In today's world, energy issues have become the trigger point for international disputes. Finding safe, clean and economical new energy sources has become an inevitable choice for people to get rid of energy difficulties through technological means. This is no longer a technical issue, but a highland of strategic competition among nations. For example, high-efficiency solar cell technology is such a project that is a major technological breakthrough. What methods should be adopted for such projects to nurture? This is a problem.
At present, China is in the critical period of innovation-driven development, and is facing the challenge of transforming from high-speed growth to scientific development, and faces the challenge of the original division of labor order and role of the “global value chainâ€. In accordance with China's basic national conditions and the international environment it faces, we must select and cultivate major technologies that have a "support" and "lead" role in China's economy and society around the national strategy, and strive to achieve new breakthroughs in order to grasp China's development initiative. The right to enhance China’s international status.
The so-called major technology means that its technical status is at the core and key position in many technologies. The specific measurement mainly includes three levels: one is whether it is basic; the second is whether it is public; the third is whether it is strategic. Major technology is neither a mechanical addition of the three indicators nor a multiplication, but a combination of basic, public and strategic.
At the moment, the core of the third industrial revolution is the new energy revolution. High-efficiency solar cell technology, as the key to improving solar energy utilization, represents an advanced technology development direction and has an important impact on the structural adjustment and sustainable development of China's photovoltaic industry. One of the major technologies that should be developed now. For high-efficiency solar cell technology, we have "not a question of whether or not to develop, but how to make it better."
Development status of high efficiency solar cell technology
In view of the abundant, cheap, safe, non-polluting and freely usable solar energy resources, solar energy utilization is receiving increasing attention from governments and ordinary people. Solar power generation, an important form of solar energy utilization, is a sustainable alternative to energy and has achieved rapid growth in recent years.
According to the type of technology, solar power generation is mainly divided into two types: photovoltaic power generation and photothermal power generation; among them, photovoltaic power generation is a technology that directly converts solar energy into electric energy with solar battery technology as the core. At present, this technology has not yet become popular due to high costs. However, with the continuous improvement of the technical level of solar cells, the enhancement of scale effect and the continuous decline of prices, photovoltaic power generation with high-efficiency solar cell technology as the core will be widely used.
1. High-efficiency solar cell related technical characteristics
The solar cell (SC) has the advantages of durability, cleanliness and flexibility, and it has no pollution and no noise during the conversion process, and can directly provide off-grid power for small appliances and grid-connected power generation. The application prospect is broad.
Solar cells are the core of photovoltaic power generation systems. Their development and manufacturing is the most critical and important part of the photovoltaic industry chain, which will directly affect the popularity and development of solar power generation. Effectively improving the photoelectric conversion efficiency of solar cells, reducing manufacturing and application costs, and achieving power generation stability are key issues that must be solved in the development and manufacture of high-efficiency solar cells.
At present, the photoelectric conversion efficiency of the general solar cell industrialization level is roughly 180.01% for single crystals, 17.3%-178% for polycrystals, and 8%-9% for amorphous silicon films. According to the State Council, the State Council issued the promotion of photovoltaic industry. Several Opinions on Healthy Development clearly stated that the new PV manufacturing project should meet the conversion efficiency of monocrystalline silicon photovoltaic cells not less than 20%, the conversion efficiency of polycrystalline silicon photovoltaic cells not less than 18%, and the conversion efficiency of thin film photovoltaic cells not less than 12%. .
Of course, high-efficiency solar cells are also a concept that changes over time.
A solar cell is a semiconductor device that converts solar energy into electrical energy using the "photovoltaic effect" principle. Its core raw material is a semiconductor material that can release electrons. The battery products are mainly divided into solar cells represented by crystalline silicon cells, and silicon-based films, cadmium telluride (CdTe) batteries, selenium-indium-copper (CuInSe) batteries, cadmium sulfide (CdS) batteries, and copper indium gallium selenide (CIGS). A solar cell represented by a thin film battery such as a battery or a gallium arsenide (GaAs) laminated battery, and a dye-sensitized battery-photoelectrochemical cell (GrÄtzel battery), an organic battery, a multi-junction (band gap-changing) battery, and heat A new type of battery such as a carrier battery and a solar battery represented by a new concept battery.
As of the end of 2013, among the solar cell products, crystalline silicon solar cells (mainly P-type monocrystalline silicon cells and polycrystalline silicon cells) dominated the market with a market share of over 90%; the market share of thin-film batteries was less than 10%; Most of the batteries and new concept batteries are in the laboratory stage or in the pilot stage, and have not yet been industrialized on a large scale.
At present, the global photovoltaic industry is still in the introduction period, and various related technical routes related to high-efficiency solar cells are developing in parallel. Among them, the crystalline silicon high-efficiency solar cell has the advantages of high photoelectric conversion rate, low pollution, stable performance and low attenuation, and mature large-scale manufacturing technology. Therefore, the world's high-efficiency solar cell structure based on crystalline silicon solar cells is a true portrayal of the past few years, and will continue to dominate in the next decade.
However, in terms of large-scale production today, to achieve the above efficiency requirements, we may need to implement PREC/PERT technology from conventional P-type crystalline silicon technology to P-type crystalline silicon and N-type battery technology (including N-type double The transition of the surface, the heterojunction, the back contact, and the heterojunction back contact battery. At the same time, compared with crystalline silicon cells, thin-film batteries can have a large improvement space in terms of photoelectric conversion efficiency, cost and stability. The breakthrough in thin film technology is expected to become a hot spot for the development of high-efficiency solar cells in the future.
Here, we briefly describe the three types of high-efficiency solar cells.
(1) Crystal silicon high efficiency solar cell
The crystalline silicon solar cells mainly include monocrystalline silicon (mono-Si) batteries and polycrystalline silicon (poly-Si) batteries. The manufacturing process is relatively complicated, and its industrial chain includes the industrial chain of photovoltaic systems from siliceous materials (quartzite, quartz sandstone, etc.) - polysilicon - silicon ingots (rods) - silicon wafers - photovoltaic cells. From the technical point of view, crystalline silicon is not the best material, but because it is easy to acquire, smelting technology is compatible with chemical industry and electronics; therefore, crystalline silicon solar cells have become the mainstream technology in the current photovoltaic cell market.
Among them, the theoretical photoelectric conversion efficiency of crystalline silicon cells is 31%, but there are disadvantages of complex and high energy consumption in the process of crystallization and purification of crystalline silicon. Moreover, the conversion efficiency difference between polycrystalline silicon cells and monocrystalline silicon cells is gradually narrowing, and polycrystalline silicon has the advantages of lower manufacturing cost and larger unit output. Therefore, the market share of polycrystalline silicon (and mono-like poly-Si) batteries has gradually surpassed that of monocrystalline silicon cells and has become a mainstream product in the market, and may continue to play a mainstream role in the future. At the same time, due to the gradual decline of the cost of the battery in the system cost, high-efficiency battery components still have advantages in the terminal system.
In general, the technical development direction of crystalline silicon high-efficiency solar cells is low cost, high efficiency, and high stability, including efficiency improvement, cost reduction, and component life improvement. Among them, the improvement of efficiency depends on process improvement, material improvement and battery structure improvement; the cost reduction depends on the decline of existing material cost, process simplification and new material development; component life improvement depends on component packaging materials and Improvements in the packaging process. Therefore, in addition to relying on the expansion of the industrial scale, the development and industrialization of crystalline silicon high-efficiency solar cells may not only depend on the improvement of the process level, but also on the improvement of industrial technologies (including equipment and raw materials), especially The establishment of new structures and new processes.
(2) Thin film high efficiency solar cell
Thin film solar cells are deposited on glass, plastic, stainless steel and other substrates to form a thin photosensitive material for photoelectric conversion, mainly including non-microcrystalline silicon thin film batteries, cadmium telluride (CdTe) thin film batteries, gallium arsenide (GaAs). Thin film batteries and copper indium selenide/copper indium gallium selenide (CIS/CIGS) thin film batteries.
