Global solar power is growing by the day. (Image Credit: Bru-n0/pixabay)
Solar power is growing at a rapid pace that humanity hasn't seen before. For instance, global solar grew tenfold over the last ten years, which saw installations doubling approximately every three years. The Economist claims the world could end up deploying solar energy equivalent to constructing eight times the global fleet of nuclear reactors. It took one year to install one GW of solar power in 2004, and now we've achieved that in just one day.
This surprised energy analysts. All of the International Energy Agency's (IEA) major forecasts significantly underestimated solar power's growth since 2009. In this case, they expected projections to transpire over two decades. But they occurred in six years instead.
Cost reductions have ultimately driven this rapid growth. Solar cell prices have decreased thanks to technology improvements and a boost in productivity. Apart from other energy shifts, from wood to coal, coal to oil, or oil to gas, solar doesn't require hard-to-access materials as it relies on silicon produced from sand.
However, energy needs to be stored for later use. Batteries are quickly improving, and prices have dropped, with estimates suggesting battery storage costs have decreased by 99% over the past three decades. Lithium, cobalt, and other minerals are still required, with plenty in Australia. The United States is looking into using trainloads of batteries to transport solar power rather than building power lines.
If those cost trends continue, solar could dominate global energy by 2060, overtaking nuclear, hydrogen, and wind. In Australia, solar has led to the price reduction of electricity, especially in states with heavy renewable usage, like South Australia and Tasmania.
The U.S. expects to connect 32.5 GW to the power grid in 2025. (Image Credit: U.S. Energy Information Administration)
More solar power capacity is quickly being added across the United States. It expects to connect 32.5 GW to the grid. Texas will have an additional 11.6 GW of solar power capacity installed. Meanwhile, Indiana, Arizona, Michigan, New York, and Florida will add 1 GW each, totaling 7.8 GW. In 2024, the U.S. installed a record-breaking 49 GW of solar capacity, which includes utility-scale and distributed solar. The Solar Energy Industries Association (SEIA) says the United States solar market installed 32.4 GW and saw a 51% increase in 2023.
According to SEIA's projections, solar power installation is expected to decline by 7% on average from 2025 to 2027. In addition, the market could contract by 2% annually between 2025 and 2030 in the Base case. After seeing a rapid growth in 2023 and 2024, the solar industry may face challenges like tariffs, policy uncertainty, labor shortages, and interconnection delays, which are expected to lead to slow growth.
The High Case scenario shows that solar installation could grow by 24% through 2034 relative to the Base Case. This is equivalent to 118 GW of additional capacity above the Base Case by 2034.
In 2023, China deployed 201.48 GW of new PV solar capacity, nearly tripling its 2022 growth and setting a global record. It also added 277 GW of solar capacity in 2024. China has installed over 1.08 TW of solar power capacity by the end of May 2025, a 56.9% year-on-year increase. According to the National Energy Administration (NEA), the nation's total power generation capacity reached 3.61 TW by the end of May, growing 18.8% compared to last year. From January to May 2025, China installed 197.85 GW of new solar capacity, an increase of 388.03% compared to the same period last year. In May, the country installed 92.92 GW of capacity, a 105.48% growth from April.
As good as photovoltaic solar power sounds for the world, it has some drawbacks. And these typically occur from production to disposal. As we know, most solar cells have a polysilicon composition, and these need quartz that is mined via the traditional method. This is a problem as it produces waste. And lots of it.
Refining raw quartz into polysilicon involves using industrial furnaces that release carbon dioxide and sulfur dioxide. This process also produces silicon tetrachloride, and when mixed with water, it forms hydrochloric acid. For every ton of polysilicon made, three to four tons of silicon tetrachloride waste is produced. According to Environmental Progress, solar creates 300 times more toxic waste per unit of energy compared to nuclear power.
Critical raw materials are essential for solar manufacturing. Although 6% of the world's total power production comes from solar, its expansion puts pressure on the supply and availability of high-purity quartz, silver, indium, tellurium, and other rare elements. As of 2025, solar panels cover over 6,000 square miles globally, according to the International Energy Agency. Every day, 2.5 square miles of solar panels are being installed, which leads to more solar waste concerns and end-of-life management.
Solar panels last 20-30 years, and many of them will start reaching the end of their operational life in the coming decades. In 2018, the International Renewable Energy Agency estimated that close to 80 million tons of photovoltaic panel waste could accumulate by 2050. Newer studies suggest that the figure could surpass 200 million tons, depending on how quickly panels are deployed, replaced, and retired.
Maximum current efficiency
Solar panels have come a long way, especially in terms of current efficiency. Twenty to thirty years ago, they had an efficiency of approximately 10%, which significantly improved due to research and development in this field.
Solar panels. (Image Credit: markusspiske/pixabay)
On average, commercial and residential solar panels have an efficiency of approximately 21%, and further research involving new materials could lead to higher efficiencies. Silicon is one of the most widely used materials in solar cell technology, serving as the foundation in the industry. Innovative technology, such as passivated emitter rear contact (PERC) and heterojunction cells, has enabled the most sophisticated silicon PV cells to reach 23-24% efficiency.
