Tuesday July 27, 2021
10:47 AM (PDT)
|What are your plans if the power goes out? Be it from an ice storm, tornado, system failure, or something more widespread, what would you do? Electricity keeps us comfortable, cooks our food, provides us entertainment, and keeps us safe. If the electricity goes away for more than a few hours, most people don't have a plan.|
|The easy answer is use a generator, or hope someone else will help you out. Generators run out of fuel, and waiting for someone else (FEMA, anyone?) to come to your rescue is not a plan. You are ultimately responsible for your own preparedness and safety.|
|Well, this is a question I've asked myself. I am a nerd, always will be. The lack of power is a major loss for me - I use computers almost constantly, and we watch a lot of movies. Well, we have a generator, but as I mentioned above, they run out of gas. They break down. I wanted to have renewable, clean power that didn't require fuel or too much maintenance.|
|So, I got my mad scientist on.|
|I designed and built a solar system. It isn't enough to power the house or anything, budget wouldn't allow that. But, it is enough to power laptops, charge batteries and cell phones, power LED lighting, I should be able to run a TV and DVD player too. It uses a 120W solar panel to charge two 115Ah deep-cycle batteries for running things at night. If I'm careful about what I run from it, it should be plenty of power to make life more comfortable if the utility power is out.|
This is the core of the system. It contains all of the
electronics and power distribution:
Here it is, with the lid open:
And with the battery cables taken out:
This is the bottom of the case. This is the high-power
protection and distribution. The Morningstar 30A PWM
solar charge controller is at 12 o'clock. The 1500W
power inverter is at 3 o'clock along with its 100A fuse
directly in the center, on the bottom. The battery
disconnect is at 9 o'clock, along with the high-power
bus bars and the main 125A fuse. Between the disconnect
and charge controller is the 60A fuse for the distribution
Here are the solar and ground cables. I have 50 feet of
USE-2 cable that goes to wherever I place the solar panel.
The green cable is the ground wire, that I attach to a
temporary ground rod.
This is the top of the case, the low-power distribution.
In the upper-left corner, the grey box and canister is the
lightning protector. If the panel gets struck, this device
will shunt the lightning to ground instead of through the
system's electronics. The low-power distribution panel is
in the upper-right corner, it is actually a marine fuse
panel that uses ATC fuses. The box in the lower-right is
a homemade USB charger - I don't need to have phone
chargers to charge my phones, I just need USB cables. The
small bus bars in the lower-left are where the solar
cables terminate. Also of interest - the gooseneck LED
light, so I can operate the system in the dark.
The USB charger includes four charging ports, each pair
capable of providing 3A of power.
This is the interior of the USB charging system. The two
black boxes at the top of the photo are DC-to-DC converters,
used to convert the 12-15VDC to 5VDC for USB charging. The
breadboard in the center holds two resistor bridges. The
bridges are necessary to provide approximately 2.7VDC and
2VDC to the data lines of the USB ports - simply applying
the full 5VDC to the power lines isn't sufficient. The
lower voltages on the data lines tell the USB device to
go into charging mode.
|So, there you go. That's my solar system. I intend to keep it charged and use it as a backup power source around the house, and as a power system for camping. In an emergency, it will allow me to run power tools sparingly, as well as keep our small electronics running and charged, while providing lighting via high efficiency LEDs.|