Simple solar setup

There seems to be many people that have generators, and torches, but not everyone has a small, useable off-grid solar setup.

I just thought I would post some pics of my setup. Its not the best, there is room for improvement, but I hope that it helps inspire others to do something simple as well.
Constructive criticism is welcome, especially if you suggest / show other easy ways for others to do their own simple solar setup.

The idea is something that:
- you can use everyday
- highly practical in a power outage so that the family can function normally
- reduce the need for a generator, and or reduce your reliance on gas / diesel during a SHTF.

What you need:
- Solar panel. 80-100watts is a good starting size. It wont be "12v", it would be 16-20v, this is normal.
- 12v Battery 50Amps - 100amps. You want something that is sealed, and doesnt vent gasses.
- Regulator (go for a 20amp. Over is better, and allows for system expansion)
- 15amp (or better wiring)
- 12v light fittings. I am using 12v downlights
- a drill kit to cut the hole needed for installing downlights

Mounting the panel.
Im not doing it on the house roof. I am not good on roofs, and I do not own a proper ladder either. So instead, I'm putting it on top of the water tank. You could easily mount this on a shed, garage, etc. I am not going to bolt into the roof either.

For this setup, I cut up some aluminum angle bar. Just drill a hole through it, then drill a hole into the side of the solar panel frame. A simple nut and bolt to lock it in together.

Drilling holes:

Underneath the angle bar, I use 3m VHB double sided tape. This was recommended to me by people that have caravans and mount solar panels without drilling into the roof.
(In all honesty, I have had panels on the roof of my old house for 10 years with no mounting and it survived countless storms. However, people in hurricane areas may need to rethink the approach)

Underside of solar panel, angle bar mounted on, applying tape:

Just be aware, that you wont get the maximum power from the solar panel if it is not mounted at the correct angle. For me, my panel is almost flat, (which is really bad), but its a quick simple way to start off. Remember, something is better then nothing.

Wiring the solar panel into the house.
Some bad advice here, I did not have the correct connectors (MC4) to use for my panel, so I did this:

This works, but I have made a problem that I will fix *later*. Be sure that any connections you do, are in a sealed box or something, and then mount the box. Dont let the connector have to bear the weight of the cable, or be exposed to weather.

Here the wire goes into underground tube. You can bury it 2" deep. But really 6"-12" is better. (I did the former). It has to be in a tube and buried to protect it.

Here the wire goes in through a slightly open window (note, you need to cut a stick to length to prevent window from opening, and or use other methods to lock the window as you cannot lock a sliding window that has a cable in the way).

This is the regulator I am using (30amp capacity and it can be used in 12v or 24v systems.)

It works ok. I have not used it long enough to provide a proper recommendation.
Get a regulator that:
- can handle 20amps, (this is more then what you need to start off with).
- can protect the battery from over discharge.

The regulator that I use has 5v out. Very handy for charging your phones. At the moment I am using it to power two old phones, that are used for running mining apps.

(phones are worth scrap, cant be ethically sold, and its free power so why not mine)

I have wired up a 10amp fuse that is between the battery and the regulator. (And I have other fuses in the system).

Im using downlights, and 12v globes which are easy to get. You also need a downlight drill kit set.

From the regulator, I have wires going into a hole in the wall (no picture for this one). It took 2 people and alot of effort to get the cable from the regulator into the roof setup.
To cover the hole, you need to get a blank wall plate covering, drill a hole about the same size as the wire, poke it through and you can use silicon or something to seal around where the cable is. That was the best solution I could do.

For the light switch, I am using a wireless switch I found on ebay.

This was the easiest way for me to set it up. I DO NOT KNOW if I have have multiple of these wireless switches working together... I can update this thread when I find out.

Here is an example of a (different) wireless receiver:

Next time I am in the roof, I can take photos of how it is wired up. At the moment, I also have a fuse per light circuit.

The thing to note is that the receiver needs power for itself (cluster of 2 terminals). Then where there is a cluster of 3 terminals, in the middle is common (connect positive from battery). Then on one of the other terminals you connect positive wire to the light bulb.
Now when you press the switch it the relay connects the positive from the battery to the positive of the light bulb and it works.
Honestly, the relay really was/is the hardest bit to wire up nice and neatly.

Here is an example of the light working:

I have one downlight over each of the kids study area. So they can use it every day for study (they still use the main room light), but in a blackout situation, they can still study, or read a book (yeah right dad!) or play in their room.

Power usage calculations.
I am using 100watt solar panel and 100amp battery.
However, If you have 80watt solar panel, and maybe 3 hours of good sun, you might be getting 160 of useable watts (loss from wrong angle, etc). Clearly more sun is better, and the better the angle and the setup, the better the panels will perform.
So that gives you a max of 160w you can use a day.

If you were using a 50amp battery, you would not want to use more then 12.5 amps in one day, (so that without sun for one day the battery will not go below 50%).
12.5 amps x 12v is 150Watts.
This means that you could run 3 globes, 12w each for 4 hours. 3 x 12 x 4 = 144watts.
OR 1 x 12w globe, and 5 x 5w globes for 4 hours = 148watts.

This is just a practical example. Ideally you could have more lights throughout the house, you just need to remember to turn them off when not in use.
Also charging phones will reduce how much power you can use for lighting.

Im using 100amp battery, this lets me last longer without sun, without the battery going to flat. It also gives me more power that I can tap into using an inverter during an overnight blackout.
I actually can power my TV, laptop, microwave, fridge, etc, but of course this would be for an extremely limited amount of time. In an extended blackout, with a good setup, you could use a gen to charge the batteries and run the fridge, and then you still have power when the gen is off.

Things to note.
1. In my roof, its not an attic, there is no floor to walk on. I had to get some flooring timber, cut it into 1.5 foot wide sections to fit it through the manhole. This lets me walk in some areas, and I have smaller bits of timber that I have to move around, and lie on them, while doing work. It lets me work safely.

2. I also found out the hard way that I cannot install wiring within 2 feet of the walls, as the roof space is generally too hard / too small to get into those areas.

3. Do not work in the roof if its too hot. Do it at night, or when its cool.

4. Any wiring you do, make sure the cable is obviously different to mains power. Use the correct thingy's to hold the wiring in place. Keep it neat and tidy. You do not want to be tripping over your own wiring.

5. Stay away from mains power. Do not install 12v light too close to a mains powered light. I dont want to see people drilling into a power cable.
Before I install downlights, I go to the roof, check the area I plan to install them for any wiring or obstacles.

6. Keep insulation away from any downlights. Even 12v lights can get warm / hot, you need a 6" gap between your downlight and any insulation you have.

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Simple solar setup