J9D5 of the NCC 2022 introduces new provisions to support the future integration of solar photovoltaic (PV) systems and battery storage in buildings.

J9D5 Solar Photovoltaic (PV) and Battery Systems:

The main electrical switchboard of a building must now have four DIN rail spaces and at least two empty three-phase circuit breaker slots labeled with the use of each space for a solar photovoltaic system and a battery system. It must also be large enough to support the installation of solar photovoltaic panels that generate their maximum electrical output due to future regulations.

Roof Space Allocation

A minimum of 20% of the building’s roof space must now be set aside for the potential installation of solar photovoltaic panels.

Part J9D5 of the NCC 2022

Part J9D5 requires new buildings to add provisions for future on-site solar and batteries. This includes:

• Adding labeled spare compartments in the electrical switchboard for protection and metering (Part J9D5 (1)).
• Allowing for usable rooftop space for future PV installation in accordance with Part J9D5 (2), where possible.

Limitations

1. J9D5 is not applicable to buildings with a battery system installed.
2. a. J9D5 (2) is not applicable where 100% of a building’s roof area is shaded for more than 70% of daylight hours.
3. b. J9D5 (2) is not applicable where an alternative on-site renewable energy generation system is provided, with capacity equivalent to the PV system described in J9D5 (2).

Solar Photovoltaic and Battery Systems

Photovoltaic solar cells convert sunlight directly into electricity by the photovoltaic effect. This energy is delivered to the building first, and excess energy is often exported back into the main grid. Batteries can be connected to the solar system to store energy for later use.

Factors for Choosing the Best Solar PV System

• How much electricity you need
• The time of day you use electricity
• How much roof space is available
• The direction and orientation of panels

Compliance Calculations

To comply with J9D5 (2), a simple calculation is needed. For example, a Class 5 office building in climate zone 6 requires:

• Minimum solar PV installed peak output = 65 W/m².
• For 35,000 m² conditioned space: 65 W/m² x 35,000 m² = 2,275,000 W or 2,275 kW.

Assuming one solar PV panel has a potential of 400 W and a size of 2.1 m²:

• Panels required: 2,275,000 W / 400 W = 5,688 panels.
• Solar panel area required: 5,688 x 2.1 m² = 11,903 m².

With 1,800 m² of available roof space, J9D5 (2)(a) is a more feasible approach, requiring PV installation on all available, unshaded roof space.

Benefits of Renewable Solar Energy

Solar energy is renewable, non-polluting, and accessible everywhere. It is ideal for remote locations and can generate electricity on a large scale. Solar farms are silent and require minimal maintenance. Additionally, the cost of photovoltaic cells has significantly decreased, making solar energy more viable.

Solar PV Industry Growth in Australia

The solar PV industry is booming due to rapid cost reductions and the competitiveness of renewable energy compared to fossil fuels. From 2010 to 2019, the global levelized cost of electricity for large-scale solar decreased by 85%. Renewables now outperform fossil fuels in many scenarios, particularly when new capacity is needed.