Currently, my country is at a critical stage of innovation-driven development, facing the challenge of transitioning from high-speed growth to scientific development, and confronting the existing division of labor and roles in the global value chain. We must, based on my country's fundamental national conditions and the international environment we face, and in line with national strategy, select and cultivate major technologies that can "support" and "lead" my country's economic and social development, striving for new breakthroughs to seize the initiative in my country's development and enhance my country's international standing.
The term "major technology" refers to technologies that occupy a core and crucial position among numerous technologies. Specifically, its importance is measured on three levels: first, whether it is fundamental; second, whether it is public; and third, whether it is strategic. Major technology is neither a mechanical addition nor a multiplication of these three indicators, but rather a fusion of fundamental, public, and strategic aspects.
Currently, the core of the Third Industrial Revolution is the new energy revolution. High-efficiency solar cell technology, as a key to improving solar energy utilization, represents an advanced technological development direction and has a significant impact on the structural adjustment and sustainable development of my country's photovoltaic industry. It is one of the major technologies that should be developed at present. Regarding high-efficiency solar cell technology, the question is no longer "whether to develop it, but how to develop it better."
Current Status of High-Efficiency Solar Cell Technology
Given the abundant, inexpensive, safe, pollution-free, and freely usable nature of solar energy resources, its utilization is increasingly attracting the attention of governments and the general public worldwide. Solar power generation, as an important form of solar energy utilization and a sustainable energy alternative, has experienced rapid development in recent years.
Based on technology, solar power generation is mainly divided into two categories: photovoltaic (PV) power generation and concentrated solar power (CSP). PV power generation, with solar cell technology at its core, directly converts solar energy into electricity. Currently, due to high costs, this technology has not yet become widespread. However, with continuous improvements in solar cell technology, increased economies of scale, and declining prices, PV power generation, based on high-efficiency solar cell technology, will be widely used.
1. Technical characteristics of high-efficiency solar cells
Solar cells (SCs) have advantages such as durability, cleanliness, and flexibility. Furthermore, they produce no pollution or noise during the conversion process. They can directly supply off-grid power to small appliances or generate electricity on-grid, making them a promising technology for applications.
Solar cells are the core of photovoltaic power generation systems, and their development and manufacturing are the most critical and important link in the photovoltaic industry chain, directly affecting the popularization and development of solar power generation. Effectively improving the photoelectric conversion efficiency of solar cells, reducing manufacturing and application costs, and achieving stable power generation are key issues that must be addressed in the development and manufacturing of high-efficiency solar cells.
Currently, the photoelectric conversion efficiency of ordinary solar cells in the industrialization stage is approximately 18%-19% for monocrystalline, 17.3%-17.8% for polycrystalline, and 8%-9% for amorphous silicon thin films. According to the "Opinions of the State Council on Promoting the Healthy Development of the Photovoltaic Industry," newly established photovoltaic manufacturing projects should meet the following requirements: a conversion efficiency of no less than 20% for monocrystalline silicon photovoltaic cells, no less than 18% for polycrystalline silicon photovoltaic cells, and no less than 12% for thin-film photovoltaic cells.
A solar cell is a semiconductor device that converts solar energy into electrical energy using the photovoltaic effect. Its core raw material is a semiconductor material that can release electrons. Solar cell products are mainly divided into: solar cells represented by crystalline silicon cells; solar cells represented by thin-film cells such as silicon-based thin-film cells, cadmium telluride (CdTe) cells, copper indium selenide (CuInSe) cells, cadmium sulfide (CdS) cells, copper indium gallium selenide (CIGS) cells, and gallium arsenide (GaAs) tandem cells; and new types of solar cells and new concept cells such as dye-sensitized photoelectrochemical cells (Grātzel cells), organic cells, multi-junction (bandgap-gradient) cells, and hot carrier cells.
As of the end of 2013, crystalline silicon solar cells (mainly P-type monocrystalline silicon cells and polycrystalline silicon cells) dominated the market, with a market share of over 90%; thin-film cells had a market share of less than 10%; and most new cells and new concept cells were still in the laboratory or pilot-scale stages and had not yet been industrialized on a large scale.
