Thermal Energy-related Bibliography

NightHawkInLight. 2016. How To Make Parabolic Mirrors From Space Blankets. Video. Retrieved from

In this video, we see how an air-tight frame and over-pressure can be used to distort a 'space blanket' into a parabolic(-like) shape. It goes on to show how fibreglass, when applied while the film is under pressure, together with a cylindrical 'former' can be used to help retain this shape once it is removed from the frame.

While interesting, the costs of the fibreglass, resin and the cylindrical former likely add quite significantly to the cost of the reflective film. Perhaps this can be alleviated by bonding the film to an acetate backing sheet and distorting the resulting material under heat, as per Robert Murray-Smith (2022).

Sergiy Yurko. 2022. Its efficiency? The world's cheapest solar heater of Parabolic Dish type. Video. Retrieved from

In this video, we see how stiff(ish) wires placed on the front side of the concentrator can be used to tension 'space blankets' into a concave reflector. This has the advantage of not requiring, e.g., fibreglass to retain the reflector's shape post-forming, however it does seem to make it harder to achieve the more ideal parabolic shape; this could, perhaps, be ameliorated by, e.g., cutting threads into the ends of the wires and using nuts and washers to make it easier to fine-tune the tension of each wire post-installation. The video also shows the use of a simple mechanism that can be used to keep the target at the reflector's focus, even as the sun tracks through the sky.

Although the measurement methodology is not explained, this video also includes results which suggest a collection / concentration efficiency of ~500W/sqm.

Sergiy Yurko. 2022. This solar energy innovation is 10 times cheaper than analogues: solar electricity 24 hours a day. Video. Retrieved from

Robert Murray-Smith. 2022. 1384 How To Make Lenses of any Size or Focal Length Easily and Cheaply. Video. Retrieved from

In this video, a technique is shown that can be used form parabolic(-like) lens shapes out of polyethylene terephthalate (PET/PETE) sheeting using an air-tight former, heat to soften the plastic, and over- or under-pressure to create the actual deformations.

Pairs of the resulting sheeting can be joined and filled with water to create actual lenses (where their curvature / focal-length can be controlled by adjusting the pressure of the partial-vacuum used during the forming process), however, it's also possible that, if the PETE sheeting can be bonded to 'space blankets' using a flexible adhesive, the resulting laminate could be used to vacuum form parabolic reflectors for use in solar-thermal concentrators without the need for the fibreglass backing or wire-grid tensioning used in the above videos.

From, “A heat pipe is a heat-transfer device that employs phase transition to transfer heat between two solid interfaces.

“At the hot interface of a heat pipe, a volatile liquid in contact with a thermally conductive solid surface turns into a vapor by absorbing heat from that surface. The vapor then travels along the heat pipe to the cold interface and condenses back into a liquid, releasing the latent heat. The liquid then returns to the hot interface through either capillary action, centrifugal force, or gravity and the cycle repeats.

“Due to the very high heat transfer coefficients for boiling and condensation, heat pipes are highly effective thermal conductors. The effective thermal conductivity varies with heat pipe length, and can approach 100 kW/(m⋅K) for long heat pipes, in comparison with approximately 0.4 kW/(m⋅K) for copper.”

Robert Murray-Smith. 2015. How To Make A Heat Pipe (or solar heat collector). Video. Retrieved from

Robert Murray-Smith. 2015. Improved Heat Pipe: Over 95% Efficient. Video. Retrieved from

In these videos, the principles and applications of heat pipes (including their use in solar water heaters) are discussed, and the construction of a simple heat pipe made out of water and copper tubing and end-caps is documented.

Robert Murray-Smith. 2015. Graphene Based Thermal and Solar Fluid. Video. Retrieved from

From the video's description, “A useful solution of graphene for improving absorption of light and transfer of heat [is presented]. It could well improve the efficiency of solar panels and cooling systems.”

  • Last modified: 2022-03-14 10:31
  • by Peter