Process Air Compressors, Boilers, and Water Heaters Stakeholder Meeting 2

Transcription

1 Process Air Compressors, Boilers, and Water Heaters Stakeholder Meeting 2 California Statewide Utility Codes and Standards Program Energy Solutions Heschong Mahone Group, Inc. Portland Energy Conservation, Inc. Taylor Engineering

2 Air Compressors Stakeholder Meeting 2 California Statewide Utility Codes and Standards Program Energy Solutions

3 3 Air Compressors Summary of current code requirements Compressed Air energy use Potential new code proposals Baseline Systems Cost Effectiveness Methodology Next Steps Specific stakeholder requests

4 4 Air Compressors Current Code Requirements Title 24 Most Process loads, including compressed air systems, are not currently covered in Title Process loads are defined by Title 24 as: an activity or treatment that is not related to the space conditioning, lighting, service water heating or ventilating of a building as it relates to human occupancy Refrigerated warehouses are covered as a process load

5 Air Compressors Why Compressed Air? CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 5 Material Process 23% Material Handling 12% Other 4% Compressed Air 16% Pump 24% Motor System Energy Use per Application (source: Motor Systems Opportunities Market Assessment, 2002 EERE) Refrigeration 7% Fan 14% 16 % of U.S. industrial motor systems energy in 10% of total industrial energy use ~90,000 GWh annual consumption

6 Air Compressors Why Compressed Air? CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 6 With cost-effective measures, savings can be upwards of 17% or more (~15,000 GWh) Measures with <3yr payback Source: Assessment of the Market for Compressed Air Efficiency Services, EERE 2001

7 Air Compressors Potential Code Change Proposals 7 Potential code change proposals in May: Performance metric or set of system design guidelines for compressed air systems Requirements for smart system controls on multicompressor systems To arrive at a final proposal: Surveyed all potential measures Narrowed down to 2 potential measures Looking for something simple

8 Air Compressors Potential New Code Proposals 8 Requirements for a Variable Speed Drive (VSD) as the designated trim compressor on all compressed air systems Requirements for smart system controls on multi-compressor systems Possible cost-effective system size threshold Focusing on: New Construction and Major Renovations Permanent installations

9 Air Compressors Potential New Code Proposals 9 VSD for trim load Trim compressor works at part-load majority of time Constant-speed machines work best at full-load VSDs work best at part-load (and thus, as a trim compressor) Common recommendation for energy efficiency Widely available!

10 10 Air Compressors Potential New Code Proposals Smart system controls save energy by: choosing the ideal combination of compressors avoiding part-load on more than one compressor Minimum Requirements: Able to turn on and turn off compressors based on current demand (as measured at a common header) Able to designate a trim compressor Able to control compressors of different types and for more than one manufacturer There are about a dozen companies that currently offer these kinds of controls

11 Air Compressors Potential New Code Proposals 11 Smart controls have a variety of other benefits: Data logging Improved maintenance Improved System performance Improved productivity Variety of inputs to improve performance (even weather data) Ease of expansion Savings can be upwards of 10% of energy use One 2-compressor project saved ~93,000 kwh with smart controls

12 Air Compressors Initial Data / Findings CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 12 GOAL: Determine if the measures are costeffective Energy savings is worth the incremental cost What are the energy savings? What are we comparing these measures against? No prior code requirements Energy savings are based on typical practice Next Step: Determine a baseline

13 Air Compressors Baselines - Initial Data / Findings 13 Is there a typical system? The market is varied with unique needs for Compressed Air Assessments in CA unique industries (Source: DOE IAC Database) Includes: Food Rubber Mfg Metal Paper Electronics # of Assessments Transportation Machinery Electronics Paper Primary Metal Fabricated Rubber Food

14 Air Compressors Baselines - Initial Data / Findings 14 Complex systems with many factors Demand Pressure, Flow, Variability Supply Compressor count/types/sizes, Controls Conditioning Moisture, Particulates, Other Contaminants A typical system does not exist New Plan Capture majority of market with representative systems Receive feedback from industry Model in AirMaster+

