The energy solution for South Africa is DC power.

[Swa]

Stop talking BS> You claimed that a home can be converted to 12VDC by using the existing electrical wiring in situ as the wire can handle double the current using DC as opposed to using 220V AC. You punted it was due to the skin effect on copper using the 220V AC. I have shown and proven to you it's absolute horseschit as for a 360Watt appliance you need a 7.5mm diam wire for the load you claimed. With 220V AC the calculated load is closer to 3KW. I also showed you that at 50 HZ there is no skin effect to be concerned of with 2.5 mm2 standard home wiring.

As usual you make claims and as you get caught out you alter your story by thumbsucking more BS and then talk in circular arguments to try and convince others that you had a different meaning. Now you claim that the idea was to cut out all high power devices, like computers, Hifi's, Surround sound systems, hair dryers, etc..

So lets go camping at home and lets cut out all conveniences. At the same time only plug in one device with wattage far less than 360Watt at any one time. The rest of the family must queue in line to use their conveniencies or appliances.

That makes someone doing it a blatant liar in my books! Thats a trait all conman and politicians use very well. Spin Doctor extraordinaire.

By the way I have used your own example of 360Watt to prove to you your whole argument and claim is a total fallacy.

I claimed that the standard wiring can be used for 12VDC. Your straw men and red herrings aside that is still correct. I said multiple times it's for low power applications so they don't prove it inviable. The OP even mentions low cost housing so a tv and a few lights perhaps a cellphone charger is it. You still don't seem to understand the 360W example. It's the limit of what I would consider viable and not necessarily practical but you seem to be treating it as a starting point. It's interesting that the examples can use anything from 9-18V.

As for your high power examples, it was mentioned long ago already that higher voltage DC is a solution so you haven't presented any facts against it.

Strange that over many threads you kept on asking why those batteries are not available locally sort of punting them as total solution . Now you yourself argue against their claimed performance specifications and questions how safe they are and punting another battery which are manufactured using pill box equipment as total solution even after I showed you they claim it could not handle deep cycling at all. Oh, yeah they shipped 100 units according to the info you supplied)

BTW I found a local supplier with LiFePO4 batteries in stock. A total solution.

I asked a simple question. I am not arguing against their safety but quite the opposite. They are VERY safe considering the large amount in use. Their performance specifications are quite good compared to lead-acid and VRLA but I won't delude myself into believing they are near perfect. The "pill-box" batteries I mentioned are even safer, more long lasting and has better deep cycling. I am not punting any total solution as there are none but these are certainly an interesting area to keep an eye on. One step closer to home made and serviced solutions. For now I am just watching all the tech fighting it out.

PS: Not even your God can understand you or your motives, no wonder everyone hates your posts in PD, Christians alike.

Still with the massive sense of ego I see thinking that you are everyone.

Quiet a few misconceptions in there again. Sure the efficiency of the older type AC to DC power supplies was low due to the bulky size of the components to handle the heat to account for the voltage drop from 220VAC to DC. In general transformers were used with linear electronics. In modern day times that is not the case and efficiencies of high in the nineties can be achieved (as high as 97%+) by using high frequency Switch Mode Power Supplies. SMPS. (Google some and learn) There are no way you can get the same efficiencies going 12VDC-AC or DC-DC as you would get using AC-DC with SMPS. (To know why google some more) If you really know how a computer PC Supply works you will understand.

Let me enlighten you a bit. Most power supplies are still linear so they are bulky and waste a lot of energy. Even most PC SMPS are nearer to 80% efficiency. The green ones are in the region of 90% efficiency. You're going to have to pay through your nose for 95% efficiency and I doubt you'll readily even get 97%. It's not worth it for solar power and most probably not even for grid power.

If you know the real world figures you'll know DC-AC-DC is optimistically 80% efficient making it a good yardstick for pure DC.

Here again you are trying to deflect from reality. Converting from 220VAC to DC direct have very small losses by just rectifying 220VAC to 400V DC as a DC bus, this immediately gives you the required level of DC for most consumer appliances. Then using SMPS to convert that 400VDC to any other xDC voltage can be achieved easily with small components that can be very efficiently done with SMPS designs which size is fairly easily scaled depending on the load required. Therefore the reason rather use 220VAC as home reticulation on standard 2.5MM2 wire and convert the 220VAC to 5VDC with an SMPS which a simple and effective solution directly at the point where the load is required; like charging your cell phone in your bedroom. Thus 220VAC low amps in 5VDC higher amps out at 97% efficiency. If you want to do that using direct 12V DC you will not get the same efficiency as the DC-DC conversion will be less efficient and the phone charger larger depending how you do it all depending on the electronics design and whether its digital or linear electronics in the design. If you go direct to 12VDC you will have to use thicker wire as I have shown you numerous times based on the load required. A simple 360Watt appliance or device will require a 7MM dia or 33MM2 wire to operate. Thats for one device. Totally impractical and illogical for a home dwelling.



