It’s been a a while since I put up an article. Life’s thrown a lot of things our way. My daughter has had a couple of medical issues, but we got through those and now things are getting better. So that’s allowed me the chance to get back to work on some projects and I’d like to talk about one of those today.
When the power is out any power is a plus. The ability to charge your phone, laptop or tablet can allow you to stay informed. If the system is sufficiently sized you can also run lights and maybe even your TV and satellite or cable box. Having a system such as the one I’m about to talk about also gives you portable power to take long on camping trips. Here it can perform the same functions as at home. Additionally it can run low draw DC fans at night to make a nights sleep more comfortable. So let’s get into the one I’ve built.
This system is built inside a nice Pelican case I found at a local surplus store. Skycraft is an interesting place that sells electrical and electronic surplus. They carry everything from transistors to wire. They also carry all manner of metal, containers of all sorts and tools. You never know what you’ll find when you go in and I spend hours in the place. Every time I go have to force myself to stick to the list, find what I need and get out. Otherwise a visit can turn expensive real quick. This case was only $65, here is a smaller one on Amazon for $160. As you can see you can save some real cash by shopping at unconventional places. The case was perfect for my project so I immediately scooped it up. Of course you can build one of these systems to any size you want. In this case I wanted a larger case to accommodate the batteries and wiring and allow some storage. The case came with some pre-cut foam that I utilized to support the batteries.
I went with two 50 amp hour sealed lead acid batteries. By wiring these two in parallel it gives me 100 amp hours at twelve volts. This is about the same as a good marine grade deep cycle battery. The two I went with are for powered wheel chairs. These are high draw pieces of equipment and I knew batteries designed for such use would do everything I needed. These are not cheap batteries though. When it comes to batteries you get what you pay for and I needed a battery designed for significant draw and recharge cycles. Keep in mind that lead acid batteries begin to significantly degrade when discharged below 50% before charging. This starts to lower the service life of the battery. Charge/discharge cycles are what determine how long your batteries will last.
The batteries are installed in the bottom of the case so that when the handle is extended and being drug around the weight is at the bottom. This is also the reason I went with sealed lead acid. I could have gone with AGM (absorbed glass mat) batteries often referred to as gel cells but price was a consideration. To configure the batteries in parallel you connect positive to positive and negative to negative. If you reverse the polarity in your connections you double the voltage while halving the amperage. So with these two batteries you would have 24 VDC with 55 amps. The reason is that the two batteries create one cell in such a configuration. As they are I still have the twelve volts but double the amps to 100, that’s a lot of power.
Also inside the case are the solar charge controller, terminal strip for wiring, solar panel connection, 12 VDC connection, volt meter and a USB power connection. I also keep a package of replacement fuses in the case, that way I’ll always have them. Additionally I keep a small 700watt inverter and USB light, I’ll cover these more later, let’s talk about the solar.
For this system I bought a kit off Amazon. In this case it’s a Renogy 100 watt panel with charge controller. For $170 it’s a good deal for such a large panel. The charge controller is a nice bonus as well as the cable that comes with the kit. I’m sure you’re wondering why such a large panel? There’s a couple of reasons. Firstly is the fact that I’m planning a larger project and this was a good chance to test out the panel. So far all I can say about the system is that’s it’s fantastic. I’ve only actually used it once to charge the batteries but it did a great job. It’s nice to know the controller will prevent the batteries from over charging.
For the connection to the case for the panels I went through a number of options. Finally I settled on Anderson Power connections.These are fantastic connectors and way better than the old cigarette plugs. They can be had in any amperage rating and make twelve volt connections very easy. In this case these are 45 amp connectors. You do need a special tool to crimp them but it is fairly cheap. As you can see in the photo below you can also get bezels for the connectors. These make the installation nice and neat. I added a piece of heat shrink to the end running to the panels just to make sure they stayed together. The neat thing about the Anderson Connections is they will slide together and stay connected so the shrink was purely aesthetic.
Above you can also see the bezel containing the volt meter, cigarette connection and the two USB plugs. This too I ordered from Amazon and is a pretty nice piece. So many of our electronics charge via USB that having the ability to do do right from the case is really nice. Not to mention you can get really nice lights that run off USB. These are fantastic for camping or during power outages. Just plug them in and you’ll have plenty of light. The red button beside the bezel is a power switch for the meter. It’s not needed, the meter draws next to nothing but I wanted to be able to turn it off. If you’re like me and managed to break your addiction to alkaline batteries and go with rechargeable cells instead you can also keep those topped off. Most chargers have a 12 VDC input. Simply use that and plug it into the case and you’re charging cells for flashlights, radios or maybe a favorite toy for a little on in the house.
Here you can see the two USB connectors. One is a one amp and the other is a 2.1. So you can charge some of those high draw devices as well as a phone at the same time. I plan to add another set of Anderson Power connectors for the small inverter. That way I can just plug it in and not have to open the case and clip it on. The addition of the inverter gives the ability to run numerous 110 VAC devices, including battery chargers if yours do not have the 12VDC ability.
Here is the small inverter and the light. The inverter can be had in a number of sizes and this is fully capable of running my TV should I need it. The light you see is an awesome piece of equipment. It’s called a SunJack Camp Light. It comes with a switch built into the cord and will light up a room like a 40 watt bulb. During a power outage a couple of these will provide all the light you need in your house. If you have a portable USB power supply like the UniFun I have you can place these lights anywhere. These little power supplies are great, holding 10400 mah of power you can run one of these lights for days. Having the ability to then recharge it from your solar station is a huge plus. At $20 bucks it’s a great investment for a waterproof and rugged piece of gear that will keep phones charged (it charges my S4 with an additional battery built into the case two times) as well as running lights.
In the last article I did I demonstrated a way to pump water if the power goes out and you’re on a well. This power system will run that pump with no problem. Add a Anderson Power connection with the proper rating and fused sufficiently and you’re in business. And let’s talk about fuses for a moment. In the picture of the open case you can see a number of fuse holders. Everything is protected by fuse. The incoming power from the panel is fused. The connection from the charge controller to the batteries is fused and every device output is fused. It is very important to properly fuse all lines. The last thing you want when you’re in the dark is a fire in your only source of power. Not only will you lose your power station you could lose you home and possibly lives. If you’re unsure about proper fusing consult an electrician and make sure everything is properly protected.
A little planning ahead of time can make a power outage a nice experience. Time to hang out with family and play a game or maybe read a book. Knowing that the basics are handled and you’re not going to be stumbling around in the dark. When there is no power, a little power goes a long, long way. Get creative and see what kind of system you can come up with. They don’t have to be as big as this one, I just have a habit of going to extremes! If you have a system, post some pics of it and lets share some ideas.