Solar breakdown sticky, stickier, stickiest?

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Minivanmotoman

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There are many on here with a vast knowledge on solar. Great. There are millions more with none, including me. Lol. It is today's hot topic. So let's Save the planet.
Yes I know, determine what you wish to power and then the proper amount of solar/ battery is prescribed. 
It would be great for everyone if there were a quick reference table based upon current retail price/ capacity/ typical usage.
Something like, ex.

Stage   Cost.    Watts. Type.        Battery.   Powers

 1.         $200     100.    suitcase.  35 Ah.     Electronic
2.         $400.    200.    1 panel    125 Ah   Electronics
                                                                         & Fridge
....
10.         $5000.   1500.   +5 panels 1200.   A/C heaven

Or something of this effect stating with a certain budget, you can buy this much capacity ( include typical panels, batteries, controller, wiring, fuses, etc) which is what you need to power popular items and in increasing order. Or the inverse, if you want to power x item(s), need x equipment, costing x $s.
 This would show generally what it costs, what is needed and what can be powered with it. 

I think this would be great and would certainly garner the author, at minimum, a Nobel prize for RV excellence. Or much prestige at an Rtr gathering that many are talking about attending. Maybe a beer or steak dinner?.  :D
Make it a sticky, and as they say, Bob's your uncle!
 
I'd just make a spreadsheet and build in the math. Some things run just a few hours a day while others like your fridge might run 24/7. Calculate the daily usage and take in consideration your climate for what ever heating or cooling you may need and how it might change as you move. Multiply that by the number of days you think you might encounter without solar and then double that so you don't let your batteries discharge more than 50%. The spreadsheet will also help you when you add more stuff that needs power so you can determine if you can run it on what you have or if you need more power generation. Feel free to add to this...
 
AC off of solar?  Not practical. You would need a couple K in panels, and many $ in batteries.
 
To clarify, The whole point would be a GENERAL GUIDE for newbies to understand how much it would cost and the main equipment required to power what items. Not exact calculations or spreadsheets. But that is a great idea for another thread. :)

Ex. To power a fridge requires x watts of panel, x Ah of battery, with the required controller and wiring will cost you APPROX. x dollars TOTAL.

GENERAL COSTS WITH TYPICAL EQUIPMENT AND USUAL ITEMS.

EXAMPLE 600 watts of solar, 250 Ah of battery = $1000 runs a fridge, electronic charging, led lights, etc...

Minimum is say $100 for a small flex panel to charge cell phone, $500 gets you panel, battery, controller and can run lights, fan, electronic charging, etc. $5000 will run your a/c, whether or not it is practical isn't the purpose of the exercise. If you have the money...
 
I don't have cost info, but there is a collection of what can be done with what equipment

Price is highly volatile so it might not be very useful.  But for purposes of comparison: 
  • I am cheap and scrounged and searched and built the basics of my 570w system (panels, controller, wiring, gland, FLA batteries, fuse block) for about $1.50/watt.
  • I added some odd/custom stuff (aluminum channel rack, separate opportunity circuit) that brought it up to $1.75/watt but most folks wouldn't be doing that.
  • Adding shore and alternator charging brought it up to about $2/watt.
I'd imagine that folks buying kits or components new at full price would end up spending $3-4/watt. [Having it installed by someone else might raise the total to $5/watt.]
 
the problem is the electric usage is highly variable. everyone's usage is different and you really can't generalize and say like a fan uses (X)AH. it all depends on the fan and how much it's used. same with everything else, a refrigerator, a lap top, a TV, some can use barely any power and some can suck it up like a dehydrated camel. figuring out power usage is a personnel type thing and yes math is involved. however it's not rocket science and it's not hard.

1. figure out your usage. use the product label or better use a kill-a-watt or DC amp meter. add it all up.
2. size your battery bank to usage. remember with lead/acid it's 50%of battery ah capacity.
3. size your solar panels to your battery bank. 1 watt to 1 AH of battery is a minimum starting point.

now if you can't fit enough solar on your roof you need to reassess and start over. one important thing to remember is, that it is always easier and cheaper to conserve electricity then it is to make electricity. highdesertranger
 
Does anyone comprehend it's not a solar calculator or solar diatribe? Just a general guideline.
Jim, any help here buddy.
Or is this too simple? And will attract too much criticism and overcomplication. If so, omg, my bad.
 
frater secessus said:
I don't have cost info, but there is a collection of  what can be done with what equipment

That is great! Thx J.
 X watts of power allows you to do X. 
Add approx cost info, throw it into an easy to read table and voilà! There you have it.
Many would find that useful to start the solar process
and be realistic in what they can expect and afford.

I see our friend Lenny is on there. Boy does he get around. Lol.
 
Something like Bob's handy-dandy chart?

attachment.php


Cost is a huge variable though. Large 24v panels can be had for far less (per watt) than the smaller 12v panels, and you never know what deals you may run in to locally.
 
The best way to do solar is place as many panels as you have room for and adjust your usage accordingly.I don't understand why people with room for 4 or 5 panels will rack their brains trying to get by with 2 panels.With the new energy efficient appliances,AC and a refrigerator are entirely doable with solar.
 
We have the list right here on the site in the form of successful users. Everything from sub 100w to a handful of up that have giant systems (for a RV) Get each of us to list what our systems are and what they do for us and you have something people can compare their needs to. Charts, forms, calculations with formulas and terms not understood leave people dazed and confused.

Other than that the biggest thing we should avoid is attacking each other because our experiences are different. What would be better is accepting that there are different approaches and results. You may have never ran a A/C on solar so it might be better if you allow someone that does explain what it takes. Once they explain how much panel, how many batteries, the cost, etc, the person asking can decide if it practical.
 
We have the list right here on the site in the form of successful users. Everything from sub 100w to a handful of up that have giant systems (for a RV) Get each of us to list what our systems are and what they do for us and you have something people can compare their needs to. Charts, forms, calculations with formulas and terms not understood leave people dazed and confused.

Other than that the biggest thing we should avoid is attacking each other because our experiences are different. What would be better is accepting that there are different approaches and results. You may have never ran a A/C on solar so it might be better if you allow someone that does explain what it takes. Once they explain how much panel, how many batteries, the cost, etc, the person asking can decide if it practical.
 
mayble said:
Something like Bob's handy-dandy chart?

attachment.php


Cost is a huge variable though.  Large 24v panels can be had for far less (per watt) than the smaller 12v panels, and you never know what deals you may run in to locally.
This is another great table that is halfway there. Great thx! Of course with solar there are many variables.

Take the common, avg standards and take it from there. Averages, STD settings, and state them in the guide footnotes. 

Would be glad to do it if someone would plug me some numbers or work with me. And if you like this idea, please thank or say so to see if there really is any benefit for everyone. No interest? End of story, no prob. Thx.
 
I guess I am not understanding what you want to do. I was just trying to point out that to set up a working solar is a case by case basis. what works for one person might not work for another. there are to many variables. my 12v TV uses 4.5amps that doesn't mean all TV's use 4.5amps this applies to everything, fans, light, refrigeration, etc. you even said it yourself, "Of course with solar there are many variables". I presented the step by step process that should be used, it's not hard, there are only three steps. so like I said I guess I don't understand. highdesertranger
 
OK Jim,I'll start.Camper:300 watts.2 Wally World 125 ah batteries.Propane water heater,refrigerator,furnace.Plenty of power for the tv,lights,furnace fan,etc. Home:3200 watts.14 215 ah 6volt GC batteries.Runs AC,refrigerator,tvs,ceiling fans,clothes washer,dish washer,water pump.Water heater is propane.Heat is wood and propane.Without running the AC,I'm good for 48 hours of clouds and darkness before having to crank the genny.You can never have too much power.
 
Problem is, you need a fair bit of knowledge just to understand that it's just not "that simple".

Working out the actual detailed calculations with the specific equipment you want to power is actually easier than trying to work with general guidelines.
 
no tv until you get 400w? lol my 19" LED uses like 2A at worst.



In my opinion there shouldn't be shortcuts because having solar requires the knowledge and understanding that comes from all the researching you do to get a system. Those who just "want it installed" are always disappointed or needing help....its a leftover of the stick and brick laziness of not having to think about anything.
 
You are right,John.There are always cloudy days,using more power running power tools,etc.I figure the price of panels are so cheap now($94 each for the last 8 I bought)I'll buy enough so I don't have to sweat variable circumstances.I wouldn't know a float from a bulk,but when I check my batteries they are always right up there on the SG.I check every month for fluid level and every 3 months with a resistance tester.I probably could get by with less panels and fewer batteries,but I wouldn't like the stress.
 
John61CT said:
Problem is,  you need a fair bit of knowledge just to understand that it's just not "that simple".

Working out the actual detailed calculations with the specific equipment you want to power is actually easier than trying to work with general guidelines.

I'm of the opinion that in this arena general guidelines might be more of a hindrance than an aide because the specifics and variables are just too great.  A general guideline saying you need 400 watts of power because you run this and that might end up costing you far more money than you actually need to spend if you base your spending on it.  Things based on an average tend to do this.  Buy what you are going to use, determine the power each thing needs, determine how much you are going to use that thing and then size your power generating equipment based on real time data and not averages.  If you don't know how to do this then find someone that does and get it right the first time, or at least as close to right as you can get.
 
Or from the other end, just buy and mount as many watts of panels that you can fit on your roof.

And a pair of the cheapest true deep cycling batts out there, flooded 6V Duracell GCs from Sam's Club or Batteries+

If your input covers your outgo, get back to 100% Full every day, you have enough panels.

If the batt gets below 50% when it's cloudy for a day or two, buy another pair, ideally within a few weeks of buying the first pair.

Or if you don't have enough solar, another batt won't help, you need to cut consumption or buy a little genny. Unless you can plug into mains power every other day, that will solve all your troubles.

Get a hydrometer, DMM and some sort of ammeter to verify you're not murdering your bank.

Simple as you can get, at least enough to get you started.
 

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