12V Low Voltage vs Solar Garden Lights: Brightness, Cost and What Needs an Electrician
How 12V plug-in transformer lighting and solar lighting compare in a real garden, which needs an electrician, and when to use both.
12V Low Voltage vs Solar Garden Lights: Brightness, Cost and What Needs an Electrician
People searching for garden lighting in Australia tend to end up at one of two options: 12 volt low-voltage lights that run from a plug-in transformer, or solar lights that need nothing but sun. Both are popular, both are DIY-friendly in different ways, and both have a place. This is a plain comparison of how they behave in a real garden, so you can choose by job instead of by habit. (If you want the broader mains versus solar picture, our earlier post on solar vs wired outdoor lighting covers that. This one is specifically about the 12V option.)
How each system works
12V low-voltage lighting
A transformer (also called a driver or power supply) plugs into a power point and steps 240V mains down to 12V. A cable runs from the transformer to each light, usually in a daisy chain, and the lights are LED fittings on spikes or fixed to walls. A timer or sensor on the transformer switches the whole system on at dusk. The lights themselves run at a much lower voltage than mains fittings, so the risk of a serious shock is lower, and the cable is lighter-duty and easier to run than mains cable. Follow the manufacturer instructions for how to lay and protect it.
Solar lighting
Each light is self-contained: a panel, a battery and a sensor in the one housing. No cable, no transformer, no power point. Whatever sunlight the panel catches today is what the light has to run on tonight.
Head to head
| Question | 12V low voltage | Solar |
|---|---|---|
| Brightness | Consistent, and can be strong enough for spotlights on large trees and walls. | Modest, varies with the day's sun. Best for accent and marker lighting. |
| Reliability in winter and shade | Unaffected. Runs on mains power. | Reduced in winter and shade. Panel position matters. |
| Install effort | Needs cable runs and a nearby outdoor power point. More digging. | Push in a stake or fix with two screws. |
| Control | One transformer, one timer or sensor, and you can add or dim zones. | Each light is independent. No central control. |
| Running cost | Small, mains electricity. | None. |
| Maintenance | Occasional connector checks and bulb or fitting replacement. | Clean panels, replace batteries over time. |
| Best for | Full garden schemes, large trees, long driveways, consistent look. | Quick improvements, hard-to-wire spots, renters, walls and fences. |
What really needs an electrician
This is the question people most often ask and the one it is easiest to get wrong, so be careful. In Australia, work on 240V mains wiring must be done by a licensed electrician. Rules differ between states and territories, so check with a licensed electrician or your state regulator for your situation. In broad terms:
- Solar lights. No electrician needed. They are self-contained and use a small battery.
- 12V lights with a plug-in transformer. The transformer plugs into an existing outdoor-rated power point and the 12V cable on the other side is generally treated as low-voltage work that a competent DIYer can carry out, following the manufacturer's instructions.
- Adding or moving a power point to supply the transformer, hard-wiring a transformer, or running 240V cable of any kind is electrician's work.
- Mains fittings such as a 240V floodlight or wall light also need a licensed electrician.
Buy the transformer and fittings from a reputable supplier and check for the Australian approval mark (RCM) on the plug-in power supply. Cheap transformers from unverified overseas listings may not be approved for sale or use here.
Where 12V is clearly better
- Large trees and big walls. A mains-powered spotlight is stronger and steadier than a solar one.
- Heavily shaded gardens. If your garden is under trees or on the south side of the house, solar panels will not fill their batteries.
- Long driveways and big blocks where you want even, switch-controlled lighting all night.
- A designed scheme. If you want zones, dimming or a consistent colour temperature across dozens of fittings, a 12V system is easier to control.
Where solar is clearly better
- A sunny wall, fence or path with no power point nearby. No cable, no digging.
- Finished gardens. Trenching through established beds, paving and lawn is the expensive part of a 12V job; solar avoids it.
- Renters and temporary lighting. Take it with you.
- Remote corners and back fences. Running cable to the end of a long garden is more work than the lights are worth.
A sensible hybrid
The best gardens often use both. Put the function lighting that has to work every night (the front door, the path from the street, the back step) on a mains or 12V system with a sensor. Use solar for the atmosphere: fence lines, garden edges, wall washes, feature planting. That way a cloudy week dims the ambience, not your ability to find the front door.
If you are building a sandstone wall or paving: plan the cable now
Cost and disruption of 12V lighting both come from digging. If you are about to build a sandstone retaining wall, lay a new path, or install sandstone pavers, this is the cheapest moment to put a length of conduit behind the wall or under the paving, even if you start with solar lights. A capped conduit costs very little before the backfill and a great deal after. Ask your landscaper or builder to leave it in, and have a licensed electrician advise on the power supply side if you want mains power at that location.
Thinking about cost
We have not put dollar figures on this comparison because they depend entirely on your garden, and any generic number would mislead. The pattern is consistent, though. A 12V system has a higher setup cost in cable, a transformer, a power point if you need one, and labour, and a lower per-light cost for brighter fittings. Solar has almost no setup cost and a modest per-light cost, but its lights are dimmer and their batteries need replacing eventually. Get a quote from a licensed electrician or lighting installer for the 12V option and compare it with the cost of a set of solar lights for the same area.
Decision guide
- Is the spot in decent sun for most of the day? If yes, solar is practical. If no, consider 12V.
- Do you need strong, steady light (a big tree, a security-like job)? If yes, mains or 12V.
- Is there an outdoor power point nearby, and is the ground easy to dig? If yes, 12V becomes realistic.
- Is the garden finished, or are you renting? Choose solar.
- Are you building walls or paving? Put in a conduit anyway.
Where to start
For the solar side of a scheme, see solar wall lights, solar path lights and solar spotlights, plus the job-specific kits on our lighting page. We do not currently sell 12V kits, so for that side of a scheme speak to a lighting supplier or licensed electrician.
Frequently asked questions
Can I convert solar lights to 12V later?
Not directly. They are different systems. But the positions you choose for solar lights are a useful plan for a future 12V layout, and a conduit left behind walls or under paving makes the later change much easier.
Will a 12V system add much to my power bill?
LED garden lighting uses little electricity, and a timer or sensor on the transformer keeps it to the hours you need. The running cost is small compared with the cost of installing it.
Do 12V lights work in a power outage?
No. The transformer needs mains power. Solar lights keep working in an outage because each one has its own battery.
Is 12V lighting safe in wet gardens?
The low voltage reduces the shock risk, but the transformer and connections still need to be weather-protected and the system installed to the manufacturer instructions. Use fittings with an IP rating suited to the location.