Energy Transformation in the Low-Carbon Era: Harnessing the power of Renewable Energy

In 1996, a biologist discovered that the milkweed butterfly, typically seen in southern China, was spotted in the north. In August last year, a similar phenomenon was also observed in Beijing. The temperature in the northern hemisphere has been on the rise in recent years, and the climate change has affected worldwide ecology. Energy and environment will be humanity’s top ten problems for the next 50 years.

In 2021, the Nobel Prize in Physics was awarded to three scientists, Syukuro Manabe, Klaus Hasselmann, and Giorgio Parisi for their ground-breaking contributions to our understanding of complex physical systems. They established the foundation of our knowledge of Earth’s climate and how humanity influences it. The study explained in details the connection between the increase of carbon dioxide in the atmosphere, the rising temperature of Earth's surface, and how humanity influences it.

Figure | Timetable of countries achieving carbon neutrality goals

The question looms large over three areas of concern: how can we develop low-carbon technologies, achieve the "Dual Carbon" goal, and solve energy and environmental problems? Low-carbon technology encompasses three aspects: carbon reduction technology, zero-carbon technology, and decarbonization technology. Zero-carbon technologies such as nuclear, solar, wind, hydro, and biomass energy have received broad social attention, because of their “clean” nature, as these energy sources only emit carbon dioxide when they are in utilization.

Solar will be central driver of the "Dual Carbon” goal

Fossil-fuel energy is a non-renewable energy source that will be depleted eventually. Solar energy resources are however plentiful. According to scientific calculations, some people have calculated that if one were to cover the Taklamakan Desert in Xinjiang, China, with raised solar panels, one would produce about 6.6x1014 kWh of solar energy each year. According to China's 2020 electricity consumption statistics, the whole of China consumed about 7.5 trillion kilowatt-hours (kW·h) of electricity in a year. This means that the amount of solar energy produced by Taklimakan Desert is adequate to support the entire electricity consumption of all people and industries in China.

On one hand, the potential of solar energy resource utilization is limitless On the other, China faces great pressures to reduce emissions. According to the Xx 2018, it was reported that raw coal accounted for 61.9%, crude oil 19.1%, natural gas 7.2% of . and clean energy at just 11.8%. In 2020, China has the highest overall level of carbon dioxide emissions, producing about 10 billion tons.

Figure | Structural comparison of primary energy demand among countries in 2018

The Chinese Academy of Sciences has formulated an action plan to focus on the developments of photothermal, photochemical, and photobiological energies. The plan also covers the intensive development of smart distributed energy systems and energy IoT technologies, as well as the promotion of broad applications of local solar technology.

According to the information shared by the director of Sungrow Power Supply, Weng Jie, at the IIC (International IC & Component Exhibition and Conference) 2022 congress, the cost of wind power and energy storage is falling rapidly. Over the past decade, the cost of photovoltaics has dropped by 90%, while the cost of wind power has dropped by 25-40%, and the cost of energy storage has dropped by more than 80%. At present, the levelized cost of energy (LCOE) of photovoltaic and wind power is lower than that of power from coal.

Figure | LCOE trends in China's photovoltaic and wind power and their energy storage systems

The cumulative installed capacity of photovoltaics in China in 2021 exceeded 300GW and is expected to exceed 5000GW by 2050. In 2050, the amount of power generated by photovoltaics will account for 39% of the country's total power generation, making it the main power supply in China by then. This goes to show how solar energy will be the core driver of the "Dual Carbon" goal.

The development of the photovoltaic industry is inseparable from semiconductors

Photovoltaic power generation is the process by which light energy is directly converted into electrical energy using the photovoltaic effect of the semiconductor interface. The photovoltaic industry chain comprises high-purity polysilicon in the upstream, photovoltaic cells, photovoltaic modules, rectifiers, inverters and transformers in the midstream, and mainly photovoltaic power stations in the downstream, all of which are closely related to semiconductors.
Let’s take the midstream inverter as an example. In fact, there are many types of photovoltaic inverters, namely household inverters, string inverters, and centralized inverters.  More recently there have been optimizers and string inverters, microinverters, shutdown gateways and string inverters, as well as other new types of inverters.

The core components of photovoltaic inverters are power components. From the perspective of single-tube, there are mainly single insulated gate bipolar transistors (IGBT), SiC diode, CoolMOS, and SiC MOSFET. In terms of modules, there are mainly PrimePack series, Econodual series, and white modules. In addition, photovoltaic inverters need to be powered by MCU, MPU, PMIC, and other semiconductor IC.

According to the information shared by CR Micro Vice President, Ma Weiqing, at the 2022 World Semiconductor Conference, a 500kW centralized inverter needs 12 1200V/600A IGBTs, and a 25kW three-phase string inverter needs from 12 to 16 single IGBTs and 2 SiC diodes.

Besides, according to public information from a leading photovoltaic inverter company in China, its total procurement in 2019 amounted to RMB 567 million. Raw material semiconductor devices mainly include IGBTs, MOSFETs, and SiC diodes. The procurement amount of IGBT-based power devices was RMB 60 million , accounting for 10.6% of the total procurement amount. Therefore, the development of the photovoltaic industry   has a close, direct relationship with the progress of semiconductors.

Endnote:

The goal of the "Dual Carbon” aims to transform the energy structure from one that mainly relies on fossil energy to one that runs on zero emission sources suxh as wind, photovoltaic, and hydro power. The dynamic development of new energiesis key to achieving carbon peaking and carbon neutrality goals.

The Dual Carbon goal is accelerating China's photovoltaic industry into a period of rapid expansion. At Avnet, we are confident that the development of photovoltaics will contribute significantly to a more sustainable world.