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Feel Free to Distribute and Use this document; however I am not responsible for any action whatsoever that you do with this information. Secondly this is a “Living Document”, Meaning I will update the original file or Blog : from time to time and create a new/additional Blog/File/PDF to replace the old one. This is because new information may come to light that must be addressed or changes that need to be done that I originally missed. The way to know which document you currently have, you can look at the top left and see the date and number inside the Blog/File/PDF.
Occasionally, as my hobby expands and/or when I learn more that could be used for the DIYers; the document will be updated accordingly. Though no update will be made until I can actually prove it with my own hands by actually testing the process. I find this is the best way to make sure it is accurate as what I have seen everywhere on the internet they seem to know answers that they themselves have not actually done to certain aspects of things.
If you have a specific solar interest and its within my grasp to actually do the solar project: You may contact me about it here on the forums, and find out if its feasible and affordable. All the projects I want to do must be affordable and be done in baby steps, as I don't want anyone feeling overwhelmed as I did when I started.
I want to thank my wife as she aided in testing the equipment for me to verify that my current projects worked as it was suppose to and in addition has taken an interest in solar. I see this as a big step for any family with solar projects as they require maintenance and its very beneficial to have more than one person in the household that is able to make changes or some sort of maintenance if they are needed.
DO IT YOURSELF SOLAR SOLUTIONS
Table of Contents
The Nitty Gritty
The Math, The Work
The Status of Current Projects
A. Batteries 6 & 12 Volt
B. DC LED Lights & DC Ceiling Fan
C. The Control Box
D. The Reasons behind the Hobby
The TERMS of Solar : The Glossary
My personal experience with solar and my solutions explained in (my terms which happen to be simple layman terms). My learning experience, since I have picked up a new hobby...yes, solar. Solar power is my new hobby! I had began with lots of questions with so many different answers on the web, I had no clue as to what was right or wrong and if it would burn the house down. The best thing you can do is join a forum, watch a lot of youtube videos, and get a kit from the your local store and begin your learning of what it can or cannot do. Start small so that you have an understanding of what is possible and what is it your wanting it to do.
Again I am not an electrician or specialist in solar. I am not responsible for what you do at your house, this information is simply provided free as my own experience in my solar hobby project. I will answer all the questions I can to the best of MY knowledge, but if it is beyond what I know I would ask those in a forum for that sort of information and even more details there is usually someone there that can help. The forum that I use and is the most helpful in my opinion is http://solarpanelkitatharborfreight.ning.com/.
I have went to other forums and many of those people thought AC and DC amps should be about the same. I was astounded how they did not do the math to figure it out. The higher the voltage the lower the amps, the lower the voltage the higher the amps. When I was choosing a forum to get accurate help, I asked questions that I already knew the answer to simply to see if I would get the correct answer. Thats how I found the one I am currently using for aid when I need it.
OK so now lets get to the nitty gritty of figuring this out. So you're wanting to go solar and get off the grid or at least partial. I did say off grid meaning not using electricity from your power company. There are a lot of factors that go into this and with a blank slate it's hard to figure this out. Especially if all you see is $25,000 in the newspaper or some add on TV with call for a quote.
Before you even attempt to just jump into this, go to your local store or online store and buy the 45 watt kit or something similar to play a little bit so you can understand how exactly this works. These kits usually have a sale price within the range of 150.00 dollars for everything but a battery and inverter. The kit I purchased came with two lights and a charger controller that monitors your battery. Granted you will have to upgrade some of this equipment when you get more panels as usually the charge controller that comes with these kits are only good for handling a small amount of amperage.
The Math, The Work
Now that you have an understanding of it, you want to make your home solar? I will use my own electric bill as an example to make this easier to understand. On my bill it shows that I used a total of 1,500 kwh for 29 days. So how many panels do you need is the first question on most folks mind, as there are other factors; how much sun, how many amps you pull in, direction of panels, size of wire, size of panels, voltage your battery bank is at, inverting voltage, etc. All change the factors but for these examples I will NOT put those in the factoring math!
Well thats how much my bill is for 29 days ("1,500 kwh") so lets break it down. First lets turn your bill into watts. (Kilo meaning = 1000) (wh meaning Watt Hours) 1,500 kwh is the same thing as saying 1500 x 1000 = 1,500,000 watts a month! So lets divide that by the 29 days = 51,724 watts a day! Lets divide that 51,724 watts by 24 hours a day = 2155 watts each Hour! At this moment I own 4 Harbor Freight Kits or 12 HF panels each that can produce up to 15 watts an hour. And that doesn't mean it will, so when you buy your panels you need 2155 watts worth of power from the panels.
If I just bought only the HF Kits to rig this up @ 149.00 each. Divide one kit (45 watts) into your consumption. In my case would be 2155 an hour. So: (1 kit) 45 watts / 2155 watts (1 hour usage) = How many kits = 47 kits! And that is not the just of it, you actually need more for when the power changes to AC you lose some of this. This is just a base to work off of, Granted you can buy bigger panels with more watts for less money. However I am using the HF kits as my example because most folks start with that and expand on it.
You will learn more about larger panels soon enough, meaning you don't need 47 kits and will be more like 10 larger panels. Don't forget at night you're not producing any power, take this in consideration when you're thinking about this. WOW. Still wanting solar? Don't throw it out yet! There is a solution to the problem! What is it? It is YOU, yes you by changing your habits! Change to low wattage bulbs, possibly go DC on some items instead of AC, Unplugging equipment when not in use. Not just turn it off and why is this?
A regular Incandescent bulb at 100 watts versus a 3 watt LED bulb! Do you realize how much savings is that on power? Well to figure this out, there is something you must know. Amps, because now you know you need to have a battery bank to produce power not only in the daytime by at night when there is no sun. So lets do some math; Amps = Watts / Volts so if you had a 100 watt bulb lets do the math for it:
?= 100 watts / 120 Volts AC That means .8333 however your Source (Battery Bank is DC)
You must see what the DC Draw is on the battery bank! That means in general you multiply the AMPS by 10. So .8333 AC amps x 10 (10 is your multiplying factor) to explain where I got this general number is (120 volts / 12 volts = 10) so in effect (.8333 AC AMPS x 10 Inverting Factor) = 8.333 DC amps. So your battery every hour to run this single 100 watt bulb will take 8.333 DC Amps. If you had a 9 amp hour battery, that's ONLY one hour. Note: Your Inverter also draws amps to change DC current to AC current. Smaller inverters average about a 1 DC amp draw from the battery.
Again, lets try the 3 watt led bulb. Same Formula. (? = 3 / 120) -> (.025 = 3 / 120) Now convert to DC to find battery draw. (.025 x 10= .25) (((WOW. only .25 Amps on DC))) You can run 30 Lights (3 Watt LED) which is equal to one 100 Watt Bulb. So yes, you can change to low wattage LED lighting and this can help determine your battery bank size by knowing how much and size you need for your batteries. Personally for me: I want to start small and change ONLY all my lighting first, nothing else.
However, I now currently run my LED lights with a .3 DC amp rating at 12 volts (basically they are RV type lights) And I have : Bedroom # 1 (1 Lights) Bedroom #2 ( 2 Lights) Bathroom (2 Lights) Utility and Hall ( 2 Lights) Living Room (4 Lights) Kitchen (3 Lights) For a total of 14 LED Lights @ .3 Amps each on 12 Volts. (.3 AMPS x 14) = 4.2 DC amps per hour. When your see Watts or AMPS on a product that usually refers to one hour draw on AC current.
This means in my case, every hour I leave my lights on I will be drawing 4.2 DC AMPS. I have a total of 4 - 12 Volt 110 Amp Hour Batteries, I have them wired in parallel which makes them like one big battery. Meaning its like saying I have one battery at 12 Volts and 440 amp hours. So lets do more math. If I draw 4.2 DC AMPS in 12 Hours (One Night) (Assuming I leave them all on, which I won't. Only for example I say this) 4.2 DC Amps x 12 Hours = 50.4 Amps is what I will use.
So If I had 440 Amps and used (50.4). That means I used 50.4 of the 440 leaving leaving about 389.6 would be my remaining amps. You must also consider how low you will let your batteries go as different batteries have different levels they can go down to. But in general 50% battery life would be 220 amps or 12.06 Volts. My personal view is that 50% is the most I think that I would bring them down to. If you plan on doing a complete off grid system I would not bring the batteries below 70% so the overall life of the battery would greatly increase.
