Polysorella
Take the Shade.
Leave the Heat.
Shade takes away the sun, but the heat stays. We are building a parasol whose canopy keeps both out.
Shade is not the same as cool
We hear it in every interview: “We were sitting in the shade and it was still too hot.” That is not imagination, it is physics.
Only the direct sunlight goes away
A parasol blocks the direct sun. The warm air and the heat radiating back from the ground and nearby walls stay. The air temperature underneath drops by only one or two degrees.
The fabric turns into a radiator
Under 800 to 1000 watts per square metre of sunlight the canopy heats up and radiates part of that heat downwards — exactly where people are sitting.
Large areas, long stays
For a short walk any parasol will do. The problem shows up on terraces, playgrounds and under event tents: a fixed area, many people, hours rather than minutes.
The difference is in the canopy
Polysorella is a parasol whose canopy keeps the heat out, not just the light. From the outside, a parasol like any other.
Throw the sunlight back
The canopy reflects a very high share of the incoming sunlight instead of turning it into heat. That way it never heats up in the first place.
Hand the heat to the sky
Whatever heat still builds up is released upwards by the fabric, at a wavelength range the atmosphere lets through. It leaves instead of coming down on you.
Nothing to operate
No power, no moving parts, no maintenance. The parasol opens and folds like any other — it just does not get hot.
We are building and measuring right now
Polysorella is a student development project at ETH Zurich. We are currently comparing several versions of the canopy on a model parasol and measuring surface temperatures with a thermal camera, each against ordinary parasol fabric as the reference.
We will publish hard numbers once the measurement series is finished. Until then nothing appears here that we have not measured — sign up below and you get the results first.
Tell us whether this makes sense to you
We are looking for people who run or use a terrace, a garden, a playground or an event space. Sign up if you want the measurement results, or if you would test a prototype later on.
We use your address only to keep you posted on this project, we do not pass it on, and you can ask us to delete it at any time. This is a student project, not a shop — there is nothing to buy yet.
Who is behind this
Five students at ETH Zurich. We are developing Polysorella as part of a semester project.
Get in touch
Questions, ideas, or do you know someone we should talk to? Write to us directly, or use the comment field in the form above.
Honest feedback helps us most. The product is still at the stage where a lot can change.