In-depth Interpretation of BIPV: The Revolution of Architecture and Photovoltaics in a Multi-Billion Dollar Market

With the formal entry into force of the Kyoto Protocol,

how to achieve sustainable environmental protection has become the strongest global call.

As a developing country, China's energy consumption has been growing at an alarming rate year by year,

and buildings, being major energy consumers (in developed countries, building energy consumption generally accounts for more than 1/3 of the national total energy consumption), their energy-saving efficiency has become particularly important, thus BIPV has become a hot spot in the 21st century building and photovoltaic technology market.
 

 

What is BIPV？

 

Building-Integrated Photovoltaics (BIPV) is a technology that integrates solar power generation (photovoltaic) products into buildings. BIPV differs from the form of photovoltaic systems attached to buildings (BAPV: Building Attached PV).
 

 

Depending on the way the photovoltaic array is combined with the building, building-integrated photovoltaics can be divided into two categories: one is the combination of photovoltaic arrays and buildings; the other is the integration of photovoltaic arrays and buildings, such as photovoltaic tile roofs, photovoltaic curtain walls, and photovoltaic skylights. Among these two methods, the combination of photovoltaic arrays and buildings is a commonly used form, especially the combination with building roofs. Because the combination of photovoltaic arrays and buildings does not occupy extra ground space, it is the best installation method for photovoltaic power generation systems to be widely used in cities, and therefore has attracted much attention. The integration of photovoltaic arrays and buildings is an advanced form of BIPV, which has higher requirements for photovoltaic components. Photovoltaic components must not only meet the functional requirements of photovoltaic power generation, but also take into account the basic functional requirements of buildings.

 

BIPV Advantages and Disadvantages

 

Advantages:
 

 

• Green energy. Building-integrated solar photovoltaic systems generate green energy using solar power generation, without polluting the environment. Solar energy is the cleanest and free, and its development and utilization will not produce any ecological side effects. It is also a renewable energy source, inexhaustible and inexhaustible.
• No land occupation. Photovoltaic arrays are generally installed on idle roofs or exterior walls without the need for additional land occupation, which is particularly important for urban buildings where land is expensive; summer is the peak season for electricity consumption, and it is also the season with the highest sunshine and the highest power generation of photovoltaic systems, which can play a peak-regulation role for the power grid.
• Building-integrated solar photovoltaic technology uses grid-connected photovoltaic systems, no batteries are needed which saves investment and is not limited by the state of charge of the battery, allowing full utilization of the electricity generated by the photovoltaic system.
• Plays a role in building energy saving. Photovoltaic arrays absorb solar energy and convert it into electricity, greatly reducing the overall outdoor temperature and reducing the thermal load of the wall and the air conditioning cooling load indoors, so it can also play a role in building energy saving.

 

Disadvantages:

 

• Higher cost Buildings with photovoltaic power generation systems built with integrated design are more expensive, and there is still room for improvement in scientific research and technology.
• High cost The cost of solar power generation is high. The cost of solar power generation is double that of conventional power generation.
• Unstable Solar photovoltaic power generation is unstable and is greatly affected by the weather, with volatility. This is because the sun is not available 24 hours a day, so how to solve the volatility of solar photovoltaic power generation and how to store electricity are urgent problems to be solved.

 

 

BIPV Building Forms

 

It can be said that building-integrated photovoltaics are suitable for most buildings, such as flat roofs, sloped roofs, curtain walls, and canopies.

 
 

Flat Roof From the perspective of power generation, flat roofs are the most economical: 1. They can be installed at the optimal angle to achieve maximum power generation; 2. Standard photovoltaic components can be used, with optimal performance; 3. There is no conflict with the functions of the building. 4. The cost of photovoltaic power generation is the lowest, and it is the best choice from the perspective of power generation economy.

 

Sloped Roof South-facing sloped roofs have good economy: 1. They can be installed at the optimal angle or close to the optimal angle, so maximum or larger power generation can be achieved; 2. Standard photovoltaic components can be used, with good performance and low cost; 3. There is no conflict with the functions of the building. 4. The cost of photovoltaic power generation is the lowest or relatively low, and it is one of the preferred installation schemes for photovoltaic systems. Others (slightly south of south) are secondary.

