Sunreign Reference: BIPV Building Integrated Photovoltaics

BIPV Building Integrated Photovoltaics

BIPV or custom solar panels often include glass. There are several options to make panels based on the materials used in regular panels.

EVA is used to cushion the cells, so above and below. It is a thermoplastic material that was once proposed because it is dirt cheap. For solar applications however the price is about 14 Euro per m2. It requires a melting process.

Epoxy Epoxy is used to encapsulate cells. It can remain clear and should be a usefull candidate. It is not advertised as such. One reason may be that it is cheaper.

Silicons Silicons can be stable, elastic, optically clear. They are an ideal choice, but the price of the mateiral is about 1 Euro/Watt. If one submerges 1 m2 of panel in silicons this takes about 0.7 to 1 liter. Silicons can be RTV (room temperature vulcanizing) in which case on can simply wait for it to cure. This is a very low energy solution.

Some heat cured silicons need degassing, which requires an expensive vacuum machine. This is mainly because small bubbles become big bubbles when heated.

ETFE This is an interesting material, it is durable, highly transmissive, cheap and very strong. It can serve as the outside layer, saving weight and cost when compared to glass. ETFE melts and can be welded, which makes it interesting to see if it can be used without EVA.

Laminates

Most common for panels
- Glass
- EVA
- Cells
-EVA
-Backplate (Acrylic, PVC)

Glass laminate
-Glass
-Silicon
-Cells
-Silicon
-Glass

Top laminate
-ETFE
-EVA
-Cells
-EVA
-Glass

Encapsulants

SYLGARD® 184
SE1740
Qgel330
QSil222
PV5700
STR encapsulants
Opti-tec 7020
Acrylic method patent (1983)
Polyurethane for solar applications
Polyamide encapsulant patent
Poly urethane patent (2006) (contestable)(known in 1988)Another patent
Clearpur (are working on formula)
Cold Bended Glass laminate

Desmopan
Encapsulation film
Etimex EVA sheets EVA
PVB (its use) product
ETFE (Teflon, Fluon, Hostaflon, Ertaflon en Gaflon)
ECTFE (Halar) Leverancier F-Clean Example of use
Trosifol

Cleaning Solder Residue

The flux pen acid is real nasty stuff, it will burn the throath and lungs. Use gloves in a well ventilated room, preferably with vetilation removing the damps to outside. Ultrasonic cleaner plus water and soap.
Ultrasonic cleaner of the right size

Resin and lamination sources

Cesense
Polyservice

Lamination processes

1. Vacuum laminator or bag
2. Vacuum ring
3. Nip Roller
4. Overpressure process (inner tube balloon)
5. Degassing > 29 inch hg

Videos

How they are made
Simple process
Adding tabbs
Failure modes
Degassing forum

Cells

The cells commonly available are:

3 by 6 1.8 Watt
5 by 5 2.5 Watt
6 by 6 3.6 Watt

If you can get tabbed cells that is much better (soldering the front is a pain). Read Ebay offers carefully, the actual output of the cells offered can disappoint. 'Short tabbed' or 'Double side tabbed' means recycled. About measuring the cells

Cel manufacturers can be reached here PVCellManufaturers

Huge Amorphous panels

Cost effective

Tabbing / Bus Wire

Tinned copper of the required cross surface for the expected current. You probably don´t need buss wire if there are no parralel strings