Thermal Evacuated Tube

Facts
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About the project
Evacuated solar collector tubes for solar dishes (focal tubes) absorb solar energy and transfer the heat to a medium, such as oil, that is circulated in the pipes and stored in a buffer tank.
A hotspot tube consists of one or two glass tubes made of extremely strong borosilicate glass. The outer tube is transparent and allows sunlight to pass through with minimal reflection. The inner tube is coated with an aluminium nitride (Al-N / Al) coating or made of steel SUS 316 or 420. This selective surface is excellent for absorbing solar radiation with minimal loss of reflection.
Challenge
The purpose of the collaboration between ATE Denmark and DTU is to improve ATE Denmark’s existing technology for hotspots by achieving better efficiency. Furthermore, the goal of the project is to ensure that production is placed at ATE Denmark in Slagelse.
Solution idea
- Coating of focal tubes with carbon nanotubes
- Mixing of carbon nanotubes for the heating medium
Project deliverables
Test and report as well as improvement suggestions.
This project is financed by Energy Cluster Denmark’s Clean Tech Innovation (CTI) support programme. It offers three years of support to allow small- and medium-sized businesses to collaboratively develop innovative electronic products focused on energy optimisation. The CTI project is supported by the European Regional Development Fund.
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