"should we be moving to configure domestic lighting circuits to 12v DC from the switchboard"

Wire the house like a caravan with 240v GPOs and 12v lighting.

Might be OK except for things like 500W bathroom radiant heaters that would need to go to the GPO circuit?

"should we be moving to configure domestic lighting circuits to 12v DC from the switchboard"

Like STC suggests having a 12V DC light supply could be a good move which one could take even further with a battery to keep things alight when the street mains fails.

Only downside would be a suitable battery as Lead acids would be out of the question as most users would most likely never look at them & large-ish NiMh are expensive with the best alternative being Lithium Iron (LiFePo4) cells with suitable battery protection circuitry. Have a 100Ah LiFePo4 battery in the camper & it runs rings around any type of Lead acid battery you care to name.

With many of the quite bright LED lamps taking <1A one could almost split the current 240V lighting circuit away from 240V & feed it with the 12V supply & not suffer any adverse volt drops.

At our previous residence where we were solar powered as no street mains for ages (initially) we had a 10Kva diesel genset which had inbuilt a start & generating winding of 32V DC which was all part of the excitation for the alternator.
This then supplied us with a neat lighting solution being 32V and I did just what I said above I split the 240V lighting circuit onto a separate small switchboard using 32V DC fed from the shed. We were able to take around 15A from that supply with upsetting the AC regulation.

All house power points were 240V AC & all lighting was DC powered 32V & then 32V globes were easy to source.

This saved us from running a twin cylinder diesel setup driving a 10Kva alternator when we just needed lights which was then added to with a 32V inverter supply 240v 50Hz to the house when the genset was idle so loads up to 300W could be powered from 240V via the inverter. Once the genset was started there was a Changeover contactor in the AC feed which dropped off the inverter & fed the AC to the house.

Then solar power came along with bigger batteries & inverters so that took over most of the work from the genset & it remained like that until we got a reasonable connect cost to join the scheme that had finally worked its way down our road so the genset got pensioned off & the solar became our standby source.
Being semi rural the standby source was often utilised as the slightest sniff of lightning would cause the feeder to fail.

Lindsay

Although 12 volts is almost ubiquitous, I think 24 DC volts would be a better choice for cabling a modern house's lighting.

Just remember, if the dwelling is still connected to the mains the installation still needs to meet the requirements of AS3000 (SAA Wiring Rules). A licenced electrician is still required to carry out any work on fixed wiring too.

‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

One thing about LED bulbs is that it is always the switch mode power supply that fails, not the LEDs themselves, so don't throw them out. Certainly return them to the store if they have stopped working in a couple of years. If you stand your ground, they have to replace or refund. Failing that, salvage the LEDs themselves, they are very useful.

On another subject mentioned in this topic, human induced climate change is very real, and terrifying. I know, I have studied it at University level. You can't ignore basic physics.

Cheers, Stuart

Yes, look at those graphs of atmospheric CO2 and temperature over the last 10,000 years. The sharp, almost vertical kick-up on the right hand side is scary and alarming.

As it was said , trees are the lungs of the planet. We keep clearing them for buildings and farming and its going to be harder to breath.

QUOTE: trees are the lungs of the planet.

Plankton that does photosynthesis in the oceans does a lot of this work as well.

Ever wonder why, if LED globes are so efficient, why they'd need heat sinks?

And the LEDs I hear are organic, does that mean they're made without pesticides? (running, ducking for cover)

The heat sinks are mainly for the current sources and the LED bulk resistance.

"Organic" means carbon-based, to me.

"Plankton that does photosynthesis in the oceans does a lot of this work as well."

Rising CO2 levels are also lowering the pH of the ocean, making it more acidic. This makes it more difficult for marine life to fix calcium for shells and for coral to make calcium carbonate. This has the potential to threaten the present marine ecosystem.

Regarding climate change, I am not convinced that the end of the world is nigh. The world's climate has been under constant change for 4.5bn years and whilst there's been very hot times and some very cold times the planet's always managed to sort itself out, although I'd agree that this has probably been a fluke each and every time.

Regarding the efficiency of LED globes, they are certainly more efficient than incandescent globes but there's nothing that is 100% efficient. All electrical loads give off heat and that includes wiring. The place I work at has three underground substation transformers. Two in use and one as a spare. Off each in-use one there is a 3,000A load and the heat given off by both the transformers and the cabling in the adjacent switch room is amazing, despite all being in spec with nothing at risk of overheating.

As far as cost goes, I'd be more worried about the total power consumption of a globe rather than its efficiency. In other words, go for cost efficiency rather than electrical efficiency. That said, if a 14 watt 'four footer' was pulling 50 watts, I'd be a bit miffed about it. Stick to the big brands - Philips, etc.

‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

My house has always had tube fluoro ceiling lights, so the ban on standard tungsten bulbs wasn't a problem, I just stocked up on these. I did use halogen for a while in my desk lamp, but they don't seem to last very long, and are vulnerable to bumps. I couldn't use CFLs because of the bad colour, and stuck with daylight (blue tinted) standard tungsten for drawing. Now these are unavailable, so I'm trying the white plastic LED bulbs. So far so good. The "retro" LED filament bulbs are nice for spot lighting, but the light is candle yellow. I wish they'd make them in a higher colour temperature. I'd stop grumbling about modern lighting then!

Hi Sue agree with you absolutely I have fluro tubes in most rooms where you actually want to see what you are doing, some 2 foot twins and some 3 foot twins. Why people want to grope around in the dark with tiny little candles is beyond me or maybe my eyes are getting old!
Some fluros in my workshop are 30 to 40 years old and still work with enough light not to need replacing. They are the large diameter type and will see me out. We only have globes (old 100watt) in the short term use rooms like the laundry, bathroom for instance. Also helps that I have most walls and ceilings WHITE painted not trendy black or blue. Reflection is king!
As for the idiots getting rid of old school globes, they make a globe made of a bit of tin and glass illegal but allow a globe full of rare metals, poisonous gasses and a bit of glass legal and that is going to save the planet?
Idiots!
Fred.

Something to be considered: Stemming from being a carer I actually came to the realisation that Exit lights had potential. I still think using NiCd batteries in them is criminal, however.

What I did in the previous house, was strategically place one next to a door as normal, without its screen and the telephone below it. So you could actually hang on the phone & be outside. Because the bathroom door was rarely shut another (non-monitored) one was in the hallway. Mum could see with it without running around looking for a torch, or switch in the dark.

What happened one night while elderly mum was in the shower, lightning took out the power. Of course there was enough light instantly from the hall exit light to see and get out of the situation. The building I am in at the moment has one as it has no windows only a door: Telephone at the door. I also have one in the living area of the house in a position where it looks down the hall & is over a door.

No need to run around looking for candles & torches. Most of these now are LED. Non monitored is the one that is off until such time as it looses mains supply.

Marc

All new exit lights (Stanilite brand) now run on a LED globe, or rather a permanent LED module rather than a globe or tube. This means when the LEDs are no longer glowing you simply replace the whole fitting rather than the source of the light itself. To me, this is more of what should be banned by the government than choice of light source but as we all know, industry gets away with everything these days.
All electrical lighting manufacturers simply say it's not economical to produce any luminaire with the ability to replace a standard lamp as once was. This is BS. What they are worried about is the bottom line, ie: profit, and there is a big difference between viability and profit.

In their favour (and Stanilite was first to do this) most brands of exit light fittings in Australia clip in to a hard wired bracket now rather than the fitting itself being hard wired and this makes replacement something that anyone can do provided the same brand is used each time, as the brackets are a different form factor with each brand. Stanilite uses the same bracket they devised about 30 years ago though, which is good.

On the subject of exit lighting, and with the increasing number of blackout situations we'll all ultimately suffer with this stupid move away from coal-fired generation, there is a fitting nicknamed a 'spitfire' which is an emergency light fitting that works a bit like an exit light. It is quite small, LED-equipped and will run for about four hours after the power is lost and simply recharges once the power is restored. If anyone is worried about elderly relatives being without light, these fittings are worth considering. They come with a power cord so they don't have to be installed by a licenced electrician, though unless the user has a GPO in their roof space then a GPO or surface socket would need to be installed by an electrician.

http://new.abb.com/low-voltage/products/lighting-emergency-lighting/emergency-lighting/stanilite/highlights/economy-spitfire-led-recessed

The main reason NiCads are still used is economics. It doesn't cost much to make them and they still do the job.

‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...