Production of monocrystalline silicon is very energy intensive, and involves emissions of carbon.  There are emerging technologies for reducing carbon emissions and energy use, but they need to be improved if silicon production is to be completely sustainable

New processes such as electrodeposition are now easily able to provide cheaper and more environmentally friendly puresilicon

Chemical reduction processes utilising the catalytic properties of aluminium and manganese can allow the purification processes to operate at much lower temperatures, and these new processes are now commercial available

With a single crystal of silicon, the recombination losses are reduced so the solar cell is more efficient

Polycrystalline cells have a lower embedded energy content and so are more efficient

With a single crystal of silicon, the bandgap is , so the solar cell is more efficient

With a single crystal of silicon, the bandgap is smaller, so the solar cell is more efficient

Monocrystalline silicon and energy are the inputs, and polycrystalline silicon is the output

Phosphorus (for doping), polycrystalline silicon and energy are the inputs, and monocrystalline silicon is the output.

Polycrystalline silicon is the input, and monocrystalline silicon is the output

Polycrystalline silicon and energy are the inputs, and monocrystalline silicon is the output

Cell, panel, module, array

 Array, panel, module, cell

Module, cell, panel, array

Cell, module, panel, array

Everyone gets 12 hours of sunshine

It will depend on your latitude - higher latitudes will get less sunshine hours

No sunshine at the North Pole and 24 hours of sunshine at the South Pole

No sunshine at the South Pole and 24 hours of sunshine at the North Pole