Enviro+ on batteries

Discussion
#1

Hello,

I’d like to run my Enviro+ Pi Zero outside on 18650 lithium batteries with a solar charger.
I’m successfully sending the data over MQTT to influxdb and displaying on Grafana.

I realise RasPi’s don’t have a deep sleep mode, so are there any commands I could use to disable things such as the lcd panel on the front of the Enviro+ or the HDMI output from the Zero etc. to save power?

Thanks
Ian

#2

You might be able to turn the backlight on the LCD off. The pinout shows its wired to GPIO 12.
Enviro Plus at Raspberry Pi GPIO Pinout

I have this in my crib notes for my 0.96 160x80 LCD breakout. Haven’t tried it yet. I know if I ground the BL pin the backlight turns off, and when I remove the ground it turns on again.

disp.set_backlight(0)
After doing something like this to initialise it :-)

# Create LCD instance
disp = ST7735.ST7735(
  port=0,
  cs=1,
  dc=9,
  backlight=12,
  spi_speed_hz=10000000
)

# Initialize display
disp.begin()
#3

Ok thanks I’ll give it a try.

#4

I guess another option is to just edit out the code that displays the info. Assuming you don’t ever plan on using the onboard display.
And another option is to swap the enviro for the individual sensor breakouts.
I’m running the weather and light Enviro Example on an equivalent breakout garden setup.
0.96 SPI LCD, BME280, LTR-559 and RV3028.
What data are you collecting, maybe all you need is a BME280?

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#5

Thanks again, I’ll think I’ll go the “edit out the code that displays the info” route as I’m quite interested in the PPM, lux, and gas values as opposed to just having a BME280.

Attached is my Grafana dashboard not much happening at the moment as there hasn’t been much sun and the batteries are down.

Screenshot 2021-01-04 at 19.49.42
Screenshot 2021-01-04 at 19.49.424950×2290 642 KB

#6

I’ve noticed that even with my backlight pins grounded, and the backlights off, there is still a low level of light still visible. I can just barley make out the graphs in a pitch black room. In normal light they look totally off.
Not even initializing the screen is likely the way to go.

#7

Have you done any calculations to determine the solar panel size?

Andreas Spiess: #142 Solar Power for the ESP8266, Arduino, etc. (YouTube) goes through a worked example.