 

Photovoltaic Curtain Wall Photovoltaic curtain walls must meet BIPV requirements: In addition to power generation, they must meet all the functional requirements of curtain walls: including external maintenance, transparency, mechanics, aesthetics, safety, etc. The component cost is high, and the photovoltaic performance is relatively low; they must be designed, constructed, and installed simultaneously with the building, and the progress of the photovoltaic system project is constrained by the overall progress of the building; the photovoltaic array deviates from the optimal installation angle, and the output power is low; the cost of power generation is high; it enhances the social value of the building and brings the effect of a green concept.

 

 

Photovoltaic Canopy Photovoltaic canopies require transparent components, and the component efficiency is relatively low; in addition to power generation and transparency, the canopy components must meet certain mechanical, aesthetic, and structural connection requirements in terms of building; the component cost is high; the cost of power generation is high; it enhances the social value of the building and brings the effect of a green concept.

BIPV Building Design

 

Photovoltaic Component Performance Requirements As a common photovoltaic component, as long as it passes the IEC61215 test and meets the requirements of resisting 130km/h (2,400Pa) wind pressure and the impact of 25mm diameter hail at 23m/s. Photovoltaic components used as curtain wall panels and skylight panels not only need to meet the performance requirements of photovoltaic components, but also the three-property test requirements of curtain walls and building safety performance requirements, so they need higher mechanical properties and different structural methods. For example, a common photovoltaic component with a size of 1200mm × 530mm generally uses 3.2mm thick tempered ultra-white glass and an aluminum alloy frame to meet the usage requirements. However, components of the same size used in BIPV buildings, in different locations, different floor heights, and different installation methods, may have completely different requirements for their glass mechanical properties. The components used in the external circulating double-layer curtain wall of Nanbo Building are photovoltaic components made of two 6mm thick tempered ultra-white glass laminates, which is the result of rigorous mechanical calculations.

 

 

Aesthetic Requirements BIPV buildings are first and foremost buildings; they are works of art created by architects, comparable to a musician's music or a painter's masterpiece. For a building, light is its soul, therefore buildings have very high requirements for light and shadow. However, the glass used in ordinary photovoltaic components is mostly textured ultra-white tempered glass, and its texture has the effect of blocking the line of sight like frosted glass. If the BIPV component is installed in a sightseeing area of a building, this location requires light transmission, in which case ultra-white tempered glass should be used to make double-sided glass components to meet the function of the building. At the same time, in order to save costs, ordinary smooth tempered glass can be used for the glass on the back of the battery plate. The success or failure of a building depends largely on its appearance; sometimes even minor inconsistencies are unacceptable. However, the junction box of ordinary photovoltaic components is usually glued to the back of the battery plate. The junction box is relatively large and easily disrupts the overall harmony of the building, which is usually unacceptable to architects. Therefore, BIPV buildings require the junction box to be omitted or hidden. In this case, the bypass diode is without the protection of the junction box, so other methods must be considered to protect it. The bypass diode and connecting wires need to be hidden in the curtain wall structure. For example, the bypass diode can be placed in the curtain wall frame structure to prevent direct sunlight and rainwater erosion. The connecting wires of ordinary photovoltaic components are generally exposed below the components. In BIPV buildings, the connecting wires of photovoltaic components are required to be completely hidden in the curtain wall structure.

 

 

Structural Performance Matching When designing BIPV buildings, the voltage and current of the battery panel itself should be considered to facilitate the selection of photovoltaic system equipment. However, the exterior walls of buildings may be composed of geometric shapes of various sizes and forms, which will cause different voltages and currents between components. In this case, it is possible to consider dividing and adjusting the grid of the building facade to make the BIPV components closer to the standard component electrical performance. Different sizes of battery plates can also be used to meet the requirements of the grid, maximizing the effect of the building facade. In addition, a few battery plates on the corners can be left unconnected to the circuit to meet electrical requirements.

 

 

Utilizing Solar Energy Solar energy has created favorable conditions for environmental protection, so many architects cleverly use solar energy to build solar buildings.

 

1. Solar Walls: American building experts have invented solar walls. A thin layer of black perforated aluminum plates is installed on the outer side of the building's wall, which can absorb 80% of the solar energy that shines on the wall. The air drawn into the aluminum plate is preheated and pumped into the building through the pump inside the wall, thereby saving the energy consumption of the central air conditioning.

