor > 5 hp - 2 speed or variable fan speed Zone 4a and 5a Energy Recovery Ventilation Requirements Table Exhaust Air Energy recovery Requirements Fan speed controls Variable ventilation positions Compensation for building pressure balancing Discharge temperature sensors If DCV zones, then I monitoring required More controls points on smaller systems Was 15 hp in % Outdoor Air at Full Design Airflow Rate Climate Zone 30-40% 40-50% 50-60% 60-70% 70-80% > 80% Design Supply Fan Airflow Rate (cfm) 3bc,4bc,5, b NR NR NR NR b,2b,5c NR NR b a-6a >0 7, >0 >0 >0 >0 page 13 page 14 More control points Coordinate with Economizer Bypass for economizer means motorized isolation dampers Exceptions for labs, warehouses, solar heat, distributed exhaust VFDs on unitary water pumps p > 5 hp VFDs on all other system water pumps > 10hp (Down from 50hp) -VFDs on almost all pumps - More points to monitor - Sensor to control pump - More control loops - More communication points page 15 page 16 4

5 Chiller Part Load Efficiency metric to meet (Addendum M) Chiller Part Loads Part II - 80% of chiller operation spent at less than 50% load - Sequencing chiller more complex - Whole system optimization should take into account system loads, pump speeds, tower approach, etc. - Chiller efficiency taken before compressor VFD means less attractive to put VFD on compressor Water distribution improvements: Flatten system flow curve for more better turn down Better matching of control valves to coils to raise coil T More modulating control valves to reduce spikes Temperature reset strategies to keep coils in sweet spots Flow modulation to keep T high More variable primary flow systems page 17 page 18 Data STANDARD Center Additions YS Adds CC units to scope of standard (Addendum Aq) Adds efficiency requirements for computer rooms (Addendum Bu) New requirements when using water and air side economizers Data Center Exceptions Lists exceptions for economizers Data Center modeling is not available in 90.1 Alternative to modeling is power usage effectiveness (PUE) Significant additions to come in future additions to the standard. page 19 page 20 5

6 Water side Water side Requires service water booster pumps p to be controls by VFDs -Eliminates PRVs on domestic water - Adds VFDs, sensors, control loops - More points to monitor - More critical alarms Packaged racks of pumps with controls are common solution. Opportunity for integration to BAS for single source operation. page 21 Isolation valves on systems with multiple chillers or boilers Reduces bypass mixing inefficiencies Improves coil efficiencies Reduces pumping energy Isolation valves added to water loops Need to interlock to equipment Need safety to make sure equipment is not run with no flow Need safety to pumps to make sure not deadheaded Valve sizing more critical Pressure independent valves less attractive page 22 Water side Water side Pump pressure optimization Variable speed pumping over 10hp Pressure sensors to maintain pressure at extreme locations Poll valves to adjust pressure setpoint such that 1 valve is near 100% open Requires a BAS system Temperature Control Reset above 300,000 BTU/h (C ) Effect on Co ontrols Hot water systems traditional resets Effect on Co ontrols Chiller systems look at zone or return loads Require BAS control Tight constraints Move slow page 23 page 24 6

7 Economizers required for systems > 33,000 BTU/h (3 tons) (C ) More strict than 90.1 Motorized and Low Leakage Dampers at outdoor barriers (C402452) (C ) Must be sequenced with the mechanical cooling, not mixed air Must be sized to match max design supply airflow May be needed for zone heat pumps bolt on strategy Water coil economizers can be substituted Exceptions including heat recovery Must operate with ventilation schedules Includes stairways and shafts (fail open) 4 cfm/ft 2 at10inwg 1.0 in.wg Exception for 1 and 2 story buildings and less than 300 cfm page 25 page 26 STANDARD YS required on more special applications: Hospital applications Labs Requires more heat recovery Removed blanket exception for labs and pressurization Many details covered by other standards. Effects on Controls Significantly increases complexity of lab controls Requires hoods Requires pressurization controls Requires MUA units page 27 Effect on Controls Supply Air Temperature Reset Multizone shall automatically raise the supply air temperature when the s served are not at peak loads Infers BAS that can monitor zone statuses as input to the setpoint control Goal is to decrease cooling load, reduce reheat, increase economizer usage Tight constraints - setpoints between 50 and 60F Suspended for dehumidify control page 28 7