Again you detract from your original claims that an existing home can be converted to 12VDC without major rewiring and without any current or wattage limitations in fact you claimed you can double up the amperage in the standard 2.5mm2 home wire circuits using 12VDC instead of the 220VAC which was proven and shown to you as absolute garbage.

Again your red herring of high power low voltage DC (not what was claimed) is deflecting from the reality that DC-AC-DC is 80% efficient being optimistic. DC-DC conversion is at least as efficient as AC-DC using SMPS.

Another lie, this is becoming so standard for you even in the PD sections. I was shown to you that the choice Isheed_cn made to use a 600V high power solar panels instead of 12VDC was based on sound engineering principles by expert companies as a standard. One of their main reasons was to save on installation costs as it is clear and proven to you that sending high voltage DC at high loads to supply a complete dwelling with the required power(watts) requires thinner and cheaper copper cables than supplying the same power (watts) for that same distance at 12VDC.

You like making accusations without substantiating them? That seems to be a standard for you. I showed you sound physics proving that 600V vs 240V (not 12V) only yields a saving of R45 in solar panel. So you are falling for marketing hype and using the argument from authority to try and justify more expensive equipment and cable. I have that bridge ready for you.

Your fallacy argument to solve the problem was that everyone should wait until new appliances are designed that will cut out these high power appliances we use and wait for the world to design low power appliances that works directly of 12VDC and legislation must be changed. You randomly googled for such appliances like your 12V DC PC supplies and i showed you they are expensive to buy, expensive to add the required 12VDC 33MM2 or 7mm diameter wiring required which would require civil mods to route the cable and that the current standard 2.5mm2 home wiring can not accommodate the load amps required at 12VDC. Then you thumsucked another few arguments to counter that saying low power devices and thus advising laptops as the solution.

You keep on changing the goalposts.

You are coming up with fallacies and changing the goalposts. I never claimed that high power devices should become low power devices. I repeatedly said more support for low power devices. We are seeing that support right now.

 

[russellw1]

I use 12v LED downlights because I don't get inverter losses and it also means less work for the UPS units I use on the tv and decoder and it is usefull to have light to start the generator at night.

 

[russellw1]

As an electronics technician I know that there is no skin effect ar low frequency 50 Hz, It starts to happen at sort wavelengths in the cm range.

 

[T-Man]

Found this nice calculator to determine voltage drop.

http://photovoltaic-software.com/DC_AC_drop_voltage_energy_losses_calculator.php

I just put in a quick calculation comparing 2 solar panels in serial vs parallel. Scary how much more you lose at 36.6V vs 73.2V.
The thickness of the cable plays a role as well - 4mm2 vs 6mm2 vs 10mm2.

 

[Swa]

Found this nice calculator to determine voltage drop.

http://photovoltaic-software.com/DC_AC_drop_voltage_energy_losses_calculator.php

I just put in a quick calculation comparing 2 solar panels in serial vs parallel. Scary how much more you lose at 36.6V vs 73.2V.
The thickness of the cable plays a role as well - 4mm2 vs 6mm2 vs 10mm2.

Yes but don't go overboard as well. There's no reason to go 600V with special cabling when 300V will prove more economical with standard wiring. I wouldn't go past 120V for safety reasons.

 

[ToxicBunny]

Are you still banging this damn drum with your BS?

 

[Seriously]

Found this nice calculator to determine voltage drop.

http://photovoltaic-software.com/DC_AC_drop_voltage_energy_losses_calculator.php

I just put in a quick calculation comparing 2 solar panels in serial vs parallel. Scary how much more you lose at 36.6V vs 73.2V.
The thickness of the cable plays a role as well - 4mm2 vs 6mm2 vs 10mm2.

You cannot argue against an person with circular arguments changing the claims and stories all the time. We all stated the same facts it but he is too obtuse to accept the proven calculations presented to him. He just cannot understand the difference in cable cost and the DC losses incurred because of the resistance of copper cable at lower DC voltages so let the .... be.

Sarcasm on:

Off course the volt drop is due to the source and not due to cable resistance as he claimed and you get double the amperage capacity on the same 2.5mm2 home wiring when using DC as opposed to be using AC. You can use 360W at 30 amps at 12VDC through the standard 2.5mm2 home wire according to his scientific claims. Everyone else is talking BS. DC is the future of power distribution and reticulation as we are now in the era of DC, AC have run it's cause and is not the future anymore. Just the whole world will have to adapt to this new concept and every consumer must do away with their conveniences and start camping in their own homes. No more hair dryers, fridges, etc. Thats the future and new era according to Swa.

/sarcasm.

He has to ask himself why everyone with the knowhow and/or experience left this thread. Simply because there is no point debating logic with an total imbecile.

 

[Seriously]

Yes but don't go overboard as well. There's no reason to go 600V with special cabling when 300V will prove more economical with standard wiring. I wouldn't go past 120V for safety reasons.

Lets look at this idiotic argument again.
600VDC 1800W 3amps 2.5mm2 wire 10meter 0.55volt drop 1.66watt loss energy loss 0.1%
120VDC 1800W 15A 2.5mm2 wire 10meter 2.76volt drop 41.4watt loss energy loss 2.3%
120VDC 1800W 15A 50mm2 wire 10meter 0.14volt drop 2.1watt loss energy loss 0.11%

Real life situation for Isheed_cn

600VDC 4800W 8amps 2.5mm2 wire 20meter 2.94V drop 23.55W loss energy loss 0.49%
600VDC 4800W 8amps 10mm2 wire 20meter 0.74V drop 5.8W loss energy loss 0.12%

300VDC 4800W 16amps 2.5mm2 wire 20meter 5.89V drop 94.21W loss energy loss 1.96%
300VDC 4800W 16amps 10mm2 wire 20meter 0.74V drop 23.55w loss energy loss 0.49%

120VDC 4800W 40amps 2.5mm2 wire 20meter 14.72 drop 588.8W loss energy loss 12.3% Standard wire will overheat and fail!
120VDC 4800W 40amps 70mm2 wire 20meter 14.72 drop 588.8W loss energy loss 2.45%

Thus even with a 70MM2 copper wire the energy loss would be 21W at 0.44% still more than the 600VDC calculation.

Yet Swa claimed previously that the cost difference would have been only R45.00. I want to see at which supplier the copper price difference between 2.5mm2 and 10mm2 is only R45.00.

He also now claims that he would not go above 120VDC for safety reasons. Must be because I raised the concern about the 600VDC earlier in this thread but then he debunked even that concern at the time, now suddenly it's a concern for him too! So much for the idiotic circular reasoning!

 

[Sonic2k]

As an electronics technician I know that there is no skin effect ar low frequency 50 Hz, It starts to happen at sort wavelengths in the cm range.

Not quite.
It is there, ask Eskom. It is a cause of some losses on the EHT transmission lines.

It has also been a problem in SMPS design, ever wondered why the car amplifier and computer PSU uses litz wire for the transformer secondary winding that supplies the main 5V rail to the CPU and GPU?

My best advice is to stop feeding the troll (OP). I had to deal with his kind at my previous job, I left it to get away from his kind. They will run you ragged in the process, just like William Preece did back in the day with Marconi.

Here again you are trying to deflect from reality. Converting from 220VAC to DC direct have very small losses by just rectifying 220VAC to 400V DC as a DC bus, this immediately gives you the required level of DC for most consumer appliances. Then using SMPS to convert that 400VDC to any other xDC voltage can be achieved easily with small components that can be very efficiently done with SMPS designs which size is fairly easily scaled depending on the load required. Therefore the reason rather use 220VAC as home reticulation on standard 2.5MM2 wire and convert the 220VAC to 5VDC with an SMPS which a simple and effective solution directly at the point where the load is required; like charging your cell phone in your bedroom. Thus 220VAC low amps in 5VDC higher amps out at 97% efficiency. If you want to do that using direct 12V DC you will not get the same efficiency as the DC-DC conversion will be less efficient and the phone charger larger depending how you do it all depending on the electronics design and whether its digital or linear electronics in the design. If you go direct to 12VDC you will have to use thicker wire as I have shown you numerous times based on the load required. A simple 360Watt appliance or device will require a 7MM dia or 33MM2 wire to operate. Thats for one device. Totally impractical and illogical for a home dwelling.

This person is correct.
Can you imagine trying to run a TV from 12V DC...
So we rectify the mains and get a nominal 325V DC, already we have a nice supply rail that we can conveniently switch down to lower voltages at nice powerful currents with amazing efficiency.

