University Facilities Officer s Meeting Universal City October 19, 2009

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1 University Facilities Officer s Meeting Universal City (NEW) 2008 Title 24 Building Energy Efficiency Standards and Revised CSU Compliance Requirements CSU Buildings shall demonstrate compliance with Title 24 Energy Standards utilizing performance based approach (Section 141 Performance Approach: Energy Budgets). One of the energy analysis software programs approved by the California Energy Commission shall be utilized for this compliance. The Prescriptive approach to Title 24 is not acceptable. Title 24 calculations are required at each design phase submittal for overall (all building elements), as well as by each of the three building elements including envelope, indoor lighting, and mechanical & domestic hot water. The results of these calculations shall be included as a summary in a table form as part of the Basis of Design Report submittal. Certificate of Compliance forms shall also be included as part of the final Construction Document package. Several of these forms are required to be placed on the plans. The Performance Certificate of Compliance energy use summary shall indicate that overall and component energy usage meet the CSU goals listed in the table below: % Better than Standard Component Building connected to a central plant with TES tank Building with its own dedicated mechanical system w/o TES New Construction Renovation Projects New Construction Renovation Projects Overall 20% 10.0% 15% 7.5% Envelope Only 0% 0% 0% 0% Indoor Lighting Only Mechanical and Domestic Hot Water Only 0% 0% 0% 0% 0% 0% 0% 0% The percentages above do not include process energy usage as defined by the Energy Standards but do include receptacle loads. A target of 0% means that the component can perform no worse than the prescriptive minimum required by Title 24. If overall or any of the building elements fall short of the percentages indicated in the table above, building components will need to be redesigned until Percent Better than Standard value is greater or equal to percentages indicated above.

2 P a g e 2 The example shown herein is for EnergyPro v , but any other certified program may be used. The percent better than standard column in the table below has been extracted from the Performance Certificate of Compliance energy use summary (PERF-1-C Part 2 of 3). Sample Table Summary Component Percent Better than Standard (excluding process) Comment Overall 15.8% If the building is connected to the central plant with a TES tank, overall building does not comply with CSU target of a minimum compliance margin of equal to or greater than 20 percent. However, if the building is not connected to the central plant and has its own dedicated mechanical system without a TES tank, overall building complies with CSU target of a minimum compliance margin to or equal to or greater than 15 percent. Envelope only -0.5% Building Envelop does not comply with CSU target of a minimum compliance margin of equal to or greater than zero percent. Changes to envelop must be made until Percent Better than Standard value is greater or equal to zero percent Indoor Lighting only 6.5% Indoor lighting systems complies with CSU target of a minimum compliance margin of equal to or greater than zero percent Mechanical & Domestic Hot Water 9.0% Mechanical & Domestic Hot Water systems comply with CSU target of a minimum compliance margin of equal to or greater than zero percent In this example, if the building is not connected to the central plant and has its own dedicated mechanical system the building as a whole meets the 15% overall building energy target and indoor lighting, mechanical & domestic hot water individually meet the 0% target for each discipline. But the envelope design alone does not meet the 0% target. So the building does not comply with CSU goals. The envelope design would have to be improved sufficiently to result in a positive savings.

3 P a g e 3 The Overall analysis includes all building elements. This is accomplished in EnergyPro by marking the check boxes for all disciplines under Options in the Calculations Options window as shown in Figure 1 below. The Calculations Options display can be accessed by clicking on Calculations in the lower lefthand corner, clicking on the applicable simulation type NR T24 Performance, and then selecting the Options tab. Figure 1. EnergyPro Calculation Options Screen All Disciplines Modeled The program is executed and the results can be seen by viewing the Performance Report on the top of the PERF-1-C form, part 2 of 3, as shown in Figure 2. In this example, the building modeled with all disciplines has a margin of compliance of 15.8% excluding process see the Percent Better than Standard line in the Annual TDV Energy Use Summary. If the building is not connected to the central plant supported by a TES tank and has its own dedicated mechanical system without a TES tank then the building complies overall with a target Percent better than Standard of 15%. However if the building is connected to the central plant supported by a TES tank, the building does not comply with a target Percent better than Standard of 20% and will require redesign of the building systems. Figure 2. Performance Certificate of Compliance TDV Summary All Disciplines Modeled

4 P a g e 4 We must also test the performance of each discipline. First, let s check the envelope. To do this, check only the Envelope check-box in the Win/DOE tab of the Calculation Options window as shown in Figure 3. Uncheck the Lighting, Mechanical, and Domestic Hot Water components. Figure 3. EnergyPro Calculation Options Screen Envelope Only Figure 4 shows the PERF-1-C results. The envelope alone complies by -0.5%. Thus the envelope does not meet the minimum Title 24 requirements and thus does not meet the CSU target. Changes to the envelope must be made until the Percent better than Standard value is greater or equal to zero. Figure 4. Performance Certificate of Compliance TDV Summary Envelope Only

5 P a g e 5 Next, let s check the lighting. To do this, check only the Indoor Lighting check-box in the Win/DOE tab of the Calculation Options window as shown in Figure 5. Figure 5. EnergyPro Calculation Options Screen Lighting Only Figure 6 shows the PERF-1-C results. The lighting alone complies by 6.5%, exceeding the 0% target for each discipline. So the lighting design meets the target. Figure 6. Performance Certificate of Compliance TDV Summary Lighting Only

6 P a g e 6 Finally, let s test mechanical & domestic hot water systems. To do this, check only the Mechanical and Domestic Hot Water check-box in the Win/DOE tab of the Calculation Options window as shown in Figure 7. Figure 7. EnergyPro Calculation Options Screen Mechanical Only Figure 8 shows the PERF-1 results. The mechanical & domestic hot water systems alone beat Title 24 by 9% and thus complies with the CSU target. Figure 8. Performance Certificate of Compliance TDV Summary Mechanical Only In this example, if the building has its own dedicated mechanical system without a TES tank the building as a whole meets the 15% overall building energy target, and the lighting and HVAC individually meet the 0% target for each discipline. But the envelope design alone does not meet the 0% target. So the building does not comply with CSU goals. The envelope design would have to be improved sufficiently to result in a positive savings. Also if the building is connected to the central plant supported by a TES tank the overall building performance does not comply with the CSU overall building energy target of 20% and building will be required to be redesigned until the CSU building energy target of minimum 20% is met.

7 P a g e T-24 Summary of Changes: Building Energy Efficiency Standards for Residential and Nonresidential Buildings: