- 1 Prepare for winter trip to Hokkaido
- 2 Items to be modified
- 3 Circuit diagram
- 4 Connect all the devices with cables, and …
- 5 Note
Prepare for winter trip to Hokkaido
Stored electric power in the solar system
105 Ah means 105 Ah × 12 V = 1260 Wh.
Assume that 70 % of stored energy can be utilized, 1260 Wh × 0.7 =882 Wh.
Multiplied by the quantity, 882 Wh × 2 = about 1700 Wh.
Required electric power in Hokkaido winter
On the other hand, expected daily electric power consumption in winter Hokkaido is
Electric blanket 30 W × 10 h = 300 Wh
Electric water boiler 440 W × 0.5 h = 220 Wh
USB charger 15,000 mAh × 3.6 V × 2 unit = 108 Wh
Therefore, roughly estimated daily electric power consumption is 628 Wh
It lasts not more than 3 days
I can say the stored electric power will last for 1700 Wh / 628 Wh = 2.7 days without sunlight.
So I decided to add 2 more batteries to the solar system to double the capacity.
Items to be modified
Number of batteries 2 => 4
Additional batteries are to be connected parallelly.
Charging and discharging batteries can be changed independently.
Add terminal block to ease future modification
I drew the diagram and parts list as detailed as possible to avoid future confusion.
Connect all the devices with cables, and …
The result is awful. Some of the cables are too short, and it is likely that sthey would be cut off soon.
So I replaced short cables with longer ones.
Like PC-case wiring, I wired as much cables as possible on the opposite side of the net to avoid entanglement.
Once wired with 5.5 SQ cables, toggle switches are almost fixed and difficult to change the position. So the route cables run should be carefully examined beforehand.
I tested the system before I left for Hokkaido, and it surely worked without problem.
Thank you for reading my article.
The original article was written and published on Jan./7/2018.