Renewable Energy Systems (Solar)

Hi all. I just found out that this new sub forum was made recently and I am happy to see it and I thought I'd make a thread on renewable energy that people have been asking to get.

I will go into some basic details for renewable energy and some of the stuff that you need for a off the grid system and these can be changed into grid tie in systems with the hardware.


----- Solar -----
- Solar Panel(s) or stuff to build your own (building your own you have to know how to do it right)
- Inverter(s)
- Charge controller(s)
- DC Beaker Panel
- DC Rail(s)
- AGM battery bank.
- Right gauge of wire



- Solar Panel or build it your self kits -
You will need solar panels that will charge your battery bank. Depending if your doing a 6v, 12v 24v and even 48v systems all the stuff ie panels, charge controller , battery bank all must be the same voltage. Depending on your amps and watt needs you will have to fine tune if you produce more amps or more watts.

If you chose to go the route of building your own you will need to find the right kind of cells that you can use. Some people go for the bigger cells and some go for a smaller cells ie 6"x6" or even 2"x2" cells. From my research I found that 2"x2" cells are the best because they are smaller and you can wire them in series or parallel and I will get to this in a bit. Along with the cells you need a 20w or 25w soldering iron because to much heat will damage the cells, bus wire, tabbing wire, at least a 60 alloy/40 tin solder mix. You will also need around 1/4 inch thick glass that can stand up to high winds, rust resistance metal frame. If you want your home made panels to last a long time you should invest into a PV Solar cells EVA Encapsulant, Junction potting Solar Cell Encapsulation kit. They aren't super cheap but this will make your panels have a longer live over the cheap way of making them because the PV Solar cells EVA Encapsulant, Junction potting Solar Cell Encapsulation seals the cells and such thus preventing water getting to them. Last but not least you will need to buy and use blocking diodes for your panels and this will prevent the power in your battery bank leaking back to your panels.


- AGM battery bank. -
Now its the battery bank time. The reason why I said AGM (Absorbed Glass Matt) is because they have a longer life span and I've read that they can be ran indoors because it doesn't off gas like other kinds of batteries. Depending on how much you can afford to spare for the battery bank since its costly you can go with a single 6v system and upgrade from there or go for a system that you want to go. Most systems for basic setups are 12v because you can get a 12v battery. I have come across 2 different 12v AGM batteries. 1 has a rating of 1.4kwh at 120 amp hour to a 2.8kwh at 220 to even 240 amp hour. Because you shouldn't drain the batteries below 80% having more batteries in your bank will increase the kwh and amp hour that you can use in your bank. Don't forget you can always add onto your battery bank.


- Charge controller(s) -
Now its time to talk charging. You must get a charge controller because over charging your battery bank is very bad. Depending on the voltage you want your system to be your charge controller has to handle that kind of battery bank. Also when buying a charge controller you need to look at how many watts and amps it can handle because this will determine what amps and watts your solar panels wired up in series and parallel can put out for it to handle.


- Right gauge of wire -
I don't know much about this but all I know is that you need to get the right kind that can handle a higher amp,watts,volts going though it when your panels and such are far from the panels.


- Inverter(s) -
This is where you get your DC power into AC power. Get one or ones that is just high enough for what you need to power with it. Also make sure it can handle the right kind of amps going through it to and your using the "true" running power it produces and not the start up it gives.


- DC Beaker Panel -
Just like a AC breaker box in your house a DC breaker box is important to go to because that will help protect your stuff from power surges. Also going with a DC breaker box and rails is that you don't have to figure out what you need for ac way because you run a wire from the panel to the inverter to give you ac.


- DC Rail(s) -
Almost like your ac rails for your house but the difference is that I was told they use car fuses for them and the rails have a amp rating to and if it gets over loaded or w/e it will blow the fuse that you install into the rail.



So that is the basic run down. Now it will run you around $500 to around $700 for a very basic system if you chose to build your own solar panels and the biggest cost of that is the battery because they can go for $300 to $700 if you go with a 12v 1.4kw/120amph battery or a 2.8kw/240amph battery.

