By Dave Miller· off-grid sparky · 22 years wiring solar, batteries and sheds in central QLD
“After blowing three cheap inverters, I learned that a 12V shed needs exactly 100Ah of lithium to survive a QLD winter without the lights flickering out.”
No fluff. Just how to get your off-grid lights working without wasting cash. We're talking real-world Aussie conditions.
No fluff. Just how to get your off-grid lights working without wasting cash. We're talking real-world Aussie conditions.
Room-by-room lighting plan sizing task, ambient and exterior circuits for a small off-grid home.
Fixture Types: Stop Buying the Wrong Stuff
Don't buy fancy LED globes for your shed. You need purpose-built solar lights. Here's the real deal:
Pathway lights: Cheap, basic, and useless for anything but stepping stones. Get the fixed type with a solar panel on top. Example: 400lm LED path light (not the 200lm "garden" kind).
Spotlights: For security. Must be weatherproof (IP65+) and have a wide beam. Don't use cheap "garden" spots – they die in a dust storm.
Task lights: For your kitchen or workshop. Needs high CRI (90+), bright, and dimmable. Skip the $20 "solar" lamp – it's garbage.
Emergency lights: Mandatory for off-grid homes. Must have 3+ hours backup. Don't skimp.
Placement: Don't Be a Dumb Aussie
Bad placement = wasted money. Here's how to do it right:
Panel placement: Must get 6+ hours of direct sun. No shade from trees. South-facing in the Northern Territory? Bullshit. North-facing for all of Australia. If it's shaded, you're wasting $200.
Light placement: Don't point lights at your house. Point them at the path or door. If you're lighting a 3m-wide path, you need one light every 3m. Not every 10m. Stupid.
Storage: Batteries need to be in a dry, shaded spot. Not under the eaves where it gets 50°C. If your battery dies in 6 months, you placed it wrong.
Brightness Calculation: Stop Guessing
Forget "bright" or "dim". You need lumens. Here's the formula:
Lumens needed = Area (m²) × 10
Example: Your 4m x 3m kitchen needs 120 lumens. But wait – solar lights lose 30% efficiency in winter. So you need 170 lumens minimum. Don't buy 150lm lights. You'll be fumbling in the dark.
Rule of thumb: 100lm = 1m² of light. 300lm = 3m². Simple. If your light says "1000lm" but it's a tiny bulb, it's lying. Check the actual output.
Practical tip: Test lights at dusk. If you can't read a newspaper at 8pm, it's too weak. Don't wait until winter to find out. Get it right first time.
Australian Suppliers & Pricing
Stop buying Chinese knock-offs on eBay. These are the only suppliers that work in Aussie conditions:
Solar Superstore (Sydney) – Best for path lights. $45–$75 for IP65 path lights (400lm). Get the fixed panel type, not the "solar garden" one. They have 3-year warranty.
Off Grid Solar (Brisbane) – Best for security. $180–$320 for 500lm spotlights (IP66). Includes 2-year warranty. Don't buy cheaper – they fail in dust storms.
Solar Direct (Perth) – Best for task lights. $120–$220 for 300lm+ CRI 90+ lights. Essential for kitchens. Skip the $50 "solar lamp" – it's useless.
Final Word
Don't buy the cheapest. Don't buy lights that don't say "IP65" or "400+ lumens". Get the right fixtures, place them right, calculate lumens properly. Then you'll have light that actually works. Not a $200 mistake.
⚠️ SAFETY WARNING: Working with electrical systems, structural modifications, or gas installations carries inherent risks. If you are not confident in your abilities, always engage a licensed professional.
He walks through his 12V battery bank, MPPT controller, and how he wires LED lights for his cabin, which is exactly the kind of practical setup I describe in the lighting design chapter.— Dave Miller
When to Call a Professional
While many off-grid projects are achievable as DIY, certain situations require licensed professionals:
Electrical work beyond basic 12V DC additions — requires a licensed electrician
Structural modifications to buildings or load-bearing elements
Gas line installation or modification
Solar array installations above safe voltage thresholds
Any work that affects the structural integrity of your property
Always check local regulations and obtain necessary permits before commencing work.