Here is my best example.
I have a client, who runs a desktop PC in a BUS. Bus has 24VDC battery.
Do you know, that the power supply to do that, is FOUR TIMES THE SIZE of a normal PC power supply and can only handle 250W. They cannot expand the system because they cannot add a graphics card, the power supply won't handle it. And, while we are at it, the input cable to this power supply is nearly 16mm2 thick! That is like 16mm2 versus 2.5mm2 for the normal kettle cord on the back of the PC.

 

[Swa]

You cannot argue against an person with circular arguments changing the claims and stories all the time. We all stated the same facts it but he is too obtuse to accept the proven calculations presented to him. He just cannot understand the difference in cable cost and the DC losses incurred because of the resistance of copper cable at lower DC voltages so let the .... be.

Do you even read what people post?

Sarcasm on:

I'm glad you're treating it as sarcasm now and no longer think your claims are reality.

Lets look at this idiotic argument again.
600VDC 1800W 3amps 2.5mm2 wire 10meter 0.55volt drop 1.66watt loss energy loss 0.1%
120VDC 1800W 15A 2.5mm2 wire 10meter 2.76volt drop 41.4watt loss energy loss 2.3%
120VDC 1800W 15A 50mm2 wire 10meter 0.14volt drop 2.1watt loss energy loss 0.11%

Real life situation for Isheed_cn

600VDC 4800W 8amps 2.5mm2 wire 20meter 2.94V drop 23.55W loss energy loss 0.49%
600VDC 4800W 8amps 10mm2 wire 20meter 0.74V drop 5.8W loss energy loss 0.12%

300VDC 4800W 16amps 2.5mm2 wire 20meter 5.89V drop 94.21W loss energy loss 1.96%
300VDC 4800W 16amps 10mm2 wire 20meter 0.74V drop 23.55w loss energy loss 0.49%

120VDC 4800W 40amps 2.5mm2 wire 20meter 14.72 drop 588.8W loss energy loss 12.3% Standard wire will overheat and fail!
120VDC 4800W 40amps 70mm2 wire 20meter 14.72 drop 588.8W loss energy loss 2.45%

Thus even with a 70MM2 copper wire the energy loss would be 21W at 0.44% still more than the 600VDC calculation.

Yet Swa claimed previously that the cost difference would have been only R45.00. I want to see at which supplier the copper price difference between 2.5mm2 and 10mm2 is only R45.00.

Alas still busy concocting straw men I see.

He also now claims that he would not go above 120VDC for safety reasons. Must be because I raised the concern about the 600VDC earlier in this thread but then he debunked even that concern at the time, now suddenly it's a concern for him too! So much for the idiotic circular reasoning!

Your fallacies and backtracking seems to know no bounds. You never raised concern about 600VDC and in fact endorsed it like you are here.

This person is correct.
Can you imagine trying to run a TV from 12V DC...
So we rectify the mains and get a nominal 325V DC, already we have a nice supply rail that we can conveniently switch down to lower voltages at nice powerful currents with amazing efficiency.

You do realise that converting it into that AC supply is what's making the efficiency abysmal?

 

[Seriously]

This person is correct.

Can you imagine trying to run a TV from 12V DC...
So we rectify the mains and get a nominal 325V DC, already we have a nice supply rail that we can conveniently switch down to lower voltages at nice powerful currents with amazing efficiency.

You do realise that converting it into that AC supply is what's making the efficiency abysmal?

Again sidestepping reality and fact with a BS comment without substantiating his claims.

The heat losses by using 12VDC over copper cable due to the copper cable resistance (I2R) in the home environment will far exceed the unsubstantiated "abysmal" efficiency losses Swa is referring to who's claiming that 12VDC reticulation its the total solution which is absolute poppycock BS. if you use a modern inverter to invert the stored solar energy 12/24/48/DC voltage to 220VAC. The cost savings in copper cable alone will pave a long way in paying for inverter. The benefits of not having to forgo of all the consumer devices in a normal home working of 220Vac and considering no appliances needs to be replaced also play a big role. Swa went from a 12VDC concept to a 220VAC/12VDC concept to a 110VDC concept and only god knows what else he dreamed up as he jumps to new ideas from post to post! Just read all his responses to people that actually know what they were talking about. All the "Straw men" calculations have proven him wrong yet he insists on 12VDC as the solution as long as you forgo of all modern conveniences.

Who wants to be camping in their homes? Not me for sure.

 

[Seriously]

Do you even read what people post?