Currently, the global photovoltaic industry is still in its introductory phase, with various related technologies for high-efficiency solar cells developing in parallel. Among them, crystalline silicon high-efficiency solar cells have advantages such as high photoelectric conversion efficiency, low pollution, stable performance with minimal degradation, and mature large-scale manufacturing technology. Therefore, the high-efficiency solar cell structure dominated by crystalline silicon solar cells worldwide is not only a true reflection of the past few years but will also continue to dominate for the next decade or more.
However, to achieve the aforementioned efficiency requirements in current large-scale production, we may need to shift from conventional P-type crystalline silicon technology to P-type crystalline silicon PREC/PERT technology and N-type cell technology (including N-type bifacial, heterojunction, back-contact, and heterojunction back-contact cells). Meanwhile, compared to crystalline silicon cells, thin-film cells offer greater potential for improvement in photoelectric conversion efficiency, cost, and stability. Breakthroughs in thin-film technology are expected to make it a hot topic in the future development of high-efficiency solar cells.
Here, we will briefly explain the three main types of high-efficiency solar cells.
(1) High-efficiency crystalline silicon solar cells
Crystalline silicon solar cells mainly include monocrystalline silicon (mono-Si) cells and polycrystalline silicon (poly-Si) cells. Their manufacturing process is relatively complex, and the industry chain includes the entire chain from silicon raw materials (quartzite, quartz sandstone, etc.) to polycrystalline silicon to silicon ingots (rods) to silicon wafers to photovoltaic cells to photovoltaic systems. Technically, crystalline silicon is not the optimal material, but due to its ease of acquisition and the compatibility of its smelting technology with chemical and electronic industries, crystalline silicon solar cells have become the mainstream technology in the current photovoltaic cell market.
Crystalline silicon solar cells boast a theoretical photoelectric conversion efficiency of 31%, but suffer from drawbacks such as complex smelting and purification processes and high energy consumption. Furthermore, the efficiency gap between polycrystalline silicon and monocrystalline silicon cells is gradually narrowing, with polycrystalline silicon offering advantages such as lower manufacturing costs and higher output per unit area. Therefore, polycrystalline silicon (and mono-like poly-Si) cells are gradually surpassing monocrystalline silicon cells in market share, becoming the mainstream product and likely to continue playing this role in the future. Simultaneously, as the proportion of cell cost in system cost gradually decreases, high-efficiency cell modules remain advantageous in end-system applications.
In general, the technological development direction of crystalline silicon high-efficiency solar cells is low cost, high efficiency, and high stability, which mainly includes improving efficiency, reducing costs, and extending module lifespan. Specifically, improving efficiency depends on improvements in processes, materials, and cell structure; reducing costs depends on lowering the cost of existing materials, simplifying processes, and developing new materials; and extending module lifespan depends on improvements in module encapsulation materials and processes. Therefore, the research and industrialization of crystalline silicon high-efficiency solar cells, besides relying on expanding the industry scale, may depend not only on improvements in process technology but also, and perhaps more importantly, on improvements in industrial technology (including equipment and raw materials), particularly the establishment of new structures and processes.
(2) Thin-film high-efficiency solar cells
Thin-film solar cells are made by depositing a very thin layer of photosensitive material on substrates such as glass, plastic, and stainless steel to achieve photoelectric conversion. They mainly include four types: amorphous/microcrystalline silicon thin-film cells, cadmium telluride (CdTe) thin-film cells, gallium arsenide (GaAs) thin-film cells, and copper indium selenide/copper indium gallium selenide (CIS/CIGS) thin-film cells.
Among them, non-crystalline silicon thin-film batteries have the lowest photoelectric conversion efficiency, generally 6%-9%, and their raw material is silane, which is the most readily available. CdTe thin-film batteries have the next highest photoelectric conversion efficiency, at approximately 8%-11%. CIS/GIGS thin-film batteries have a relatively high photoelectric conversion efficiency, at approximately 10%-12%, and their raw materials contain rare element compounds such as indium, gallium, and selenium, which are scarce and difficult to obtain. Furthermore, ensuring a strictly uniform ratio of multiple elements remains a major challenge in the fabrication and application of large-area batteries.
