Well then, you should be able to show your energy audit listing all item run, the watts they use and how long they are run as well as the total daily Whs total.
Then the calculations for the system sizing.
The interesting part will be to see if Ron can do this. After all, he claims to have designed his system so it would not br unfair to assume that he knows this information.
But I am sure that he will have several excuses for not doing so.
1) His system design is so advanced that no one here could possibly understand it.
There he goes again. Couldn't leave well enough alone.
The only person that George makes seem silly is George. When he sets up his little "challenges" and claims he knows the response, he is starting to cover up his own ignorance. Another of his ploys is to accuse "others" of lying about numbers. If sufficiently challenged, his insecurities and ignorance will lead him into name-calling which will become progressively obscure as he delves into local and made-up sources for his comments.
George, you seem to have an overwhelming need to denigrate others in order to try to prove something about yourself. This is common in immature and insecure people and even cultures, so I guess that explains this phenomenon.
I wouldn't bother to recreate the data in any detail, because you have demonstrated many times that you are unable to understand real data, or even comprehend the nature, value or trade-offs of sophisticated simulations. You've never posted anything to indicate that you can even perform simple sensitiviy analyses (or even know what they are).
All you can do is plug stuff into a simple spreadsheet, and most of the time you don't even get that correct, without a great deal of prompting (and sometimes not even then).
Your "tool" -- your spreadsheet, doesn't even include the cost of grid extension, propane (or other fossil fuel), cost of grid-supplied electricity, proper computations for battery capacity at different battery loads, and all the other items that are important not only in designing a system, but also in determining whether the system even makes economic sense to install at all. It has zero ability to determine, for example, whether the system is better if it has, for example, more batteries and fewer panels, or vice versa. Or the effect of adding in a wind-turbine. Or the effect of adding in a micro-hydro turbine. Or what the effect of $4/gal propane will be if you are using a propane generator for supplemental battery charging.
My system was designed to supply a certain amount of energy per day -- I don't have the sheets handy, but, as I recall, it was about 16-17kWh/day in the summer, and about 21 kWh/day in the winter. It was also designed to supply the maximum power that the house might draw, with no requirement for a backup generator to do anything other than charge batteries when the renewable resources were insufficient.
Because it was also designed to do that as economically as possible, a system that did not rely 100% on renewable sources was considered.
That involved not only simple-minded stuff like some of the calculations you try to do with your spreadsheet, but also data on costs of wind turbines, PV installations, propane generator, batteries, cost of propane, actual solar resource, actual wind resource, cost of money, inflation rates, capacity of the battery chargers, battery setpoint SOC (to what level should the battery charges take the battery, if the generator had to be used) and numerous other items.
My system performed within 5% of the simulation predictions.
Initially, the simulation demonstrated that I would obtain about 80% of my energy from wind, and 20% from a backup propane generator (used only to charge batteries, not to power any unaccounted-for loads).
It didn't do quite as well, with the split being 75% wind, 25% generator. The reason was easy to see as the wind resource was slightly less than the preceding 10 year average winds for the area (from a local sensor).
But my simulation also gave me a price point on propane where adding solar panels made more economic sense than running the generator. I did that at the appropriate time, and the system is continuing to perform as predicted by the simulation, even to the gallons of propane required to run the generator. And it tells me how much higher the cost of propane would have to go to make it worthwhile to add even more panels.
On the other hand, your confusion, demonstrated by your postings, about power, energy, volts, amps, watts, time and so forth is legendary, and well documented at
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Your attempt to make false claims is transparent. Why, only in this thread you have posted:
when there is absolutely zero evidence that you ever had any real accreditation from any worthwhile accrediting board. When I asked why you weren't listed, you wrote that, well, you are not accredited now.
In a discussion of energy consumption, you write:
as if this makes a difference in energy use.
In other posts you write about
panels for a 12V nominal system having a 17V output under open circuit conditions, again showcasing your ignorance;
you claim minimum battery requirements for a particular system as being
180Ah at the 100 hr rate when it should have been at the 30 minute rate, and you do this repeatedly even when challenged.
you claim you have better numbers than those published by the mfg in determining battery capacity, so the battery should have 50% more capacity than that determined by the mfg.
