Charging the Panel!

Last week Siena was on spring break and that means I had some free time during the day to get outside and see what my solar panel can do for the battery. I was lucky enough to get a few mostly sunny days that allowed me to get some great data. The first day that I was able to get outside and charge the battery was a beautiful day. I was ready to go at 10:00 AM with a fully drained battery and a solar panel that was ready to catch some sunlight. I took measurements of battery level, current, and voltage every half hour until the sun set while taking note of the cloud cover. When the solar panel was fully exposed to sunlight the measurements fluctuated between 2-3 Amps and 12-13 Volts. In the first four hours of charging when the sunlight was direct the battery charged to somewhere in the range of 40-60%. I could not get an exact reading because the charge controller uses five bars to display the battery level and therefore only provides a range for the battery level. After first four hours the cloud cover significantly increased and the panel stopped getting direct sunlight. As you would expect the current being produced by the panel dropped significantly to around .5 Amps and then worked its way down to 0 as the sun continued to set. Although the battery did not fully charge this first day provided a great deal of high quality data that I can work with.

The following two days provided similar data but I made sure to get out earlier in the morning to get more hours of sunlight. The extra sunlight allowed me to overcome the 60% barrier that I faced on the first day. Although I never surpassed 80% I am still considering this a victory.

In the coming week I am planning to look into a set up using raspberry pi that will use a camera so a user would be able to check the charge on the battery without constantly going outside to check manually. I also plan to build a set up that holds the solar panel facing the sun while doubling as a protective cover for the other pieces.

I Need the Sun

So this week saw some nice progress and some big disappointments. I found a fairly quick way to drain my battery which is nice because I'll need to drain it quickly so I can recharge it. I used it to power a mini fridge and that did the trick over night. I was ready to finally charge the battery back up using the solar panel but when I took everything outside I found that when the cloud cover is too high I cant get any current from the solar panel. So, me and the Sun are having some scheduling conflicts and I haven't been able to get the battery to charge yet. Hopefully this week will bring some sunnier days that give me an opportunity to get outside and charge this battery. I want to find out how long the battery takes to charge using this panel, that's my next goal.

...Finally!

This week I received the final piece to my puzzle: the cables to connect my solar panel to the charge controller. I was very excited to finally put all of my pieces together into one circuit. I got to test the whole thing for a little bit this week but I have only been able to use a lamp with the solar panel. I'm hoping to have some nice weather this week so I can take everything outside and get some real sunlight on the panel.

Putting all of the pieces together is a very big step for me and this project. Now I know that I can use the panel to successfully charge the battery. I'll need to drain the battery soon so I can start to figure out how long my panel will take to charge the 12 V battery and then work on ways to make that time faster. That is my goal for this coming week. If I can make maximize the efficiency of my circuit then life will be easier for those who may eventually use this as a source of power.

Testing the Panel and Starting Construction

The panel that I will be using to charge my battery is a Suaoki 50W Semi Flexible Solar Module. 

Suaoki 50W Semi Flexible Solar Module

This panel is rated for 17.6 Volts and 2.84 Amps. Even in the extremely cloudy and gray January sky the panel is still outputting over 16 volts when it is directly facing the sky. This is a good thing because it shows that even when the Sun is not shining bright in the sky the panel will still be producing a current. The current that the panel was producing was about .14 mA when it was directly facing the sun. This is enough current to charge the battery when we get there.

Construction:

This past week I have connected the battery and the inverter to the charge controller. Since the battery is already charged I was able to power the inverter and start charging some devices like my phone and laptop. Now we know that this part of the system works. The next step is to add the solar panel and see if we can the battery to charge. The final pieces have been ordered and should be here by the end of the week. Once they come in I will be connecting the panel and starting the charge the battery (hopefully). 

New panel!

Since last week I have continued my research into how all of the pieces to my project work. The more I can understand about how they all work, the better I can make my circuit. I'm hoping to be able to make the most efficient and effective circuit possible.
We have recently gotten a new solar panel which I hope to have connected this coming week. Once that is connected we can start to charge the battery! Before anything gets connected I will need to do some testing on the panel. I will testing the voltage and current that it is producing.
By next week I am hoping to have done enough testing to start building and get everything connected. Once we have everything hooked up the next stop is testing and making sure the battery is getting charged.

My Goal!

Working with Dr. McColgan, I am attempting to charge a battery using a Solar Panel. In Bolivia, schools have a hard time staying open because of unreliable power. Using the panels as a current source, I will look into ways that use batteries as a place to store energy. Hopefully I will be able to find a way to store enough energy to keep the Bolivian schools up and running during these power outages.