GaAs thin-film solar cells have the highest photoelectric conversion efficiency, approximately 20%-30%. However, their raw materials include gallium, a rare element compound, which is scarce and difficult to obtain. Arsenic is toxic and can pollute the environment. In contrast, CIS/GIGS thin-film solar cells offer lower cost, more stable performance, and stronger radiation resistance, making them potentially one of the most promising photovoltaic cells of the future.
Overall, the technological development direction of thin-film high-efficiency solar cells is towards low cost, high efficiency, and high stability, with enormous future development prospects. Continuous improvement and refinement of production processes to reduce costs may be key to future development. Therefore, the research and industrialization of thin-film high-efficiency solar cells relies heavily on competition and technological accumulation among various technologies to continuously narrow the gap with international advanced levels.
(3) New solar cells
The diffusion junction process limits the improvement of production efficiency and the further reduction of energy consumption. Therefore, the industry is striving to continuously explore new battery materials and manufacturing processes to achieve low cost and high efficiency.
Currently, heterojunction solar cells and high-performance silicon-based flexible thin-film batteries, which utilize the advantages of thin-film manufacturing processes while leveraging the material properties of crystalline and amorphous silicon, are receiving widespread attention and rapid development from researchers around the world.
First, HIT solar cells. HIT cells combine the advantages of amorphous silicon thin-film cells and the high mobility of crystalline silicon, and their fabrication process is relatively simple. The double-sided structure allows for increased light absorption from any angle. However, they still face challenges such as stringent requirements for each step of the production process and significantly higher power generation costs compared to traditional methods. Future development directions include reducing the thickness of the crystalline silicon layer while maintaining cell conversion efficiency, replacing expensive silver paste with inexpensive copper for metal electrodes, and further improving the power generation efficiency of crystalline silicon through technological advancements.
Secondly, high-efficiency flexible silicon-based thin-film batteries. Due to their advantages such as light weight, foldability, portability, and ease of integration, flexible substrate batteries have broad market application prospects. Therefore, more and more research institutes and companies are conducting research on flexible substrate batteries. Currently, important flexible substrate materials include stainless steel, polyimide, plastics, aluminum foil, and polymers. From the perspective of application areas for high-efficiency flexible thin-film batteries, the market is vast and demand is strong, mainly including high-end markets such as aerospace, emerging high-end civilian markets such as luxury car roofs and yacht decks, ground and rooftop power stations, and emergency rescue. Currently, the key technologies for high-efficiency flexible thin-film batteries include: breaking through and mastering the manufacturing technology for the large-scale production of flexible crystalline silicon thin-film batteries, and completing the independent design and manufacturing of production line equipment.
2. Basic Assessment of High-Efficiency Solar Cell Technology
The term "major technology" refers to a technology that occupies a core and crucial position among numerous technologies. Specifically, its importance is measured on three levels: whether it is fundamental, whether it is publicly available, and whether it is strategic.
We believe that major technologies are neither a mechanical addition nor a multiplication of three indicators, but rather a fusion of fundamental, public, and strategic aspects, namely: I (Importance) = B (Basic) × P (Public) + S (Strategic).
The core of the Third Industrial Revolution is the new energy revolution. High-efficiency solar cell technology, as a key to improving solar energy utilization, represents an advanced technological development direction and has a significant impact on the structural adjustment and sustainable development of my country's photovoltaic industry. It is one of the major technologies that should be developed currently, and it is a strategic direction that requires planning and deployment at the national strategic level, with concentrated resources and continuous investment. Therefore, regarding high-efficiency solar cell technology, the question is not "whether to develop it, but how to develop it better."
Basic principles for cultivating major technologies
The purpose of studying major technological and economic policies is to find suitable economic policies based on the characteristics of major technologies in order to promote the progress of major technologies and the enhancement of innovation capabilities, and to realize the transformation of achievements and the great development of industries based on these major technologies.