8 Demand Control Ventilation for s above 25 people p per 1000 ft 2 man Demand Control Ventilation for s above 25 people p per 1000 ft 2 man Zone Level Demand Control Population count Box position reset can be used with formulas Single Zone AHU Demand Control can be at AHU Population count Formulas reset I cfm page 29 page 30 Demand Control Ventilation for s above 25 people p per 1000 ft 2 man Demand Control Ventilation for s above 25 people p per 1000 ft 2 man 600 System INtake Airflow (Vot), cfm Set position of damper to bring in Vot-design when indoor equals Cs-design When indoor is between Cs-min and Csdesign, adjust damper proportionally 300 bt between Vot-min V and dvot-design Set position of damper to bring in Vot-min when indoor air equals Cs-min Multi Zone DCV at Ventilation Optimization based on population count Ventilation reset because of fan speed Measured Space Concentration (Cs), ppm page 31 page 32 8

9 Demand Control Ventilation for s above 25 people p per 1000 ft 2 man Demand Control Ventilation for s above 25 people p per 1000 ft 2 man Multi Zone Mixed Air DCV at Population count all zones Ventilation Optimization based on population count Ventilation reset because of fan speed Formulas to take credit for some zones over-ventilated page 33 Dedicated Outdoor Air -Simple Constant flow to all zones 2 position on-off ventilation for high occupancy zones page 34 DS Fan VFD Demand Control Ventilation for s above 25 people p per 1000 ft 2 man No simultaneous heating and cooling 20F max reheat above zone setpoint Dedicated Outdoor Air -Advanced Population count from all zones Pressure independent es serving all zones If terminal units are variable fan speed, then PI es are needed DS Fan VFD Reduce minimums as low as Dual max DDC controls is new standard possible Reset will help DCV can reduce minimums in some s DDC es can control to 10:1 turndown compared to 5:1 Encourages separate htg source page 35 page 36 9

10 ASHE Lighting Changes CO sensors and control panels 2-speed or VFD fans for 50% reduction Requires 2-stage ventilation for enclosed garages Suggestion: Adding to BAS for monitoring is cheap adder Revised/Interior LPDs (efficiency, geometry) Exterior LPD requirements expansion Detailed daylighting control and skylight requirements Occupancy Sensor Control (more s, vacancy) Exterior Lighting Control (after-hours requirements) Parking Garage Lighting Control (daylighting & afterhours) Emergency (night light) shut-off and Stairwell control Control incentives for advanced controls Guest bathroom lighting control Receptacle shut-off control (50% auto-off) Functional Testing (Commissioning) Lighting Controls page 37 page 38 ASHE Receptacle Shutoff (50% Auto-off) How Do We Get to Goal? Interoperability Requires 50% of receptacles (wall plugs) in a to have automatic shutoff control. Applies to 125 volt (15-20 amp) receptacles in Private Offices, Open Offices and Computer Classrooms. Requires automatic control using Time of Day Scheduling Occupancy Sensor or, Other automatic control based on occupancy page 39 page 40 10

11 How Do We Get to Goal? ASHE Advanced Energy Design Guides How Do We Get To Goal? Just Do It Migrate to more energy efficient HVAC and Lighting technologies Light Commercial Building Market Fastest growing building market segment Small Office Buildings building with total floor area of 20, ft 2, Daylight harvesting with Interior Lighting Controls Packaged rooftop or split system heat pumps serving each zone. Ventilation provided by Dedicated Outside Air System (DS). DS system with Energy Recovery Ventilation (ERV) Medium Office Buildings Three-story building with total floor area of 53,600 ft 2, Daylight harvesting and occupancy based controls. DS with Heat Recovery Radiant Systems (Heating & Cooling) page 41 Designing for Part Load Efficiency Synergies Heat Reclaim Coordinating lights with HVAC Plant equipment reset from zone control Load Matching Systems New Technologies Mixed-Mode Ventilation Automated Operable Windows Blind Controls Building Façades Load Matching Systems Renewable Energy page 42 Best Practices Questions 1. For every decision, ask What is impact on energy. 2. Embrace resetting strategies like population counting and setpoint optimizations 3. Automate system reactions to leave operators to handle only exceptions or problems. 4. Use Energy Management Software for info use Automation for control. page 43 page 44 11