1、4783 2001 Seattle Energy Code: Striving for 20% Total Building Energy Savings Compared to Standard 90.1m1999 John Hogan, PE, AIA Member ASHRAE ABSTRACT Thispaperprovides an example ofa local energy code that achieves a significant energy esciency improvement in build- ings compared to ANSI/ASHRAE/IE
2、SNA Standard 90.1-1999 und describes the methodology for estimating the relative energy savings. First, the paperprovides a list of key measures in the 2001 Seattle Energy Code that achieve greater energy savings than Standard 90.1-1999 (unamended). Then, using the exact same methodology employed by
3、 the US Department of Energy to evaluate Standard 90.1 -I 999 under EPAct, the inputfiles have been modified and additional parametric runs done to model the requirements in the Seattle Energy Code. The paper presents energy savings by building ype for the 2001 Seattle Energy Code. The paper expands
4、 beyond the federal government analysis to include all of the energy consumption associated with the buildingproject, both interior and exterior. In particular, estimates are presented of associated energy consumption for elevators, parking garage ventilation, park- ing garage lighting, surface park
5、ing lighting, and perimeter/ faade lighting to facilitate their inclusion in analyses by others. (Note thatdddendurn e to ANSUASHRAELESNA Stan- dard 90.1-2001 adds a new Appendix G that speci9es that the entire energy consumption of the project is to be includedwhen making such comparisons.) INTRODU
6、CTION The City of Seattle has been recognized for its leadership in the adoption and enforcement of energy codes. While the first comprehensive Seattle Energy Code took effect in Febru- ary 1980 (Seattle 1980), Seattle has had residential insulation requirements since 1974 (Seattle 1974) and the fir
7、st furnace sizing and duct insulation requirements took effect in 1927 (Seattle 1927). Soon after ASHRAE Standard 90-75 (ASHRAE 1975) was published, the City of Seattle passed Resolution 25257 (Seattle 1976) indicating the citys intent to adopt that standard, subject to revisions. During review of S
8、tandard 90-75 by a task force of citizens from the building- related professions, additional energy savings improvements were identified for new construction and there was a recogni- tion that it was essential to have energy efficiency require- ments for alterations to existing buildings. As a resul
9、t, the 1980 Seattle Energy Code (Seattle 1980) contained building envelope requirements, mechanical system criteria, and light- ing power allowances and control requirements that achieved significant energy savings to relative to Standard 90-75. Thus, the city and its design professionals learned th
10、at ASHRAE Standard 90, while an important baseline, was really only a starting point and that energy codes for building construction could achieve greater energy savings across all construction sectors, including both new construction and alterations to existing buildings. During the process of maki
11、ng subsequent updates to the Seattle Energy Code in 1984, 1986, 1991, 1994, and 1997, Seattle reviewed the latest versions of Standard 90 (ASHRAE 1980, 1989) and consistently found opportunities to achieve greater energy savings. As a result, in 2001, the city adopted a policy that set goals for fut
12、ure versions of the Seattle Energy Code that, while using Standard 90 as a baseline, recognized the opportunities for greater energy savings. Resolution 30280 (Seattle 200 la) directs the Seattle Department of Planning and Development, DPD (formerly the Department of Design, Construction and Land Us
13、e, DCLU) to include in its review of Energy Code amendments: John Hogan is senior energy analyst for the Seattle Department of Planning and Development, Seattle, Washington. 444 02005 ASHRAE. options for amending the Seattle Energy Code to achieve energy savings up to 20% beyond the current . ASBRAE
14、IESNA Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings. DPD DCLU shall report to City Council on proposed Energy Code amendments by July 1,2001, including an analysis of the potential for reduction in total nonresidential building energy consumption if such code ame
15、ndments are adopted. DPD DCLU and SCL will propose to the City Council similar options for amendments to the Seat- tle Energy Code every three years, based on the schedule for amendments to the Washington State Energy Code. These proposed amendments should seek to achieve up to 20% enhanced energy e
16、fficiency beyond the current version of ASHRAEfiESNA Standard 90.1. Note that this language specifically states that calculations are to be done on the basis of “total nonresidential building energy consumption.“ In addition, the resolution directs DPD to provide amendments for 20% energy savings re
17、lative to Stan- dard 90.1 for all future Seattle Energy Code updates. Just prior to this, Standard 90.1-1999 (ASHRAE 1999) was published. Pursuant to the 1992 Energy Policy Act (EPAct 1992), the US Department of Energy (federal government) began their evaluation of this update to Standard 90.1 to de
