Solar for Bee research

[rwcacti]

Hi,

I need to design a solar system to power research equipment used to track honey bees in remote areas.

The system consists of a mini computer (12v) and a RFID reader (24v).
It needs to operate for 15hrs a day with max power consumption being 30watts.
This will run all year with minimum 4hours of direct sunlight per day.

What size solar panel and battery would be recommended?
Would it be best to have two 12v batteries in series then use a step down converter to get 12v for the mini computer?

I am looking for a system, which is affordable yet relatively reliable.
Any help would be much appreciated
Cheers

[Mike90250]

questions about the mini computer - have you looked at rasberry pi and such, or is it a windows only system ?

[rwcacti]

At the moment it is restricted to windows. We have experimented with raspberry pi but at this stage it is too unstable. The mini computer only consumes ~4w so its not too bad

[emartin00]

First question: Is it possible to get a 12V RFID reader? Dealing with 1 voltage will simplify things. If not, it's not a huge deal, you just need a Boost/Buck converter.
To determine how much solar you need, you can start with PVWatts to get an idea of how much power to expect throughout the year. Every location is going to be different.
For battery size, I would say you want enough capacity for about 3 days usage without solar. Again, this will vary by location. If you are in the desert where you never get clouds, then you could go less. But if you're somewhere with more overcast days, you'll want more.
As far as 12vs24V I don't think it matters much with this low power.