Ahh very nice. I’m sure its worth it to get a standard design for all climates, and able to cope with keeping some sensors warm. Seems like the cost is going to go up dramatically though. Powering is a lot of cost and of course IP65 space is costly (for those batteries!!). I wonder if it is open sourced, or a private contract design. I use a 4.4AH LiIon, which is quite large for the Mayfly, and of course it can only charge at a max of 0.5A/hr – which means the solar panel is only about 3Watts (though easy to oversize to cope with shading) . Thanks for sharing and the references.