Solar Cell Efficiency Improved When Stacked
Producing solar energy just got cheaper thanks to new, more efficient technology. Individual solar cells can only convert about one-third of the energy that they absorb into electricity. Stacking the cells increases the efficiency by about 50 percent. The biggest energy waste when it comes to solar panels is heat. How have researchers been able to limit waste?
The secret is a thin coating of gallium arsenide where the stacked cells are joined. This keeps the joints from breaking down at high energy levels. The breakdown of the junctions is where most of the energy loss takes place. A greater number of junctions equals more loss, but it is much more cost effective as far as the price of the panels is concerned. Thus, this coating may make a significant difference in the efficiency of stacked panels.
The compound makes the junction able to hold a dozen times more solar energy than is necessary for the process. So it should hold up even under the toughest conditions, keeping any significant amount of power from being lost.
You’re not going to be buying solar panels treated with gallium arsenide to put on your roof. It’s only cost effective for large scale operations at this time. The offset in cost occurs because it is cheaper to manufacture many smaller cells than one large one. Now the smaller cells can be even more efficient in their electricity production.
The key now is to find ways to get gallium arsenide produced at a low cost and in greater amounts. While it improves the efficiency of the cells greatly, an efficient way to produce large quantities of the substance in the needed form will determine just how cost effective it will be.