Among them, the non-/microcrystalline silicon thin film battery has the lowest photoelectric conversion efficiency, generally 6%-9%, and the raw material is silane, which is the easiest to obtain. The photoelectric conversion efficiency of CdTe thin film battery is second, about 8%-11%. The photoelectric conversion efficiency of CIS/GIGS thin film battery is relatively high, about 10%-12%, and the raw material contains rare element compound indium, gallium, selenium. The reserves are small and difficult to obtain. In addition, how to ensure the strict uniform ratio of multi-element is still a major challenge in large-area battery preparation applications.
The GaAs thin film battery has the highest photoelectric conversion efficiency, about 20%-30%. The raw material contains rare element compound gallium, which is small in storage and difficult to obtain. Arsenic is toxic and pollutes the environment. In comparison, CIS/GIGS thin-film batteries are one of the most promising photovoltaic cells in the future due to their low cost, stable performance and strong radiation resistance.
In general, the technical development direction of thin-film high-efficiency solar cells is also low-cost, high-efficiency, high-stability, and the future development prospects are huge. Among them, the continuous improvement of production processes to achieve cost reduction may be the key to future development. Therefore, the research and development and industrialization of thin-film high-efficiency solar cells rely more on the competition and technology accumulation among various technologies to achieve the gap between the international standard and the international advanced level.
(3) New solar cells
The 900 ° C diffusion diffusion process limits the improvement of production efficiency and the further reduction of energy consumption. Therefore, it is the industry's efforts to continuously explore new battery materials and manufacturing process technologies to achieve low cost and high efficiency.
At present, it not only utilizes the advantages of thin film manufacturing process, but also exerts the material properties of crystalline silicon and amorphous silicon. The high-efficiency and low-cost heterojunction solar cells and high-performance silicon-based flexible thin-film batteries are especially popular among researchers in various countries. Pay attention to and develop rapidly.
First, HIT solar cells. The HIT battery concentrates on the advantages of high mobility of amorphous silicon thin film cells and crystalline silicon, and the preparation process is relatively simple. The double-sided structure can increase light absorption at any angle, but there are still strict requirements for each step in the production process. The cost of power generation is still much higher than the cost of power generation by traditional methods. Its future development direction is mainly to reduce the thickness of crystalline silicon under the premise of ensuring the efficiency of battery conversion, and to replace the expensive metal silver paste with cheap metal copper material to make metal electrodes, or to further improve the power generation efficiency of crystalline silicon through technology development. .
Second, a highly efficient flexible silicon-based thin film battery. Since the flexible substrate battery has the advantages of light weight, foldability, portability and easy integration, and has broad market application prospects, more and more research institutes and companies conduct research on flexible substrate batteries. At present, flexible substrate materials mainly include stainless steel, polyimide, plastic, aluminum foil and polymer. From the application field of high-efficiency flexible thin film battery, the market is broad and demand is strong, mainly including high-end market mainly for aviation, aerospace and military, high-end automobile roof, yacht surface and other civil emerging high-end market, ground and roof power station and emergency Rescue and other aspects. At present, the key technologies of high-efficiency flexible thin-film batteries mainly include: breaking through and mastering the manufacturing technology of large-scale production of flexible crystalline silicon thin-film batteries, and completing the independent design and manufacture of production line equipment.
2. Basic assessment of high efficiency solar cell technology
The so-called major technology means that its technical status is at the core and key position in many technologies. The specific measurement mainly includes three levels, one is whether it is basic, the second is whether it is public, and the third is whether it is strategic.
We believe that major technology is neither a mechanical addition of three indicators nor a multiplication, but a combination of basic, public and strategic, namely: I (Importance) = B (Basic, basic) ×P (Public, public) + S (Strategic, strategic).
The core of the third industrial revolution is the new energy revolution. High-efficiency solar cell technology is the key to improving the utilization rate of solar energy. It represents the advanced technology development direction and has an important impact on the structural adjustment and sustainable development of China's photovoltaic industry. One of the major technologies for development is the need to plan and deploy from the national strategic level, focus on resources, and continue to invest in the strategic direction. Therefore, for high-efficiency solar cell technology, we "do not want to develop problems, but how to make them better developed."
