Types of Solar Energy

Solar energy can be broadly classified into Photovoltaic solar power and Thermal solar energy. Solar thermal energy is the energy created by converting solar energy into heat whereas Photovoltaic solar power is the energy created by converting solar energy into electricity using photovoltaic solar cells.

Concentrating Solar Power is a new form of solar thermal energy in which power is generated by focusing reflected sunlight at a point. In Solar PV power is generated by photoelectric effect.

Their working can be seen here:

CSP is highly efficient when compared to Photovoltaic but the downside is that it is costly. However when used to generate large quantities of power CSP may be economical. Hence solar PV technology dominates all  other types of solar energy. Now a days, Concentrated Photovoltaic (CPV) is also being used in which solar panels are parabolic and therefore, corresponding less land space is required; disadvantages include greater complexity of cell manufacture and price per kilowatt hour.

Current research in Solar PV technology: 

Quantum dot solar cells are an emerging field in solar cell research that uses quantum dots as the photovoltaic material, as opposed to better-known bulk materials such as silicon, gallium . Quantum dots have bandgaps that are tunable across a wide range of energy levels by changing the quantum dot size. This is in contrast to bulk materials, where the bandgap is fixed by the choice of material composition. This property makes quantum dots attractive for multi-junction solar cells, where a variety of different energy levels are used to extract more power from the solar spectrum.