 

2. Solar Windows: German scientists have invented two types of glass windows using photothermal regulation. One is a solar temperature regulation system that collects warm air from the surface of the building's window glass during the day and then transfers this solar energy to the space storage in the walls and floors, releasing it at night; the other automatically adjusts the amount of sunlight entering the room, like color-changing sunglasses. Depending on the room's set temperature, the window glass becomes either transparent or opaque. 3. Solar Houses: German architect Tholls built a solar house that can rotate on its base to track the sun. The house is installed on a circular disc base, and a small solar electric motor drives a set of gears to allow the house base to rotate on a circular track at a speed of 3 centimeters per minute, following the sun. The power consumed by this sun-tracking system is only 1% of the house's solar power generation capacity, while the house's solar power generation is twice that of a regular non-rotating solar house.
 

BIPV Innovation Experience
 

 

 

 

 

 

BIPV Application Prospects

1. Photovoltaic Application in High-Energy-Consumption Industrial Buildings

 

The "Renewable Energy Electricity Quota and Assessment Measures" states that "all types of power sales companies, power users participating in direct power transactions, and enterprises with self-owned power plants are subject to quota assessment. The quota completion situation is assessed by calculating the number of renewable energy electricity green certificates for each quota obligated entity."

 

 

2. Photovoltaic Application in Slope Modification of Existing Buildings

 

The "State Council Policy Regular Briefing - Urban Old Residential Area Renovation Work" [CCTV reporter] asks Deputy Minister Huang Yan, you just mentioned that one of the difficulties in the renovation of old residential areas is funding. What models can be adopted in the future to use market-oriented methods to support the renovation of old residential areas? [Deputy Minister of Housing and Urban-Rural Development Huang Yan] I went to Guangxi for research last week and also raised this topic to the mayor. Everyone feels that allowing the market to participate more in the renovation of old urban residential areas is an innovation of the mechanism. Using financial support methods, it cannot just be invested without turning around; this is a prerequisite.

 

3. Photovoltaic Application in the Construction of Photovoltaic Villages

 

The "Opinions of the Central Committee of the Communist Party of China and the State Council on Establishing and Improving the System and Policy System for Integrated Urban-Rural Development" states that "adhering to the new development concept, adhering to the promotion of high-quality development, adhering to the priority development of agriculture and rural areas, taking the coordinated promotion of the Rural Revitalization Strategy and the New Urbanization Strategy as the starting point, and aiming to narrow the gap in development and living standards between urban and rural areas, we will accelerate the formation of a new urban-rural relationship of mutual promotion between industry and agriculture, mutual supplementation between urban and rural areas, comprehensive integration, and common prosperity, and accelerate the advancement of agricultural and rural modernization."

Original text remains as is

 

 

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Figure 1: Classification of Photovoltaic Power Plants

 

Building-integrated photovoltaics (BIPV) belongs to distributed photovoltaics. Compared with centralized photovoltaic power plants, it has advantages such as land saving, local consumption, and peak power regulation. Building-integrated photovoltaics combines photovoltaic power generation with buildings, laying photovoltaic devices on the outer periphery of the building structure to generate electricity.

 

Building-integrated photovoltaics is divided into two categories:

1. BAPV, installed photovoltaics, Building attached photovoltaics, the photovoltaic system is attached to the surface of the building.

2. BIPV, building-integrated photovoltaic, Building integrated Photovoltaic, the photovoltaic system becomes a direct building material.

 

BAPV is a simple integration method suitable for retrofitting existing roofs. Additional steel structural supports or rails are installed directly on the building's roof, and photovoltaic panels are fixed for power generation. Currently, the "county-wide promotion" of photovoltaic roofs all use this method.

Figure 2: Typical application of BAPV

 

The main problems encountered by BAPV are:

1. Load. The load of the original roof does not meet the requirements for secondary installation of photovoltaic panels, and the original roof needs to be reinforced. Some reinforcement is difficult. There have even been news reports of roofs collapsing under snow and photovoltaic panels being blown away by strong winds.

2. Waterproofing. BAPV will damage the original roof waterproofing layer, and repairs are needed after construction, leading to drainage problems.

3. Safety and actual service life of photovoltaic panels. Ancillary components such as inverters and junction boxes are often exposed, affecting aesthetics and easily damaged, reducing the actual service life of BAPV.

