Solar for environmental sensors

Hi, I am setting up a system of environmental sensors in different locations, outdoors in a tropical environment. They currently come able to be plugged in to the mains, but I don’t have mains - so I want to know how I can run them on solar.

specs:
DC Power Supply Requirements: Typ:5.0 Min:4.5 Max: 5.5 Volt (V)
Active Current: ≤200 Milliampere (mA)
Peak Current: ≤600 Milliampere (mA)

What would I need and what is the unit cost?
I want a battery as well as I want them to be able to run continuously day and night (and in bad weather as far as possible)

Hi Cynthia,

I recommend this panel or larger:
https://core-electronics.com.au/solar-panel-9w.html

This charger:
https://core-electronics.com.au/usb-dc-solar-lithium-ion-polymer-charger-v2.html

This Regulator:
https://core-electronics.com.au/pololu-adjustable-4-12v-step-up-step-down-voltage-regulator-s18v20alv.html

And this battery:
https://core-electronics.com.au/polymer-lithium-ion-battery-6000mah.html

That’s a pretty large spread on the current needs. It’s hard to know what the average draw will be. So this setup is likely overpowered. I assumed an average current of 400mA, and the regulator only works at 80-90% efficiency so you will lose a bit there.

Let me know if you have any further questions and good luck on your project!

Hi,
They are all the same unit, that range is just the data from their website (https://www.purpleair.com/sensors)

There is a similar Australian product that already includes solar, but it lacks some of the other features (and they want $15 K to tell me how to set it up).

We want to put them all over the Pacific Islands.
I will use your costs in the proposal and hopefully we we will be successful

Thanks,

Cynthia

Cynthia,

Happy to help! Even if this setup is a little overpowered that might be necessary to operate effectively with overcast skies and occasionally unideal solar weather. We will tell you how to set up this stuff for free! :grinning:

If you are going to be setting up sensors everywhere, we should be talking about reading them remotely! I took a look at the PurpleAir sensor. It looks like it goes for about AUD $350, and has wifi capability or needs to be checked physically to get the data.

You could use this sensor:
https://core-electronics.com.au/pm2-5-sensor-module-laser-sensing.html

and this controller:
https://core-electronics.com.au/pycom-lopy4.html

with this shield:
https://core-electronics.com.au/pycom-pysense-41969.html

and antenna:
https://core-electronics.com.au/pycom-lora-sigfox-antenna-kit.html

and build your own sensor for about $240 that would have LoRaWAN capability. You could send your data wirelessly up to 40km with this system! The PurpleAir needs to be checked manually or near Wifi, and I think that might be very limiting.

Anyway, good luck with your project, it sounds very cool. I’d love to know on how it progresses!