Where should we put so much solar panels？

The 《Paris Agreement》 report concludes that efforts should be made to control global warming at 1.5 degrees Celsius, otherwise it will bring serious impacts such as sea level rise, extreme weather, ecological damage, and diseases. But time is running out, and solar energy still accounts for only 3.7% of energy production. We urgently need more solar energy. But where are we going to put the solar panels? They require a lot of space. Integrated photovoltaic technology plays a win-win role in multiple fields, and solar roofs in cities and towns are a typical example. Today, we will talk about other integrated photovoltaic technologies.

Agricultural photovoltaic 

Double sided solar panels, the land between them can be used to grow crops and livestock; Alternatively, the solar panel can be rotated towards the sun; Alternatively, it can be placed high enough to allow farmers to walk and work below, enjoying some shade. You may think that doing so will reduce crop yields, and not only will crops grow well, but tomato and chili yields will even double because they will stop photosynthesis under too much pressure. Solar panels can also protect the crops below from heavy rain and hail. Farmers can even resell excess solar energy to local people. Climate change means that such extreme weather is gradually increasing. It can also ensure that the required water for irrigation is reduced, making it very useful in another extreme condition: arid areas.

Although solar energy provides tempting returns, the investment cost is still more than twice that of ground installation, and you cannot use the entire field to grow food. Panel mounted sockets will occupy 1% -12% of the space, depending on the crop and photovoltaic system. However, the trend in the next few years is full of hope. According to market analysis agencies, the global market is expected to grow by 40% in the next five years. In arid regions and places heavily dependent on land, such as India, Indonesia, and many African and South American countries, agricultural photovoltaics can save a lot of water and land. Combining solar panels with land is a way to save land. How about installing solar energy on water?

Floating Photovoltaic Power Generation (FPV)

Solar energy is installed on a raft like structure floating on water, and only 10% of all available reservoirs in the world can provide a peak installed capacity of 23 terawatts. In the long run, these 23 terawatts of power generation are sufficient to meet the electricity needs of today's world within a year. According to a report published by the National Renewable Energy Laboratory (NREL) in the United States, floating photovoltaic can play a key role in the regional goal of the Association of Southeast Asian Nations (ASEAN), which is to achieve a renewable energy installed capacity of 35% by 2025. The report identified 7301 suitable water bodies for deployment of floating photovoltaics in Southeast Asia (88 reservoirs and 7213 natural water bodies). Overall, the floating photovoltaic potential of the reservoir is 134-278GW, and the natural water body is 343-768GW. Singapore may be one of the smallest countries in the world, but this prosperous financial center is one of the countries with the largest per capita carbon dioxide emissions in Asia. Although the authorities have been pushing to change this situation, renewable energy is a challenge in a country where there are no rivers to provide water for power generation and wind power is insufficient to drive turbines. Therefore, this tropical country has turned to solar power generation. However, in an area only half the size of Los Angeles, there is almost no excess land space. "After depleting the roofs and available land, the next huge potential is actually our waters," said Jen Tan, the head of the Southeast Asian solar department. Thousands of shining solar panels extend into the waters near Singapore, The solar energy here can generate 5 megawatts of electricity, which is enough to provide electricity for 1400 apartments for a whole year. The Dingzhuang Reservoir Photovoltaic Power Plant in Dezhou, Shandong, China can even provide clean electricity of 320 megawatts per year, save 168000 tons of standard coal, and reduce carbon dioxide emissions by 453000 tons.

Chinese Floating Power Generation

This is not all, under the solar version, you can also raise fish in aquaculture fences, which can generate additional income. Floating photovoltaic projects may be particularly useful for hydroelectric dams. In summer, solar panels can generate electricity - when the weather is humid, hydroelectric power can be started, and it can also cool the floating panels to make them more efficient. By protecting the water surface from sunlight, panels can reduce evaporation, making it a true delivery during climate change when water becomes increasingly precious. Water scarcity is a major issue, especially in arid regions such as sub Saharan Africa, Southeast Asia, or the Middle East. Under extreme conditions, up to 90% of rainfall may be lost due to evaporation. Floating solar panels can help solve this problem. According to a study in Jordan, using floating photovoltaic panels on reservoirs can reduce water loss by 42% compared to uncovered reservoirs. The use of such panels on inland water bodies is only the beginning. Floating panels on the ocean is more effective than floating on reservoirs, and ocean panels generate 13% more energy than on reservoirs because the ocean is more capable of cooling the system than lakes or lagoons, which will significantly improve power generation efficiency. The ocean space between offshore wind farms is usually large, and the middle can be used for floating solar energy.

Floating photovoltaic technology has the function of not occupying land resources, reducing water evaporation, blocking sunlight and inhibiting algae growth, and even providing additional profits for fish farms. So why are we only starting now? Part of the reason is cost, as floating solar energy requires specialized equipment and trained installation personnel. The structure of the panel must be able to withstand wind, waves, and corrosion. This means that their lifespan is longer than on land. This has resulted in their electricity generation prices being 2% -20% higher today. But experts say prices will significantly decrease in the future. Floating photovoltaics can reduce algae growth, reduce health risks, and reduce water treatment costs. But changes in water chemistry can also lead to nitrification and oxygen. So far, multiple studies have not found any serious impacts on water quality or ecosystems. Experts predict that the annual growth rate of floating photovoltaics will reach as high as 30% in the next five years, with the market mainly concentrated in Asia, but Europe, Africa, and the United States are also starting to invest.

Overall, integrated photovoltaic technology can achieve a win-win situation without occupying precious land resources, and is expected to become an important component of mainstream energy in the future, contributing to sustainable development and environmental protection. However, achieving these prospects requires the joint efforts of the government, enterprises, and research institutions to promote technological innovation, market promotion, and the formulation of regulations and policies.