The next thing to know is that you need enough panels to replenish what you used. I just found out that I will be using 50.4 amps each night. So at this point lets figure out how many panels I need to get back 50.4 amps in a day to replenish the batteries back to full. Based on your location, determines how much FULL SUN you will get, amongst other factors that can change your amp take in. I invented my own teeter totter so my Full Sun I get is nearly the entire day giving me a superior advantage to those with stationary panels. Every type of Panel can take in different amounts so for this example I will used this data for >>>
Again, I am using the perfect world scenario by going with what the box and manuals say if you have perfect sun and such. Cloudy days can effect this greatly as well as your location on the planet. I am in Louisiana which is actually close to the equator which is good for me as I will get more sun than many other states. There are charts online that you can find to see how much sun you will get if you decide to go with stationary panels.
If I have 1 kit which consist of three panels, which produces 45 Watts & 3 Amps per hour. And Lets say you get 5 Hours of Good Sun. This means this single kit will give (3 Amps x 5 Hours= 15 Amps a Day per kit. So 50.4 amps used divide by 15 amps per kit will tell you how many kits you need. So (50.4 DC amp usage / 15 amps a kit per day = 3.3 or “4” HF Kits) This means I need 4 kits to produce enough amperage to replace what I used . However, though I only used 50.4 it will take double that 100.8 to put back the 50.4 or to say its completely full once again. Your battery simply can't take it in as fast as you draw it out, so in this case you can say you need to put 100.8 amps back in and will require 4 kits and a total of 10 hours (2 days) to get 120 amps (In perfect weather conditions). Take in mind this is only for my 14 DC LED lights in my home. If you're curious as to where I obtained these DC lights, I purchased them from from an online dealer. I paid roughly 15 dollars for each LED light that has 24 LED's. Specifically I got the ones with a deep cover that puts out a lot more light than I was expecting to have and I am extremely happy with these.
Now, I am using these lights and do not use the max amperage draw. What I am using is roughly about 15 amps a night, because I don't leave them on unless I need them. This means I can replace what I use in a day or so with 1 kit. Currently I have my 4 solar kits or 12 panels set up to receive around 12 hours of sun which produce about 160-170 amps a day with them following the sun. If I did not have them following the sun, I would get 5 hours and roughly about 75 amps. A significant difference for it to follow the sun as you can see how this is done further down in the document.
Eighteen (18) gauge wire is what I used for wiring these lights, I was able to use a small gauge due to the lights drawing a very low amperage draw. Remember that the longer the distance and the higher the amperage draw your product uses, the larger the gauge wire you will need. It is always best to have too large of a wire than to small of a wire, in DC current if your wire is too small for the current it can get hot quickly and start a fire. Speaking of fires, it is also good to protect you and your home by having fire fighting equipment such as a fire extinguisher.
I have plenty of batteries to do the job, but you must keep them charged. Not to mention if you have some bad days with even less amps taken in, it could take even longer to charge. This is why some folks get something called a float charger, which runs off commercial power and can be used to keep your batteries charged while your solar is not producing enough or any power. It aids in keeping your battery at the correct voltage if the sun fails to reveal itself or if you're in a bad location for sun. When using this, you should disconnect other charging devices so you don't have two charging devices connected to a battery. Do not have it hooked up to your solar setup, while doing this; If the sun does show itself while you're trying to float charge it could cause damage to your equipment. There are many different kinds of float chargers, make sure that you get one that is suited to your battery setup.
So like I said, All things must be considered about your habits like leaving your TV off but plugged in, It still draws electricity. If you used a power strip to turn the TV off, the current would stop at the surge protector and the TV would not continue to draw power. This is on all or most products that continue to draw electricity even being off. There is a device you can purchase called a kilowatt to find out if your product does this. Other things like having a habit of leaving lights on, that you should turn off when not needed. On my personal view about my LED lighting system, I probably will have no more than 4 Lights on at any given time, not all of them. That being said, let me show you the math if my habit is good. (.25) amps per light x 4 lights on = 1 amp per hour. I will run it for 12 hours (One Night) so (1 x 12= (12) amps a night)
"Kill A Watt" Electric Monitor
I own only four Harbor Freight Kits at the moment which means I get 180 watts per hour and based on what we used prior of 5 hours and 3 amps per hour. This means I will get roughly 60-75 amps before the teeter totter and only used 12 amps a night. In this case, this is good because the following day I should be able to fully charge my batteries again. Solar panels are the same thing as that battery charger you use to charge your car battery. The only difference is that the type of battery you use it designed to lose power then recharge many times. Your CC or Charge Controller is what sends the correct amount of amperage back into the batteries without hurting them. Without having this, too much power could go into a battery and cause it to overcharge possibly even explode. This is only a different method to do the same thing as your car has lights, AC, Radio, etc and your alternator in your car is what sends the power back to the battery.
