Difference between solar thermal and photovoltaic power generation
There are two types of technology for generating electricity from solar power – photovoltaic and solar-thermal. These two concepts exploit the sun as an energy source, but differ in terms of their manageability and their adaptation to demand.
Population growth poses a challenge for humanity, as it leads to an increase in the demand for electricity. The solution to this challenge is complex because it requires the development of clean and sustainable electricity systems. Only in this way can we limit the effects of climate change, which has been definitively linked to the greenhouse gas emissions produced as a result of human activity. Solar power is one of the major alternatives in this field, involving the use of two main types of technology:
Solar thermal energy
Solar-thermal technology concentrates the sun’s power to obtain thermal energy. This thermal energy is used to generate steam, which in turn operates a conventional turbine that produces electricity. Solar-thermal power generates electricity in a manageable way, in other words, on demand. There are two main types of commercial solar-thermal technology – tower and parabolic trough technology. At present, these account for almost 4 GW of installed power, of which 3,370 MW comes from parabolic trough plants and 538 MW comes from solar-thermal tower plants.
” Solar-thermal power can be managed to adapt energy production to demand at any given time.
The market for solar-thermal technology is determined by direct solar radiation (known as Direct Normal Irradiance or DNI), which is the radiation that reaches the earth’s surface directly from the sun without interference from particles, clouds or other elements. The United States and Spain are the countries with the largest installed capacity of solar thermal technology. However, important growth is being recorded in countries like South Africa and Morocco and it is also set to become part of the energy mix in Chile, India, China and other countries in Latin America, the Middle East and North Africa.
Photovoltaic technology uses solar radiation to generate electricity by exploiting the chemical properties of certain materials. This technology generates electricity directly via the photoelectric effect, in other words, as a result of the effect of solar radiation on semiconductor materials. The impact of solar energy on the atomic structure of semiconductor materials generates a continuous electrical current. Photovoltaic modules use this process to generate power when this material comes into contact with light.
” The development of photovoltaic power is dependent on the development of storage systems to overcome the issue of intermittent production.
Photovoltaic technology is used worldwide, mainly in China, Germany and the United States. The total global installed power is currently 145 GW, much of which is devoted to self-sufficiency. The evolution of this technology is dependent on the ability to overcome its major challenges – development of the module manufacturing market and, above all, storage system innovation in order to overcome the intermittent nature of photovoltaic energy production.
|Manageable, which means production can be adapted to energy demand.||Low-cost.|
|Can be hybridized with fossil fuels like natural gas. In conventional plants, this can reduce pollution from atmospheric gas emissions. This can also prolong its useful life.||Wide geographical area of application.|
|Promotes socio-economic development by creating employment and industrial infrastructure, which encourage technological development, innovation and entrepreneurship.||Low maintenance costs: photovoltaic technology does not need major economic investment and human resources for its maintenance.|