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up-voted for best non sequitur on the thread 
«While I complain of being able to see only a shadow of the past, I may be insensitive to reality as it is now, since I'm not at a stage of development where I'm capable of seeing it.» Claude Levi-Strauss (Tristes Tropiques, 1955)
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It seems he deleted the account, or was he kicked? I enjoyed his pearls of wisdom!
GCS d-- s-/++ a- C++++ U+++ P- L+@ E-- W++ N+ o+ K- w+++ O? M-- V? PS+ PE- Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- ++>+++ y+++* Weapons extension: ma- k++ F+2 X
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Not sure, but for me it Looks like he is now CodeWraith ?
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I don't know, but maybe somebody mentioned the war? 
Anything that is unrelated to elephants is irrelephant
Anonymous
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The problem with quotes on the internet is that you can never tell if they're genuine
Winston Churchill, 1944
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I'd just like a chance to prove that money can't make me happy.
Me, all the time
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Nah.He is so small and shy that he was probably scared away by bullies.
I have lived with several Zen masters - all of them were cats.
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I was looking at some Solar Energy stuff.
The question in my mind: Can these systems truly power the common residence today ?
I'm thinking, it's easily conceivable that the normal home today can be running these appliances all at once; particularly in the late afternoon and evening...
- Washer
- Dryer
- Stove
- Oven
- Microwave
- Water Heater
- HVAC (in all its variations)
- Computers
- TVs
- Vacuum Cleaner(s)
- Refrigerators and Freezers
...and I'm sure my list is incomplete.
I'm wondering (and asking those who have electrically minded brains which are superior to my own) is the extant 120 Volt grid a factor in all this ?
I just bought a bunch of LED replacement lightbulbs last month. My guess is that, bang for the buck, the point of max economy today is about 80 or 90 Lumens Per Watt.
(I welcome correction on that figure; it's based on my observation of a local grocery store's shelves.)
Now then, if we can get 85 Lumens per watt from these new fangled bulbs, and if we can get a solar system that delivers lower voltage (e.g. 12 volts; whatever) yet higher current (big "ifs",,, I know) then do I have a workable science turned business model ?
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There are quite a few videos on YouTube to watch to get you started.
A LiIon battery pack is the best way to go. Also its better to use series connections for batteries and solar panels and go for a 36v, 48v or even higher DC system to keep the current lower, its more efficient that way.
MPPT charge controllers are very efficient at higher voltages, and depending on how much you spend you can get a lot watts out of the system.
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With 12VDC instead of 120VAC with a constant P(consumer) (which is almost realistic with modern switching PSUs) the required current rises by a factor of 10. Which means the voltage drop across the power line rises by a factor of 10. Which means the power loss across the power line rises by a factor of 100 (P = U*I -> P = R*I*I -> P = R*I²).
This is a bit simplified but good enough for illustration. Low voltage supply lines only make sense for either really small currents or really small distances. House supply is already too big, in both current and distance. In order to not turn the power line into the house heating unit you would have to increase its diameter considerably which is both expensive (copper) and unpractical in terms of installation.
If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson
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Following that logic would 240VAC be better than 120VAC, Oz runs on 240 and I have always wondered why, other than we probably followed the UK standards.
I obviously know practically nothing about electricity, we installed solar and I only then found out the house we bought has 3 phase power and therefore I needed to know what the hell it is. Now I'm looking for and efficient 3 phase battery solution.
Never underestimate the power of human stupidity
RAH
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Mycroft Holmes wrote: Following that logic would 240VAC be better than 120VAC
It is, at least in this regard. That's also why the the power grid operates on an even higher voltage and only gets transformed down shortly before reaching the consumer.
Mycroft Holmes wrote: Now I'm looking for and efficient 3 phase battery solution.
No experience with that, sorry.
If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson
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The 120 V makes sense if you can get 120 V appliances easily - like the OP in the US.
As for your 3 phase, it prolly means that a few of your machines run on it. Most machines (e.g. microwaves) and all lamps and household sockets are only connected to 2. Maybe an option in your case could be to leave the 3-phase-machines on the grid, and build 2 phase solar system for others. I never heard of a 3-phase-DC/AC-converter but 2-phase-ones are easily found.
... such stuff as dreams are made on
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You can get a reasonable lumpy DC supply from three phase with a suitable capacitor and that gives you the ability to run arc welders, lighting stantions (out door concert lights) all sort of big boy toys that you probably not want or need in your life, however a lumpy dc with near 100 amps means you could charge Tesla's with ease. Nice to have but you will pay over the odds to get kit that uses it safely keep with the safer more manageable 240v instead of 415v, you could use one phase for charging the battery pack, the other two for running the house. 
