This is my second version of solar power. The first version can be seen in my other instructable
I did not take pictures as I was building this unit, because I had to make several changes as I was building. If I had this instructable would have 100 pages, so I am showing you my almost finished product.
On this first page you are seeing the closed tote. This tote is a Contico 50 gallon tote with locking lid. You can find these at most local home improvement stores. I did a lot of looking before picking this tote. It was the only tote that would give me the space inside and the strength to hold the weight of the components inside.
There are 5 meters in the front, this gives me the ability to know what is going on in an instance. Starting on the left, the first meter is the amp reading of the solar power that is coming from my solar panels. The second meter is the voltage from the solar panels. The third meter, under the lock, is a battery meter just like a golf cart would have showing the battery percentage in 10% steps. Meter 4 is the amperage being drawn from the battery bank. The last meter on the right is the battery voltage level. At a glance I can see the power in from the solar, power out from the battery bank, and how much power is in the battery bank. I got these meters on eBay, so there not the best but they work for what I am using them for. The amp meters are a little off. You can see that the 4th meter, amps from the battery bank, says 0.0. This is not correct, there is really an amp draw of about 0.5 because of the meters are on all the time. The meters wouldn't have to be on all the time, but I wanted them to be on all the time.
This is a partial list of what is in this box. Some of the items I will list are different then what is in my box currently, this is because there are better items to use then what was available to me at the time I built this box. Also everyone has there own opinions and needs for the items in there own box build.
These are the major parts.
- Box that I used. Here
-Batteries that I use, I fit 4 in the bottom of the box. Here
-Inverter. There are lots of options for inverters, the higher the wattage the more and/or larger the items you can run off it. My system is set up for 12 volt battery system, be sure to use an inverter that is made to convert your battery voltage to house hold voltage that you need. Some of these new inverters also have USB charging ports on them. in my box I have these items separate and it take up more space. When I need to replace my current inverter I will get one with more options, like USB ports and a remote power switch. Before purchasing an inverter do some research, there are lots of options. Things such as wattage size, input voltage, output voltage, pure sine wave vs. modified, and many other options.
12 volt to 110/120 volt, this link is just for one brand and there are wattage options.
24 volt to 110/120 volt, another example.
36 volt to 110/120 volt, another example.
12 volt to 220/230 volt, this is for higher voltage equipment.
24 volt to 220/230 volt, another example.
- Solar charge controller. These come in different sizes, voltages, and options. To know what controller is needed you need to know what input voltage from your panels will be and what output voltage to your battery bank is needed. This is an example of a charge controller. Here
- Cooling fans.I have fans installed to help cool the box when needed. Here
- Thermostat for cooling fans. Here
- Voltage meter. These come in different sizes, colors and voltage ranges. This is an example Here.
This is the left hand side. These 2 terminals have a T handle that screws off so that connections to the battery bank can be accessed from the outside of the tote. These connections are not metered through the battery amp meter on the front. I put these connections on for those “what if” moments.
What if I had more batteries?
What if I need high amperage DC, like jump starting a car?
What if the batteries are dead and there’s not enough solar to charge the battery bank and i need to connect a charger?
These connections can be used to put power in, or take it out. Just as if connecting directly to the terminals on a battery. It would be best to use a ring terminal held on with the T handle, but if I needed to use jumper cables I have a set of lugs that screw onto the bolts that look like battery terminals. This way I don’t damage the bolts.