Appendix NI (RI) On-Site Renewable Energy
Section NI101 (RI101) General
NI101.1 (RI101.1) Scope.
These provisions shall apply where on-site renewable energy is required.
Section NI102 (RI102) General Definitions
ANNUAL SOLAR ACCESS.
The ratio of annual solar insolation with shade to the annual solar insolation without shade. Shading from obstructions located on the roof or any other part of the building are not included in the determination of annual solar access. Shading from existing permanent natural or person-made obstructions that are external to the building, including but not limited to trees, hills and adjacent structures, are included in annual solar access calculations.
PHYSICAL RENEWABLE ENERGY POWER PURCHASE AGREEMENT.
A contract for the purchase of renewable electricity from a specific renewable electricity generator to a purchaser of renewable electricity.
POTENTIAL SOLAR AREA ZONE.
The combined area of any steep slope roofs oriented between 90 degrees and 300 degrees of true north and any low slope roofs where the annual solar access is 70 percent or greater.
Section NI103 (RI103) On-Site Renewable Energy
NI103.1 (RI103.1) General.
Buildings shall comply with Section N1101.13 and the requirements of this section.
NI103.1.1 (RI103.1.1) Installed capacity.
An on-site renewable energy system shall be installed on, or at the site of, the building with a peak rated capacity, measured under standard test conditions, in accordance with one of the following:
- 1.
For one- and two- family dwellings, townhouses and other Group R-3 occupancies, the peak rated capacity shall be not less than 2 kW.
- 2.
For Group R-2 or R-4 residential buildings, the peak rated capacity shall be not less than 0.75 watts per square foot (8.07 W/m2) multiplied by the gross conditioned floor area.
- 3.
Where a building includes both commercial occupancies and R-2 or R-4 occupancies required to comply with this code, the peak capacity shall be not less than 0.75 watts per square foot (8.07 W/m2) multiplied by the gross conditioned floor area of the Group R-2 and R-4 occupancies.
The capacity of installed on-site renewable energy systems used to comply with this appendix shall be in addition to the total capacity of installed on-site renewable energy systems used to comply with all other requirements of this code.
Exceptions:
- 1.
A building with a permanently installed domestic solar water heating system sized with a solar savings fraction of not less than 0.5 based on the total service water heating load of all residential occupancies.
- 2.
One- and two-family dwellings, townhouses and other Group R-3 Occupancies in Climate Zone 4C, 5C or 8.
- 3.
Group R-2 or R-4 occupancies in Climate Zone 8.
- 4.
Buildings where the potential solar zone area is less than 300 square feet (28 m2).
- 5.
Buildings with a physical renewable energy power purchase agreement with a duration of not less than 15 years from a utility or a community renewable energy facility and for not less than 80 percent of the estimated whole-building electric use on an annual basis. This exception shall not apply where off-site renewable energy credits are used to comply with the requirements of Section N1108.
- 6.
NI103.1.1.1 (RI103.1.1.1) Alternate capacity determination.
Where compliance is demonstrated in accordance with Section N1105 and the proposed design and standard reference design are adjusted in accordance with Items 1 and 2, the required capacity of the installed renewable energy systems shall be permitted to differ.
- 1.
Proposed Design. Where applicable, the proposed design shall comply with one of the following:
- 1.1.
Where one or more systems providing on-site renewable energy are included in the construction documents, the systems shall be modeled in the proposed design with a design capacity not greater than the required capacity in accordance with Section NI103.1.1. A combination of on-site renewable energy systems shall be permitted to be included in the proposed design.
- 1.2.
Where no on-site renewable energy systems are specified in the construction documents, no on-site renewable energy systems shall be modeled in the proposed design.
- 1.1.
- 2.
Standard Reference Design. Where applicable, the standard reference design shall comply with one of the following:
- 2.1.
Where a proposed design includes one or more on-site renewable energy systems, the same systems shall be modeled identically in the standard reference design except the total rated capacity of all systems shall be equal to the required capacity in accordance with Section NI103.1.1. Where more than one type of on-site renewable energy system is modeled, the total capacity of each system shall be allocated in the same proportion as in the proposed design.
- 2.2.
- 2.1.
CRITERIA | DESIGN MODEL |
Size | Rated capacity not less than required in accordance with Section NI103.1.1. |
Module type | Crystalline silicon panel with a glass cover, 19.1% nominal efficiency and temperature coefficient (Tc Power) of -0.37%/°C. |
Array type | Rack-mounted array with installed nominal operating cell temperature (INOCT) of 103°F (45°C). |
Total system losses (DC output) | 11.3% |
Tilt | 0 degrees (mounted horizontally) |
Azimuth | 180 degrees |
For SI: °C = [(°F) – 32]/1.8.
NI103.1.2 (RI103.1.2) ERI with OPP requirements.
Where compliance is demonstrated in accordance with Section N1106.5 using the Energy Rating Index with OPP, a project shall comply with the requirements of this appendix if the rated proposed design and confirmed built dwelling are shown to have an ERI less than or equal to the values in Table NI103.1.2.
CLIMATE ZONE | ENERGY RATING INDEX WITH OPP |
0 and 1 | 35 |
2 | 34 |
3 | 33 |
4 | 40 |
5 | 43 |
6 | 43 |
7 and 8 | 46 |