Lets see who can read:

Isheed_cn stated he used a 600v DC cable from his high power solar panels to his battery bank charger. See the resulting Swa responses re the 600V saga..

I have a 20 metre run of single strand @ 600V in my house from my DC side (solar 36v * 16 @ 8A). My cable is UL rated for 1000v. Its a lot more expensive than any other cable in the house.

Actually the 600v was chosen by myself when I designed my solar setup
My inverter works from 250v-1000vDC

. People like lsheed_cn who thinks that he should rewire his entire house for 600VDC when 110V will be more than sufficient for any application. Then use expensive single strand wire because of the skin effect. The skin effect is something that applies to AC exclusively. Ordinary house wiring can handle about twice the current as well under DC

Please note Nowhere did Isdeed_cn imply his complete house is to be converted to 600VDC. Swa just used it to debunk reality as usual. Thats his style.

Even after I posted manufacturers design details and justification he still insisted with his FUD.

He even tried his best to make lsheed_cn look incompetent referring to the question of the 600VDC feed cable from his solar system to the 600V charge controllers then later claimed lsheed_cn was not clear yet he never discussed or asked questions and just made up his own design in his head. The 600VDC was engineered by experts to reduce the required cable size from the solar panel to the battery charge circuits …. See example http://www.solar-electric.com/xaxwmp80amp6.html with their comment.

When dealing with very high power solar arrays, wire size and the distance from the charge controller are critical design elements. The 600 volts DC input limit allows for a higher string voltage and and overall higher system efficiency. This model is perfect when your solar array must be mounted far away from the charge controller. If you simply configure your array for a higher voltage, you can deliver the power to the controller using a smaller wire size. When you consider the cost savings by using a smaller wire size, this controller may end up saving you a substantial amount of money on installation. This controller may also be used to charge batteries from high voltage grid tie arrays

Now the claimant want to give the Impression that these experts knows nothing and with a 12VDC panel he will achieve the same. C'mon...who is he bluffing other than himself and those readers that do not know better. From there the stored battery power will be converted to 220 VAC via Inverter circuits. Yes the real experts use inverter circuits to produce the power required for the various appliances in the home simply because it’s the best solution to save on copper cable installation costs. Also the use of existing cost effective appliances already owned or in stock at retailers may be used instead of non existing or very expensive DC systems. Have anyone got or used a 12 volt hair dryer yet? Ignore the twaddle some are trying to sell you.

I rest my case!

I'm glad you're treating it as sarcasm now and no longer think your claims are reality.

Those was all some of your arguments and fallacy claims still unsubstantiated all in one go. Luckily everyone saw through your BS in this thread just as they do in PD.

Alas still busy concocting straw men I see.

Since you realised you were caught out with your own circular lying thumbsuck BS thats the most intelligent comment you could come up with in defense of your BS?

Your fallacies and backtracking seems to know no bounds. You never raised concern about 600VDC and in fact endorsed it like you are here.

High voltage DC in a home environment? Lethal as accidents will happen.

You do realise that converting it into that AC supply is what's making the efficiency abysmal?

poppycock BS as usual

There ya go!

 

[Swa]

Again sidestepping reality and fact with a BS comment without substantiating his claims.

The heat losses by using 12VDC over copper cable due to the copper cable resistance (I2R) in the home environment will far exceed the unsubstantiated "abysmal" efficiency losses Swa is referring to who's claiming that 12VDC reticulation its the total solution which is absolute poppycock BS. if you use a modern inverter to invert the stored solar energy 12/24/48/DC voltage to 220VAC. The cost savings in copper cable alone will pave a long way in paying for inverter.

You are still sidestepping the arguments with garbage "facts and figures." As has been said for the umpteenth time now 12V was never proposed as a total solution. You are the one claiming it's inviable because it isn't a total solution which you still don't understand to be your straw man. As for your 220VAC inverter solution, you still haven't answered to the fact that your efficiency is 80% if we're being realistic.

The benefits of not having to forgo of all the consumer devices in a normal home working of 220Vac and considering no appliances needs to be replaced also play a big role.

Nobody said anything about forgoing anything. Again another made up straw man by you.

Swa went from a 12VDC concept to a 220VAC/12VDC concept to a 110VDC concept and only god knows what else he dreamed up as he jumps to new ideas from post to post! Just read all his responses to people that actually know what they were talking about. All the "Straw men" calculations have proven him wrong yet he insists on 12VDC as the solution as long as you forgo of all modern conveniences.

