## 9.5 Exceptions

There are five exceptions to the solar zone area requirement described in §110.10(b)1B of the Energy Standards. Four of these five exceptions are described below. Although the language in the Standards implies that these four exceptions only apply to the solar zone requirements, the intent of the Energy Standards is for the exceptions to apply to the solar zone requirement as well as the interconnection pathway requirements described in §110.10(c) and the documentation requirements described in §110.10(d)

1. PV System Is Permanently Installed (Exception 1 to §110.10(b)1B): Buildings are exempt from solar zone, interconnection pathway and documentation requirements if a solar PV system with a nameplate direct current (DC) power rating of no less than 1 watt per square foot of roof area is permanently installed at the time of construction. The nameplate rating must be measured under standard test conditions. The permanently installed solar PV system can be installed anywhere on the building site. To verify compliance with this exception document NRCI-SPV-01-E Certificate of Installation: Solar Photovoltaic System must be submitted.

2. SWH System Is Permanently Installed (Exception 2 to §110.10(b)1B): Buildings are exempt from solar zone, interconnection pathway and documentation requirements if a domestic SWH system is permanently installed at the time of construction. The SWH system must comply with §150.1(c)8Ciii, the prescriptive solar water heating system requirements when installing a water-heating system serving multiple dwelling units. The permanently installed domestic SWH collectors can be installed anywhere on the building site. To verify compliance with this exception document NRCI-STH-01-E Certificate of Installation: Solar Water Heating System must be submitted.

3. High-Rise Multifamily Building With Occupant Controlled Smart Thermostats (OCST) and Efficient Equipment Installations: High-rise multifamily buildings that comply with Items 1 and 2 below are exempt from solar zone, interconnection pathway, and documentation requirements.

1. All thermostats in each dwelling unit are occupant controlled smart thermostats (OCST) with communications capabilities enabled to receive and respond to demand response signals. An OCST is a setback thermostat with communication capabilities that enable the occupant to receive demand response related messages and respond to those signals by automatic adjustment of the thermostat setpoint as described in Joint Appendix JA5 (subject to occupant participation). Enabling communications capabilities requires that the OCST has one of the following: onboard communications capabilities, an installed communications module for OCSTs with removable communications module(s), or an installed communications gateway for an OCST where an external gateway is required for communications.

OCST must be certified by the Energy Commission to meet the requirements described in Joint Appendix JA5.

2. One of the following additional measures is followed:

a. Efficient Appliances: Install, in each dwelling unit, a dishwasher that meets or exceeds ENERGY STAR® requirements, along with either a refrigerator that also meets or exceeds ENERGY STAR requirements or a whole-house fan that is driven by an electronically commutated motor.

b. Home Automation: Install, in each dwelling unit, a home automation system that can (at a minimum) control either the appliances or the lighting and can respond to demand response signals. This measure can be met by the same device that performs the OCST functions if that device is also capable of controlling lighting or appliances.

c. Graywater Irrigation: Install alternative plumbing (piping) to permit the discharge from any clothes washers (whether in individual dwelling units or communal laundry rooms) and all showers and bathtubs to be used for an irrigation system. This graywater system must comply with the California Plumbing Code and any applicable local ordinances.

d. Rainwater Catchment: Install a rainwater catchment system that is able to capture water flowing from at least 65 percent of the roof area of the building. This catchment system must comply with the California Plumbing Code and any applicable local ordinances.

4. Roof Designed for Vehicle Traffic or Heliport (Exception 5 to §110.10(b)1B): Buildings are exempt from solar zone interconnection pathway and documentation requirements if the roof is designed for vehicle traffic (parking lot) or if the roof is designed as a helicopter landing zone.

5. Exception (Exception 3 to §110.10(b)1B allows the minimum solar zone area to be reduced if the solar access at the building site is limited. Exception 3 to §110.10(b)1B is detailed above in the minimum solar zone area section of this chapter (Section 9.3.1).

Example 9-6

Question:

An office building has a total roof area of 5,000 SF. The total roof area covered by skylights is 200 SF. A solar PV system with a DC power rating (measured under standard test conditions) of 4 kilowatts (kW) will be installed. The collection panels for the 4 kW system will cover 400 SF. Does the building have to have to include a solar zone in addition to the installed solar PV system?

Answer:

Yes. To be exempt from the solar zone requirement, the solar PV system must have a power rating equal to 1 watt for every square foot of roof area, or in this case 5 kW (see equation below).

The minimum solar zone for this building is 720 SF. (See calculation below.) The 400 SF on which the solar PV system is installed does count toward the minimum solar zone area, so an additional 320 SF would need to be allocated to complete the minimum solar zone requirement.