ASHRAE-90.1-2022- - Page 222
Extracted Content
Table 12.5.1 Modeling Requirements for Calculating Design Energy Cost and Energy Cost Budget (Continued)
| 14. Modeling Exceptions (continued) | Col2 |
|---|---|
| **Exception:**Components and_systems_ in the_proposed design_ may be excluded from the simulation model provided that 1. component_energy_ use does not affect the_energy_ use of_systems_ and components that are being considered for trade-off and 2. the applicable prescriptive requirements of Sections 5.5, 6.5, 7.5, and 9.5 applying to the excluded components are met. | |
| 15. On-Site Renewable Energy | |
| On-site renewable energy_in the_proposed design shall be determined as follows: a. Where a complete_system_ providing_on-site renewable energy_ exists, the model shall reflect the actual_ system_ type using actual component capaci- ties and efficiencies. b. Where a_system_ providing_on-site renewable energy_has been designed, the_system_ model shall be consistent with design documents. c. Where no_system_ exists or is specified to provide_on-site renewable_ energy, no_system_ shall be modeled. | On-site renewable energy_shall be included in the_budget building design when required by Section 10.5.1, and shall be determined as follows: a. Where a_system_ providing_on-site renewable energy_ has been modeled in the_proposed design_, the same_system_ shall be modeled identically in the_budget building design_, except the rated capacity shall meet the requirements of Section 10.5.1.1. Where more than one type of_on-site renewable_ energy system is modeled, the total capacities shall be allocated in the same proportion as in the_proposed design_. b. Where no_system_ exists or is specified to provide_on-site_ renewable energy in the_proposed design_, on-site renewable energy shall be modeled as an unshaded photovoltaic system with the following physical characteristics: • Size: Rated capacity per Section 10.5.1.1 • Module Type: Crystalline silicon panel with a glass cover, 19.1% nominal efficiency and temperature coefficient of –0.19%/°F; performance shall be based on a reference tem- perature of 77°F and irradiance of 317 Btu/ft2·h. • Array Type: Rack-mounted array with installed nominal operating cell temperature (INOCT) of 103°F • Total system losses (DC output to AC output): 11.3% • Tilt: 0-degrees (mounted horizontally) • Azimuth:180 degrees If the_on-site renewable energy system_ cannot be modeled in the simulation program, Section 12.4.5 shall be used. |
220 ANSI/ASHRAE/IES Standard 90.1-2022 (I-P)