If you chose to build your own to can build a 10w to 16w panel or more then 1 depending the prices for stuff where you live.


I know that the start up cost is alot but where I live I pay $0.09 per kw and for the 1kw we have to pay around $0.10 per kw. Now you may still think that's now worth it but when you set your panels up in the right series and parallel you can produce more watts and amps when you hook them up right and that meens each panel helps give each panel a little boost.

A 10w to 16w panel system producing around 5 hours of top power production you can produce around 1.5kw to around 2.4kw every 30 days and in the summers some people can get up to around 7 hours of top production and if you get that for even 1 month you can produce up to 2.1kw to around 3,360w every 30 days.

So those numbers you could get $0.15 to even around $0.336 every 30 days.

Here's some more number crunching. If you were to buy a 100w panel and it cost around $300 to $400 you could have bought do it your self kits and build a 120w to a 256w panel setup for the same price.

The other advantage with building your own panels you can buy it in parts and some of it you won't have to re-buy for a few panels and add more to your system.




----- Series -----
When you wire devices in series the volts increase but the amps stay the same.

----- Parallel -----
When you wire devices in parallel the Amps per hour produced from the panels is increased and the Amp Hours in the battery bank is increased but the volts say the same.

Very nice. Love the detailed write up. It's timely too. Been looking, because I'm in a rate tier state and it is impossible for this (small) house to stay in Lifeline. Most of mine is above $.09 some is <gulp> $.31 I go over into the highest tier also.

I glanced at a Solar kit in Frys Electronics. Big money for small watts. This makes more sense.

Oh, and wire is pretty simple. Bigger (fatter) wire for higher currents and longer runs.
12 guage is house wiring for 15-20A @ 115v. Goes back to your panel, so that's the standard for current and distance. Wire is bigger or smaller from there, is how I look at it. For example, I'm running a sub-panel to the garage. That will take 8 guage because the breaker will be 50A. The cables in the battery bank are fatter than the wires from
the solar panel. Like that.

Doer said:

Very nice. Love the detailed write up. It's timely too. Been looking, because I'm in a rate tier state and it is impossible for this (small) house to stay in Lifeline. Most of mine is above $.09 some is <gulp> $.31 I highest tier go over into the also.

I glanced at a Solar kit in Frys Electronics. Big money for small watts. This makes more sense.

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Thanks. I've been doing research for good portion of this year. I started back in the winter time and sort of still reading up on some stuff. So at that $0.31 per kw it will help pay back for its self even faster. I was looking at buying a 100w off grid system a a couple months ago and if I was to do that I would be paying around $1,000 to $1,200 for a 100w system and to me that is not worth buying when in that case if you can build your own its easier to get the stuff to . Its even more hard if you can't put it onto cc or have the cash on hand to get the parts for your own solar system in 1 shot or as soon as possible.

Where can you buy the necessary cells? How expensive are they? cn

idk what you know about these http://www.spheralsolar.com/products/100W-Golf-Cart-Solar-Roof-Panel-Kit.html but i think i can convert my fleet alot cheaper and get more miles, what do you guys think? i'm working on greening and getting some gov credits while i am at it.

This year i tinkered with a 30 watt panel that ran my outside hydro DWC 2 buckets & 2 15 watt air pumps.

It worked alright but i had to set a timer for the pumps so the battery would have enough energy to make it through the nights.

cannabineer said:

Where can you buy the necessary cells? How expensive are they? cn

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Depends where you live because prices are different. I can get a 25 pack of 2"x2" for $25 and that will be enough to make a 10w to 16w panel depending how I wire them together

mysunnyboy said:

idk what you know about these http://www.spheralsolar.com/products/100W-Golf-Cart-Solar-Roof-Panel-Kit.html but i think i can convert my fleet alot cheaper and get more miles, what do you guys think? i'm working on greening and getting some gov credits while i am at it.

Click to expand...

