[hvalentim]

150mA consuption for a small RS fan is excessive. The one I'm using, and it can be smaller, consumes only 80mA (just measure).

Agreed. I am planning to use a 8x8cm model as this will more or less fit the circular hole I drilled in the radiation shield to house the FineOffset thing. Just found one rated at 66MA.

The SHT11 consumption is only 3.2uW (microWatt) making measurements every second, and we just do measurements every 59 seconds or 19 seconds in the case of a SHT21.

The SHT21 also seems to draw much less power.

As soon as weather permits, at night, I will go up to the roof and make real measurements of current draw from the battery during an hour period. One hour with a fan on, another hour with fan off.

That would be awesome. And a more reliable way to estimate power consumption.

On average, we have a data packet sent every 3 seconds. Wind data packets are sent every 5 seconds.

So all the arithmetic (wind speed average and so on) is done by the RX unit?

Each one may use diferent settings, my RS fan is on just when outside temp is greater than 30ºC AND wind is below 4Km/h.

That should be rare and happen in Summer only as I expected. Actually in most cases that means the power will be supplied by the Solar Cell directly.

Overall I am pretty happy with my RS, not sure I actually need the fan that much. But will apply it, just because...

Thanks for the remaining info. On the light of it I think we can drop the bar to a little under 2Ah per day. Perhaps even 1.5Ah per day.

---

Can I also suggest that if you're looking at increasing efficiency, that you err away from the "PWM" variety of solar controllers, and move to the MPPT version?

Yep. A good MPPT regulator can increase the production of an array as much as 30%. I was unaware of such an affordable model, though.

comparing this stuff to the FO approach

I think the sole remote virtue the FineOffset approach might have is annoying and aggravating users to the point they swear they will build their next weather station themselves and actually understand what the hell is going on...