Lets give you some solid basics about off-grid solar power -
  by introducing some of the big topics
 

  What is a solar panel and how does it make electricity?

  What is a solar panel and how does it make electricity?

  A Photovoltaic (PV) solar panel is a semiconductor device that is made the same way that transistors
and computer chips are made. It is the exact same material -Silicon Carbide with trace amounts of other   chemicals which enable the silicon (glass) to make electricity from sunlight that hits it. The "photons" of light from the sun -liberate electrons from the atoms in the panel's layers and these are collected by a metal grid on either side of the panel. One side is positive and the other negative. The trace amounts of other chemicals in the silicon give it a negative or positive affinity. These different layers are on top of each other in the panel.
Over many decades, the efficiency of the panel will go down a bit. That said, it will produce over 75% of it's original output for at least 30 years.
 

  A "Grid -Tie" system is one which is directly connected with the commercial power lines. There are normally no batteries to store power for cloudy days in a grid-tie system. The advantage is that you don't need to buy batteries. the dis-advantage is that your system will be shut down during general power outages and you will still need a generator for emergency power. Grid-tie systems "spin the meter backwards" during the day and feed power into the commercial power system. In the evening, you draw power from the power lines as usual.
Thus, you only pay for the differential between what you made during the day and what you used at night.
Grid-tie system require a NABCEP certified installer and inspection by the power company before use.

With an off-grid battery-based system, you are autonomous from the commercial power lines. Your system charges a bank of batteries during the day and you use that power at night. Homeowners are allowed to do electrical work on their own homes in most jurisdictions. Thus, you could build an off-grid system without an electrical inspection in most areas. As well, you can build any size off-grid system. You might build one only to power your freezers... or power a weekender cabin. You can also build portable off-grid systems on a trailer.
The downside to off-grid is that you need to buy batteries every 10 years or so. If you don't use no-maintenance batteries, you'll also need to keep them topped-off - so there is a little maintenance involved.

People who just want to cut their electrical bill often opt for grid-tie systems. Those who want to go "off-grid" and be totally self-sufficient opt for off-grid battery-based systems. Federal tax incentives give credit for both types. The tax credit is only for the actual hardware and not labor. Since grid-tie systems normally require a professional installer, a much smaller parts of your investment qualifies for the tax credit with grid-tie.
 

  A Charge controller is the device that regulates the charging of your battery bank in an off-grid system. It is just like a battery charger for an automotive battery- but its a lot smarter. These controllers monitor the output of your solar panel array and charge the batteries in several stages. Batteries are best charged more heavily at first and less strongly as they top-off.

MMPT type charge controllers are the latest technology and are able to convert 30%-40% more power from the solar panels into actual battery charging current (compared to the older traditional type chargers. They optimize the battery charging - almost continuously. MPPT stands for Maximum Power Point Tracking. The charge controller must know what the battery bank voltage is. This is set by jumpers on the controller or on the LCD screen of the controller. Each controller has a maximum current it can handle and a maximum voltage input. Having the ability to take a higher voltage from the solar array, it allows you to configure the solar panels for a higher voltage -so that you loose less power on the wire run from the panels to the charge controller. Many controllers also store data from each day. You can also install remote control "heads" so that you can control it from inside the house.

The higher the battery bank voltage you are using, the more power a given charge controller can handle from the solar array. That's because since the controller has a fixed maximum current in amps, when you multiply the battery voltage by that maximum current- you get the total wattage it can handle. The higher that battery voltage, the more watts of panels it can handle. Amps X Volts = Watts. Typically, you use either 12 /24 or 48 volt battery banks. 24 volts is a good balance an popular battery bank voltage.

Cost for medium-sized charge controllers ranges from $250-$550. This is for systems around 2000W. For small systems of under 1000W, you might choose a traditional charge controller of much less cost.
 

Battery quality is determined by the size and thickness of the lead plates and the volume of electrolyte. You are paying a price for the lead, so the bigger they are, the more they cost. With wet-cells, you might use golf cart batteries, trolling marine batteries or industrial wet-cell batteries from fork-lifts etc. You should go down to your local industrial battery supplier and see what the best value he has is. You can configure batteries into any voltage "bank" you choose, so really, you can get whatever the best value is and then configure it using jumpers to your desired voltage. The larger the batteries you buy, the less jumpers you will need, so this saves time and money.
 

So, now you have to wire up the batteries for your desired voltage and amp-hours total. Batteries add up their voltage when you wire them in series (plus to minus) and add up their amp-hours when wired in parallel (positive to positive and negative to negative). So, you first make a first bank of individual batteries in series to get your desired voltage (2 if they are 12 Volt and 4 if they are 6 volt to get 24 volts). The amp hours of that "bank" are the amp-hours of one individual battery. (REMEMBER: you cannot mix batteries of different types or age in the same system). Now you have to clone that first configuration as many times as it takes to add up the amp-hours for your total system. You then wire these clone banks in parallel to get your desired amp-hour total. I show exactly how to do this in the video. You have to be VERY careful wiring these banks. You have to wear safety glasses, no jewelry and tape all the handles of your tools with electrical tape. I don't suggest you attempt this after only reading this briefing. This is the only dangerous part of building a solar system.
 