Given that the market plays a decisive role in resource allocation, what is the role of government departments? What should the government do? What should the government not do? We must effectively combine government guidance and support with the main purpose of enterprises, and achieve a major reform of government function transformation by focusing on the guiding role of major policies.
In terms of cultivating major technologies, the following basic principles should be followed.
1. In terms of functional positioning, the government should both manage less and manage well, and effectively combine government guidance and support with the main purpose of the company.
To truly enable the market to play a decisive role in resource allocation and for the government to better fulfill its functions, companies need a sound market mechanism and development environment—a reasonable and effective market that encourages fair competition, allowing companies to operate freely. Simultaneously, they need to accurately understand what the government is doing, why it is doing it, and how it is doing it, and be able to offer suggestions. Furthermore, companies need to be given back the responsibilities they should bear—that is, to act as the main agents of resource integration, searching for future technological directions and accepting the risks of their choices.
For the government, it is essential to streamline administration and delegate power, entrusting more tasks that it lacks the capacity, conditions, ability, or ability to perform well, such as the selection of major technologies, to the market or society. This would allow qualified social organizations, such as industry associations, to provide these services for a fee, thereby freeing the government from specific tasks, improving the transparency of government services and management, and enabling it to better fulfill its responsibilities in macro-control and supervision.
The government must prevent the administrative allocation of projects and funds, avoiding the practice of "selecting horses" to invest in a few designated companies. Instead, it should define the basic rules for support and the desired final results, allocating funds to the winners through a "horse race." Therefore, the government should support domestic market competition, focusing on supporting the superior and stronger rather than the largest companies.
At the same time, it is essential to change the top-down mindset of government decision-makers and strive to adopt a bottom-up, democratic approach to decision-making. Domestic companies of all types should be encouraged to participate in policy-making, ensuring that relevant government departments understand the true needs of the industry. The "golden megaphone effect"—where policy-making is dictated by large, influential companies while ignoring the voices of smaller businesses—must be prevented. Only in this way can measures and policies be more targeted, and government departments gain greater acceptance from the industry.
In addition, the government must continuously strengthen in-process and post-process supervision to truly achieve "planning beforehand and evaluation afterward," and strengthen the punishment of those who break their promises by establishing a "blacklist" system; clarify the time frame and exit conditions of support policies, and make it clear that the purpose of implementing temporary and conditional protection is to enable companies to have the technical capabilities to be self-reliant and to fundamentally get rid of the situation of being controlled by others.
2. In terms of governance, the government's guidance on major technological development directions should be broad rather than detailed.
The principle of "planning one generation, researching one generation, and industrializing one generation" should be followed, supporting rather than directing major technologies and their development directions. In other words, the government should support the research and development and industrialization of all types of high-efficiency solar cell technologies, rather than choosing and determining specific technology directions on behalf of companies; at the same time, it should prevent companies from monopolizing and hijacking government research resources.
On the one hand, the government should set medium- and long-term technology development and application goals based on extensive consultation with industry. This can not only serve as a basis for selecting major technological directions but also as a "shared vision" guiding all sectors of society to concentrate resources and invest in relevant areas. Furthermore, due to the special status of government departments, their opinions are easily amplified and misinterpreted by industry, leading to unnecessary misunderstandings. Therefore, the government should fully utilize the role of professional industry associations as links and bridges for coordination and communication.
On the other hand, due to information asymmetry, governments find it difficult to obtain accurate and timely information on technological developments. Moreover, with the increasingly rapid pace of technological updates, predicting future technological directions is a laborious and thankless task, and may even be an "impossible mission." Therefore, what governments need to do is create a favorable market environment by improving services and efficiency through institutional arrangements and policy refinements, helping and guiding companies to grasp information and trends in a timely and accurate manner, enabling them to play a leading role in market competition.