So then, I hope this document helped someone, as when I first started I thought I would never figure it out because of the broad amount of data and unsure of what was right and what was wrong. Knowing the formulas and having charts is what helped find the answers I been looking for. As for the advanced solar users who see this , A word of ammetur advice: do not explain in a manner way over a beginner's head, as this happen to me and I did not understand and even got to the point after doing research proved them wrong because they thought they knew it all, I wrote this for those who are just a beginner in the solar world so that they know the best thing they can do is Learn as much as they can before investing in something they may or may not need. I over purchased on some things and under purchased on other things. If I would have had the information first, I could have saved some cold hard cash which we all need.
And here is the solution to most answers in the form of formulas that helped me because of those who went over my head at the start.
(Amps = watts/volts), (Volts = watts/amps), (Watts = volts x amps)
Again, if you have questions. Ask before you try, someone already did it and it's best to get a answer with a known outcome. Don't just plug stuff in and hope it works like you see on youtube. Do the math, get the answers before you spend the money and attempt the project at hand. Just to give an idea of what I mean about planning prior to purchasing, I made this drawing before any purchase. Though I did not do it exactly like it, the idea of what I have done is very similar. I checked prices, figured out the wiring and most of all made sure it won't blow up!
So now that you have a idea of how this works. I will show you a few photos of how I expanded and increased my own power on the solar side. My original idea is that the equipment alone would be portable such as the Charge Controller, Batteries, PDU “Power Distribution Unit”, etc.
First my original setup below, all the electronics on a portable cart except the panels themselves. You can see the wires coming from the solar panels going the combiner at the top left of the photo. I had two kits at this time, one on either side of the shed. I did it this way so I would get both morning and afternoon sun. There is a 14 gauge wire coming out of that black box called the Charge Controller, that goes thru a drilled hole in the plywood that goes to the house to a junction box and then to the other lights with 18 Gauge wire inside the home. That is the one that runs the LED Lights in the home.
Then I purchased two more kits and was debating on how to mount them on the shed. I was trying to find out the best way to get the most hours of sun to maximize my draw from the sun. I knew of sun trackers but really don't have the money to purchase that for a low budget solar hobby. So I built something I dubbed a "teeter totter". If you're wondering what did this do for me power wise, I was very happy with the outcome of it. You see each 15 watt panel is suppose to produce 1 amp per hour of sun. If my panels where stationary I would get roughly five hours of sun, but now I get power from the sun from dusk till dawn so I get basically 12 hours of sun each day. That is double of what all the charts are on the internet for my location down in Louisiana. Secondly my panels output is higher than even what the manufacturer had said they can produce. I have 12 panels and as you see in the picture further down below at high noon I was getting over 15 amps almost 16 amps as if I had 5 kits instead of 4! The reason there is only a frame there mounted too and not a board such as plywood is that the panels can stay cooler without building up heat and the fact they can be flat faced to the sun getting the maximum amount of sun possible.
Above is when I began the project by making a 6 x 8 base with wheels for portability then added the 8 x 8 frame for the panels. Since the photo I added more braces and a control box as you see on the top right. There is now two battery banks on the cart, one of them consist of two 6 Volts in series to make 12 volts and my original four 12 volts.
As you see in the photo above and below, I call it a teeter totter because it goes back and forth like a kids see saw. I can move it easily with one finger so I ran a nylon twine thru and under to either side to cause a little friction so it won't spin so easily. My plan is to add an antenna rotator with a timer to make it move on its own, powered by itself. As Long as the teeter totter is facing N / S. The panels will be E / W with the sun which is very easy to set up. I plan on also adding a tongue on the teeter totter so that I can pull it with the lawn mower and currently move it with a nylon strap. I can move it fairly easy by pushing or pulling it, however I want my wife and kids to be able to move it with ease as well and living down south, if it needed to be moved to a new location due to weather such as hurricanes. Since the photo at the bottom I cleaned it up a bit, meaning I got the wires all in a nice clean look. I still have room for more kits or other panels which I plan on in the future getting higher powered panels which will sit in the middle and can tie into the existing setup. The picture on the lower right is what it looks like when it lights itself up at night using the HF light that came with it along with two LED strips I purchased from my local store.