If its the panel its self that is over paying you can make a 100w panel your self for less if you make your own. Heck depending how much you use the kart you might not need a 100w panel either.

RyanTheRhino said:

This year i tinkered with a 30 watt panel that ran my outside hydro DWC 2 buckets & 2 15 watt air pumps.

It worked alright but i had to set a timer for the pumps so the battery would have enough energy to make it through the nights.

Click to expand...

Well depending on the battery you have to but one that I was looking at has roughly a 9 hour run time before the watts in the battery bank is at 80%. Don't forget that Amp hours is very important to in a solar system even more. Also if you can maybe invest into a 2nd battery to run your 2nd pump off of and a separate solar panel for that 2nd battery to run the 2nd pump.

The trick with solar systems you have to brake up your battery bank to run different things on different battery banks for example a fridge/freezer combo should be on their own bank because if it has no power your food can go bad. If you have a 2nd freezer then that should be on its own bank to.

Things like cloths washer and dryer depending if you need your cloths to be washed and dried over night or in a day then they might need their own bank each and if not then they can be on the same bank and you can just wait for the battery bank to get fully charged.

I thought the wattage was strictly a function of cell area, within a batch of cells. Your wattage varies depending on how you wire them together. What am I missing? cn

cannabineer said:

I thought the wattage was strictly a function of cell area, within a batch of cells. Your wattage varies depending on how you wire them together. What am I missing? cn

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Watts is depending on how your panel that you make is wired together.

Here's an example what a 2"x2" cell specs is

Amps per cell - 0.88 - 1.10
Volts per cell .57


The difference between the 2 is that the 2 cells wired in series produce a higher voltage but the amps it produces stays the same. The 2 cells wired in parallel will produce more amps but the voltage will stay the same. Now the part that makes things a little confusing is where you are at. No cells will produce exactly the same amount of volts and amps each. So wiring them in series and or parallel the wattage won't be exactly the same as 2 cells with. You could have a 2"x2" cell produce 0.50 volts at say 0.75 amps and a 2"x2" cell producing 0.57v at 1.10 amps.


I can't do the math for that kind of difference because 1 I don't know how it would go and 2 I don't want to give the wrong numbers on it.


So you could end up with a 2 cell panel that will produce a different amp and voltage thus the wattage will be different. How hot the cells get how much sun strength and many other things come into play on how much a panel will produce.

Oh ... OK, I think I see that ... thanks. cn

cannabineer said:

Oh ... OK, I think I see that ... thanks. cn

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Your welcome. Don't forget that if your system uses x amount of amps and watts per hour that your solar system can produce that or a bit more per hour.

Also because the amp hours a battery bank can hold isn't as high as wattage you have to make sure your system can produce enough amps to cover the usage to.

So taking your best numbers ($364 to build, $0.636 saved per month) your net amortization period is almost 48 years. With the $700. battery it's just over 100 years. Those numbers assume unicorn-type stuff, like efficiency of both source and storage remaining as-new over the entire span. I'd need vastly better ratios to be interested ... cn

cannabineer said:

So taking your best numbers ($364 to build, $0.636 saved per month) your net amortization period is almost 48 years. With the $700. battery it's just over 100 years. Those numbers assume unicorn-type stuff, like efficiency of both source and storage remaining as-new over the entire span. I'd need vastly better ratios to be interested ... cn

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Well the price of things have been drooping but don't forget when you add more panels your watts and amps per hour you produce will go higher.

Also if you want to cut the cost and not buy another $300 battery you could buy one of those portable batteries for around $100 to hold more power.


Always remember

Amps * volts = watts

If you build a panel that puts out 1.10 amps you can take the left over cells and build a panel to sell. A 5w panel around here sells for about $30 to $50 so if you have left over panels make a 10w panel and you can sell it for around $20 or w/e. So if you build a 5w panel from a 25 cell kit you could make 2 to 3 panels and make around $10 to $20 profit. And there are people out there that will buy them.

Also I have been thinking about looking into those battery backup system things because those might be a way to save more power and cost less then buying another $300 battery.

...what about plastic sheet materials with nano-antenna embedded? I reaaaally love this idea. Most specifically for third world 'super-sunny' areas.

Imagine that

I'd love to be able to recycle plastic bottles into shake roofing with this technology integrated. Would potentially 'solve' garbage island, and my electricity bill.

eye exaggerate said:

...what about plastic sheet materials with nano-antenna embedded? I reaaaally love this idea. Most specifically for third world 'super-sunny' areas.

Imagine that

I'd love to be able to recycle plastic bottles into shake roofing with this technology integrated. Would potentially 'solve' garbage island, and my electricity bill.

Click to expand...

Pretty much as lot as you can seal the solar cells so that no air or moister gets to it could do a open layout like have it against your window so that the sun that hits it gets turned into power and such. Build the frame is just for people who want to make sure their cells will last a long time.

I plan on doing a spread sheet and finding out if there are things you can use to measure how much power goes into the battery bank and how much power you use and log it.

Doing solar is also good if you use those path lighting things but you could build your own system that they will last longer with and even because its Christmas you could use solar to help power some of your Christmas lights that are out side and if you use LED lights its easier to run longer on less power.


One of the reasons why I have been looking into solar is because power in this area isn't always 100% and having power that goes from on to off then back on 1 or 2 times really hurts your stuff.

So if you think of it this way if you rely on surge protect power bars to help protect your stuff and the good ones cost $50+ and you use say 5 to 10 around the house that's very costly and you could invest into a solar system for that amount so its like having a surge protect power system.

Toolage 87 said:

Pretty much as lot as you can seal the solar cells so that no air or moister gets to it could do a open layout like have it against your window so that the sun that hits it gets turned into power and such. Build the frame is just for people who want to make sure their cells will last a long time.

I plan on doing a spread sheet and finding out if there are things you can use to measure how much power goes into the battery bank and how much power you use and log it.

Doing solar is also good if you use those path lighting things but you could build your own system that they will last longer with and even because its Christmas you could use solar to help power some of your Christmas lights that are out side and if you use LED lights its easier to run longer on less power.


One of the reasons why I have been looking into solar is because power in this area isn't always 100% and having power that goes from on to off then back on 1 or 2 times really hurts your stuff.

So if you think of it this way if you rely on surge protect power bars to help protect your stuff and the good ones cost $50+ and you use say 5 to 10 around the house that's very costly and you could invest into a solar system for that amount so its like having a surge protect power system.

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...last year I wanted to go around and find broken path lights and things of that nature which people were throwing away. I wanted to collect the cells and then router a section of deck railing to accommodate them - kind of like a flush-mount energy railing Would be a great way to light up the stuff we have outside.

eye exaggerate said:

...last year I wanted to go around and find broken path lights and things of that nature which people were throwing away. I wanted to collect the cells and then router a section of deck railing to accommodate them - kind of like a flush-mount energy railing Would be a great way to light up the stuff we have outside.

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Actually if you have the tools you could set up a uber cheap solar system using old solar path lights that people throw away because the bulb is burnt out or the battery isn't good any more. Mind you its not gonna put out crazy amount of power like the higher end cells will but its still a start.

Toolage 87 said:

Actually if you have the tools you could set up a uber cheap solar system using old solar path lights that people throw away because the bulb is burnt out or the battery isn't good any more. Mind you its not gonna put out crazy amount of power like the higher end cells will but its still a start.

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...I have the tools for sure. Those pieces I want from the discarded lights are usually all around 2 or 3" square... totally perfect to make a line of them work out - and it would look neat too. I'd have to check and see what the capability of individual panels would be for sure.

eye exaggerate said:

...I have the tools for sure. Those pieces I want from the discarded lights are usually all around 2 or 3" square... totally perfect to make a line of them work out - and it would look neat too. I'd have to check and see what the capability of individual panels would be for sure.

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If you have a tester test them. Also if you can get the amps and volts each put out and post a pic of them that would be awsome.