Off Grid Shed Simple Setup but need help step by step

[KYY]

Hello Everybody. Hopefully I'll stay within guidelines.

I have a shed that I would like to setup with solar panels. I have no idea of my current Kwh per month, but I just want to use the system for regular drill/saw usage, shop lights, radio, air compressor. I go in the shed daily and spend about 15 minutes in it each time. Thus my usage is not that great.

Now, I'm getting ready to purchase 1 190W monocrystalline panel Model number is JTM 190-72M for $125 (local pickup). The single purchase is to help me "get started" into solar, or rather to get my feet wet.

I asked the seller of the panel if this was a 12v or 24v system and they said the Vmp rating on the panel is 36.5v and is more suited for a 24v setup.

I am wanting to do a 12v setup to already adapt with my current appliances as well as not electrocute myself in the process.

What would be the next step? Charge controller? What size would I need (keep in mind that I'll be adding more panels as my need continues).

What confuses me is I don't know how many kwh I use in this shed per month. I know I can purchase one of those wattOmeters at a hardware store and calculate, but I find that not as accurate as my needs in the shed change from time to time.

[ButchDeal]

you are not going to run a compressor, drill, or saw on any kind of a small system.
Growing solar is very difficult as the systems all have to be sized to work together. So starting with 1 190w module and growing it is about like buying a 1 cylinder engine and trying to glue on two more cylinders latter.

For off grid the monthly usage is less important (still handy to have) but the peak instant usage is important and the daily average is important.
You best bet is to grid tie this shed if you want to use these tools.

[Logan5]

Do not buy any of this junk. 12 volts is for toys and automotive, not for off grid. especially with such lofty goals of running a compressor. If you want 12 volts from a 24 volts battery bank, you use a step down converter. You need to read everything in the off grid section before you waste any of your money.

[organic farmer]

It seems that a lot of people want to buy one photovoltaic panel to play with. A friend of mine has offered to buy one of mine so he can play with solar power. Keep in mind that my panels are all mounted and wired.

In my town most homes using solar power are off-grid. We only have one home net-metering in our town. Whereas on this forum, it appears that net-metering is far more popular than off-grid setups. I have grid power available to me. By flipping breakers we can shift back and forth at will.

The only practical use I am aware of for a single panel is for remotely powering an electric fence. I am a farmer, I live in a rural area, where electric fences are popular.

[SunEagle]

One question I have is do you want to build a small off grid system or install a transfer switch for a generator which you asked about for in another post?

I will tell you that building a small solar/battery 12volt system is a waste of money and not worth getting your feet wet.

[Sunking]

I just want to use the system for regular drill/saw usage, shop lights, radio, air compressor. I go in the shed daily and spend about 15 minutes in it each time. Thus my usage is not that great.

Never going to happen. All you will do is throw a bunch of money away and wished you had listened. Do yourself a favor and hire an electrician to run you a line. A lot cheaper and acutally works. But trust us, what you plan is never going to happen.

To run a compressor off solar with battery you are talking 5 digits and batteries that weigh thousands of pounds. The solar and batteries will cost more than your shed. Roughly $10,000

Hire an Electrician and call it done. A 190 watt panels is good for charging laptops and cell phones but cannot generate any serious panels. You want air compressors, drills and saws, Try 2000 watt system with a 1200 pound battery that cost you $4000 every few years to replace.

Pay a Electrician $500 to $1000 to run a line with a 60 Amp Service. Will cost 1/10th what solar cost and works 24 hours a day 365 days a year with unlimited power. Solar cannot touch that.

[KYY]

Here are my responses:

Maybe I'm not explaining my intentions correctly. My shed is already wired from my home and I would like ot start "disconnecting" parts of my home (starting with the shed) from the grid. Install the panels on the roof the shed and build out more over time and finally take the panels current into my home. Inside the shed will contain the batteries (the non toxic kind) to keep them out of the weather.

I do not wish to spend $26k on a 44 panel system right now for my home (from what I was quoted). I wish to spend $1000/month on "parts" to build the system. If it means $1000 for the month of October to buy X number of panels, then $1000 for November for more panels or a charge controller, then I have them stored up. Right now buying 1-2 panels, researching on how to orient them on the roof, the parts that bring the panel to the charage controller of the shed etc etc is going to be valuable for when I need piece and part it together. It will take time, but it will be steady and not bankrupt me. I'm debt free and I do not take out loans.

Why would I want to go with 24v when all my appliances are wired for 12 volts? I'm not being smart, just wondering why every tells me not to go with this type of system. I'm the type that jumps at static electricity. Its my understanding since this is going to be a DIY, that I'm less likely to get electrocuted with 12v vs 24v... am I correct?

