This document describes a new solar roof tile system invented by Frédéric Marçais that incorporates a water tube to capture solar thermal energy. The system uses standard clay roof tiles with a modified profile that allows a water tube to make direct contact for heat transfer. Prototypes were tested by a university and found to have efficiencies between 7-20%, with the potential to reach 30% after further optimization. The system provides a low-cost way to harvest solar energy using local materials and blends seamlessly with traditional roof aesthetics for both new buildings and renovation projects.

1. Solar Roofing Tiles
with incorporated
water tube
Thermal recovery of solar radiation.

2. Examples of coverage in tiles. This is
the Langres Cathedral located in
France.

3. The Cathedral Saint Stéphane , in
Vienna, Austria.

4. Cover of a typical house in the
Mediterranean country, with channel
tiles.

5. These roofs are part of our cultural and
historical heritage. They are aesthetic and
well protected by a sustainable and
secular component, clay tile.
Different collector systems are now able
to recover thermal energy radiated by the
Sun.
They are not very aesthetic, and their
manufacturing need expensive
materials, a lot of time and energy.

6. Main of them are tubular collectors
and flat plate solar collectors.

7. An other solution can work preserving
aesthetics of existing buildings.
It is a very low cost system, using clay
tiles as thermal collector.

8. My target was captation of the
heat existing between tile and
roof without any visible system

9. The system I have invented can work
with all standard pattern tiles

10. The first prototype mold I have
engineered

11. It is a very low cost system, using clay
tiles as thermal collector.

12. Molding clay in the first mold i have
done

13. Removal of the first prototype tile

14. New heat recovering profile fitted
under a mechanical tile

15. Now, prototype mold can be created

16. Water Tile
tube Grooves
Water is heated by contact with the specific
profile of the tile, and the heat staying
between tile and insulation of the roof.

17. A patent has been given (in year 2010) to Frédéric Marçais

18. Install the roof tiles…
Externally, the roof looks like an ordinary tiles cover.

19. Recover Energy.
Once the roof completed, it is impossible to see if a heat recovery system
is working under the tiles.

20. Hydraulic heat collector network (3) is laying under the
tile.
Tiles are laid upon the tube (3) for heat recovery. They
are fitted on a specific base (7).

21. Contact with the tile is
sometimes uneasy…
But we’ll see about that
later…
Contact between the tile and the
tube

22. Craft achievement of the
prototype.
1 M²

23. 2010 Salon international des
inventions de Genève…

24. …Organised with agreement of theWorld
Intellectual Property Organization (wipo)

25. Gold medal for Frédéric Marçais

26. This is gold médal

27. Experimental
Facilities
To evaluate the performance of the
system, a prototype installation of one
square meter was completed.

28. Overview of the laboratory of
Brétigny-sur-Orge.

29. Hydraulic facilities, thermostatic
water tanks

30. Thermal performance tests were
conducted by the University of Évry
for several months.

31. Main purpose was evaluation of the
performance of this tile modified for
heat recovery.
Installation can also evaluate
performance and behaviour changes
in variable environment
(sun, heat, water flow, etc)

32. The simulation device for thermal
radiation.

33. Testing facilities created and used by
Professor Ayoob and Michael
Germant during the campaign.

34. rendement
0.600
0.500
0.400
0.300 740W/m²
0.200
0.100
T entrée (°C)
0.000
0 5 10 15 20 25 30
rendement
0.600
0.500
0.400
0.300
370 W/m²
0.200
0.100
T entrée (°C)
0.000
0 5 10 15 20 25 30
The one square meter patented roof tiles is
tested according to different levels of solar
radiation. Here: 370 W/M² and 740 W/M²

35. rendement
0.600
0.500
0.400
0.300 qm=1 L/ minute
0.200
0.100
T entrée (°C)
0.000
0 5 10 15 20 25 30
rendement
0.600
0.500
0.400
0.300 qm= 3 L/minute
0.200
0.100
T entrée (°C)
0.000
0 5 10 15 20 25 30
A lot of levels of solar flux and flow were tested.
Changes flow are carried out inside the collector tube. Rate
of one liter per minute (up) and three liter per minute
(down)

36. Behavior of tile panel was
tested, working with different solar
insulation, water flow and water
temperature intake.
The current system of Solar tiles is
cheap, easy to produce locally, and
simple to use.
Efficiency of the prototype tile was
measured around 7-20 %, with
possibilities to reach 30% after
optimization.

37. Rendement
0.250
Rendement Linear (Rendement)
0.200
0.150
0.100
0.050
0.000
0.0000 0.0010 0.0020 0.0030 0.0040 0.0050 0.0060 0.0070 0.0080 0.0090 0.0100
(T*-Ta)/i (K*m²/W)
Presentation of the performance datas of
the system.

38. This view shows theorical solar yield curves of the
international chart F ((Tm-Text) /i) = r.
The patented tiles are compared with conventional
solar collectors .
Efficiency of the patented tiles (blue points) can be
easily improved to approximately 30 %

39. Tiles have a large thermal inertia.
The curve shows evolution of temperature changes
over time.
Tiles will provide heat after sunset.

40. The system help easily heating building
installation in springtime, summer and
autumn.
It is possible to fit - at very low cost - a
very large surface of the roof.
The materials used are sustainable
, with a very long life cycle.
Recycling is cheap and easy.

41. Example of use: hot water
preheater

42. Prospect
development
Several modifications are possible to
improve the recovery system.

43. The first way is to improve
contact between tile and
heat collector network

44. Look at the
operation more
closely.
I have developed a new support to facilitate tile’s
installation, by quick stapling on the patented support

45. T1 Left : The support (9)differs when the
roofer push down the tile (3).
T2 Right : The support immobilizes the tile.

46. This support is multi-
fonctionnal and
upgrade the system
with many additional
benefits.
Support significantly improves the contact existing between tile and
water heated network. Heat transfer become better.

47. Support is also designed to work
under channel tiles.

48. It facilitates the roofer’s setting work and
save time.
1) New patented
support
2)Tube
3) Tile
9) Arm
11) Cavity
12) Hook
Big advantage : it allows roofer to set all
the tiles without risk of mistake, making
them highly resistant to winds and storms.

49. A good way to increase performance of
the system consists in upgrading thermal
insulation (between tile and roof)
Performance improvements are possible
by modifying shape, position and size of
the tube under the tile.
Research is underway in preparation for
industrialization.

50. Design optimisation
Form Position Size

51. Conclusion : it’s the cheapest way to
produce hot water to heat building or
domestic use.
This system is very easy to
install, cheap, and offers smart look to
new or old buildings.
Materials used are available
everywhere, recyclable, with a very long
life cycle (minimum 30 years).
This system will complement existing
thermal solar solutions, discovering a
new original and sustainable way.

52. Solar Roofing Tiles
with incorporated
water tube
Thanks for your attention.
Obrigado por sua atenção. Frédéric Marçais
Merci pour votre attention .