Solar farms: the global path towards clean energy
Today, solar farms have become one of the pillars of the transition to a sustainable energy model. In 2021, the total cumulative installed capacity of solar electricity amounted to around 191 gigawatts (GW) globally, a 32.6% rise from 2020 (144 GW). Similarly, a gradual rise to 223 GW is projected for 2023.
What are the technical elements that guarantee the optimal performance of solar farms? Let’s have a look at what a solar farm is and the facilities with the highest production rates in the international context.
Solar farms: countries at the forefront
World solar energy generation registered 855.7 terawatt-hours (TWh) for a growth rate of 20.5% in 2021. Among the countries with the highest performance rate and infrastructure of solar farms, we can find:
• China: 261.1 TWh and 253.8 GW.
• The European Union: 146.1 TWh and 128.7 GW. The following countries stand out in this group: Germany (50.6 TWh and 53.8 GW), Italy (26 TWh and 21.6 GW), Spain (20.8 TWh and 11.8 GW), France (13.1 TWh and 11 .7 GW), and the Netherlands (8.1 TWh and 10.2 GW).
• The United States: 134 TWh and 73.8 GW.
• Japan: 82.9 TWh and 67 GW
• India: 58.7 TWh and 39 GW
China dominates the market due to two specific factors. Firstly, the development of different long-term investment projects. For example, a 10 GW photovoltaic factory in solar cells is worth US$7 billion. This enables competitive prices that rival those offered by fossil fuels.
Secondly, we find the opening in the exploitation of raw materials. The Chinese industry has seen an alternative to solving the demand for solar panels in polysilicon. Nowadays, the country has increased its production rate by 1.5 million tons.
As for the European Union, the picture is encouraging. Spain represents the core of the investments since it has 35% more solar radiation. This means that a 35% return is obtained for every euro invested. Ultimately, the main challenge for the European Union points to overcoming gas usage.
Solar farms and their operation
Solar power farms consist of the interconnected assembly of large-scale solar panels to supply the electricity grid. Thus, they are primarily located in territories with few or no productive activities and high light radiation (deserts for example). We can even find projects for plants situated on bodies of water.
For their operation, solar farms are based on the system detailed below:
These are devices that generate electricity through a photovoltaic effect. Each panel implements a series of cells (between 60 and 72) made of silicon, boron, and phosphorus, in individual areas of 10cm2.
The interaction between a panel’s surface and the light particles (photons) produces positive or negative charges which are transformed into continuous energy. The arrangement of panels in solar farms can be fixed (same direction and inclination) or with a mechanism responsible for rotating them towards sunlight.
A frame composed of:
• Aluminum coating that assembles and protects the pieces.
• EVA (ethyl-vinyl-acetylene), a material resistant to heat and ultraviolet radiation to prevent cell deterioration.
• Cover for conductivity and thermal insulation.
This is a connection specialized in transmitting the energy generated by each panel in a solar plant. Made of copper, it is characterized by its flexibility, long life (30 years), and tolerance to temperatures between 90Cº and 120Cº.
These are responsible for converting direct current (coming from the panels) into alternating current.
The Transformation center regulates the flow of alternating current for its adequate distribution in the electrical network.
The battery field accumulates energy for use at specific times, such as in the absence of sunlight.
Solar farms: world productivity ranking
Once the components of solar farms have been defined, we can recognize the social and ecological importance of constructions such as:
Bhadla Solar Park (India)
The largest solar farm in the world (World Energy Trade, 2021). It received this title after a recent addition of 300 megawatts (MW), reaching a total of 2,245 MW. It is 5,700 hectares long, and it is located in Bhadla, Jodhpur (in the district of Rajasthan).
Its operation is based on a public-private alliance with assignments of:
• 745 MW to the government of India.
• 1 GW to IL&FS and the government of Rajasthan.
• 500 MW to Adani Enterprise, government of Rajasthan.
This park holds the title of the cheapest clean energy facility in India, with 4.1 cents per KW/h in 2017 and 3.8 cents per KW/h in 2019.
Developed by the state-owned company Huanghe Hydropower Development, this farm covers 5,000 semi-desert hectares in Gonghe County, Hainan Prefecture (Qinghai-China). Estimated at €$1,885 million, its investment represents a production margin of 2.2 GW and storage systems of 202.8 MW/h.
