The Seido 1 vacuum tube is a high-performance, state-of-the-art collector that works using the Heat Pipe principle.

Inside the Seido 1 vacuum tube, there is a copper-aluminium absorber plate with a hollow tube sealed at both ends, also subjected to the vacuum and with a small amount of alcohol mixture therein. When it heats up, this mixture evaporates, rising to the upper end (the condenser) where it cools when it transfers its latent heat to the fluid in the primary circuit, thus condensing and descending again by means of gravity, and repeating the evaporation-condensation cycle.

These collectors can be used at angles ranging from 15º to 90º, and the tubes can be rotated, enabling them to be architecturally integrated into the building.