15 Air Compressors Baseline Case #1 High Tech Co. 15 A very large high tech manufacturing facility with very stringent needs for air conditioning (moisture level, particulates, volatile compounds, etc.) Large, relatively constant air demand cfm avg. for psi

16 Air Compressors Baseline Case #2 Seasonal LLC 16 Medium sized food processing plant with two modes of operation: high demand during the harvest season and low demand during the rest of the year. Demand is relatively flat on a moment-tomoment basis within those two seasons. 250 cfm avg. for psi 75 cfm avg. for psi

17 Air Compressors More Baselines CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 17 Plastic packaging factory (medium fluctuating demand) Small local machine shop (low fluctuating demand). Small textiles plant (small constant demand) Several possible implementations of each of these (different compressor types and configurations).

18 Air Compressors Methodology for Cost Effectiveness 18 Modeling Savings Incremental Costs Cost Effectiveness

19 Air Compressors Methodology: Modeling Savings 19 Working with Eric Bessey Model each baseline in AirMaster+ Apply 2 code proposals VFD: Replace trim compressor with VFD Smart Controls: Manually choose best combination of compressors per hour Compare energy use to determine annual savings Focus on conservative cases

20 Air Compressors Methodology: Incremental Costs 20 VSDs $ / hp Costs based on Equipment Installation Source New construction and retrofit projects Smart Controls $300 - $1500 per collection point Example: $15,000 total cost for upgrading a 2- compressor system (~1 yr payback) Costs based on Equipment Installation Sources Compressed Air Challenge Retrofit project

21 Air Compressors Methodology: Cost Effectiveness 21 ΔLCC = Cost Premium Present Value of Energy Savings Cost Premium = Incremental Costs Present Value = Energy Savings, weighted with societal benefit (TDV) and converted to $. If ΔLCC is negative, measure is costeffective Present Value Hourly multiplier (TDV) is applied to hourly savings (as modeled by AirMaster+)

22 Air Compressors Next Steps CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 22 Incorporate feedback from industry to finalize baselines Model baseline systems in AirMaster+ Refine incremental costs Formalize specific code language

23 Air Compressors Specific Stakeholder Requests 23 Send feedback on: Baseline systems New code proposals Methodology for energy savings Sources for incremental costs Information on industrial compliance

24 24 QUESTIONS & COMMENTS Russell Torres x269 Ransom Byers x214

25 Air Compressors: Appendix California Statewide Utility Codes and Standards Program

26 Air Compressors Why AirMaster+? CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 26 Consider the following: Universal tool Impartial Used in previous efficiency assessments Can be modified Known assumptions: Component location not considered Secondary storage not modeled

27 Air Compressors Compressed Air by Sector CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 27 Annual Electricity Consumption for Compressed Air (by sector) % of Total Electricity Use for Compressed Air (by sector)

28 28 Hot Water Temperature Reset Controls: Stakeholder Meeting 2 California Statewide Utility Codes and Standards Program PECI

29 Chilled and Hot Water Temperature Reset Controls Current Code Requirements and Proposed Change gray [delete] /underline [add] (j)1: HVAC chilled and hot water pumping shall be designed for variable fluid flow Chilled and Hot Water Temperature Reset Controls. Chilled and hot water systems with a design capacity exceeding 500,000 Btu/hr supplying chilled or heated water (or both) shall include controls that automatically reset supply water temperatures as a function of representative building loads or outside air temperature. EXCEPTION to Section 144(j)4: Hydronic Chilled water systems that use variable flow speed drives to reduce pumping energy in accordance with Section 144(j)1 144(j)6. 144(j)6: CHW pumps over 5HP shall have VFDs the pressure shall be reset by valve position. CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes

30 30 Chilled and Hot Water Temperature Reset Controls History The CHW/HW temperature reset controls have been in Title 24 since 2005 The same requirements are in ASHRAE CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes

31 31 Chilled and Hot Water Temperature Reset Controls Rationale Hot Water HW temperature reset always reduces boiler energy and piping losses and always reduces total energy, especially for condensing boilers HW temperature reset can increase HW pump energy if the pump has a VFD. (VFDs are not cost effective or required on hot water pumps). Even if the HW pump has a VFD, increasing HW pump energy decreases boiler energy (opposite of CHW pumps!) so HWST reset always makes sense Temperature reset is low/no cost it requres a minor amount of programming but no additional hardware CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes

32 32 Chilled and Hot Water Temperature Reset Controls Rationale Chilled Water Variable flow is required on most CHW and HW systems VFDs are required on many CHW pumps but not on any HW pumps For CHW systems with VFDs the options are to reset pressure setpoint and/or temperature setpoint Resetting pressure will always reduce total energy but will not necessarily save as much energy as temperature reset The converse is not necessarily true: resetting temperature could increase total energy in some scenarios. This is why pressure reset is required but temperature reset is not required. For CHW systems without VFDs there is no pressure reset Resetting the temperature will result in a tiny increase in pump energy for variable flow systems (pump rides out on curve) but will always reduce total energy due to reduced chiller lift The CHW exeption for variable flow was likely a mistake caused by 90.1 language that lumps variable flow and variable speed in the same section CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes

33 33 Chilled and Hot Water Temperature Reset Controls Future CHW Reset Changes? Our recent analyses show that CHW temperature reset saves more than pressure reset unless the pump head is unusually high Temperature reset is particularly important for waterside economizers We may want to: Always require temperature reset and require pressure reset for high pump head Always require both (like air handlers) The users guide should discuss combined sequences CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes

34 34 QUESTIONS & COMMENTS Jeff Stein

35 35 Process Boilers: Stakeholder Meeting 2 California Statewide Utility Codes and Standards Program PECI

36 Process Boilers Current Requirements CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 36 Title 24 historically does not regulate processes Possible if also serves DHW or space heating

37 Process Boilers Code change options (mandatory) 37 Flue damper Electronic parallel positioning control Electronic parallel positioning with oxygen trim control Variable frequency drive on combustion air fan

38 Process Boilers Data collection and analysis CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 38 Determine effect of new air quality regulations on measures Determine energy savings spreadsheet calcs field monitoring and analysis Determine incremental measure costs

39 Process Boilers New air quality regulations CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 39 At least 3 air districts have recently adopted more stringent NOx regulations Bay Area 5-20 MMBtu/hr: 15 ppm (7/2008) MMBtu/hr: 9 ppm San Joaquin Valley 5-20 MMBtu/hr: 9/6 ppm (2012/2014) > 20 MMBtu/hr: 7/5 ppm (2010/2014) South Coast 5-75 MMBtu/hr: 9 ppm (1/2013)

40 Process Boilers New air quality regulations CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 40 At least 3 air districts have recently adopted more stringent NOx regulations Represent 75% of CA installations (payroll, # businesses as proxy) Driven by ozone standard non-attainment

41 41

42 42 California Nonattainment Area Classification: Ozone 1-hour Standard

43 43 Process Boilers Compliance methods for air quality regs Pay a fine instead of complying Replace the entire boiler Selective catalytic reduction Ultra low-nox burner Forced draft Parallel positioning controls

44 Process Boilers Estimate energy savings CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 44 Boiler permits for new installations and replacements NOx regs apply to specific ranges of boiler sizes knowing the sizes of the new boilers by year, then know the # installed by NOx level 20% boilers serve both a process + space heating/dhw load 71% boilers are low NOx or ultra low NOx burners and thus come with PP controls. The other 29% are candidates for the parallel positioning measure. 75% load factor 330 F stack temperature 6-7% O 2 setpoint for typical boiler installation 5% O 2 setpoint (PP)

