Run an Arduino offgrid with high performance solar panels and solar chargers by Voltaic Systems
Yes, for three good reasons: a) Arduinos consume relatively little power during operation, b) there are lots of controls to put it to sleep when it isn't performing any useful functions and c) if the power source does run out, they restart gracefully when power is applied.
^back to topSolar Panel Charges Battery - Battery Stores and Supplies Power - Runs Arduino
We like our small solar charger kits for these applications. The V15, V50, V75, and V88 batteries charge efficiently from solar and have an "Always On" mode which keeps them on whether or not a device is drawing any power. We have more information on sizing your system below.
It depends on what mode the Arduino is in and what peripherals you have running. There are lots of forums that discuss how to put the Arduino in sleep mode so that it consumes 5mA or less. We use this as the low case, 25mA as the "running-code" case, and 300mA as constantly running peripherals case. If you're looking to run an Arduino off-grid, you will be able to run it longer with a smaller battery and panel if you can put the device in sleep mode as much as possible.
Besides the power consumption of the Arduino, the other two factors are the self-consumption of the battery (about 0.6Wh per day) and the effective output of the battery. We are measuring 12Wh and 40Wh into our load from the V15 and V50 respectively.
Arduino Runtime from V15, V50 Batteries
| # | Arduino Current Draw (mA) | Arduino Power Consumption (Watts) | Arduino Power Consumption per Day (Watt Hours) | Arduino + Battery Power Consumption Per Day (Watt Hours) | Days Runtime V15 | Days Runtime V50 |
|---|---|---|---|---|---|---|
| Arduino - Sleep | 5 | .025 | 0.6 | 1.2 | 10.1 | 33.4 |
| Arduino - Normal | 25 | .125 | 3 | 3.6 | 3.4 | 11.1 |
| Arduino - High Power | 300 | 1.5 | 36 | 36.6 | 0.3 | 1.1 |
Power generation varies based on time of year, location and panel angle. We use the JRC Photovoltaic model to predict how much power a panel will produce, on average, each day. We then assume about 85% of that is converted into stored energy in the battery. When in doubt, get the bigger panel and battery.
For more detailed solar irradiance estimates based on time of year and geographic location, see our solar modeling blog post.
Power Production into Battery per Day
| Panel Size | Watt Hours Per Day Produced by Panel | Watt Hours Per Day Stored in Battery | ||
|---|---|---|---|---|
| Texas Summer* | Minnesota Winter** | Texas Summer | Minnesota Winter | |
| 2 Watts | 9.4 | 5.3 | 8.0 | 4.5 |
| 3.5 Watts | 16.5 | 6.9 | 14.0 | 5.9 |
| 6 Watts | 28.3 | 15.9 | 24.1 | 13.5 |
*Assumes panel is angled South at 20 degrees to horizontal. **Assumes panel is angled South at 60 degrees to horizontal.
^back to topIf the V15, V50, V75 or V88 run out of power while in Always On mode, your Arduino will stop working. Once the batteries build up a bit of a buffer of power from solar (normally about 20 minutes), the battery will power up and restart your Arduino. See more on the Always On page.
^back to topThis is a running list of projects we would like to see implemented with solar and Arduinos. If you're the first person to document (blog or instructable with photos) a working project on our bounty list, we'll refund your purchase prices of panels and batteries up to $150. The project should be able to run for weeks or months at a time without interruption from humans. If you have another favorite platform other than Arduino, we're open to alternatives. Here's the list: