Development of Bifunctional Photovoltaic Modules for
Building Integration BIMODE
A cost shared collaborative R&D Contract between BP Solar,
KHM, Bayer AG, Ove Arup, AIOU, IES and TFM, funded in part by DG XII of the European Commission under contract
JOR3 CT97 0175
Enerbuild Number 22
Co-ordinator: Dr T M Bruton, BP Solar
Presenter : Dr MH Patterson, BP Solar

BIMODE:
A project to combine the best of both worlds
Environmentally friendly
Photovoltaic cells
Available in a range of sizes,shapes and colours
Artists and architects
Skilled in enhancing the visual environment
Through the use of form,
Shape and colour

BIMODE Project Organisation:
Project Co-ordination
BP Solar
Task 1
Aesthetic Design
KHM
Task 2
Supply of Multicrystalline wafers
Bayer
Task 3
Solar Cell Processing
BP Solar
Task 4
Modelling of Solar Cell
Arrays
IES
Task 5
Prototype fabrication
TFM

BIMODE
> Objective
>To develop a range of prototype modules with solar cells of varying shape, texture size and colour which have high visual and aesthetic appeal and function as electricity generator in building integration.
> Specifically four prototypes will be manufactured one of which will have an 8% module efficiency

Cube Module

Examples of triangular cell and module designs.

Triangular Module

Possible Renovation of St. Gertrude Church in Cologne using the triangular prototype.

Picture of Bruno Taut’s glass pavilion with triangular modules

Striped Module

Striped module design and application of the striped module to the Mannesmann multi storey car park.

Prototype design of hexagonal module with sinusoidal bus bar design.
•200 hexagonal cells
•Sinusoidal busbars
•Cells >10% efficiency

Prototype Module Results
Module
“Triangular”
“Striped”
“Hexagonal”
“Cube (dark blue)”
“Cube (steel blue)”
“Cube (titanium)”
2.72
2.67
Isc
[A]
1.49
6.05
2.98
3.04
Voc
[V]
14.55
17.37
46.07
21.95
FF
0.62
0.63
0.62
0.78
Pmax
[W]
13.4
66.1
86.0
52.1
21.77
21.94
0.79
0.77
46.6
45.2
Module-
Eff [%]
6.3
7.6
6.7
12.1
10.8
10.5

Deliverables
>
Report on different casting conditions to produce large and small grain multi-crystalline silicon
>
Report on modelling of cell interconnection to allow minimum mismatch when cells of different size and colour are interconnected
>
Design and demonstration of four prototypes with cells of different shape and colour
>
A seminar ( Cologne 1999) illustrating the aesthetic possibilities to architects and designers.
>
Design of application of BIMODE modules to actual buildings.

Conclusions
> The project is complete and has demonstrated that
PV modules can be viewed as works of art and still generate useful electrical power.
> The existence of BIMODE modules has stimulated interest in the use of PV integrated in buildings as a means of enhancing the building appearance and adding value through its aesthetic appeal.