 

BAPV is often a project that requires a one-time investment with returns over many years, and owners value the rate of return and safety. Once a major loss occurs, there may be difficulties in effectively protecting rights and interests. BIPV, building-integrated photovoltaics, can avoid many of the problems of BAPV. It has advantages such as long lifespan, reliable load-bearing capacity, reliable waterproofing, and easy operation and maintenance.

 

BIPV Classification and Development


BIPV is where photovoltaic systems become direct building materials. A series of photovoltaic building materials have been developed, including photovoltaic roofs, photovoltaic glass, photovoltaic curtain walls, and photovoltaic tiles.

Figure 3: Comparison of BIPV related products and BAPV

 

BIPV It can be divided into crystalline silicon type and thin-film type according to the material.


Crystalline silicon BIPV has high conversion efficiency, with monocrystalline reaching 25%. Crystalline silicon cells are opaque, and crystalline silicon components are mainly used in opaque building projects. Of course, crystalline silicon photovoltaic curtain walls using double-sided glass can also meet certain light transmission requirements. Crystalline silicon is the most familiar type.
Longi Green Energy's "Longding" and "Longjin," JA Solar's "Jingcai," Trina Solar's "Zhiding," Tesla's Solar Roof V1-V3, Jinhua New Energy's "Huading," and Shangmai New Energy's "Jiwa" are all crystalline silicon products.

Figure 4: Opaque crystalline silicon photovoltaic curtain wall at the headquarters of Wuxi Suntech

 

Figure 5: Crystalline silicon photovoltaic curtain wall, showing light transmission effect

 

Thin-film BIPV currently mainly includes cadmium telluride (CdTe) cells, copper indium gallium selenide (CIGS) cells, and perovskite solar cells.
The average efficiency of cadmium telluride in commercial applications is 14.7%. Copper indium gallium selenide cells currently have the highest efficiency among thin-film types, approaching 20%. While the efficiency is lower than crystalline silicon, thin-film also has advantages that crystalline silicon does not: adjustable transparency, better low-light performance, and a better temperature coefficient. This ensures that it can maintain operation under extreme conditions such as high temperature and low light.

Figure 6: Building effect of colored thin-film cells

 

Thin-film cells are not a recent concept. Thin-film cell technology emerged in the 1970s, surpassing crystalline silicon cells for a time and even being called "next-generation photovoltaic technology." Later, due to difficulties in improving efficiency, it gradually faded away.
Now, the explosion of BIPV has brought new opportunities for thin-film cells. Currently, domestic companies in the thin-film field include Longyan Energy, Mingyang Smart's subsidiary Ruike New Energy, and Hangzhou Xianna. However, major players in the photovoltaic industry dominate the crystalline silicon cell market. Currently, the crystalline silicon camp appears more prominent.

 

BIPV According to the product form, it can be divided into building material type and component type.


"Building material type" integration is more complete, fully integrating photovoltaic cells into building materials, and the appearance may not be much different from traditional building materials. It places higher demands on material strength and performance. "Building material type" is a relatively ideal form, but it has a high degree of customization, high strength requirements, and high cost.
Tesla solar roof tiles are of the "building material type." According to Customer Feedback from Musk's first batch of customers, they are suitable for people who are "financially insensitive." You can ponder that.

Figure 7: Little Pony and Tesla Roof

 

"Component type" leans towards standardized products, combining photovoltaic components with building components into integrated components, which are easier to distinguish from traditional building materials in appearance. This is currently the mainstream in the market, mainly photovoltaic roofs, photovoltaic curtain walls, and photovoltaic sunshades. On the one hand, it can maximize the component power generation efficiency and maximize the effective power generation area of the cells. However, standardized components also limit application scenarios, currently mainly used in the large-area roofs of industrial and commercial factory buildings, rainproof carports, and large building exterior curtain walls.
Now, photovoltaic component companies have also launched translucent and colored photovoltaic curtain walls, providing design institutes with more design styles to choose from and meeting certain architectural aesthetic design requirements.

Photovoltaic curtain walls have both photovoltaic and building properties and need to be designed, constructed, and installed simultaneously with the building, resulting in higher costs. In addition to the power generation function, they must meet the building's functional requirements: external maintenance, transparency, mechanics, aesthetics, and safety. Building functional requirements are higher than photovoltaic power generation requirements, and building functional requirements must be prioritized, so sometimes photovoltaic properties may be sacrificed, such as higher power generation efficiency, better light angle, and larger power generation capacity.