18、ter- mine if it saved energy relative to the previous version, Stan- dard 90.1-1989 (ASHRAE 1989). Note that the federal government comparison is done for the unamended versions of Standard 90.1, e.g., Standard 90.1-1989 (ASHRAE 1989) without addenda is compared with Standard 90.1-1 999 (ASHRAE 1999
19、) without addenda. Addenda are not consid- ered until they are included in the next published version. Detailed information on the federal government analysis was published in the Federal Register on 15 July 2001 (Department of Energy, Office of Energy Efficiency and Renewable Energy, Docket No. EE-
20、DET-02-00 1). It is also available on the federal government Web site at http:/ www.energycodes.gov/implement/determinations_com.stm. This paper lists key measures in the 2001 Seattle Energy Code that achieve greater energy savings than Standard 90.1- 1999 unamended (ASHRAE 1999). Then, using the ex
21、act same methodology employed by the federal government to evaluate Standard 90.1 unamended (ASHRAE 1999) under EPAct, the paper presents energy savings by building types. This analysis of energy savings was done by the same federal government staff that performed the national energy analysis using
22、the same computer modeling tools. The City of Seattle staff provided the inputs for the Seattle Energy Code varia- tions but did not actually perform the analysis. The paper then expands beyond the federal government analysis to include all of the energy consumption in the build- ing project, both i
23、nterior and exterior. In particular, estimates are presented of associated energy consumption for elevators, parking garage ventilation, parking garage lighting, surface parking lighting, and perimetedfaade lighting to facilitate their inclusion in analyses by others. (ASHRAE has adopted this total
24、building energy consumption approach when making comparisons. Addendum e to ANSUASHRAEAESNA Stan- dard 90.1-2001 ASHRAE 20011 adds a new Appendix G. Standard 90.1-2004 will contain this appendix.) KEY MEASURES IN THE 2001 SEATTLE ENERGY CODE The Seattle Energy Code requirements are generally more st
25、ringent across the board when compared to the 1999 version of Standard 90.1 (ASHRAE 1999). However, not all of the measures are modeled in the federal government proce- dure. Building Envelope The Seattle Energy Code requirements are generally more stringent across the board than Standard 90.1-1999
26、(ASHRAE 1999). As it is based on the Washington State Energy Code, the Seattle Energy Code has more stringent requirements for nonresidential spaces with electric resistance space heat. The requirements for spaces with gas space heat are used here for the purposes of comparison, and the values liste
27、d are for those components modeled in the federal govem- ment analysis: 1. 2. 3. 4. 5. Roof U-factor (nonresidential use, roof with insulation above the roof): U-0.063 Btu/h U-0.050 BtUni.“F (U-0.28 W/m2.K) for the 2001 Seattle Energy Code. Wall U-factor (nonresidential use, metal frame walls): U- 0
28、.124 BtUnift?“F (U-0.70 W/m2.K) for Standard 90.1 (ASHRAE 1999); U-0.084 StUni.fi2.“F (U-0.48 W/m2.K) for the 2001 Seattle Energy Code. Slab-on-grade U-factor, effective: UefleCtive 0.770 Btu/ h+ U-0.490 Btu/ h.ft2.“F for the 2001 Seattle Energy Code. Fenestration U-factor (O-40%/40-50% of the wall
29、area): U-0.5710.46 BtUni4?.“F (U-3.2412.61 W/m2K) for Stan- dard 90.1 (ASHRAE 1999); U-0.4YO.40 Btuni4P.“F (U-2.56/2.27 W/m2.K for the 2001 Seattle Energy Code. Fenestration SHGC (O-40%/40-50% of the wall area): SHGC-0.390.26 for Standard 90.1 (ASHRAE 1999); SHGC-0.40/0.35 for the 2001 Seattle Energ
30、y Code. For a complete listing of the building envelope require- ments used in the comparison for both Standard90.1-1999 (ASHRAE 1999) and the Seattle Energy Code, see Appen- dix A. Mechanical Systems systems with series-type fan-powered terminal units. Electrically commutated motors in variable air
31、 volume ASHRAE Transactions: Research 445 Table I. Comparison of Site Energy Consumption for ASHRAE/IESNA Standard 90.1-1999 and Second Draft of the 2001 Seattle Energy Code (SEC) Before Adjustments for Other Energy End-Uses Education 21.8% 25.82 20.84 46.67 0.0% 21.01 21.30 42.31 Food service 2.7%
32、78.68 44.80 123.48 0.0% 67.81 46.25 114.06 9.3% 20.27 21.27 41.54 11.0% 7.6% 64.62 46.18 110.79 10.3% Lodging Office Retail 7.9% 30.74 19.39 50.13 0.0% 27.03 19.47 46.50 7.2% 25.39 19.41 44.79 10.6% 19.0% 37.45 5.55 43.00 0.0% 32.38 5.27 37.65 12.4% 30.33 5.25 35.58 17.3% 24.6% 40.71 3.58 44.28 0.0%
33、 32.40 3.81 36.21 18.2% 30.41 3.79 34.20 22.8% Lighting 1. Occupancy sensors: none for Standard 90.1 (ASHRAE 1999); small offices and classrooms for the 2001 Seattle Energy Code. Automatic control of electric lighting in daylight zones: none for Standard 90.1 (ASHRAE 1999); required for the 2001 Sea
