Journal ·
A Short Care Guide
A Sonnenglas doesn't ask for much — just the right little. On glass, sunshine and one USB-C port.
The good news first: a Sonnenglas keeps no maintenance calendar. It
stands outside, catches sun, glows. Three small habits keep it that
way for years.
First, the glass. It is mouth-blown recycled glass, finished by hand —
treat it like good tableware. A soft, damp cloth lifts off dust,
pollen and fingerprints; wipe dry, done. If you like, take the lid off
first and clean the two parts separately. That keeps the solar cell
free of streaks — and a clear cell means a full charge.
Second, the sun and its stand-in. From spring to autumn, the sky
handles the charging by itself. In grey weeks, the SOMO module's USB-C
port steps in: a few hours on the cable and the evening is safe. That
is not an emergency measure but part of the design — solar when the
sun is there, USB-C when it isn't.
Third, winter. You can simply let your Sonnenglas keep working:
indoors by the window it gathers light all day and moves to the table
at night. If it does go into a cupboard instead, give it a full USB-C
charge first and a top-up now and then — come spring, it starts
without a grumble.
And when, after many summers, the battery grows tired? That is the
moment the SOMO was built for: the light module swaps out, the jar
stays. Care, for us, doesn't mean preserving something. It means
keeping it in use — preferably outside, where your light comes from.