Meanwhile, to effectively utilize government funding, government support must be guided by the healthy and sustainable development of the industry, focusing on addressing bottlenecks such as key equipment and materials that hinder the improvement of the industry's core competitiveness during major technological developments, and providing key support accordingly. In the field of high-efficiency solar cells, whether it's crystalline silicon cells, thin-film cells, or new types of cells, they are merely technical means for the photovoltaic industry to reduce costs and improve conversion efficiency.
Furthermore, in allocating government research funds, the focus should be on providing timely assistance rather than simply adding to existing resources, supporting the research funding needs of small and micro-sized companies with strong professional expertise. At the same time, efforts should be made to prevent companies from monopolizing and hijacking government research resources, and to prevent some industry leaders from using their good relationships and influence with relevant government departments to exclude competitors and "pull strings" to obtain limited research investment.
3. In terms of strategy and approach, government support should be "focused" on companies and involve long-term, continuous investment.
The government should prioritize supporting companies, highlighting their primary applications, and provide sustained, long-term support, while also strengthening industry-academia-research collaboration between companies, research institutes, and universities. Given the characteristics of innovation entities—including autonomous decision-making power over innovation activities, the necessary basic capabilities for innovation, the responsibility and risk of innovation activities, and the right to reap the benefits of innovation—companies are more efficient operating entities than research institutes and universities. Furthermore, effective industrial R&D generally requires maintaining good communication channels with companies, as companies are both the source of problems and the end users of R&D results.
Therefore, on the one hand, the government needs to integrate special funds from multiple departments, eliminate phenomena such as multiple applications for the same topic and duplicate funding, strengthen fund supervision, and concentrate financial resources to support the research and development and industrialization of "major technologies" in the photovoltaic field, primarily driven by companies. On the other hand, the government must also adjust the support conditions to ensure that support funds are more focused on core projects and key companies with a certain influence and independent brands, in order to prevent scattered support. At the same time, given the long-term and cumulative nature of research in major technologies, it is essential to provide long-term, continuous, and rolling funding for companies' research projects.
Clarify the specific policies of the reform
After clarifying the principles of development, we also need to clarify the specific policies for reform to prevent falling into "reform fatigue." Of course, specific policies should start with "the areas that the masses most expect to be reformed." At the same time, feasible policies should also be based on fully considering the actual interests of various interest groups to prevent excessive resistance to reform from making it difficult to implement.
1. In terms of demand management, emphasis should be placed on the cultivation and development of "seed users (demonstration households)".
To effectively leverage the decisive role of the market in resource allocation, it is essential to cultivate the market proactively, focusing on long-term interests, transforming potential demand into actual demand, and thereby promoting the healthy development of the photovoltaic industry. Regarding high-efficiency solar cell technology, from a technological innovation perspective, the focus is on continuously improving conversion efficiency and gradually reducing costs. However, to truly promote the healthy development of the solar energy market, high-efficiency solar cell technology must demonstrate practical utility, making people's production and lifestyles more convenient and efficient.
In the early stages of industry development, and at the opportune moment when distributed photovoltaic (PV) power generation applications are receiving favorable policies, cultivating and developing "seed users" to explore innovative application models, and driving mass adoption to truly realize the promising future of distributed PV power generation, ultimately leading to industry development, is crucial for both technological and industrial advancement. "Seed users" are those who initially use and highly value high-efficiency solar cell products, and who can guide mass adoption of these products.
In the field of high-efficiency solar cells, it is essential to target high-potential groups who have a demonstrative, influential, and authoritative influence on the general public, and leverage insights into these groups to enhance customer experience. Furthermore, it is crucial to select appropriate sectors and regions, capitalize on the influence of high-potential areas and sectors, and follow the trend to gradually expand the domestic market.
At the same time, the government can seek to leverage high-end markets with demand primarily driven by applications such as aerospace, unmanned ships, and drones, as well as specialized applications in the civilian sector such as photovoltaic air conditioning, photovoltaic carports, and photovoltaic curtain walls, to encourage the improvement of related technological capabilities by tapping into potential demand and exploring new markets.