Perovskite-silicon tandem cells can reach 32.5% efficiency. (Image Credit: HZB)
There are also perovskite-silicon tandem cells, a solar panel technology that has a perovskite cell stacked on a standard silicon cell. Each of these harnesses the solar spectrum at different levels. The perovskite layer absorbs short wavelengths, and the silicon absorbs long ones. As a result, the tandem can achieve 32.5% efficiency in a laboratory. Oxford has already made plans to commercially deploy these cells by the end of this year, potentially revolutionizing utility-scale and residential markets.
Multi-junction cells achieved higher efficiencies—47% or more. These are used for aerospace and concentrated solar power (CSP) applications. However, multi-junction cells are too costly for mainstream use and show the potential of solar power in the future.
Biggest solar farms
Solar farms are growing and becoming more common around the world. (Image Credit: American Public Power Association/Unsplash)
Xinijiang Solar Farm:
Xinjiang, China, hosts the largest solar farm on the planet with millions of photovoltaic (PV) solar panels. It officially connected to the grid on June 3rd, 2024, boasting a capacity of 5.0 GW. The solar farm is so massive that it could generate enough electricity to power Luxembourg or Papua New Guinea for a year.
Tengger Desert Solar Park:
The Tengger Solar Park in China has over 3 million PV solar panels. (Image Credit: NASA Earth Observatory)
The Tengger Solar Park, known as "the great wall of solar" in China's Tengger desert, has over three million PV solar panels with an overall capacity of 1.5 GW. It generates enough electricity to power 600,000 homes in China. The State Grid Corporation of China constructed the park as part of the country's effort to switch to renewable energy.
Hunanghe Hydropower Golmud:
China's Golmud Solar Park in Qinghai Province has 80 individual solar plants featuring more than 7.2 million solar panels with a 2.8 GW capacity. Commissioned in 2018, this solar park uses PV solar panel technology and is included in the Qinghai Solar-Thermal Comprehensive Utilization Demonstration Project that incorporates different solar technologies, increasing energy output.
China is in the process of expanding this park by adding another 3 GW of PV solar panels and 300 MW of concentrated solar power. It expects to complete this project by the end of this year. Golmud will then become one of the largest parks with the highest capacity.
State-owned power company China Three Gorges Renewable Group is constructing a massive 8 GW solar farm in Ordos, Inner Mongolia. This $10.99 billion project is part of an integrated energy project and is expected to go online by 2027. When complete, the power will be distributed in the Beijing-Tianjin-Hebei region in northern China using an ultra-high voltage power transmission line. The farm will generate enough electricity to power approximately six million homes.
Mohammed bin Rashid Al Maktoum Solar Park:
The Mohammed bin Rashid Al Maktoum Solar Park has 2.3 million PV solar panels. (Image Credit: DEWA)
UAE's Mohammed bin Rashid Al Maktoum Solar Park is one of the largest solar farms in the world, with a capacity of 3.9 GW. It has millions of solar panels and uses PV and concentrated solar power technologies. By 2030, the park's capacity is expected to grow to 7.28 GW. The PV parts feature bifacial modules to capture sunlight on both sides and machine learning-tracking systems to ensure they achieve the highest efficiency. The CSP parts have a parabolic basin complex and the tallest solar power tower. This tower uses molten salt to store thermal energy, ensuring the park continuously generates power.
Technological advancements
Bifacial solar panel technology. (Image Credit: ScienceDirect)
Besides perovskite-silicon tandem cells, bifacial solar panels have emerged. This technology features solar panels on both sides of the unit, ensuring it captures direct sunlight and sunlight reflecting off surfaces, including the ground or water. Bifacial modules can produce 20% more electricity than other panels. That also means these panels are ideal for a wide range of applications, such as large-scale solar farms. The National Renewable Energy Laboratory (NREL) has developed bifacial perovskite solar cells with 91% to 93% bifaciality.
Transparent solar panels are an interesting innovation that can be deployed on windows, skylights, facades, and other surfaces. Made of transparent luminescent solar concentrators (TLSCs), this technology generates electricity without blocking out light or visibility. Transparent PV glass is different compared to PV modules. It absorbs near-infrared and ultraviolet wavelengths and allows visible light to transmit. Integrating transparent solar panels in buildings and windows has the potential to reduce urban power consumption.
MIT developed fabric solar cells capable of generating power on any surface. (Image Credit: MIT)
Flexible and lightweight solar panels can be a potential game changer, changing how solar panel modules harvest sunlight. This innovative technology uses extremely thin silicon, organic photovoltaics, and perovskites, allowing them to be installed on curved or uneven surfaces and other areas deemed impractical for standard panels. MIT developed lightweight, extremely thin fabric solar cells that can be placed on any type of surface, including plastic. Compared to traditional PV panels, these flexible solar panels produce 18 times more energy/kilogram. This technology is suitable for wearables, emergency response kits, and portable solar solutions. Thanks to its flexibility, the panel can conform to drones, vehicle roofs, and spacecraft.
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