It is the Chinese project with the most significant social reach in two senses (Bellini, 2020):
• It supplies cheap electricity (0.0426 euros per kW/h).
• It covers the densely populated provinces of Qinghai, Gansu, Shaanxi, and Henan with a 1,587-kilometre (ultra-high-voltage) cable.
Francisco Pizarro (Spain)
Through its subsidiary in Spain, the Iberdrola group will build the Francisco Pizarro project, the largest solar farm in Europe. It will start its operation this year. Located in the Cáceres municipalities of Torrecillas de la Tiesa and Aldeacentenera, it has an area of 1,300 hectares for a capacity of 590-megawatt peak (MWp).
Its main positive attributes are:
• An investment of 300 million euros, with a minimum of 1,200 jobs created during its start-up.
• The reduction of greenhouse gases, given that 245,000 tons of CO2 will not be emitted per year.
• The supply of clean energy to 375,000 people in Cáceres and Badajoz.
H3: Nunez de Balboa (Spain)
Also owned by Iberdrola, it is the largest European solar farm. Located in Usagre (Badajoz), it has 1,430,000 solar panels, with a capacity of 500 MWp in 1,000 hectares. This means that:
• Renewable electricity is supplied to 250,000 people in Cáceres and Badajoz (832 GW/h per year).
• The emission of 215,000 annual tons of CO2 is prevented.
• 1,700 local jobs are guaranteed.
Núñez de Balboa is a project which is constantly evolving:
• Iberdrola plans an expansion of 2,000 new MW, with the photovoltaic and wind convergence in Extremadura, by 2022, and about 10,000 MW for Spain, in 2030.
• There are investments of 8,000 million euros to support the consolidation of scientific and technical infrastructure, in addition to the creation of 20,000 jobs.
Sola Star Solar Farm I and II (United States)
This farm is owned by MidAmerican Solar and is located near Rosamond, California. It is the largest solar power farm in the country, with a productivity of 597 MW, on a 13 km2 piece of land.
Indeed, its advantages manifest in its management of resources. Unlike other solar farms in the country, which use up to 9 million panels, Sola Star Solar Farm uses 1.7 million. The secret lies in its more efficient panels, mounted on fans directly absorbing sunlight.
Solar farms represent a clear trend towards renewable energies. The construction of these facilities not only guarantees the production of clean energy, but also an innovative socio-economic model. In each of the countries reviewed, the development of alternative electricity generation has a positive impact. It is necessary to keep up the pace of competitiveness and support these ecological transition initiatives.
BibliographyBellini, E. (2020). Se conecta a la red en China la planta solar más grande del mundo.
Bloomberg. (2021). En China se planea construir una fábrica solar de 7.000 millones de dólares que funcione con energía limpia.
BP. (2021). Statistical Review of World Energy.
BBVA. (2022). ¿Qué son los paneles solares, cómo funcionan y cuál es su futuro?
Iberdrola. (n.d.). Francisco Pizarro, el mayor proyecto fotovoltaico de Europa.
Iberdrola. (n.d.). Núñez de Balboa, la mayor planta fotovoltaica de Europa.
NS Energy. (2021). Las cinco principales plantas de energía solar de la India.
Ojea, L. (2022). España, el nuevo ‘Texas europeo’: 2022 será solo el comienzo del impacto de las inversiones en fotovoltaica.
Revista Empresarial & Laboral. (n.d). Granjas solares, una alternativa sostenible que toma fuerza en Colombia.
Roca, J. (2020). La mayor planta fotovoltaica del mundo se sitúa en India y tiene una potencia de 2.245 MW.
Roca, J. (2020). Las 20 mayores plantas fotovoltaicas del mundo: India manda en el ranking y España entra en el Top 20.
Roca, J. (2021). Se espera nuevo récord de instalación de energía solar en 2021, hasta los 191 GW.
Top Cable. (n.d.). ¿Qué condiciones son importantes a la hora de elegir un Cable Solar?
World Energy Trade. (2022). Los gigantes chinos de la energía solar tienen una solución para sus problemas de materia prima.