Furthermore, to prevent quality decline caused by vicious competition in the current context of overproduction, and to ensure the long-term safety and reliability of products and equipment, as well as better integration with other developed countries, it is necessary to continue to establish and improve the technical standards, testing and certification system for raw materials and products in the solar photovoltaic industry. This will guarantee the quality of raw materials and final products such as polysilicon, photovoltaic modules, and photovoltaic power plants, regulate and guide the healthy development of the industry, and provide market space for the development of advanced technologies.
2. In key technologies and processes, as well as major critical equipment, we should gradually improve our domestic technological capabilities and expand our market share.
The market for critical equipment is not a completely free and competitive market; it has a strong path dependency, and the accumulation of local technological capabilities is crucial. Without national-level support for critical equipment, it is difficult for local companies to improve their technological capabilities and capture the market through continuous modification, improvement, and innovation, relying solely on their own development.
Therefore, it is necessary to implement a localization policy for imported complete sets of key equipment and key technologies in the early stages of industrialization, taking into account the actual situation of industrial development. This involves innovative development through the decomposition and research of imported technologies and key equipment. At the same time, it is necessary to gradually reduce the import of complete sets of key equipment and focus on importing technology patents, technical information, and basic scientific research results.
The government can encourage domestic companies to enter the market and compete through preferential loans, tax cuts, the establishment of special industrial consortia, discounts on public fees, increased import tariffs, and other indirect measures, striving to acquire production processes and technologies with independent intellectual property rights and enhance my country's autonomy in choosing technological paths.
Meanwhile, given that professional and specialized industry associations possess characteristics such as service orientation, representativeness, coordination, and self-discipline, their uses should be fully utilized. By establishing a public social platform (joint innovation center) with engineering and industrialization research as the core, the aggregation of innovation resources and the sharing of innovation achievements can be further realized.
While enhancing the overall technological capabilities of the industry, we will strengthen the industry's voice in setting standards and its initiative in international patent negotiations. Companies are encouraged to participate voluntarily; all results and intellectual property rights acquired will belong to the platform, and participating companies will have priority in using them.
Even with improved domestic technological capabilities, companies often face the challenge of translating technological advantages into market competitiveness. To some extent, marketization barriers on the demand side for key technologies and critical equipment may be far greater than technological R&D barriers on the supply side. Therefore, it is crucial to promote cooperation across the entire industry chain, recognize user participation and interaction in innovation activities, further improve and implement relevant policies such as those supporting the "first-of-its-kind" equipment, establish a risk compensation mechanism for using domestically produced first-of-its-kind products, and enhance policy transparency so that companies and users have a comprehensive understanding of the policies.
3. In terms of technology supply, necessary changes should be made to the way major technologies are supported and international competitiveness is enhanced.
It should be said that specific science and technology systems can enable some countries to operate efficiently and achieve significant breakthroughs at a level close to their knowledge and technology frontiers, while causing most countries to operate inefficiently and become locked into a low-end market, far below the potential level of their knowledge and technology. Meanwhile, the crucial question for technology followers is not "how much to invest in R&D?" but rather "what kind of R&D to conduct?" Therefore, the important issue we currently face is how to use limited support funds effectively, focusing on "effectiveness and efficiency."
To some extent, reforming the way government research funding is organized is an effective way to ensure that funding support is "effective and efficient." We believe that the government must withdraw from the role of evaluating, pricing, and selecting research projects; we can learn from the mature experiences of developed countries and establish special committees for the evaluation and promotion of major technologies. These committees, based on specific technology evaluation concepts and methods, form the foundation for major technology evaluation and are also an important component of the major technology economic policy and decision-making support system.
The assessment and promotion of major technologies encompasses evaluating the attributes of the target technology, its potential economic effects, its impact on future social development, and the specific steps taken to advance the research and industrialization of these technologies. The aim is to promote scientific and democratic decision-making, improve decision-making information and intellectual support systems, and achieve effective and efficient government guidance. To fully utilize the committee system and ensure it truly becomes a powerful organization for selecting and nurturing major technologies and consistently fulfills its purpose, it is essential to strengthen the committee's function while ensuring open processes, clear details, transparent operations, and acceptance of oversight.
