3.6 Concentrating solar or solar photovoltaics: Who is winning the game?
Both concentrating solar and solar photovoltaics could attract much attention during the energy crisis in the 1970s, triggered by the OPEC embargo in 1973. However, it was not until the early 2000s that solar photovoltaics had an appreciable grid-penetration. Concentrating solar power was the giant in the solar energy industry until the beginning of the 21st century. Anyhow, it could not maintain its glory all along the line. Solar photovoltaics started an outstanding and progressive journey. They just emerged as a little child and then started to compete with concentrating solar thermal technology, aggressively.
Concentrating solar thermal has been trampling from the very beginning of the 21st century and notably after 2008. To illustrate, let us take a look at the following chart which explains what happened to the solar energy market in the USA during 2000-2009.
Figure 01: Cumulative solar photovoltaics and concentrating solar thermal capacities in the USA 
The chart clearly illustrates that concentrating solar has lost its fame in 2005. Further, it can be noticed that the cumulative solar photovoltaic capacity has been skyrocketing from the beginning of the 21st century though no significant change has been made by concentrating solar power during the same time period.
Firstly, scalability is one of the secrets that photovoltaic technology dominates in the solar energy industry with a cumulative worldwide capacity of 308 GW whereas the cumulative capacity of concentrating solar thermal was merely 6 GW by 2016, as illustrated by the column chart below .
Figure 02: Worldwide cumulative solar photovoltaic and concentrating solar thermal capacities in 2015 & 2016 [2, 3]
As we can see it, the cumulative capacity of solar photovoltaics has grown by 81 GW to reach a capacity of 308 GW by 2016 from 227 GW in 2015. It is, however, interesting to see that the growth of concentrating solar thermal is merely 1.2 GW during the same period of time. The outstanding difference manifests the degree of practical feasibility associated with two technologies.
Above chart implies: Solar photovoltaics is far feasible than concentrating solar thermal. We otherwise would have had a very different column chart with blue colored columns instead of red colored columns and red colored columns instead of blue colored columns!
Overestimations are the most reliable
Enthusiasm is of paramount importance. Nowadays, many countries are keenly encouraging the investors for solar photovoltaics. Especially, China which is always trying to break world records is now breaking even their own records. Previously, they had set a target to reach 105 GW of solar photovoltaic capacity by 2020. However, they could exceed the target readily in 2017 with a capacity of 112.3 GW by July 2017 setting a new target of 213 GW for 2013.
Compare the China’s new target (2013 GW) with the previous target (105 GW). They have doubled their own previous target for 2020. This means the solar photovoltaic capacity has been expanding at an unpredictable rate making the forecasts extremely sterile.
Figure 03: China’s previous and revised targets for solar photovoltaic capacity by 2020
China is now guiding the world towards a Sun-powered society braking their own targets. Estimations are being exceeded making overestimations the most reliable…
Potential in the Sunbelt regions
Today, China, Germany, Japan, USA, Italy, UK, France, India, Australia and Spain are top ten leaders with large solar photovoltaic capacities. We can see that most of these are outside the Sunbelt which receives a much weak amount of solar irradiance compared to the Sunbelt countries. Therefore, these incredible achievements reflected by countries outside the Sunbelt (Germany, France, etc.) clearly have brought to light an unbelievable potential for solar photovoltaics in Sunbelt countries such as India, Pakistan, Bangladesh, China, Myanmar, Sri Lanka, USA (South), etc. as Sunbelt countries receive a great deal of solar radiation throughout the year. Anyhow, most of Sunbelt countries have not yet understood the value of solar energy which can be made a God’s gift if exploited properly.
Through hard work and perseverance, Germany could work its way up to the country with the second largest photovoltaic capacity. Being a country outside the Sunbelt, Germany is an obvious showcase to both Sunbelt and snowy countries like France and the UK for successful adaption of photovoltaic technology. Developing countries are, however, far lagging behind the European countries even though most of the developing countries are located within the Sunbelt. Anyway, a large majority of developing countries located in the Sunbelt like China, India, and Morocco are now increasingly turning towards solar photovoltaic technology.
No one can predict to what extent solar photovoltaics are going to serve the world.
But one evident fact from the recent past…
Solar photovoltaics would keep breaking the pre-set estimations…
Discouraging to predict the cumulative capacity but heavily encouraging to invest in photovoltaics….
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 Kumar, V., & Goyal, N. (2018). Comprehensive Study of Different Renewable Energy Resources such as Hydro Energy, Solar Energy and Wind Energy.
 Kabir, E., Kumar, P., Kumar, S., Adelodun, A. A., and Kim, K. H. (2018). Solar energy: Potential and future prospects. Renewable and Sustainable Energy Reviews, 82, 894-900.
 Mathews, J. A. (2017). China’s Electric Power: Results for first half 2017 demonstrate continuing green shift. Asia-Pacific Journal: Japan Focus, 15 (17).