45 45 Process Boilers Energy savings, per measure Marginal cost < NPV$ Payback period < yrs Per measure break-even savings estimate, site energy, non-tdv numbers Energy Savings (therms/yr) Cost Savings ($/yr) Cost Savings (NPV $, 11.9 yrs) Marginal Cost Payback, yrs Input MMBtu/h for break even Measure Flue Damper 69 $84 $1,000 $1, Parallel Positioning 618 $754 $9,002 $9, kwh/yr Motor HP Combustion Fan VFD 2,065 $330 $3,946 $3, Assumed Energy Costs Natural Gas Electricity $1.22 /therm $0.16 /kwh

46 46 Process Boilers Energy savings, statewide Statewide savings estimate, site energy, non-tdv numbers Energy Savings Estimate (therms/yr) Cost Savings Estimate ($/yr) Cost Savings Estimate (NPV $, 11.9 yrs) Measure Low High Low High Low High Flue Damper 4,667 42,352 $5,694 $51,669 $67,760 $614,862 Parallel Positioning 110, ,934 $134,626 $339,079 $1,602,046 $4,035,041 kwh/yr $/yr NPV $, 11.9 yrs Combustion Fan VFD 39,701 79,402 $6,352 $12,704 $75,590 $151,181 Assumed Energy Costs Natural Gas Electricity $1.22 /therm $0.16 /kwh

47 Process Boilers Parallel positioning plus O2 trim 47 Conducted onsite measurements at 2 sites: central plants at a university and a hospital Combustion efficiency is a function of stack O2, stack temp, and combustion air temp Take measurements with O2 trim enabled and disabled over range of firing rates

48 48 Process Boilers Parallel positioning plus O2 trim Both boilers were recently tuned Site 1 Site 2 Input, Btu/hr 28,577,000 29,660,000 Btu/hr per HP 33,446 33,446 Input, HP Output, Btu/hr 25,000,000 24,610,000 Output, HP Efficiency 87% 83% Type firetube firetube Fuel natural gas natural gas Product hot water steam Controls O2 trim O2 trim

49 Process Boilers Parallel positioning plus O2 trim 49 Results from university: Firing Rate O2 Enabled Stack Temp ( F) Comb. Efficiency (%) O2 Disabled Stack Temp ( F) Comb. Efficiency (%) Efficiency Improvement (%) O2 (%) O2 (%) (%)

50 Process Boilers Parallel positioning plus O2 trim 50 Results from hospital:

51 51 Process Boilers Parallel positioning plus O2 trim conclusions A base combustion curve is manually programmed into the parallel position control without the O2 trim enabled (controls can operate safely without O2 trim in case O2 sensor fails). The boiler s parallel positioning control was tuned very efficiently with low base excess O2 values. O2 trim compensates for changes in the combustion air temperature. The boilers are located inside a boiler room, therefore the fluctuations in outside air results in only moderate changes in the boiler room and combustion air temperatures. Thus, the benefits of O2 trim are reduced, particularly when a good base combustion curve is programmed during the boiler tuning. Do not recommend boiler O2 trim control for adoption in T24. Energy savings are difficult to quantify and in many cases will not lead to any measurable energy savings.

52 52 QUESTIONS & COMMENTS Matt Tyler

53 53 Water Heater Standby Loss Stakeholder Meeting 2 California Statewide Utility Codes and Standards Program Heschong Mahone Group, Inc.

54 WH2 Standing Loss Outline CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 54 Current code requirements Typical practice Flue damper reduce standing loss High efficiency ready accommodate federal standards Code change proposals

55 WH2 Standing Loss Current Code Requirements CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 55 Federal water heater standards preempt CA to have more stringent CA Title 20 Requirements < 75 kbtu/hr: standby loss included in Energy Factor > 75 kbtu/hr: standby loss measured and reported New federal res WH regulations Storage 55 gallons: EF = ( x Rated Storage Volume in gallons) 40 Gal EF = Storage > 55 gallons: EF = ( x Rated Storage Volume in gallons) 56 Gal EF = 0.76 condensing

