Commercial EV Charging on the Gold Coast: Charging Off Your Own Roof

Every electric vehicle stores DC power in its battery, and the grid delivers AC. Something has to convert one into the other. The only real question is whether that happens inside the car or inside the charger.

An AC charger passes AC to the vehicle and lets the car's onboard charger do the conversion. That means the car sets the ceiling, not the wall unit. A larger AC charger will not make a vehicle with a modest onboard charger any faster.

A DC charger does the conversion itself and feeds the battery directly, which is why it is quicker. It is also physically bigger, considerably more expensive, and much hungrier for supply.

Neither one is better. They answer different questions, and the question is always how long the vehicle is standing still.

Workplace charging, fleet charging and customer charging get sold as one product. They are not one product. They have different users, different dwell times and different ways of failing.

Staff parking is the gentlest case. Cars arrive in the morning and leave in the afternoon, so the window is long and AC covers it comfortably. The interesting design problem is sharing supply across many bays, not speed.

Fleet charging is an operations problem before it is an electrical one. What matters is whether a vehicle has to be ready between shifts or only by the next morning. That one fact decides AC or DC on its own.

Customer and visitor charging is different again. Someone topping up while they shop or eat wants visible progress in a short stay, which pushes towards faster hardware in a small number of bays, plus a way of handling who pays.

This is the part that catches people out. Choosing a charger takes an afternoon. Working out whether your site can feed it is the actual project.

Chargers draw hard, and unlike lighting they can draw hard for hours at a time. What matters is your incoming supply, your main switch rating, and how much of that is already spoken for by everything else running on site.

Whether you are on single-phase or three-phase, how far the cable has to run from the board to the car park, and how much headroom you have at your busiest hour will all move the price more than the unit on the wall does.

There is often a way around an upgrade. Load management shares a fixed amount of supply across several chargers, throttling them when the site is busy rather than tripping anything over.

It is also why nobody can price this over the phone. A quote for a commercial EV charger given without seeing your board is a guess, and guesses are always cheap until the electrician arrives.

Here is why this belongs next to a solar conversation. A solar system generates through the middle of the day, and most workplace charging happens through the middle of the day. That overlap is the whole opportunity.

The economics fit in one sentence. Power you generate and use on site avoids what you would have paid to buy it, while power you export earns a feed-in credit that is usually lower than the rate you buy at.

So a car park full of vehicles charging at midday quietly converts exported energy into avoided energy. For most businesses that is the best use they will find for a sunny afternoon.

It also changes how the system should be sized. If chargers are coming, they belong in the load profile from the beginning rather than being bolted on later. Our guide to how many panels your business needs walks through how that calculation is done.

That neat overlap disappears the moment your vehicles are out all day and back at night. A fleet that charges after dark is charging on grid power, however many panels are on the roof.

This is where a battery can earn its place. It holds what the roof made during the day so it can be used in the evening, which is the same argument we set out on our commercial solar batteries page.

Whether it stacks up depends on your tariff and how much of your charging is genuinely after hours. That is worth measuring rather than assuming, in either direction.

Scheduling is the cheaper lever and it gets skipped constantly. Most commercial chargers can be told when to run, so any vehicle that only needs to be full by morning can be pushed into the solar window or away from your peak period.

Demand charges are worth understanding before you add chargers. On many commercial tariffs part of the bill is set by your highest demand, so several chargers all starting at once can cost you in a way the energy alone does not explain.

We will not tell you what your install will cost, or how fast your vehicles will charge, from an article. Both depend on your supply, your cable run and the cars themselves. Any figure written here would be a guess wearing the costume of a fact.

We also will not tell you that chargers pay for themselves. Sometimes the case is clean, and sometimes the honest answer is that it is a staff benefit or a reason for customers to stop. That is a perfectly good reason to do it, as long as you decide it with your eyes open.

What you should expect from anyone quoting the work is that they physically looked at your board, and that they can separate the price of the charger from the price of the electrical work needed to feed it.

How we scope and install this is set out on our commercial EV charging page. The questions below matter more than the brand on the unit, and they work just as well on somebody else's quote.