People often ask me “Why are Solar Panels Expensive?” and I thought it is best to explain it here once and for all.
Most people think that a Solar Panel is just Silicon Diodes. So let me explain what a Solar Panel is made up of:
- Silicon Diodes
- Aluminum Frame
- Glass Protective Layer
The Silicon Diodes take up about 50% of the total cost. The rest of the expense is in commodity metals like Aluminum. The prices of these other metals are pretty stable over a period of time.
The Silicon Part of the Solar Panel, of course follows Moore’s law.
Also, the problem lies in the efficiency of the Absorption co-efficients. Most diodes in commercials panels are pretty in-efficient.
This means: Only 18 to 21 % of energy is absorbed and converted to electricity at STC, in the field they absorb abysmal <15%
These factors make per-watt cost of Solar Panel more expensive.
If we just double the panel efficiency, we could use 50% less aluminum, 50% less glass and 50% less silicon for the same wattage.
So instead of ‘Why?’, the real question should be..
How can we make Solar Panel less expensive?