Cheap solar panel built in one day

42 Monocrystalline cells @ 1.75W each

 

Abstract   A 42 cel1 solar panel was constructed in less than a day using low cost materials available from the hardware store. The enclosure was constructed out of plywood and coated in highly reflective mylar. The cells were joined together in series and glued on spacers on top of the mylar. UV resistant polycarbonate sheeting was used to protect the panel and to reflect tangental onto the cells.   Keywords: Solar cells,Photovoltaic,PV,diy solar panel

 

LIST OF FIGURES

Figure
1	Left: The back of the solar cell with copper wires. Right: Top of the cell with six points pre-soldered onto the conductive strip.
2	A temperature controlled soldering iron using a variac.
3	Top: Top view of the cells soldered together in series. Bottom: Bottom view of the cells soldered in series
4	The cells soldered in series in three rows of seven on top of a wooden base.
5	An enclosure constructed using wooden ends to fit the corrugated polycarbonate sheeting over the top of the base.
6	Highly reflective mylar sheet was glued to the walls of the enclosure.
7	The cells glued to shock absorbing cardboard.
8	The polycarbonate sheet screwed to the wood.
9	The corrugated dome catching additional tangential light which would normally be lost with a flat panel.
10	The cells output is currently undergoing practical testing.

 

 

1. Connecting the solar cells together.

 

Strands of copper wire were tinned and soldered to the pads on the back of each cell. Six points were pre-soldered on the conductive strip on the top of the solar cell with a low temperature soldering iron. We adjusted the temperature of the soldering iron using a variac.

 

 

Figure 1. The back of the solar cell with copper wires attached (left). The top of the solar cell with six points pre-soldered onto the conductive strip (right).

 

 

Figure 2. A temperature controlled soldering iron using a variac.

 

 

Cells were connected together in series by soldering the three lengths of copper wire to the top of the next cell.

 

 

 

Figure 3. Cells are soldered together in series. Top view (top) and bottom view (bottom) are both shown.

 

Three rows made from seven cells were connected in series to make a panel. (Two panels were constructed).

 

 

Figure 4. The cells soldered in series in three rows of seven on top of a wooden base.

 

 

2. Constructing an enclosure.

 

Wooden ends were cut to fit the corrugated polycarbonate sheeting. The polycarbonate sheeting protects the cells from physical damage and also protects the panel from UV light.

 

 

Figure 5. An enclosure constructed using wooden ends to fit the corrugated polycarbonate sheeting over the top of the base.

 

 

Highly reflective mylar sheet was glued to the surface of the wooden enclosure. This was used to reflect thermal radiation away from the base of the panel.

 

Figure 6. Highly reflective mylar sheet glued to the walls of the enclosure.

 

Cardboard shock absorbers were glued between the fragile cells and the mylar sheet to hold the in place and protect them from cracking,

 

 

Figure 7. The cells glued to shock absorbing cardboard.

 

The polycarbonate sheet was screwed to the curved plywood ends. Power is connected by brass bolts that protrude through the wood.

 

 

Figure 8. The polycarbonate sheet screwed to the wood.

 

 

 

Figure 9. The corrugated dome catches additional tangential light which would normally be lost with a flat panel.

 

 

 

Figure 10. The cells output is currently undergoing practical testing.