Nano solar power

Hi,

I'm looking to create a solar power shield for the nano. The plan would be to have a nano with female headers soldered to it, and then a custom shield which will be the solar charge controller with a small LiPo / Li-Ion battery and a solar panel the size of the nano. It will all need to be compact.

Would such a small solar panel be enough to charge the battery AND power the nano for about a minute every hour to take some sensor readings, then go to sleep the rest of the time?

Thanks

A better approach would be to use the Pro Mini, and remove the LEDs and voltage regulator (swipe them off with a solder pencil). That way you avoid having to power the USB connection.

Power saving tutorial here.

Some great ideas in this article describing a solar powered Arduino using a supercap instead of a battery.

Thanks! I will take a look at the links. I know I can power the 5V pin directly to power the nano. Does this still power up the USB? I'd prefer not to have to remove components from the nano if possible, and I already have 10 nano's, so would rather stick to nano.

Yes, powering with 5V powers the FT232 USB adapter. You could cut the trace to the adapter, but then you can't use it.

It probably wouldn't matter too much, I could cut it if it becomes a problem but really it's only going to be powered on for 10 seconds or less during daylight hours. I'll use an external timer and a relay.

If you used an attiny84 or 85 you,ll be using way less power and could probably even just stay on

NeilSawhney: If you used an attiny84 or 85 you,ll be using way less power and could probably even just stay on

That prompted me to look at the datasheets and at 8mHz and 3.3v the Atmega 328 seems not to draw any more current than the Attiny 84 - both require about 3 mA in active mode. The Attiny1634 seems to require a bit less, but it is only available in SOIC form so it required delicacy with the soldering iron :)

...R

jremington:
A better approach would be to use the Pro Mini, and remove the LEDs and voltage regulator (swipe them off with a solder pencil). That way you avoid having to power the USB connection.

Power saving tutorial here.

Some great ideas in this article describing a solar powered Arduino using a supercap instead of a battery.

why remove the VR from the proMini

why remove the VR from the proMini

You can then power the Pro Mini through the +5V output without current leakage through the voltage regulator, or possibly even damaging it.

JoeyJoe: Hi,

I'm looking to create a solar power shield for the nano. The plan would be to have a nano with female headers soldered to it, and then a custom shield which will be the solar charge controller with a small LiPo / Li-Ion battery and [u]a solar panel the size of the nano.[/u] It will all need to be compact.

Would such a small solar panel be enough to charge the battery AND power the nano for about a minute every hour to take some sensor readings, then go to sleep the rest of the time?

Thanks

Check how much energy and at what voltage a PV of that size will be, why does it have to be compact? How are you storing, displaying or transmitting the data? Tom... :)

Check how much energy and at what voltage a PV of that size will be

It is entirely feasible. I used two Panasonic BP-242221 cells connected in series to recreate a minimal version of Nick Gammon's solar powered Arduino project.

The two cell panel measures 5 cm x 2 cm and puts out 28 mW @ 4.2 V in full sun.

That is considerably more than enough to charge a 0.47 F supercap, run a bare bones Arduino, a sensor and have a 10 mW 433 MHz transmitter transmit data for 1 second every minute, 24 hours/day. That is, if the sun shines every day.

TomGeorge: Check how much energy and at what voltage a PV of that size will be, why does it have to be compact? How are you storing, displaying or transmitting the data? Tom... :)

I like the idea of making a miniature weather station, but also wanted to get the PCB's manufactured eventually.

Hi,

JoeyJoe: I like the idea of making a miniature weather station, but also wanted to get the PCB's manufactured eventually.

How are you dispersing the data? Wires, WiFi, NRF24 ?? ?? ?? ? Tom... :)