56 WH2 Standing Loss Typical Practice CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 56 Water heating represents more than 30% of total residential building energy use Multi-family and hotel/motel buildings use commercial grade water heaters or boilers Gas water heaters with low standby loss Forced draft water heaters Tankless water heaters Condensing water heaters Water heaters with integral flue damper

57 WH2 Standing Loss Code Change Consideration CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 57 Installation of a flue damper as part of the flue exhaust system to reduce standby stack heat loss Availability of third-party flue dampers Feasibility of working with water heater controls Compliance options: high efficiency water heaters Accommodation coming WH efficiency standards Installation of a 110V electric outlet in the water heater closet or near water heater in garage Exhaust system: compatible with high efficiency water heaters Installation of condensate drain Installation of ¾ inch gas pipe line: tankless water heater

58 WH2 Standing Loss Flue Damper Energy Impact CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 58 In a 40-Gal WH, stack heat loss represent ~ 43% of the total heat loss or 17% of total WH energy consumption Stack loss during standby 42.7% Jacket 11.4% Bottom skirt 4.1% Inlet line 1.3% Fitting 1.7% Stack loss while in standby (22.7hr) 17% Jacket (24hr) 4% Fitting & other losses (24hr) 3% Stack loss while firing 38.9% Stack loss while firing 15% (1.5hr) 61% Delivered Hot Water (0.36hr) Percentage Heat Loss from Tank System Energy Flow From a TANK simulation study performed by Peter Biermayer and Jim Lutz of LBNL

59 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 59 Flue Damper Energy Savings Estimate Residential: 24 Therms/yr 40 Gal, EF = 0.60, RE = 0.78 Flue damper effectiveness = 0.65; lower if installed after flue diverter Commercial: 30 Therms/yr 100 Gal 200KBtu WH Standby loss ratings: 1000 Btu/hr Flue damper effectiveness = 0.65

60 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM Flue Damper Cost Effectiveness 60 Natural gas TDV NPV Res: $27.68 (30yr) Nonres.: $14.59 (15yr) and $25.96 (30yr) Lifecycle savings Res WH: $ Commercial WH: $437.7 (15yr) and $778.8 (30yr) Cost: Flue damper cost: $250 Installation cost need to include control modification

61 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 61 Flue Damper Availability & Feasibility Integral flue dampers are used Bradford White res WH models with 0.67 EF Commercial WH with large heat input After market flue dampers Mostly for boilers - control interface exists Non-electrical firing WH control modification Installation feasibility Reliability of buoyancy driven flue dampers Need to be connected to the ignition controls

62 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 62 Flue Damper Alternative WH Blanket Water heater blanket can also reduce standing loss Already required by the 2008 Title 24 Savings are limited cost is low Any feasibility issue?

63 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 63 High Efficiency Ready - Measure Cost Need to compare to future retrofit cost 2015 federal standards / future standards within 30 years Measure Note Add Cost 110V Electric Outlet Exhaust Pipe for HE WH Condensate Drain ¾ Inch gas line Already installed in garage, need to bring close to WH Stainless steel is the only suitable for all WH $0 - $ $ Easily available (what type) $ Material cost difference between ½ and ¾ inch gas line $ DOE rulemaking documents 2. HMG market research Total: $ 194 ~ 378

64 WH2 Standing Loss CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 64 High Efficiency Ready Cost Effectiveness Measure costs vs. retrofit costs Increased market adoption will drive down costs of high efficiency WH DOE standards updates Consumers to enjoy energy savings SF residential buildings WH EF change Therm/yr NPV $ Basic Forced draft Basic Condensing $ $1690 More savings for MF, hotel/motel, food services buildings

65 WH2 Standing Loss Proposed Code Change CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM 65 After-market flue damper not the best solution Enhance water heater blanket requirements Section 113 mandatory requirements for all buildings A 110V electric outlet to be install in the water heater closet or near the water heater in garage Install exhaust pipes compatible with high efficiency water heaters Installation of a condensate drain Installation of ¾ inch gas pipe line

66 66 QUESTIONS & COMMENTS Yanda Zhang