Solar panels in Avoca Beach

As an estimate, a 6.6kW system starts from $7,410, a 10kW system starts from $10,300 and a 13.2kW system starts from $11,250 (with battery prices starting from $4,290), with the STC discount for postcode 2251 already taken off (incl. GST for metro areas; regional areas subject to freight and travel costs). Those are starting estimates for a straightforward install, not a fixed price. Close to the water, the mounting hardware is the line most likely to move the number — upgraded rails and fasteners cost more than the standard product, and they should be itemised rather than absorbed quietly.

Avoca Beach is in STC Zone 3, rating 1.382. In 2026 a 6.6kW system creates 45 certificates, worth roughly $1,710 off the price, and a 10kW system 69 certificates, roughly $2,622. It is a discount applied at the point of sale, not a grant you apply for afterwards. The certificates depend on capacity and postcode only — being on the coast changes the hardware, not the rebate.

It shortens the life of the wrong hardware, which is a different problem and a solvable one. Panels are glass in an anodised aluminium frame and they cope with salt air; so do inverters mounted sensibly out of the weather. What accumulates damage over twenty-five years is the metalwork holding everything down — brackets, rails, roof fixings and fasteners. Specified for the conditions they are fine. Specified for a house ten kilometres inland and put on a roof two streets from the beach, they are a slow and expensive problem that nobody notices until something moves.

Two things, in writing. First, the corrosivity category the quote assumes: the Australian standard for atmospheric corrosivity grades sites by how much salt they get, with the most severe category covering roughly the first couple of hundred metres from breaking surf and the grades stepping down as you move inland. Second, the actual materials — marine-grade 316 stainless for fasteners rather than 304 or zinc-plated, and a mounting system rated for that category rather than the manufacturer's standard product. If a quote names neither, you are not comparing like with like on price.

It is worth checking, because this is the part that is quietly conditional. Mounting manufacturers commonly publish a distance-from-coast limit for their standard product and sell a coastal or marine variant for everything inside it. If your house is inside that limit and the standard rails go on anyway, the system still works perfectly on day one — what you have lost is the warranty, and you find out in year twelve. Ask which mounting system is on the quote and what its documentation says about distance from the surf. Ask us that too.

Rarely, and be sceptical of anyone selling you an annual clean. Rain does most of the work on a tilted array, and the gain from cleaning glass that is already mostly clean is small. The inspection that is actually worth paying for here is the one nobody sells: someone going up every few years to look at the fixings, the rail joints and the cable clips, which is where coastal wear shows up first. Monitoring tells you about the electrical side for free — a system quietly producing less than it did is the signal to act on.

The distribution network that owns the poles and wires in your street approves it — not your retailer — and we lodge the application for you. On a flexible export connection, a complying system up to 30kW is automatically approved to export up to 10kW per phase. On a fixed export connection, the approval is 3kW per system. If your home has no reliable internet, exports are limited to a static 1.5kW per system until a connection is available. Anything above 10kW per phase is assessed site by site.

If you are installing new solar or upgrading an existing system, yes. Your distribution network is phasing the NSW Emergency Backstop Mechanism in by postcode from 30 November 2026, with full implementation by 22 February 2027. It applies to new and upgrading systems up to 200kW, which must use equipment compliant with the CSIP-AUS standard, and the installer runs a short capability test at installation. Systems already on the roof are not affected.