Solar panels and batteries in the Illawarra

Between the escarpment and the sea, conditions change over a few kilometres. Dapto sits back from the ocean but beside Lake Illawarra, which is salt water. Horsley climbs towards the ridge and catches more wind. Shellharbour and Shell Cove are close to open water. A roof at the foot of the escarpment and one by the lake can differ more from each other than either does from Sydney.

That is also why we are careful with output figures. The daily generation number this site models with is a Sydney-region average, not an Illawarra measurement. It is a fair starting point, and your quote is based on your own roof, orientation and shading rather than on a regional figure.

The panels themselves cope with coastal air; they are glass and aluminium built for weather. The mounting is what spends 25 years outdoors in it. Corrosion is cumulative, and it is worst on the small parts: screws, clamps, and anywhere two different metals touch and moisture sits between them.

Exposure falls away with distance from breaking surf, and a sheltered lake or harbour is milder than an open surf beach. The Australian Standard for atmospheric corrosivity, AS 4312, sorts sites into categories on that basis. A beachfront roof at Shellharbour and a house in Dapto may not need the same specification, but both deserve a deliberate one.

An array is a large flat surface fixed to your roof, and the wind load on it rises with exposure and height. The installation standards require the mounting to be designed for the site's wind region and terrain category. On a ridge-line street in Horsley that usually means rails closer together, more roof attachments and shorter overhangs than the same system on a sheltered block. Ask what classification the mounting was designed for; the answer comes straight out of the racking manufacturer's software.

The escarpment sits to the west, so where it matters it takes late-afternoon sun in winter, when the sun is already low. Homes closest to the ridge feel it most. We look at the winter sun path at the assessment, and where afternoons are short we weight the array towards the east and north.

Much of the southern Illawarra is new or changing. At Shell Cove many people are deciding about solar while the house is still being built. Our advice is to install after handover, once there is a meter and an occupation certificate, and to ask the builder for a conduit from the meter box to the roof space and the garage wall while the walls are open. New homes here are often three-phase, which suits a larger system.

In older Shellharbour streets the risk runs the other way: a neighbour's new second storey. There is no general right to sunlight for a rooftop system in NSW. The practical answer is design. Weighting the array away from the boundary most likely to be built up protects it for its whole life.

The same distribution network covers the Illawarra and much of western Sydney, so the export rules are the same. On a flexible export connection, eligible homes can send up to 10kW per phase to the grid most of the time; a fixed limit caps exports at 1.5kW. From November 2026 flexible exports become the default for eligible new and upgraded systems, and they need an internet-connected, CSIP-AUS compliant inverter.

The NSW Emergency Backstop Mechanism is being phased in by postcode for new and upgrading systems up to 200kW, with all of them backstop-enabled by 30 April 2027. Systems already installed are not affected. We lodge the connection application and confirm your limit before install day.