When we rely on solar power for our off-grid system, how can we have power when the sun isn’t shining? Let’s take a look at a very basic system with a battery.This is the third episode in the Going Off-Grid series. To start at the beginning, go to episode 9, Going Off-Grid – Introduction.

See further below for notes and additional YouTube video.

Let’s jump right into the video…

Going Off-Grid – Basic System with a Battery – Video Portion

Our New Configuration

Now we add a 12-volt deep cycle battery to our previous setup, which included a small 12-volt nominal (18.8 volt maximum) solar panel trickle charger directly connected to a 12-volt fan.


The schematic for this configuration is still very simple:

In the last episode I oversimplified the concept of “pushing” electrons by the solar panel into the battery. Now that I’ve separated the negative and positive cables, we can now see a more accurate description of the charging process: The solar panel “sucks” electrons from the positive terminal of the battery, then “pushes” them into the negative terminal of the battery.

So now we have a way to store energy for when we don’t have the sun providing it for us. However, there are some problems with this configuration. We’ll address those in our next episode.

Handy Stuff

Bulk Connectors

Here’s a handy set of small solderless bulk connectors:


When installing connectors, we will need a crimping tool to install them. Larger connectors require a tremendous amount of force, so I use a hydraulic crimper. These are relatively inexpensive. If I were doing this full time, I wouldn’t hesitate to purchase one of the more automated expensive ones, but this works great for the part time do-it-yourselfer:

For smaller connecters, this wire stripper/crimper works just fine. And it’s also useful for home wiring.

Heat Shrink & Gun

Heat shrink is a great upgrade over electrical tape. It comes in many different colors, sizes and thicknesses:

A hair dryer can be used to heat the shrink tape, but a heat gun is very effective and can be used for other types of projects:

Coming Up

How do we get regular household power from a 12-volt battery? We’ll answer that question in the next episode, Simple Inverted System.

As always, be well.

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