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You even claimed that 1.15 hrs was only 0.09 minutes more than 1 hr, demonstrating your limited math skills at: snipped-for-privacy@h17g2000prg.googlegroups.com
GG: Do you really think that .09 of a minute is going to make that much of a difference.
Nick Pine (1999): "Who would hire this PV nitwit" Wayne (2008): "... a true Renaissance nitwit"
You know what I was getting at. Let's not put too fine of point on it. It is electrically more sound to make the proper voltage battery first, THEN parallel them, if absolutely necessary, to increase capacity.
Larger oil patch diesels often have hydraulic starters. Huge electric ones are too hard on the ring gear and assorted fittings. A hydraulic motor can be eased on slowly to full power.
There is a smaller auxiliary engine that first starts up to provide the hydraulic pressure. That engine usually drives the alternator also. In nicer set ups, the coolant for the large engine is also warmed up a bit before start up. They have to, as in cold weather, the lubricating oil is like molasses and 12 or 16 pistons don't like moving in it.
Someone once said that there's nothing new under the sun. My only experience with a Deere tractor was hand starting a two cylinder gasoline version. You had to open the compression releases by hand, spin the flywheel and when the thing was chuffing, close the valves. It was really brutal on cold mornings.
Due to the insane amount of spam and garbage, I block all postings with a Gmail, Google Mail, Google Groups or HOTMAIL address. I also filter everything from a .cn server.
That depends on how you look at it. What is electrically sound??? The point could be made, very convincingly, that a series/parallel connection should be exactly that. A GRID connection, placing 2 sets of cells in parallel, AND 2 strings in series, with each pair of cells connected together, and each string of cells connected together. Strings + to - and pairs + to + and - to -.
And many trucks and tractors also use 2 huge 6 volt batteries in SERIES for starting batteries. Then there's the old standard - 24 volt starter and 12 volt lighting and charging with the solenoid series/parallel switch. To start the truck the battery string goes to series for 24 volt starting which only requires roughly half the current - then the system shifts back to shunt for charging - and the batteries share charge and load. (Delco system on GM, White, Kenworth, Mack, and Chevy HD trucks and Waukesha Industrial applications, as well as some Cat equipment)
I think there is more than one reason why that system passed from the scene about 20 or 30 years ago. (reliability of the series/parallel switcher being a large part of it)
Anyone doubting they exist look up Napa SPS844 and SPS845 as well as the SPS866 and SPS867
In alt.engineering.electrical snipped-for-privacy@gmail.com wrote: | On Aug 9, 6:09 am, snipped-for-privacy@ipal.net wrote: |> In alt.engineering.electrical Ron Rosenfeld wrote: |> | On 8 Aug 2008 18:32:00 GMT, snipped-for-privacy@ipal.net wrote: |> | |> |>If the effect is that the _older_ strings gets _older_ faster, |> | |> | And if it is the newer string that gets older faster? ... Well, maybe you |> | won't get the longevity you thought you'd paid for. |>
|> Right. So we need to know which it is ... which string gets older faster. |>
|> | In any event, the "best" setup does depend to some extent on the |> | application and goals. |>
|> How about a power backup system (charged by the grid) that gradually shifts |> to a renewable power system (charged by solar, wind, etc) and then eventually |> to a completely off-grid system (or at least a sell-only grid system). |>
|> -- |> |WARNING: Due to extreme spam, googlegroups.com is blocked. Due to ignorance | |> | by the abuse department, bellsouth.net is blocked. If you post to | |> | Usenet from these places, find another Usenet provider ASAP. | |> | Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) | | | Phil | | People have explained several reasons for "NOT" paralleling batteries. | It should be avoided wherever possible.
If you'd like, feel free to summarize the thread. I plan to look it all over again once it seems all the responses are done.
| You response tells us that you have/want parallel batteries and you | are looking for someone to tell you it's ok.