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Charging your home and your Tesla on solar? Only if your roof is big enough. 
... such stuff as dreams are made on
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I have seen some Aircraft Hangers suitable, however the heating bill in the UK would be a down side...
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In direct sunlight and no obstacles, the inflowing solar radiation may go up to roughly 900 Watt per square meter. That is at mid-day, sunlight taking the shortest way through the atmosphere; in the morning or late afternoon the radiation slopes through maybe 2-4 times as much air, and is significantly weakened. Photoelectric solar panels usually are 18-21% efficient, so don't expect more than 175 Watt/m2 even at midday. So it takes 6 m2 of panels to collect 1 kW (if you like: 1 kWh per hour )
That is if the panel points directly to the sun. It doesn't. If the angle between the panel's orientation and the sun is v, the energy collected is cos(v). If your panel is laying flat on your roof, and the sun is 60 degrees over the horizon, the theoretical influx is 150 W/m2. When the sun sinks to 30 degrees, influx drops to 85 W - but that is for the geometrical aspect only; the atmospheric loss comes in addition.
When the angle increses, there is a third loss: At a microscopic level, the active element is not at the very surface, but lies in a "dip" or "valley", with "mountain sides" that may fully or partially shade it, reducing yield even furhter than cos(v) indicates.
Yet another loss, caused by the way the cells are hooked up in a panel, in long chains: If a shadow falls on parts of a chain, e.g. from a tree branch, or a dry leaf landing on the panel: Even if only a few percent of the cells in the chain are shadowed, this will to a large degree choke the entire chain.
Then you have the large "shadows": The clouds. How many hours of sun do you have during a year? That varies a lot from country to country, and from coast to inland, from lowlands to highlands. Photoelectric cells definitely do best in sunlight; they do have a yield even in cloudy weather with diffused light, but far less.
So, the bottom line: In Sahara, California etc. where you have no need for heating, and you can have your batteries recharged every single day by at least eight hours of bright sunshine, you might cover your entire roof with solar panels, and you can probably go completely off-grid. Here up by the polar circle, you would have to cover your entire garden with panels, and fill up your basement with Li-Ion batteries to get through the winter. (That is after you have found that gold mine for paying the investment...).
Solar is fine for low-effect uses, like light, alarm systems, communication, as well as for emegeny use. If you want to go completely off-grid, think of alternate solutions, like thermal heat collectors for heating (at least 4 times as efficient as photocells), cooking on gas etc.
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USA did not follow UK standards! UK standard is 240volt for standard domestic supply and 440volt of 3 phase.
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Well 240 is the old now you can get anywhere from 227 to 250 out your wall socket thanks to the fact the EU use 230 (with no earth!) and the 'easyest' way was to relax the standards. Not really an issues as most devices like washing machines will take 220-250 to make life easier for the manufacturer and most things that don't use motors have a switch mode power supply...(just to make life awkward for RF engineers...)
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glennPattonWork wrote: 230 (with no earth!) and the 'easyest' way was to relax the standards.
No Nanny State Safety Standards for you guys in the EU !
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Quote: No Nanny State Safety Standards for you guys in the EU !
My dear chap, former EU (!?  )
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Mycroft specifically mentioned Australia, not Merka. Reread his post.
Michael Martin
Australia
"I controlled my laughter and simple said "No,I am very busy,so I can't write any code for you". The moment they heard this all the smiling face turned into a sad looking face and one of them farted. So I had to leave the place as soon as possible."
- Mr.Prakash One Fine Saturday. 24/04/2004
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Wkipedia knows it: Three-phase - Wikipedia[^]
Here in Germany power is always supplied as 3-phase for building connections. But private households usually do not have equipment that requires it. The only common devices that have 3-phase connections are cookers. But they just split it into three 240 V lines internally (e.g. one for the stove and the others for two plates each) and can be usually also connected to one or more 240 V lines.
Similar is done in the distribution boxes: Splitting into three 240 V lines for supporting the different connections.
There is also no "3-phase battery solution". There are DC batteries loaded by the panels and a switch supply generating the required AC. You might ask an electrician if it is really necessary to use a 3-phase switch or if the output of a 240 V switch can be attached to some or one of the 240 V lines from the distribution box (assuming that the solar power is not able to power the whole house).
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We pump the same amount into the grid during the day as we use after the sun stops, paying 50c kwh getting 6c kwh. If I could use that 50% I could almost eliminate the power bill.
Never underestimate the power of human stupidity
RAH
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You could buy a threephase UPS and modify it.
But they're f***ing expensive.
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Sounds good. Then you already have a switch supply and just need some batteries inbetween (and calculate the time until it gets a good return).
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I think that it is standard in most European countries with the exception of UK.
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