Raspberry Pi runs with solar power – Part 3
After some theory about the Raspberry Pi and solar power and my calculation about needed solar power and costs, its time to present you my solution. The idea was to get the best performance for a good and cheap price. You may think that it can be cheaper, true, but you should also consider quality. My aim was to run my Raspberry Pi as long as possible without breaks only with solar power. For this I used to following hardware:
Solar panel
For my solar panel, I used EasyAcc solar loading station, which had the best cost-benefit ratio. It is also small and transportable. This solar panel has a USB plug to connect and delivers at direct sunlight enough energy to run my Raspberry Pi. The solar cells are very stable and weather resistant, so it is no problem if it rains. The solar panel can be packed easily.
Support battery
I’m using this EasyAcc 10000mAh power bank from the same manufacturer as a support battery. For me it was important that this power bank has enough battery charge to run my Pi and it should also be able to charge my smart phone or iPad. 10Ah are enough to run a Raspberry Pi more than a day only with this battery.
This power bank also displays the current state of charge which is important. If your solar panel delivers too less energy to charge this battery, you have to use your home power socket to load it. Otherwise your Pi may stop working during the night. A power adapter is not included, but you can use some micro USB adapter.
Mobility
I’m happy with my products. I can use the battery for many different things. I can use it with my Raspberry Pi, smart phone or other gadgets. The power bank turns my Raspberry Pi into a portable computer. The solar panel helps me to use my Raspberry Pi without battery in sunlight or to charge my power bank. Now I’m very flexible with my Pi and do not need power sockets all the time.
Test
In summer everything works perfect. There is enough sunlight to run a Raspberry Pi. In winter it is a bit harder, there are only some sunny days and you have to use the power bank.
How did you connect the Solar panel & the Battery pack together? Or were you simply connected them separately?
My battery pack has 2 USB out plugs to connect 2 gadgets at the same time. It also has a micro USB in to charge it. So it is possible to run your Pi with it and load it with a solar panel.
Take care about the fact that many USB batteries cannot provide power AND reload at same time.
For example I tested a few Anker up to 8000mAh and if I connect external power to reload the battery then it stop sending current to connected USB device.
Also all external USB batteries never give you real mAh written on the box, this value is the internal 3.7v Li-Io batteries capacity (they are all 3.7V), so when you reload the battery you plugin a 5V external USB power this is lowered before getting into Li-Io battery, but on the contrary when you power a connected USB device then this 3.7V „internal“ current must be elevated to 5V again so you loose about 30% of capacity because of this conertion.
Thank you for that. You are rigth. 8000mAh are never really 8000mAh that can be used.
You may cumulate the solar cells or buy a more powerfull, I found two interesting on Amazon :
http://www.amazon.fr/RAVPower-chargeur-portable-Technology-smartphone/dp/B00SSZAJUK/ref=cm_cd_al_qh_dp_i
http://www.amazon.fr/Anker%C2%AE-Chargeur-Solaire-Portable-Double/dp/B00IPBH5AO/ref=pd_sim_23_8
But if you cumulate two of yours then you get same power but cheaper price, but I don’t know about quality…
By the way I received no notification for your previous answer, do you blog send reply notifications ?
Also for the „worst situation“ why did you choose 12V soler cells + battery and not 6V, any special reason ?