- 90% of the solar panels in the market today are made of polycrystalline Si. The remaining 10% are made of inorganic materials.
- The largest demand is Germany and the largest supplier is China.
- Solar is growing at the fastest pace than other major renewable energies. Although its capacity factor is the lowest.
- Cost wise, the PV system has dropped below 1 USD/W. The non-modular cost such as maintenance fee, racking, wiring, inverters remain pretty much the same so the falling cost of modules are the main contributors to the falling price of solar PV.
- Irradiance = power per unit area (watts per sqm)
- Spectral power density = incident power per unit area and per unit wavelength
- The sun is a black body radiator (which is not reflective and absorbs all light). The higher the temperature of black body radiator, the higher the photon energies.
- Solar spectrum is distributed 9% UV, 44% visible range, 47% infrared.
- The amount of irradiation is affected by things like atmospheric mix (CO2, oxygen, water).
- 20% of irradiation is reflected by clouds, 6% by molecules and 4% earth’s surface.
- 19% absorbed by earth’s surface
- Total lost = 49% of irradiation when hit on earth’s surface.
- Solar irradiance is expressed in sun hours where earth is exposed to 1000watts per sqm. Places like Spain with more sun has around 4.2 sun hours daily.