No. If there is an alternative, I'm willing to consider that. So what would you suggest as an alternative? More in series and increasing the voltage?
| So, Yes it is ok. As long as you also accept that it is the second | best option and are prepared to take all responsibility for your | choice of battery bank.
In alt.engineering.electrical Ron Rosenfeld wrote: | On 8 Aug 2008 20:09:04 GMT, snipped-for-privacy@ipal.net wrote: | |>In alt.engineering.electrical Ron Rosenfeld wrote: |>| On 8 Aug 2008 18:32:00 GMT, snipped-for-privacy@ipal.net wrote: |>| |>|>If the effect is that the _older_ strings gets _older_ faster, |>| |>| And if it is the newer string that gets older faster? ... Well, maybe you |>| won't get the longevity you thought you'd paid for. |>
|>Right. So we need to know which it is ... which string gets older faster. | | Read that paper again and work out the physics. Assume two strings of the | same make/model/size but one is older. Note that the older string will | have a lower capacity. Think about the relative resistances. Which string | will supply most of the initial load? That will be the string that cycles | most for shallow discharges, and will most likely age the fastest.
As long as there are no other "hidden" issues, that makes sense. I just don't want to jump to such a conclusion before ensuring that all the issues are known. I am not trusting any one single paper/article to cover all the issues.
|>| In any event, the "best" setup does depend to some extent on the |>| application and goals. |>
|>How about a power backup system (charged by the grid) that gradually shifts |>to a renewable power system (charged by solar, wind, etc) and then eventually |>to a completely off-grid system (or at least a sell-only grid system). | | I would only use parallel strings if I had no other choice. In my case, I | have two parallel strings, but that's because I could not obtain batteries | of the size and capacity I wanted to set up a single string. When these | need to be replaced, it will be with a single string of 2V cells (which are | now available in a suitable capacity for me). Maintenance is much easier | with fewer cells to care for.
Are you going for the 33 plate Surrette 2KS33PS cells?
In alt.engineering.electrical m II wrote: | snipped-for-privacy@ipal.net wrote: | |> | I have never seen single cells paralleled. They are always connected in |> | series to get the desired voltage. Then, another group of identical |> | series cells may be paralleled with it. |> |> So the "reason" is "everyone else does it". | | Not at all. If you want 48 volts and have two volt cells to play with, | that is 48 jumpers for the paralleling the 48 cells. Add another 24 for | the series portion. That is a total of 72 jumpers. It's easier to make | two batteries first, then parallel them with two jumpers.
I was planning on looking at this, and other, costs later on. I wanted to know the technical, not economic, issues. Then I would balance between them. If method X costs more, but works better, I might still consider it over method Y that costs less, but doesn't work as well.
I'm focusing on the technical issues right now.
|> Aren't all the plates within one cell already parallel? By extension of that, |> paralleling individual cells would make sense because it retains the very same |> concept. | | No. They are each in series with the one next to it. The power comes in | on one terminal, through the electrolyte and out the other plate. There | is no chance of any circulating currents within one cell. They all share | the same electrolyte bath. If there were only two large plates in a | battery, we wouldn't call them paralleled. Take those two plates and | roll them up in a cylinder shape. It may look a lot different, but | they're still not paralleled.
How is it that the common electrolyte bath prevent circulating currents? Does it have circulating currents in the bath itself when plate surfaces are uneven?
Yes, I would still call a 2 plate (one "+", one "-") as parallel ... it is paralleling multiple spots of each plate with other spots.
More plate surface means more current and/or capacity. The distinction is whether the plates are in the same common bath, or separate. The problems that can happen because the bath is separate, I want to know about. But it needs to make sense in terms of the bath, so I'm looking also for theory, not experience alone (even if the theory is just theoretical).
| Now, there *are* multiple plates on each polarity because of space | constraints. There's no room for two huge plates with the same surface | are. Changing the shape of each polarity plate won't make it parallel.
Well, you could have a long battery :-)
I understand how they are physically constructed. There are lots of plates in an interleaved configuration so that instead of it being a big long thin cell, it's a convenient semi-cubic shape (and you can have most plates do double duty front and back facing).