Calculating what you should buy is determined by either your maximum budget or your power needs (if you have unlimited $$) You will typically make less than- or just enough for your needs. I show the exact methods for calculating your outlays on each hardware item in the full course.
 

Amorphous panels are made by coating glass with photovoltaic material. These are cheaper to produce and have some issues with longevity and consistency of output over time. If made by well-known manufacturers, they can be a good choice. You'd like a warranty!

Thin Film technology is the latest craze. It uses only 10% of the materials as a traditional panel and can be used on unconventional surfaces (such as roofing tiles). Thin Film panels are becoming available and when made by reputable companies, they are a good option.

The most important things to desire in a solar panel is a good value, a warranty and a reputable manufacturer.
 

Another AC dis-connect box is used at the input to the battery box. This is a good place to install a Lightening arrestor. (also all covered in the video)

Remember, panels CANNOT be turned off when in the sun. You should NOT connect the connectors together while they are in full sun. This will cause a spark and damage the metal inside the connectors. Do your wiring in the evening.. at sundown. You can also cover them all with cardboard. You only do the connections once..

Note: When the sun comes back out from behind a cloud, there is a temporary magnification effect while it emerges. This can result in a short-term rise in voltage and current from your system. You will see this on your charge controller meter when it happens. This is why you leave a little "headroom" in the voltage your panels are wired up to provide - so as to not exceed the maximum voltage input specification of the charge controller. The charge controller (MPPT) will convert all the extra voltage from the panels into charging current at the desired battery bank voltage you are configured for. You set the charge controller for the battery bank voltage you've chosen- with either jumpers or selections on a menu- depending on your brand/type. 
 

Lead-Acid deep-cycle batteries require maintenance. Batteries with liquid electrolyte (sulfuric acid) require
filling periodically... just like a car battery does. The more you charge and discharge them, the more they need to be topped-off. You check the acid level by removing the battery's caps and visually checking the level.
You need to have safety glasses on. You might as well use rubber gloves. Some people are more sensitive to sulfuric acid than others. You will be topping-off the batteries with distilled water. Never add battery acid.
NEVER let the electrolyte get below the tops of the actual battery lead plates. Use a plastic funnel to fill the battery cells. DO NOT wear metal jewelry or a watch when doing this. Also, the acid will eat through cotton clothes. Wear old clothes. Slowly fill each cell to about 3/4 inch from the top. Do not fill them all the way to the top. Acid will bubble out during charging. If you see your charge controller voltage go up to 15V or more when charging, it is a good indicator that your batteries are low. Don't let it get to this stage. Check them every few weeks.

Wipe off any spilled acid or water on the battery tops with a disposable cloth. You should also consider spraying anti-corrosion spray on the battery terminals. An old trick is to put two shiny pennies near the terminal. These will draw off any corrosion and can be replaced when shot. There are also treated red and green anti-corrosion disks that you can buy and they go under the terminals.

Once a year, check tightness of all connections... they loosen up sometimes. Put electrical tape over all your tool handles so they cannot short the batteries out if you drop them.
 

The solar panel array needs to be as perpendicular the the sun as possible. There are two paths involved.
First is that the sun's path across the sky changes from season to season. The second is that the sun moves from east to west during the day.

Your panel array needs to be adjustable for seasonal change. The sun's path is nearly overhead in Summer in North America and quite a bit lower in Winter. Thus, we are talking about the panel's angle to the horizon.
You can do these seasonal adjustments a few times a year. The more you do them, the more energy you will make. Really, twice a year is fine. This is because the panels have a coating on them that captures off-axis light well. In Summer in the northern hemisphere, your panels will be almost horizontal in southern latitudes and somewhat less than that as you move north. If you are roof mounting panels and cannot adjust them, you should position them for the Winter sun angle. Winter has fewer hours of sunlight and you are indoors more using more energy... so favor the Winter. The course teaches you exactly how to mount and adjust them for your location.

As far as tracking for the sun's daily movement, you can buy tracking mounts, but since the panels are so good at making energy from off-axis light, the payback period for the extra cost of the trackers is too long in my opinion. I opt for fixed mount panels. You do want to mount the panel array so that it is due south.
 

1. You have an un-limited budget and want to make ALL your current power needs with Solar.
2. You have a budget limit and want to make as much power as you can inside that budget.
3. You want to power a specific set of appliances or a cabin (small system design).

In each situation, you will be spending about 50% on your panels themselves, 10% on the Inverter, 5% on the charge controller, 25% on batteries and 10% on the hardware and wire. As panel prices drop (they are), you'll spend a slightly lower percent of the money on the panels themselves.

If you have an unlimited budget, know that to generate 1KWH of power a month, it takes 6 watts of solar panels (with 5 hours of sun a day). Check your electric bill and multiply by 6. Then look online for package deals on equipment at that level. With the limited budget, take 50% of your money and see how many panels you can get. Shop for best price and name brand. Then talk to the vendors about the rest of the stuff you'll need. They will be super-happy to configure all the parts required - inside your budget.

If you are making a small system for a cabin or dedicated application, you'll need to do an energy budget.
The videos tell you exactly how to make this calculation. It's not difficult but beyond the scope of this lesson.
 

The course is $43 total - free delivery in USA For international orders, it is $47 delivered

Choose your location.

Domestic USA $43.00 USD Outside USA $47.00 USD

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