The duplication of the Augusta Highway between Port Wakefield and Lochiel is a major regional transport upgrade for South Australia. As part of this work, the Department for Infrastructure and Transport (DIT) required improved lighting at the Nantawarra Road intersection, a key point on a nationally significant freight and passenger route. While intersection lighting is standard on high-speed corridors, this site posed a challenge: the cost and complexity of bringing grid power to a remote section of highway made a conventional installation difficult to justify.
DIT and the project team needed a solution that could achieve AS1158.1.1 Category V5 lighting without relying on the grid. Green Frog Systems was engaged to design and supply a solar-powered system that could meet these standards and operate reliably across a range of regional weather conditions. The result is a fully off-grid installation using ASPIRE 75W solar lighting systems, installed on 10.5 metre slip-base poles and fitted with precision optics and a 4.5 metre outreach to ensure full coverage of the intersection.
Meeting Category V5 Standards Without Grid Power
Category V5 lighting is usually delivered with mains-powered luminaires in the 100-150W range. These fittings are widely used by road authorities and have long been the default choice for major highways. At Nantawarra, the challenge was not the lighting design itself but the lack of economical grid access. Extending electrical infrastructure would have required substantial trenching and civil works, adding significantly to project cost and time. This prompted the team to assess whether a purpose-built solar system could provide the same lighting performance expected from a grid-connected installation.
There was also the question of confidence. Solar lighting is often viewed cautiously on high-speed roads, especially when it must perform all night and through extended periods of low solar input. For a V5 intersection on a major corridor, the system needed to demonstrate consistent and predictable performance. Green Frog Systems designed each ASPIRE unit with five high-capacity batteries housed inside the pole, providing a minimum of four days of autonomy. Combined with the 4.5 metre outreach arms, the luminaires deliver the required luminance and uniformity levels without relying on any external power source.
Building on Earlier Pilots
The Augusta Highway project follows earlier deployments in Victor Harbor where Green Frog Systems trialled solar lighting on a road with similar V class lighting requirements. That installation confirmed that Australian designed solar systems provided more than adequate lighting for major roads, not just for lower speed or pathway applications.
The data from that project contributed to a larger rollout along the Stuart Highway, where more than 100 Aspire solar lighting systems were installed across five key roadhouses. These sites operate largely on diesel generation, so reducing electrical demand was a major benefit. The rollout delivered highway grade lighting to locations where power constraints would normally limit what could be achieved.
Design Considerations and Project Delivery
Lighting design for the intersection focused on even coverage across all conflict points. Pole locations, mounting height and optics were selected to achieve uniformity appropriate for a high-speed rural environment. The use of 10.5 metre slip-base poles aligns with established safety requirements while providing the structural capacity needed for solar equipment.
Removing the need for grid power simplified delivery. Without trenching or cabling, installation was limited to pole placement and commissioning, reducing site works and shortening the construction timeline. Avoiding electrical upgrades also reduced overall project cost, which is particularly important where assets are spread over large distances.
The ASPIRE systems were supplied as integrated assemblies containing panels, batteries and luminaires. This reduced staging requirements and installation time for the install team, allowing the lighting to be brought online as the wider duplication works progressed.
Outcome
The completed installation now delivers Category V5 lighting at the Nantawarra Road intersection, improving visibility and safety at an important point on the Augusta Highway. It also highlights the growing role of solar lighting in major infrastructure projects, particularly where grid access is limited or uneconomical.
Read the full project case study via the Green Frog Systems website.