If any part of a plate is in a weaker charge state, the other parts of the plate that are in a stonger charge state effective charge it, and it all gets balanced out. If two cells are paralleled, that should happen between the cells, as well. Now I could imagine that if the electrolyte condition is what causes the cells to be slightly different, that can impact how well the cells balance out their charge. Presumably within a single cell the electrolyte can circulate around (not considering AGM or gel-cell here) so each point on the plates gets an equivalent electrolyte.
| snipped-for-privacy@gmail.com wrote: | |> Uh no. the best two volt cells have "L" shaped posts that bolt |> together and are then soldered. | | You know what I was getting at. Let's not put too fine of point on it. | It is electrically more sound to make the proper voltage battery first, | THEN parallel them, if absolutely necessary, to increase capacity.
If you are building a system from scratch, and selecting the cells/batteries, would it be your intent to find invidual cells/batteries of the intended AH capacity so you can have a single string (nothing paralleled)? If so, then what percentage of economic savings would half capacity cells/batteries need to be priced at to make you choose to split it into 2 parallel strings? Or the same for quarter capacity for 4 parallel strings? Would a 15% savings (in dollars per AH) be enough to make it worth splitting?
But there is more to battery selection than just capacity vs. money, sometimes design issues get in the way.
As I stated earlier, my battery bank consists of two strings of two 6-volt batteries, but the two strings are not even in the same building! Electrically, they are all the same battery bank, but I keep one string near my generator to assure plenty of starting current, and the other string inside my house to potentially run inverter loads following a power failure. (I have never done it) Heavy paralled conductors connect the two strings, which make them effectively one battery bank, except for that tiny bit of time when there is a heavy load on one side or the other. (Ohm's law, if there is hardly any current, there is hardly any voltage drop) Also, that configuration gives me the option of splitting the strings to assure that I always have sufficient capacity to start my generator.
I haven't yet measured accurately, but it appears as if they will fit into the same footprint as my 8CS25P's. That being the case, they would be at the top of my list today. They have a bit more capacity, and I'd have half the cells to care for. Of course, when the time comes, I'll see what's available.
Ever wonder why the cells in a car battery are separated? If it didn't matter, they wouldn't do it. The electrolyte is conductive, but it's rectification qualities are nil.
No. The protruding pieces of plate probably get eroded faster as the cell is used.
Don't confuse the plates, which are in series, to the current flow in the electrolyte, which may have millions or billions (biwwions, for you Carl Sagan fans) of parallel paths between the plates.
The electrolyte provides parallel paths. How the area of one plate is arranged is immaterial, outside of structural constraints.
I don't know if that is important or not. Off hand, I would think that there is very little difference between sandwiched plates and two large ones of the same total area. I can't say for sure. I don't know.
I think not. At that point it's a chemical state. I can't see that 'migrating' across the surface. The most chemically active portions would be the ones to see most of the current flow to the other plate, however, until physical erosion teaches them a lesson.
Sure. Electrolytes can get gassed off at different rates. The distance between the plates, surface condition of plates and the sediment at the bottom of each cell also count. Not all cells are created equal. The weak ones put more of a load on the good ones. The gassing rate changes because of unequal current flow in a parallel setup. The specific gravity varies with charge and how much water has been forced out or mutated into hydrogen. Unequal current flow is where all the problems start.
These guys can explain it in a better fashion than I've been able to do:
Due to the insane amount of spam and garbage, I block all postings with a Gmail, Google Mail, Google Groups or HOTMAIL address. I also filter everything from a .cn server.
Geez, Ron, give it a rest, willya? Everyone knows that *eorge is a dick and most of us have him killfiled. He's talking to himself and you. Killfile him and get on with life.
John
-- John De Armond See my website for my current email address
That is basically how the diesel aux generator in my nuclear submarine started, compressed air straight into the cylinder. After a 60 day submerged cruise we would place bets on how many tries it would take to get the thing to start. It was seldom pretty.
Here is another way to look at it. Series strings have enough problems of their own. No two series strings can be 100 percent identical. When we parallel two or more strings, the chance for problems is multiplied.
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