Basic principles for nurturing major technologies
The study of major technical and economic policies aims to find suitable economic policies based on the characteristics of major technologies, to promote the advancement of major technologies and the enhancement of innovation capabilities, and to achieve the transformation of results and the development of the industry relying on this major technology.
What is the role of the government sector in the context of the market's decisive role in resource allocation? What is done by the government? What do you want the government to do? It is necessary to effectively combine the government's guiding support with the role of the main body of the enterprise, and achieve a major reform of the transformation of government functions by grasping the guiding role of major policies.
In terms of nurturing major technologies, the following basic principles should be followed.
1. In terms of functional orientation, the government must manage less and manage well, and effectively combine government guidance and support with the role of the enterprise.
To truly realize the decisive role of the market in resource allocation and better play the role of the government, what is needed for enterprises is a good market mechanism and development environment, that is, a reasonable and effective market that encourages fair competition, so that enterprises can Free to play. At the same time, you can accurately understand what the government is doing, why, and how to do it. It is necessary to give advice to the enterprise, that is, to let the enterprise as the main body of resource integration, search for the future technical direction, and accept the choice. risks of.
For the government, it is necessary to simplify the administration of power, and to give more important things, such as the choice of major technologies, to the market or society, such as industry associations, which are incapable, unconditional, untenable, and unsatisfactory. The social organizations are provided with compensation, freeing the government from specific issues, improving the transparency of government service management and better shouldering the functions of macro-control and supervision.
The government must avoid administrativeization of projects and sub-funds, instead of investing funds in certain designated enterprises through “Somaâ€; instead, it determines the basic rules of support and the final effects to be achieved, and distributes the funds to the winners through “horse racingâ€. By. Therefore, the government should support competition in the domestic market, and the focus of support is to support and strengthen rather than support the university.
At the same time, it is necessary to change the top-down thinking mode of government policy makers, and strive to adopt a bottom-up approach to democratic participation in decision-making. All types of domestic enterprises should be encouraged to participate in the formulation of policies. The relevant government departments should be aware of the real needs of the industry and prevent the “golden horn effectâ€, that is, the formulation of policies should be dominated by large enterprises with the right to speak. The voice of a small business. In this way, the measures and policies introduced will be more targeted, and the relevant government departments will be more recognized by the industry.
In addition, the government must continue to strengthen supervision during and after the event, truly “pre-planning and post-assessmentâ€, and strengthen the punishment of the untrustworthy through the establishment of a “blacklist†system; clear time and withdrawal of support policies The conditions must be clearly defined as temporary and conditional protection in order to enable enterprises to have the technical ability 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 the direction of major technological development should be coarse and not fine.
In line with the principle of “layout generation, research generation, industrialization generationâ€, we should support rather than direct major technologies and their development direction, that is, the government should support the research and development and industrialization of all types of high-efficiency solar cell technology, instead of replacing enterprises. Determine the specific technical direction; at the same time avoid corporate monopoly and kidnap government scientific research resources.
On the one hand, the government should set medium- and long-term technological development and application targets on the basis of extensive solicitation of industrial circles. It can not only become the basis for major technological choices, but also serve as a “common vision†to guide the community to gather and invest resources. Go to the relevant direction of the relevant field. In addition, because of the special status of government departments, relevant opinions are easily interpreted by the industry and cause unnecessary misunderstanding. Therefore, the characteristics of professional industry associations and bridges should be fully utilized for coordination and communication.
On the other hand, subject to information asymmetry, it is difficult for the government to correctly and timely learn the dynamic information of technological development, and because the technology update speed is getting faster and faster, predicting the specific technical direction of the future is even more unrewarding, and more It may be an "impossible task." Therefore, for the government, what is needed is to create a favorable market environment. Through some institutional arrangements and policy improvement, improve services, improve efficiency, help and guide enterprises to grasp information and trends in a timely and accurate manner, and let enterprises compete in the market. Play a leading role.