34、ttle Energy Code. 3. Office lighting W/SF (includes effects of automatic controls): 1.30 for Standard 90.1 (ASHRAE 1999); 0.96 for the 2001 Seattle Energy Code. 2. Warehouse Weighted average FEDERAL GOVERNMENT ANALYSIS OF ASHRAEAESNA STANDARD 90.1-1999 The US Energy Conservation and Production Act p
35、rovides that whenever ASHRAEIIESNA Standard 90.1 is revised, the US Department of Energy (federal government) must determine whether the new version saves energy compared to the previous version. The federal government analysis was based on seven building types (office, mercantile and service, educa
36、tion, lodging, public assembly, food service, and warehouse and storage) in 1 1 climates (including Seattle) and was done using the BLAST hourly annual energy analysis program. In general, all measures were analyzed as a package for each of the above seven building types; however, separate analyses
37、were done for electric and gas fuels for the space heating system, and separate analyses were done with and without enthalpy economizer for the space cooling system. On July 15,2002, DOE published its determination in the Federal Register (Department of Energy, Office of Energy Efficiency and Renewa
38、ble Energy, Docket No. EE-DET-02- 001) that Standard 90.1- 1999 would improve building energy efficiency by comparing it to Standard 90.1-1989. Key 17.3% 19.14 4.94 24.09 0.0% 10.35 4.06 14.41 40.2% 10.35 4.06 14.41 40.2% 33.61 12.47 46.08 0.0% 26.72 12.70 39.42 14.4% 25.41 12.68 38.09 17.3% assumpt
39、ions are listed in Appendix A. In addition to the Federal Register, for a summary and more details of that national analysis, see http:/www.energycodes.gov/imple- ment/determinations-com.stm and a detailed explanation of the analysis is available at: http:/www.energycodes.gov/ implement/determinatio
40、nscom_exp.stm. Table 7, on that Web site, estimates overall site energy savings from Standard 90.1-1999at 3.9%comparedto Standard90.1-1989. Theeval- uation did not include energy use by elevators, parking garage lighting and ventilation, and exterior faade lighting. BASE ENERGY ANALYSIS USING USDOE
41、MODEL In June 2000, the Standard 90.1 Committee voted to set a target of a 20% improvement in energy for the 2004 version of Standard 90.1 as compared to the 1999 version. The Standard 90.1 Committee turned to the federal government for ideas for achieving that goal. For consistency, Seattle has als
42、o used the federal government methodology. For a summary of the input parameters for Seattle, see Appendix A, which contains an overview of the federal government model and summary of inputs for energy analysis. The second draft of the 2001 Seattle Energy Code contains improvements over ASHRAEIIESNA
43、 Standard 90.1 - 1999 in building envelope, mechanical, and lighting. Table 1 provides the energy consumption estimates for each of the seven building types and also for a weighted aver- age of all seven. The weighted average of the results of the separate anal- yses with and without enthalpy econom
44、izer in Table 1 indicate that the expanded economizer measure alone (if full econo- mizer were required on cooling units of all sizes rather than only those larger than 65,000 Btu/h) increased the energy savings by roughly 3% overall (5% for the office building, less 446 ASHRAE Transactions: Researc
45、h for other building types). The input parameters used in the analysis are summarized in Appendix A, 2001 Seattle Energy Code. A few caveats: Weightings are based on national averages. These cases do not yet include energy consumption for elevators, parking garage ventilation, parking garage lightin
46、g, surface parking lighting, and exterior faade lighting. For notes on the methodology to be used to add that energy consumption to the total, see Table 7. While the federal government analysis attempted to provide an overall estimate of the energy consumption impacts, the analysis did not include t
47、he following: 1. Elevator energy consumption estimates, even though Section 10.2 of Standard 90.1-1999 (ASHRAE 1999) does contain minimum motor efficiency requirements. Parking garage ventilation, even though Section 6.2.3.5 of Standard 90.1-1999 (ASHRAE 1999) does require auto- matic garage ventila
48、tion fan system control for fans over 30,000 ch. Parking garage lighting, even though Table 9.3.1.1 of Stan- dard 90.1-1999 (ASHRAE 1999) does have a maximum lighting power allowance of 0.3 WISF. Surface parking lighting, even though Table 9.2.6 of Stan- dard 90.1-1999 (ASHRAE 1999) does require a m
49、inimum lamp efficacy of 60 IrnfW. Perimeterfaade lighting, even though Table 9.3.2 of San- 2. 3. 4. 5. Parking Garage Ventilation Energy Estimates (Table 3) 1. Parking space requirements from Seattle Zoning Code, Section 23.54.015, Chart A Assembly: 1 parking space per 100 ft2 of building area Education: 50% K-12 at 1 space per 450 ft2 (100 spaces per gymnasium), 50% university at 1 space per 500 ft2 Food service: 75% restaurant at 1 per 200 fi2, 25% res- taurant fast food at 1 per 100 fi2 Lodging: 1 space per 4 hotel rooms, 350 ft21room + 50 ft2 circulatiodroom =
