Reduce Lighting Bills To Just Cents A Day With LED
Last Updated: 8th Jan 2025 By Finn Peacock, Chartered Electrical Engineer
When I started writing about energy efficiency way back in 2008, the first piece of advice I doled out was this: “Changing your globes should actually be a low priority compared to other energy efficiency measures you can take.”
Say what?!
Well, the thing is energy consumption surveys indicate lighting accounts for just 7% of an average Australian home’s energy use. The incandescent alternative – low energy CFL globes – available at the time were expensive, ugly, some cast a horrid light and often didn’t last as long as promised.
This meant that if you replaced all your globes in 2008, you’d typically shave about 5% off your bill. Not bad, I suppose. But my concern was that the low-quality light and small savings might actually discourage you and put you off energy efficiency for life; and we can’t have that! Two things have changed over the past 16 years that have completely reversed my advice. Those things are:
- Halogen downlights
- Huge improvements in LED lighting technology
Halogen Downlights Are Evil
It is exceedingly rare to find a new or renovated home that does not use recessed downlights for some or most of its lighting. People like the look of them, and it seems like they are here to stay.
But the thing about downlights is it takes a hell of a lot of them to light a room, and standard halogens are almost criminally inefficient power guzzlers.
If you want proof of this, go and find one and touch it. If it has been on for more than about 60 seconds, it will be insanely hot. That tells you that most of the electricity going into the sucker is being converted into heat instead of light. Not good. Combine that with the fact that homes and rooms are generally getting larger, and the result is that lighting energy as a proportion of residential energy use can go through the roof.
From the data I can pull together, thanks to halogen downlights, an Australian home can use up to 30% of its power for lighting. For a 4+ person home that is a whopping 7kWh per day. That means that if your home has halogen downlights, you need to consider replacing them if you are to have any hope of smaller electricity bills.
Thankfully, halogen and incandescent light bulbs have/are being phased out from the Australian market, where an LED equivalent is available. And luckily, getting your lighting bills down by 80-90% can be cheap and easy, and you don’t have to sacrifice the quality or brightness of the light anymore. I’m amazed anyone has any of those evil little halogen globes in 2025. If you still have any, track them down and terminate them with extreme prejudice.
LED Technology To The Rescue
LED technology is now so good and so cost-effective that I strongly believe you are wasting your money buying any other technology to light your home. Forget so-called ‘eco halogens’, forget those ugly, compact fluorescent lamps (CFL), which are going the way of the dodo anyway. LEDs are the answer. Simple as that.
Here’s why I love LEDs:
- Typically 85-90% power reduction compared to incandescents.
- Lovely warm light indistinguishable from the warm glow of an incandescent bulb to my eyes. But you can also get “cool” LED lights if that’s what you prefer.
- They will last 10,000 to 20,000 hours.
- You can get an LED bulb to replace practically any style of globe you can think of.
Tip: Be wary of buying a LED that says “Cool White”. Although everyone has their personal tastes, I personally can’t bear the cold white light of “cool white” bulbs. I always check that the light is “Warm white”.
Here’s a very simple illustration of the incredible payback of LED technology. Let’s look at replacing a typical kitchen’s 6 halogen downlights (rated 50W each) with good quality 7W LEDs.
A survey of lighting use in Australia shows that the average kitchen/living area light is on for 6.4 hours per day. Those 6 evil little 50W halogen bulbs are going to use 6 x 50W x 6.4hrs x 365 days = 700kWh per year. Based on 34c per kWh, that’s $238 per year.
But 6 LED bulbs will only use about $33 worth of electricity per year. So you are saving $205 per year. If the 6 LED downlights cost $15 bucks each, then you will get back your $90 outlay in less than 6 months. That’s an excellent return on investment.
Where Should You Start With LED Lighting?
The 2 golden rules I always follow with energy efficiency projects are these:
- Target the best payback first.
- Buy good quality replacements that will last, or it’s all a waste of time and money.
To target your LED spend wisely, don’t feel the need to do every last light in your home straight away. Remember the old 80/20 rule? It tells us this: 80% of your lighting energy will be guzzled by only 20% of your globes. So let’s find the critical 20% of globes that you should replace first.
In the lighting survey I mentioned earlier, it indicated 80% of lighting energy is used for kitchen/living, bathroom, and outside lighting. So if you replace all those globes first, then you’ll solve 80% of the problem!
But let’s start even smaller. Let’s begin with the rooms that use by far the most lighting energy; the kitchen/living areas.
Replacing the lights here can give us that magic less than 6 months payback. Let’s do it! Like right now! What else can you do so quickly that will give such a good return? Seriously, if you can save $200 per year over the next 10 years with such little effort, that’s got to be worth it.
Simplest Way To Get The Right LEDs For Your Home
I don’t know about you, but back in the days before I went to 100% LED lighting and I had globes that needed replacement, I went to my local supermarket to get them. But which ones should you buy? What wattage? What style? What fitting? Are they good quality? Is it an GU5.3 or a GU10 downlight? Which ones cast a nice light at the right angle? And will the transformers in your ceiling be compatible?
As with solar, there is a lot of junk being sold in the Australian LED industry. I’ve seen lots of cheap LED lights with insufficient heatsinks. This means they will overheat. When an LED overheats, it gets dimmer, and its life will shorten dramatically. It is critical to buy good quality LEDs. The best place in Australia to buy replacement LEDs in my humble opinion is Reduction Revolution. I say that not because they are paying me (they aren’t!) but because I trust them to only stock good quality LEDs, and their advice is excellent.
Choosing An LED Downlight To Replace A Halogen
LED downlights are easy to replace. There is no need for an electrician, unless you need to replace the transformer, which is unlikely. Your downlights will either be “GU5.3” or “GU10”. To find out what they are, simply remove one and compare it to this picture:
My Favourite LED Downlights
Years ago, I replaced 29 halogen downlights. For the non-dimmable LEDs I used the Philips Master LED MR16 (GU5.3) 5.5W. At the time of writing these are only $13.90 each and usually cheaper if you buy them in multi-packs. They are amazing. The light output is as good as any downlight (LED or halogen) that I’ve seen.
For the dimmable LEDs, I used the more expensive Philips Master LED MR16 (GU5.3) 7W Dimmable. These days, the 7.5W versions are around $22.95; again, cheaper in a multi-pack.
If you can replace all your non-dimmable 50W halogens with LEDs, it has to be the best energy efficiency upgrade you can do. I urge you to replace those nasty halogens right now!
A Note For Solar Power System Owners
If you have solar panels installed on your rooftop, then having the most efficient lighting possible is a top priority. Why? Because you usually switch your lights on when the sun goes down, and all the electricity powering those gazillion downlights is coming from the grid at 30c+ per kWh – unless you have a home battery. And as you know, the secret to a low bill with solar power is using as little energy as possible when your panels aren’t producing. That makes LEDs the perfect complement to a solar energy system.