We have already defined the electricity consumption (=the load) and the battery size of our standalone PV system. We also know about the electrical characteristics of a solar panel. Now it’s time to determine the size of our panel. This is what we will do in this post. The key to this is the basic function of the system: The PV module has to bring enough energy to keep the system running. This means that the energy from the module must be at least the electricity consumption plus the system losses. Then the system will work. For a calculation we will take the consumption per day. Continue reading →

Now that we talked about the basics of a pv system, load, battery basics and selecting a battery it is time for the PV module that gives the system the energy it needs to work. In this post we will discuss the basics of a PV module: Electrical characteristics and how it behaves when irradiation or temperature change. The second part of this post is about testing conditions for PV modules and what the data of the module mean in real life. Continue reading →

After the basics of understanding the battery in our PV system we will now select the one that fits best to our application. First we will determine the capacity we need. Then we will have a look at different types of lead-acid batteries and which of them are well suited for the PV system. Continue reading →

In this post we will start to talk about the component that stores the energy from the PV module until it is used: the battery. We will build our system with a lead-acid battery. This post is about the basic function of the battery in our system and the electrical characteristics that are important to us. The next post will be about the different types of lead-acid batteries and how to choose the right type and size. Continue reading →

A standalone PV system begins with thinking about the load. So let’s talk about our load: The characteristics of the load determine all the components of the PV system because it must be designed to feed the load so that everything works the way we want it to.

In the first part of this article we will talk about choosing the appropriate system voltage. The second part is about how much electricity is consumed and how to optimize the system in a way that it needs less energy but still is fully functional.
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You can power your arduino from the grid, from a battery and also with solar energy. Building a standalone photovoltaic (PV) system for your application is just about choosing the right components and connecting them with a few wires. What you need is a PV module, a battery and a charge regulator to get your arduino project running offgrid. The system basically is the same as if you would build offgrid PV for e. g. a caravan, a weekend home or a small house. Here we will scale this down for our arduino needs. Continue reading →