SunEagle, In regards to my other post, I do want a transfer switch so I can plug my generator into my home when the power goes out. Thus keeping my refrigerator and some space heaters up and going. And at a later date when I'm more knowleable be able to tie in my panel system to the main household... (when I build up to the 44+ panels).

Thanks for everyones replies!

[Logan5]

This 12 volt compressor you speak of. what kind of amp draw? I assume you are not running air tools from it? I also have many 12 volt appliances and they run fine on cheap step down converters. But since you already have grid power, you already know by switching to a solar battery system, you will never reach ROI, Not even close. and you will have batteries to maintain.

[SunEagle]

Here are my responses:

Maybe I'm not explaining my intentions correctly. My shed is already wired from my home and I would like ot start "disconnecting" parts of my home (starting with the shed) from the grid. Install the panels on the roof the shed and build out more over time and finally take the panels current into my home. Inside the shed will contain the batteries (the non toxic kind) to keep them out of the weather.

I do not wish to spend $26k on a 44 panel system right now for my home (from what I was quoted). I wish to spend $1000/month on "parts" to build the system. If it means $1000 for the month of October to buy X number of panels, then $1000 for November for more panels or a charge controller, then I have them stored up. Right now buying 1-2 panels, researching on how to orient them on the roof, the parts that bring the panel to the charage controller of the shed etc etc is going to be valuable for when I need piece and part it together. It will take time, but it will be steady and not bankrupt me. I'm debt free and I do not take out loans.

Why would I want to go with 24v when all my appliances are wired for 12 volts? I'm not being smart, just wondering why every tells me not to go with this type of system. I'm the type that jumps at static electricity. Its my understanding since this is going to be a DIY, that I'm less likely to get electrocuted with 12v vs 24v... am I correct?

SunEagle, In regards to my other post, I do want a transfer switch so I can plug my generator into my home when the power goes out. Thus keeping my refrigerator and some space heaters up and going. And at a later date when I'm more knowleable be able to tie in my panel system to the main household... (when I build up to the 44+ panels).

Thanks for everyones replies!

OK. I understand the desire for a transfer switch and a generator to power the home if you lose grid power. That is something most people should have.

BUT. I want you to understand that the cost to generate power from batteries will end up costing you 5 to 10 times what you pay for power from your electric utility or POCO (power company).

Also an "off grid" system is not something you can Grow. The panel wattage and battery Ah size has to be in balance with each other. Once you start you cannot just add batteries. The new ones will not last long because the old ones will shorten the life of the new ones.

As for the voltage of your appliances. When you use low voltage like 12volts your loads end up drawing high amps which require very big and expensive wires. The farther the load is from the 12volt source (battery) the bigger the wire needs to be because of something called voltage drop. Too much voltage drop (>2%) and your 12volts becomes 11volts which will not run your loads.

Running a higher voltage battery system 24v or 48v will allow you to use smaller wire size and allow you to build bigger battery systems. But that does not make it much cheaper then just using the power from your POCO.

[Mike90250]

.... Inside the shed will contain the batteries (the non toxic kind) to keep them out of the weather......

YES ! Tell me what they are, because I want some, and have not found any

[ButchDeal]

this is non-toxic

http://public.media.smithsonianmag.com/legacy_blog/potato-battery.jpg

not sure of the AH rating though.

[organic farmer]

... I wish to spend $1000/month on "parts" to build the system. If it means $1000 for the month of October to buy X number of panels, then $1000 for November for more panels or a charge controller, then I have them stored up. Right now buying 1-2 panels, researching on how to orient them on the roof, the parts that bring the panel to the charage controller of the shed etc etc is going to be valuable for when I need piece and part it together. It will take time, but it will be steady and not bankrupt me. I'm debt free and I do not take out loans.

Installers here quoted us a lot more

Our system cost a lot less

We did our system in small segments [panels, mounting, wiring, E-panel, batteries] as we could afford each segment.

... Why would I want to go with 24v when all my appliances are wired for 12 volts? I'm not being smart, just wondering why every tells me not to go with this type of system. I'm the type that jumps at static electricity. Its my understanding since this is going to be a DIY, that I'm less likely to get electrocuted with 12v vs 24v... am I correct?

In our town, I have looked at every solar power system here, and each system is way different from every other system.

There is no single best way, to do anything when it comes to solar power.

The system I like the best among all of our neighbors's systems is a 12vdc system. He did it in the 1980s and today it is still operating like a champ. I thought a lot about mirroring that system. It is a lot cheaper than what I ended up doing.