Sonnenglas in winter: Tips, tricks and frequently asked questions

Winter in the northern parts of the world means less sunshine and shorter days. Many of us don't realize how much the sunlight actually decreases during this time. But this makes a big difference, especially for solar-powered innovations such as the Sonnenglas and the SOMO. This is why our customers ask us so many questions, especially in winter.

Tips and tricks for optimal charging in winter

  1. Point the SOMO towards the sun: In winter, the sun is much lower in the sky. It is therefore important to align the solar module so that it can capture maximum sunlight.
  2. Be careful when charging behind windows: In Europe, double-insulated windows are common and can reflect up to 70% of the usable light for the Sonnenglas solar panel. Charging behind a window can therefore be very difficult, especially in winter.
  3. USB charging as an alternative: Don't worry if the sun is hiding again. You can also charge your solar module conveniently via USB and continue to enjoy the warm light.

Frequently asked questions from Sonnenglas customers

Can I leave my Sonnenglas outside all winter?

Absolutely! The Sonnenglas is robust and can be left outside without any problems. Just make sure that it is well aligned with the sun for optimum charging and that it is screwed down securely. SOMO sun modules without a glass lantern should not be left unattended.

How do I store my Sonnenglas if I don't want to use it in winter?

Ideally in a dry place. Make sure that the solar module is fully charged before you put it away. However, it is even better to simply store the Sonnenglas in a place where it is always exposed to sunlight.

Is the Sonnenglas waterproof?

Yes, the Sonnenglas is designed so that it can remain outside even in rain or snow. Don't worry about getting wet! The sealing ring makes the Sonnenglas watertight. Simply always screw it tightly shut.

Will the cold damage my Sonnenglas?

Cold doesn't affect the Sonnenglas either, but the performance of the battery drops at low temperatures. To protect the battery, you can store your Sonnenglas indoors at sub-zero temperatures.


With these tips and information, you are well equipped to make the most of your Sonnenglas or SOMO even in winter. Enjoy the warm, sun-kissed light, even when the sun is hiding. With the sun glass, you always have a piece of sunshine with you!

Author: Julia Akra-Laurien

Photos: Sonnenglas