Total Wattage/Amperage Generated

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Total Wattage/Amperage Generated

Post by Sjcaron1 » Thu Feb 26, 2015 7:18 pm

Hi Troy,
I am a new user and have been watching your videos off and on for the last couple of months. I am currently planning on building a Solar array for off grid generation (1Kw-1.5Kw). In viewing your videos I see you discuss the Voltage, Wattage and Amp hours being produced on your solar charge controller. What i keep wondering and maybe you could give this information occasionally in a video is what is the size of your setup (Ie. 700w being produced from a total of 915w or 35w of 915w). I know from the videos that I have watched, that you have a Harbor Freight set of panels that are 45W in total. I also have watched the video that talks about the 2 - 200w panels and the 2 - 235w panels (870W total). I also know that you have 2 wind turbines and golf cart batteries (not sure of capacity). It is interesting to see the computer logs showing total watts and amp hours, however it is difficult to discern comparison wise total potential vs total currently being produced. Also it would be helpful to know what is hooked to what. Are the harbor freight panels hooked to the camper? Are the 2 wind turbines run to your current living space? What goes where and what is producing power for your current living environment. Also it would be helpful to know your relative location (State, Closest City). i am sure this information has probably been discussed before, but I have yet to run across it recently. The reason for all my questions is I am trying to surmise what kind of production i can anticipate from the array that intend to build. I enjoy your videos and look forward to the real life information (positive and negative) that is helpful and informative. I would enjoy talking to you sometime about all the knowledge you have acquired in a real case scenario. Sorry if this is long. Keep up the good work and I look forward to your videos.

Ryan Romero
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Location: Lafayette, LA

Re: Total Wattage/Amperage Generated

Post by Ryan Romero » Sun Jan 31, 2016 12:09 am

Your right to ask location, Yours in particular. As your location can determine how much direct (MAX) light you will get. NOTE: Solar NOON is not 12:00. Its close but not the same. This is when the sun is Directly over the panel : MAX SUN. There are charts online (google it) to determine how much sun you get : though it may say 4-7 hours, you will get more just not at max power. BUT, for reason to determine in general; always use the hours they state because it takes 1.5 the power you use, to put it back in your battery. If you use one amp of power, ruffly it will take 1.5 amps to put the one amp back in your battery. Here is a example of how to figure out what your require. For Example only :: Lets say you only want to power 1 item and its a TV that requires a total of 500 watts per hour running on 120 volts. There are three formulas you need to know for anything solar : VOLTS X AMPS = WATTS ; WATTS / AMPS = VOLTS; WATTS / VOLTS = AMPS
You may see this online written like this : V x A = P ; P / A = V; P / V = A (P is for Power or Watts)
So what do you need to power this one TV and for how long. Lets just say 12 hours you need it to run continuously. Well your battery bank IS FIRST and is MORE IMPORTANT than the panels! It also requires more maintenance if you want it to last. In addition you should never go below 50 % battery power ever!, I never go below 70%. So lets figure the bank out : one TV requiring 500 watts per hour, Running for 12 hours. 500 x 12 hours is 6000 Watts. If your battery bank is not to go below 50% you need Double that, so 12000 watts running at 120 volts. Lets turn this into amps to see how big the bank must be. 120 volts / 12000 watts is 100 amps. So you need a 100 amp battery so that you will not go below the 50% mark. So lets say you purchased a single 100 amp battery, and your going to use 50 amps. Remember it takes a general average of 1.5 of what you take out, to refill the battery (its because the battery cant take it in at once, it can only take a charge at a certain rate, therefor causing it to take longer). Now lets say your ZONE where you live gives you 5 hours MAX sun. You are going to need get enough panels to produce 75 amps in 5 hours. (each panel tells its in take in amps, but you can convert) For example : if the panels are 12 volts at 250 watts, Then you can figure out the amps by using the formula I gave you : 12 volts / 250 Watts = 20.8 amps per hour it will create. Just because a item says it will create X power does NOT mean it will. I usually reduce the manf numbers by 20% when you purchase to make sure you dont undercut yourself. But we will go with the manf for now. So a single 12 volt panel at 250 watts will produce ruffly 20 amps x 5 hours of sun is 100 amps. Enough to recharge your battery. Also note : at that rate of a 12 volt panel producing that much power you need massive wires, This is why you get a panel at 24 volts are higher (Personally I use 24 volts so I can use smaller wire) but my bank is 12 volts! Well my Charge Controller converts the 24 volts to 12 volts to charge my batteries. You also need to get a inverter to convert the power from 12 volts DIRECT CURRENT to 120 volts AC current. This device ALSO uses power, ruffly 1 to 5 amps per hour for doing the conversion. There are different types and if your using a compressor or electronics get a TRUE SINE Power Inverter. This is the same Wave length of power that you get from the power company, which is safe for sensitive equipment. When it is possible use the largest wire you can for any type of device, because the larger the wire will prevent you from having a power lose in small wire and prevent overheating. There are different Charge Controllers as well, get the best one you can afford as this is the one item you want add too. Batteries and Panels you will add etc, but the CC usually is the one item you stick with. I have one expensive one a midnite charge controller, and I bought a few cheap ones. (There backups) If CC fails, I wanted something I can use temporarily as there are some for around 30 bucks. Mine cost 700 for my Charge Controller with the extras, my backups were 30 and I have two. Well I hope this helps explain how to figure out your system, Using the formulas I have given you. Step 1. Get a list together, Figure out your total amp or wattage of all items your going to use and how long. Step 2. Figure out how many batteries your going to need by amperage. Step 3. Figure out how many panels you need to resupply your batteries. Step 4. True Sine Power for sensitive electronics : Modified Sine Wave for Cheap / Replaceable Equipment Step 5. A Charge Controller that can convert your panels output to your batteries voltage (EX: 24V panels and 12V batteries) It would have to convert 24 volts DC to 12 volts DC to charge your batteries. Step 6. Use the largest possible wire between devices to prevent heat and power loss.

That is about detailed I can get to explain this for your understanding, however if you have more questions I'll help with them. Something to also note is that you should read as much as you can before you begin, especially the SAFETY GUIDES! If you hook them panels up in the day, they produce enough power to be FATAL, take it seriously when doing this. In some cases 100 more times more deadly than what is in your home currently. This is DC with EXTREMELY high amperage that can injure you are someone near. I personally did mine during the day, but I covered them with a blanket while working on them so that they would not produce any power. Please be safe!

Your Friend in the world of solar,

Ryan Romero,

Geaux Solar!
Ryan Romero,

The Cajun Rocket Scientist

Geaux Solar!!! :idea:

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Re: Total Wattage/Amperage Generated

Post by techman » Tue Feb 02, 2016 9:05 pm

My setup is less than optimal. I have 600 watts of solar panels but am only pulling in just over half that. In part due to all the trees but also in part because my panels are not angled for optimal solar collection due to the wind out here. They blow right over on their faces if I angle them any more than they are. The wind here is brutal!!!!

Do NOT take my solar power setup as average. It is way less than average. I will be improving it with time. I will be putting them up on a ledge over the tiny house soon.

The wind turbines are currently not connected due to the wind tearing up my tower last winter. I will be building a better tower soon.

If your system is set up optimally you should see about 1,000 watts of solar from 1,000 watts of solar panels in peak sunlight. It varies during the day a lot though.

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