Also your straw man. The concept was 240VAC/12VDC from the start and possibly moving to 110VDC stepped down to 12V for low power devices. It seems your in the box thinking doesn't understand the concept of multiple possible solutions. You still haven't shown DC to be inviable.

There ya go!

Not even going to try and decipher all that. Let's put this crap to rest. The 3840W was in reference to your example outputting a maximum of 80A @ 48V. I showed you the calculations coming out to a mere R45 saving in solar panel even at voltages as low as 240V for your example. You are still unable to justify that with the increased wiring and equipment cost. Glad you're resting your case on that.

I have a 20 metre run of single strand @ 600V in my house from my DC side (solar 36v * 16 @ 8A). My cable is UL rated for 1000v. Its a lot more expensive than any other cable in the house.

This doesn't even imply converting his house to 600V to you? You got to be kidding. In any case I've put that down to a simple misunderstanding. I don't know why you can't get over it.

I repeat this again: You never raised concern about the 600VDC and in fact endorsed it like you still are. Your BS concern was for the home environment which I showed you was the real poppycock.

 

[richjdavies]

Every now and then I come back to this thread for a little bit of troll watching. It's fun This is my trool-zoo...

Here's my little food packet for the hungry monsters:
[BTW - from what I can tell, we're going with several DC-DC step up and down transformers for each device in the home, rather than one inverter... is that the plan? or are we sticking with one massive busbar running at 12V through the ceiling void?]

 

[ToxicBunny]

Every now and then I come back to this thread for a little bit of troll watching. It's fun This is my trool-zoo...

Here's my little food packet for the hungry monsters:
[BTW - from what I can tell, we're going with several DC-DC step up and down transformers for each device in the home, rather than one inverter... is that the plan? or are we sticking with one massive busbar running at 12V through the ceiling void?]

Massive busbar... Do things properly damnit!

 

[Swa]

[BTW - from what I can tell, we're going with several DC-DC step up and down transformers for each device in the home, rather than one inverter... is that the plan? or are we sticking with one massive busbar running at 12V through the ceiling void?]

I would like to see this one inverter solution people keep hinting at. Would very much like to do away with my PC power supply and the various other transformers in the home.

 

[Seriously]

I would like to see this one inverter solution people keep hinting at. Would very much like to do away with my PC power supply and the various other transformers in the home.

WHAT? Explain this jewel of a comment so we all can understand!

 

[Seriously]

Every now and then I come back to this thread for a little bit of troll watching. It's fun This is my trool-zoo...

Here's my little food packet for the hungry monsters:
[BTW - from what I can tell, we're going with several DC-DC step up and down transformers for each device in the home, rather than one inverter... is that the plan? or are we sticking with one massive busbar running at 12V through the ceiling void?]

Well if you have 12VDC incoming for all your devices and use 12VDC inverters or DC-DC power convertors at the various plug point in the dwelling the problem remains that a heavy busbar or cables of sorts will have to be used as main supply feed unless you forgo of all the modern conveniances we became accustomed to. There is just no way arround it unless Swa does the design and installation using your standard wiring. At least you will be able finance the solar panels and batteries with the proceeds of selling all your "heavy current" appliances and all other consumer conveniences while you wait for the manufacturers to design low current 12VDC fridges, kettles and hairdryers and wait for government legislation to change the certification requirements. (I wonder who is going to lobby parliament).

 

[richjdavies]

WHAT? Explain this jewel of a comment so we all can understand!

I think I get it now.
- Swa is saying we have loads of rectifiers in all our electronic devices (and power supplies) converting 240V AC to 3-12VDC (these aren't inverters by the way, they are rectifiers... and rectifiers are much more efficient that inverters)
- We're all forgetting that these things are inefficient
- Wouldn't it be great if it was all DC instead

I think what's missing is:
- if the ring main in your house was at 12V, it would need to be super thick or wouldn't power 12V devices - v-drop too high to work
- all my electronics run at different DC voltages, so still need step-up/down transformers
- electronics don't use much of your power in your house...

What we all keep saying is everyone else is on 220-240VAC... so those rectifiers are cheap and plentiful. So the rest doesn't matter.

Oh man, I've been suckered in again... sorry... ignore above

 

[Sonic2k]

I have been told I am wrong.... Amazing since I design stuff that pays the bils.
Anyways
An inverter has always been known to me as a device that steps up a DC supply to an AC one at 50Hz

What people don't effing understand is that it is efficient to chop a high DC voltage into a lower one, NOT the other way around.
When I studied engineering I excelled at design of switched mode power supplies and regulator topologies.