A S H R A E To p i c s T i t l e 2 4 F i r s t S t a ke h o l d e r M e e t i n g

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1 A S H R A E To p i c s T i t l e 2 4 F i r s t S t a ke h o l d e r M e e t i n g Introduction May 10, 2010 San Ramon Conference Center This memo summarizes the key discussions that were held during the first Investor Owned Utility (IOU) sponsored 2011 Title 24 stakeholder meeting for ASHRAE 90.1 related topics. The meeting was held at the San Ramon Conference Center May 10 th Most of the discussions focused on the specific code change options presented and the proposed methods of analysis or presentation of data. For a full understanding of the scope of each code change proposal, this memo should be read in conjunction with the power point materials that were presented at the stakeholder meeting. 1. Attendee / Call List PG&E - Stuart Tartaglia, Gaye Powell, Charlene Spoor, Keith Forsman, Judith Jennings, Sherry Hu Food Service Technology Center - Don Fisher CEC - Mark Alatorre, Seran Thamilseran, Ron Yasny, Joe Loyer Taylor Engineering - Jeff Stein, Mark Hydeman, Todd Goshell, Rupam Singla Sempra Utilities - Ron Gorman SCE - Randall Higa Trane - James Poole, Lee Burgett Carrier Corp - Richard Lord, Jim Pegues Emerson - Hung Pham AirTest - Mike Schell Nagle Energy Solutions - Frank Nagle Atlas Project Support - Michael Vargas Energy Solutions for PG&E - Michael McGaraghan, Elizabeth Joyce 2. TOPICS DISCUSSED 2.1 CHILLER EFFICIENCY

2 Overview: This measure seeks to copy recent changes to chiller efficiency in ASHRAE Addendum M, changes to chiller operating conditions, and a new equation for nonstandard chillers. This measure may copy parts or all of the most recent ASHRAE changes; it may adopt both a new k-factor (nonstandard) equation, and a wider range of operating conditions (for any of the paths chosen for chillers). Jeff Stein: It is difficult to collect reliable incremental cost data on chillers; Taylor is asking stakeholders for any data they might have. Taylor has first costs data from AHRI. Other potential costs include: higher or lower electrical service costs from lesser/greater efficiency, incidental structural or mechanical costs, etc. Initial results show that Path A is less expensive than Path B, and has lower incremental costs. Question, Discussions: Hung Pham: Why is Path B not available for air-cooled chillers? Jeff Stein: The data was provided by manufacturers; the ASHRAE change for air-cooled chillers was almost entirely on part-load efficiency, so Path B is less relevant. Mark Hydeman: As part-load efficiencies became more aggressive, machines with variable speed drives (VSDs) experienced penalties at full load. Dick Lord: AHRI is now discussing a Path B for air-cooled chillers, possibly put into with an effective date of Dick Lord: There is some wording in 90.1 about adding glycol for freeze protection should include this in the Title 24 proposal. Dick Lord: ASHRAE justified the life cycle costs (LCC) of this measure by using ASHRAE rates, but Taylor will have to use CA time dependant valuation (TDV) rates. 2.2 COOLING TOWERS Overview: Changes to cooling towers include consideration of VSDs for smaller towers, include requirements for closed circuit fluid coolers; and provide a prescriptive minimum approach for a variety of types. Currently, Title 24 requirements mirror ASHRAE , which are outdated. This measure will address all nonresidential applications, not just process loads. Mark Hydeman: A better definition of poor water quality is necessary, for aircooled chillers exceptions (air-cooled chillers are allowed as equivalent in certain circumstances such as poor water quality). Jim Poole: Would the efficiency still be a GPM (gallons per minute) per HP (horsepower) metric? Mark Hydeman: Yes, and the same test conditions would remain; 95 o F condensor water return, 85 o F condenser water supply, 75 o F wetbulb.

3 Dick Lord: CCA 6 has been working on an approach equation for the minimum approach tables. This might be a starting point for approach criteria; talk to Frank Morrison. 2.3 SMALL ECM (ELECTRONICALLY COMMUTATED) MOTORS Overview: Propose changing certain CA standards from requiring ECM motors, to instead a general performance requirement. Or, the opposite proposal: require ECM motors everywhere on HVAC duty (but not packaged units), with some exceptions. Mark Hydeman: This code change may be more relevant to Title 20 (1605.1(s)). Seran Thamileran: EISA is going to cover multipole and original equipment manufacture (OEM) motors separately, effective in December Mark Hydeman: Taylor needs incremental cost data for ECM motors. Don Fisher: Is there another type of motor not being mentioned here? Mark Hydeman: there is CSCR (capacitor start, capacitor run), CSIR (capacitor start, induction run), polyphase; these are federally covered. Sherry Hu: What about categories of motors in furnaces, and typical test procedures? Mark Hydeman: Furnaces are exempt. NAECA (National Appliance Energy Conservation Act) pre-exempted states from having stricter standards than DOE; however, efficiency advocates (including California utilities) supported stricter standards in the last DOE rulemaking. Dick Lord: Will the standards be performance or prescriptive? Mark Hydeman: The CEC prefers performance-oriented, to avoid complexity. Dick Lord: Agrees, given some new technologies, it s important to support a component approach. Mike McGaraghan: Are there specific efficient newer motors that might not be ECM, but should still be included or covered in standards language? Dick Lord: Novatech motors check with Mark Madera at Western Cooling Technology. Mike McGaraghan: For the energy modeling analysis, what operating patterns will be assumed, where will you get load schedules to quantify these uses? Mark Hydeman: If the motor is likely to be controlled by controls, measurement will be done in-field. If the motor is on a schedule, then Taylor will go to ASHRAE 90.1 or DOE for sources. The Pacific Northwest National Lab has use models also. 2.4 KITCHEN VENTILATION Overview: Proposing changes to T24 based off of imminent ASHRAE There are six proposals:

4 Proposal 1 Scope and Definitions: Remove process exception, add definitions based on ASHRAE 154. Proposal 2 Limit direct replacement air to 10% of exhaust airflow (no Short Circuit Hoods). Proposal 3 Limit use of outside air (OA) as replacement air, as much as possible, when transfer air is available. Proposal 4 Limit excessive exhaust amount for hoods in a kitchen that has airflow > 5000 cfm. Allows use of transfer air and effectively outlaws use of unlisted hoods (Table 4, ASHRAE 154). Proposal 5 Allows four mix-and-match compliance options (use of transfer air, demand controlled ventilation (DCV) with temperature or CO 2 sensors, energy recovery device, limited mechanical cooling), such that A+B+C+D > 80%. Proposal 6 Field test (acceptance test) requirement. The current proposal is not very specific, but is intended to open up the general idea of a test now, and require details later. No analysis is planned for this measure. Jeff Stein: ASHRAE is unclear about replacement air (proposal 3); it says says you can use up to 100% outside air as replacement air. Mark Hydeman: There are concerns for pushing Proposal 5 past CAL OSHA. Don Fisher: There s already a safety factor of about 20% put into the typical hood, so taking out that 20% via this proposal will just take out that over-engineered safety factor. Don Fisher: Makeup air and replacement air are the same thing (Proposal 1) the term makeup air should no longer be used. Jeff Stein: Short circuit hoods are only used on about 1% of kitchen systems in CA now, though represent about 20% of U.S. usage (Proposal 2). Stuart Tartaglia: Why the discrepancy? Don Fisher: We ve been opposing it in CA for years, as bad practice. Don Fisher: Typical practice won t allow the use 80% transfer air (proposal 3); it should be more like 50-60%. Todd Goshell: There s an exception in 90.1 we must leave the door open to use OA even in cases where 100% transfer air can supply the air requirements. Stuart Tartaglia: The list of listed hoods (Proposal 4) where is it? Jeff Stein: UL (Underwriters Laboratories) does the listing (UL 1710 standard), it should be printed on the hood itself. Don Fisher: A temperature control probe can t set up to go below 80% flow (Proposal 5), expect some pushback on this. It would not be easily met at a 50% reduction requirement, and is expensive to implement; feasible at a 20% reduction. Mark Hydeman: Could add a multiplier to that option in the compliance equation. Don Fisher: There may be serious objection given the real design and cost problem; for example, you can t use A (use of transfer) on its own to reach 80%, it s too

5 expensive / prohibitive. Todd Goshell: It may be possible to reduce the overall 80% requirement, instead. 2.5 GARAGE CO DEMAND CONTROLLED VENTILATION (DCV) Overview: DCV is not currently allowed in CA T24; ASHRAE 90.1 has a current proposal to require it except in large unconditioned garages. Most new garages do have DCV systems with CO sensor, even though code is not explicit, though existing garages have arbitrary fan schedules. This proposal may also require some sort of acceptance testing. Jeff Stein: We need to distinguish the CO sensors from the assumptions about CO 2 sensors (there has been recent research on the poor accuracy of CO 2 sensors). Mike Schell: Has done research on CO sensors, saw only ~5% drift over 1 year, can verify their good performance. Jeff Stein: Taylor wants to do a field study of CO sensor accuracy, third-party testing of facilities Taylor has already been involved in. Frank Nagle: Can provide cost data to assist Taylor in this effort. Mike Schell: Has found that with VFDs, if the fan speed is set to the baseline, one can build up a bank of fresh air within the building and there s no real need to ramp up speed during CO events. This gives demand-side (peak operation) benefits. Mike Schell: What kind of area coverage is recommended for sensors? The rule of thumb is one per ft 2 ; it will be necessary to provide a recommendation for sensor coverage. Jeff Stein: That seems like a mechanical code issue. Jeff worries about inconsistency between T24 and mechanical code if implemented separately. Seran Thamilseran: The location of the sensor is also key, almost more important than how much square footage they cover. Frank Nagle: How does this cross over into real-world applications? His experience is that the payback period for CO DCV extends out to 8+ years, which isn t attractive to a property owner. 2.6 VARIABLE AIR VOLUME (VAV) LABORATORY AND FUME EXHAUST Overview: Current practice is treating laboratory exhaust as a process, with little thought to energy use and human comfort issues. This proposal removes process exception for laboratories; may include limitations on fan power, requirements for VAV exhaust or heat recovery, or demand-controlled supply temperature/pressure. In Taylor retrofits on labs from constant volume to VAV systems, Taylor havs seen 50%+ energy reductions with 4-8 year paybacks. Mark Hydeman: The current definition of process loads, excluded from T24, may exclude lab exhaust. The main issue is that lab ventilation currently doesn t have to

6 deal with human comfort, covers issues of toxicity and flammability. ASHRAE 90.1 got rid of this exception for process loads in Addendum AQ; need to do the same thing for T24. Mark Hydeman: There are concerns over changing hood sash movement speed, for example if it used an automatic sensor. CalOSHA recently requires that if the sash speed is changed, need to retest the hood under ASHRAE test method, which uses sulfur hexafluoride (which has extremely high GWP). CalOSHA is reconsidering this test. Don Fisher: Have you looked at rotary wheel heat exchangers? Mark: Not yet. Additional Information and Links Additional information can be found at the Title 24 Codes and Standards Enhancement (CASE) website,