Many do not realize this – building a solar panel is different from building a solar power system. A solar panel is only a part of a solar power system, whereas the solar power system consists of not only a solar panel, but also an inverter, charge controller and battery banks.

For a complete solar power system, the above mentioned three items are essential. Let us look at each of them:

1. CHARGE CONTROLLER

The reason you want a Charge Controller is to prevent a sudden surge in the output of your solar power system, as the surge can damage the electrical appliances connected to your system.

Most of what a household needs is only a basic Charge Controller. You can choose to save money, until you decided to get an advanced one for their more professional features.

When you choose a Charge Controller, get one whose specification fits the output current of your solar power system. Take note that some salesperson will recommend you to hook up two or more affordable Charge Controllers instead of getting a large one for your system, saying this will save you cost. However, usually a large Charge Controller performs better than a few small ones cascaded together.

2. BATTERIES

The solar power system does not generate energy at night, and does not perform well during winter time or rainy days. This is why we need batteries to store up the charges generated from the system for use in these conditions.

You need to perform some calculation before you specify the size of batteries you need. Besides, you have to think about how you want to use the energy you store up: Do you want it to get you through rainy days only? Do you want it to provide you electricity overnight only? Or do you want to have reserved energy for three days to a week?

Ideally you should choose batteries that are very large so that it can store much more energy than what you need. However, we need to consider the cost and the physical size of the batteries. So it is not realistic to get oversized batteries. Moreover, if your house is still tied to the grid, you only need to get a small set of batteries to get you by cloudy or rainy days.

3. INVERTER

Most of the electrical appliances in our house take in Alternating Current (AC) to function. The output of a solar power system, however, is Direct Current (DC). To allow the electrical appliances to draw energy from the solar power system, an inverter is used to convert the AC into DC.

Choosing an inverter for your system is straightforward. You only have to select one according to the demands of the AC side of the inverter. You have to make sure that the inverter is able to fulfill the needs of the loads (the electrical appliances) in your house. Also, remember to add in a reasonable buffer in case your load increases.

Most DIYers do not have sufficient professional technical knowledge to decide the correct Charge Controller, batteries and Inverter to use, and how to hook them up to form the complete solar power system. This is one of the times when it is wise to seek professional help, because it can not only save us from guess work, but also prevent us from wasting money and time due to getting wrong parts for our solar power system.

An engineer by profession, through extensive personal research and exchanging information with the online community, Harvey Normad made himself an expert in DIY solar power system. Together with two other like-minded friends, Harvey set up a website on this topic. They are dedicated in posting their latest findings and insights on homemade solar energy system. Rich information, including steps to set up DIY solar panels, are shared. Visit the site for more tips on DIY Solar Panel.