At the same time, in order to effectively play the role of government funds, the government's support must be guided by the healthy and sustainable development of the industry, and respond to bottlenecks such as key equipment and key materials that restrict the improvement of the core competitiveness of the industry in the process of major technological development. In the field of high-efficiency solar cells, whether it is a crystalline silicon battery, a thin film battery or a new type of battery, it is only a technical means for the photovoltaic industry to achieve cost reduction and conversion efficiency.
In addition, in the allocation of government research funds, it is necessary to “send the charcoal in the snow†instead of “adding flowers to the icing on the cake†to support the demand for scientific research funds of professional and small micro-enterprises; at the same time, avoid corporate monopoly and kidnap government scientific research resources, and try to avoid the help of some leading enterprises in the industry. Good relations with the relevant government departments and their influence, and through the exclusion of competitors, "study" to obtain limited scientific research investment.
3. In terms of strategic approach, government support should “focus†on the company and continue to invest in the long term.
The government should focus its support on enterprises and highlight the leading role of enterprises. At the same time, it needs sustained and long-term support, and strengthens cooperation between enterprises, research institutes and universities. In view of the fact that the innovation subject should have the decision-making power of independent innovation activities, the basic ability necessary to carry out innovation activities, the responsibility and risk of undertaking innovation activities, and the income from acquiring innovative activities, compared with research institutes and universities, Businesses are the mainstay of operations more efficiently. Moreover, effective industrial R&D generally requires good communication channels with companies because they are the source of problems and the end users of R&D results.
Therefore, on the one hand, the government needs to integrate a number of special funds for government affairs, eliminate the phenomenon of over-reporting and repeated subsidies, strengthen fund supervision, and concentrate financial resources to support the “major technology†research and development and industrialization of the photovoltaic industry. On the other hand, the government must also adjust the support conditions to make the support funds more focused on core projects and key enterprises with certain influence and independent brands to avoid the scattered support of pepper. At the same time, in view of the long-term and cumulative nature of research in view of the characteristics of major technologies, it is necessary to provide long-term continuous rolling funding for research projects of enterprises in terms of funding allocation.
Clarify specific policies for reform
After clarifying the principles of cultivation, we also need to clarify the specific policies of reform in order to prevent falling into "reform fatigue." Of course, specific policies should be reformed from the "most expected areas of the masses." At the same time, feasible policies should be based on full consideration of the real interests of various interest groups, in order to prevent the reform resistance from being too large to be implemented.
1. In the demand management, we should pay attention to the cultivation and development of “seed users (model households)â€.
To effectively play the decisive role of market allocation resources, we must actively cultivate the market based on long-term interests, change potential demand into actual demand, and promote the sound development of the photovoltaic industry. For high-efficiency solar cell technology, from the perspective of technological innovation, it is mainly focused on the increasing conversion efficiency and the cost reduction year by year. To truly promote the healthy development of the solar market, it is necessary to make the high-efficiency solar cell technology have practical effects. People's production and lifestyle are more convenient and effective.
In the early stage of industrial development, and the best opportunity for distributed photovoltaic power generation applications to welcome favorable policies, how to cultivate and develop “seed users†to explore application innovation models, and to drive the masses of users to truly realize the prospect of distributed photovoltaic power generation, and then Ultimately, the development of the industry has become the key to technological development and industrial development. The so-called "seed users" are those who are initially used and highly recognized and can guide mass users to actively use high-efficiency solar cell products.
In the field of high-efficiency solar cells, it is necessary to target high-potential people who have exemplary, influence and authority to the general public, and use the insights of high-potential people to enhance the customer experience; select appropriate fields and appropriate areas, with high The influence of potential energy regions and fields will be followed by the trend to gradually expand the domestic demand market.
At the same time, the government can seek to use high-end markets such as aviation, aerospace, unmanned vehicles, drones and other military applications, as well as special applications such as photovoltaic air conditioners, photovoltaic carports, and photovoltaic curtain walls in the civilian sector. And open up new markets to encourage the improvement of relevant technical capabilities.
In addition, in order to avoid the current overcapacity, the quality caused by the vicious competition of enterprises, to ensure the long-term safety and reliability of products and equipment, and better integration with other countries in the first place, we must continue to establish and improve the technology of raw materials and products of the solar photovoltaic industry. The standard, testing and certification system guarantees the quality of raw materials and final products such as polysilicon, photovoltaic modules, photovoltaic power stations, regulates the healthy development of the industry, and provides market space for the development of advanced technologies.
