Solar power basics

Before getting a solar panel for our van I didn’t have very much experience with solar energy. Luckily my boyfriend has both theoretical and practical experience with installing solar panels, and he has explained some of the basics to me. So I thought I would write two posts about the installation and use of solar panels for our Ford Transit Connect.  This first post will explain some of the basics that are needed to run a solar system. (Of course, any errors in this post are my own!) The next post will be go through the specific steps we took to install the panel onto the roof rack of our van. 

What are the components you need to convert sunlight into electricity that will power your electronics?  Obviously, the first thing you need if you want to generate solar energy is a panel. For $160, we were able to find a panel was made in Eugene, Oregon that can generate up to 100 watts. While we only have space for one 100 watt panel on our roof, these panels can also be linked together to generate more energy.  The solar panel we chose came with pre-installed junction box and a pair of 31 inch cables with MC4 connectors. These cables easily join to anything with a MC4 connector. 

But a solar panel is definitely not the only thing you need if you want to use the sun to power your devices. A solar panel only produces electricity when it is sunny, so you need a battery to store electricity when it is not sunny. You also need something to control the flow of electricity from the solar panel to the battery. This is called a charge controller.

The charge controller maintains a steady flow of electricity to the batteries and prevents them from overcharging. Not only does overcharging reduce battery performance and lifespan, it also poses a safety risk. Charge controllers also regulate the energy to prevent it from flowing out of the battery back into the panel when it is not sunny.

Solar panels produce direct current (DC) power, and batteries store DC power. However, household electronics such as lights, laptops, radios, refrigerators, all run on alternating current (AC) power.  Therefore, it is necessary to convert the DC power stored in a battery into AC power that can be used by your electronics. An inverter changes DC power into AC power.

Therefore, the major components you need to convert sunlight into usable electricity are (1) a solar panel; (2) a battery; (3) a charge controller; and (4) an inverter.

How does a solar portable power system work? A portable power system combines the battery, the charge controller, and the inverter into one box. This makes the easier to use as it eliminates most of the electrical work and wiring needed to safely install solar panels. Additionally, as all of the components are in one box they take up less space. Portable power systems are also sometimes called solar generators.

What solar portable power system did you choose? We went with the UPG Adventure Power 800 Watt since it had the physical profile and power output we were looking for. The model we chose can be recharged from a household AC energy source in addition to the DC solar panel – which is a good feature that allows for charging on cloudy days.  Goal Zero also has a wide range of products and I would also recommend this company to someone who is interested in entry level solar.

What can you power with a 800 watt portable power system? The system can provide 5 charges to a laptop, 65 charges to a mobile phone, provide 8 hours of light to a small lamp.  In addition to a standard plug, the system also has a USB port.

How long does it take for a 100 watt solar panel to charge the 800 watt portable power system? It takes about 10 hours to completely charge the power system from the solar panel under optimal sun conditions. It takes about 14 hours to completely charge the power system from a household AC energy source.

What are the drawbacks of the portable power system? The main drawback of our solar portable power system is that it is limited in the amount of power the battery can store. The battery we have is too small to power a refrigerator, for example. Our van is small though, and we don’t really have room for a refrigerator, so that wasn’t a deal breaker for us. If you want a bigger battery that can power more electrical devices, then you would need to purchase and install the inverter, charge controller, and the battery separately. There are some great sites out there that explain the process.

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