UPDATEss

After, testing the solar array, I found that the maximum voltage that can be generated was 18V (on a bright day) with the average of around 5.5 V in normal brightness. This meant we had to order a regulator that has the input voltage range between those figures. However, if you were wondering about the efficiency it was around 12%, so I may have to replace it with “better” panels at the later stages of this project.

After looking at different types, we have decided to order an isolated DC/DC converter with input range between 4.5 to 18V. It has an output voltage of 12V (as it is our grid voltage).

Isolated regulator from Tracopower

Supercapacitors vs Battery

The power from PV array, wind turbines are intermittent in nature, therefore to make it more reliable an efficient way of energy storage is necessary. This is indeed a main reason why the sustainable energy systems are taking a while to become a primary source of electricity.

Currently, batteries remain the “go to” energy storage system. Although they have higher energy density, their ability to retain energy degrades overtime due to charging/discharging cycle.

The new system that has got engineers going is to use supercapacitor as a storage mechanism. Here, the energy is stored electrostatically and does not involve chemical reactions. Therefore, it can undergo “million” charge/discharge cycle without losing its energy storing capability. It has a very high power density but its energy density is low. However, recent advances have made it possible to be used in commercial applications like electric cars.

Now for this project, I will be using supercapacitor to illustrate the energy storage. This is because while doing short demonstration later, I can quickly show that the grid stores energy during excess power and provides when power is low.

The capacitor I will be using is: Panasonic electric double layer capacitor SG of 1 Farads.