2. On key technical processes and major key equipment, local technical capabilities should be gradually upgraded to increase market share.
The major key equipment market is not a completely freely competitive market, it has strong path dependence, and it is decisive for accumulating local technical capabilities. If there is no national level support for key equipment, it is difficult to realize technology only by relying on the development of local enterprises. The improvement of capabilities and the purpose of occupying the market through continuous modification, improvement and innovation.
Therefore, it is necessary to implement the localization policy for the introduction of complete sets of key equipment and key technologies for industrialization in the light of the actual situation of industrial development, and to carry out innovative development through the decomposition and development of imported technologies and key equipment. At the same time, it is necessary to gradually reduce the number of key equipment. Introduction, focusing on the introduction of technology patents, technical intelligence and basic scientific research results.
The government can encourage domestic enterprises to enter the market to participate in competition through preferential loans, tax reductions, establishment of special industrial complexes, discounts on public expenses, increase import tariffs and other indirect measures, and strive to obtain production technology and technology with independent intellectual property rights, and strengthen China. Autonomy in the choice of technology paths.
At the same time, in view of the characteristics of service, representation, coordination and self-discipline of professional and specialized industry associations, it is necessary to give full play to the role of industry associations and to engage in engineering, through the establishment of a social public platform (Joint Innovation Center). The core of industrialization research is to further realize the integration of innovation resources and the sharing of innovation results.
On the basis of enhancing the overall technical capabilities of the industry, strengthen the voice of industry standards and the initiative of foreign patent negotiations. Encourage enterprises to participate voluntarily, achieve results, and intellectual property rights are owned by the platform. Participating enterprises have priority to use.
Even if local technological capabilities are improved, they often face the dilemma of turning technological advantages into market capabilities. To a certain extent, the marketization barriers of key technology processes and major critical equipment on the demand side may be much higher than the technical development obstacles on the supply side. Therefore, it is necessary to promote cooperation in all aspects of the industrial chain, recognize the participation and interaction of users in innovation activities, further improve and implement the “first set†support and other related policies, and establish a risk compensation mechanism using the first domestically produced products. Strengthen the transparency of policies and let enterprises and users understand the policy in all aspects.
3. In the supply of technology, the necessary changes should be made in a way that supports major technologies and enhances international competitiveness.
It should be said that certain science and technology systems can enable some countries to operate efficiently and make major breakthroughs at the cutting edge of their knowledge and technology level, leaving most countries inefficiently operating at locations far below their knowledge and technology levels. Form a low end lock. At the same time, the main question for technical followers is not “how much to invest in R&D?†but “What kind of R&D?†Therefore, the main problem we are currently facing is how to use limited support funds in the cutting edge. Effective, efficient" focus.
To a certain extent, the realization of the reform of the organization of government research funding has become an effective way to achieve financial support “effective and efficientâ€. We believe that the government must withdraw from the role of scientific research project evaluation, pricing, and selection; it can learn from the mature experience of developed countries and set up a special committee for major technology evaluation and promotion. The committee's philosophy and methodology, based on certain technical assessments, is the basis for major technology assessments and an important part of major technology economic policies and decision support systems.
The evaluation and promotion of major technologies mainly include the attributes of the evaluation objects, the possible economic effects, the impact on the future development of the society, and the specific promotion of research and development and industrialization of major technologies. The purpose is to promote the scientific, democratic and perfect decision-making. Decision-making information and intellectual support systems to achieve the government's "effective" and "efficient" guidance. In order to make full use of the committee system and make it truly a power organization that selects and nurtures major technologies and works consistently, it is necessary to strengthen the role of the committee. At the same time, it is open, detailed, transparent, and supervised.
Gloss Vinyl,Yellow Wrap Car,Tesla Nardo Grey,Light Purple Car Wrap
Guangzhou Wanheyan Innovative Materials Co., Ltd. , https://www.wrapremi.com