Figure 8: Component-type photovoltaic roof, double-sided glass and cells

 

Figure 9: King's Cross Station, London, 2014

 

The photovoltaic roof of King's Cross Station in London, in order to meet the light transmission requirements, shows that the cells are relatively sparse, sacrificing higher wattage and power generation efficiency.

BIPV Three Generations of Technological Development


In summary, the development process of BIPV technology can be summarized as follows:

First generation: Photovoltaic arrays are installed on the surface of buildings with some additional support and fixing devices, similar in appearance to BAPV. Most crystalline silicon BIPV is currently mainstream.

Second generation: Mainly thin-film cells, photovoltaic components and building materials are integrated, with a beautiful appearance. However, power electronic devices and wiring are inconvenient to arrange, reliability is low, and maintenance costs are high.

Third generation, photovoltaic systems, building materials, and power conversion devices are all integrated. High customization requirements and high costs. Needs to develop a new generation of technology and materials.

 

With the further improvement of the economic efficiency of photovoltaic building-related products, photovoltaic buildings will achieve rapid development, contributing to the "carbon neutrality" of the building industry. This article introduces six application cases of photovoltaic buildings using power generation glass building materials for your reference.

 

 

1. Xiong'an Business Service Center

 

The Xiong'an Business Service Center project is located north of the Xiong'an Citizen Service Center. It is a functional area that undertakes the relocation of non-capital functions from Beijing, focusing on business, finance, service outsourcing, and free trade zone-related industries. It aims to create an industrial cluster integrating headquarters economy and technological innovation. After completion, the Xiong'an Business Service Center will, together with the Xiong'an Citizen Service Center, provide comprehensive service support for the construction and development of the Xiong'an New Area.

The convention center will meet the three-star rating standard for green buildings. The project uses high-efficiency electromechanical equipment, including high-efficiency energy-saving transformers and water pumps. Water-saving appliances meet the first-level energy efficiency, lighting uses safe and efficient LED lighting, and an air quality monitoring system that can monitor indoor PM2.5 concentration is set up.

 

The project features the country's first large-scale roof with interspersed design of ceramic tiles and photovoltaic tiles. Traditional ceramic tiles have good heat insulation and heat preservation functions, and solar photovoltaic panels continuously provide clean energy for the building.

 

The combination of frosted photovoltaic tiles and ceramic tiles takes into account both power generation efficiency and the overall architectural effect, while avoiding light pollution caused by reflection.

 

 

The project uses 10,355 cadmium telluride thin-film photovoltaic flat tiles, with an installed capacity of about 486.68 kWp and an annual power generation of over 400,000 kWh, equivalent to a reduction of nearly 400 tons of carbon dioxide emissions per year.

 

 

2. China Pavilion, World Horticultural Exposition

 

The China Pavilion of the 2019 Beijing World Horticultural Exposition is located at the end of the landscape axis of the Mountain and Water Garden in the core landscape area of the Expo. It occupies the most important position in the entire park and is one of the most important buildings of the Expo, forming the core landscape area of the Expo park together with the International Pavilion, the Performing Arts Center, the Lawn Theater, and Tiantian.

The 2019 World Horticultural Exposition, themed "Green Life, Beautiful Home," is divided into five areas: the China Pavilion, the International Pavilion, the Plant Pavilion, the Life Experience Pavilion, and the Performing Arts Center. At the foot of the mountains and by the Gui River, the World Horticultural Exposition is like a green scroll, showcasing a "green business card" to the world.

 

The steel structure roof of the China Pavilion is equipped with 1,024 gold photovoltaic glass panels, which can generate electricity even without direct sunlight, better fitting the architectural shape. The glazed tiles gather solar energy, creating a brilliant picture and lighting up the night of the World Horticultural Exposition.

 

The project uses solar photovoltaic technology and other green technologies to make the China Pavilion a living, breathing building. The project successfully passed the green building label evaluation and obtained the three-star green building label.

 

 

3. Datong Future Energy Pavilion

 

As the most important landmark building in the Datong International Energy Revolution Science and Technology Innovation Park, the Shanxi Datong Future Energy Pavilion undertakes the important strategic functions of comprehensively promoting and displaying the achievements of Shanxi's energy revolution and leading the technological innovation of the energy revolution. It is a comprehensive exhibition hall integrating six pavilions: the Energy Strategic Planning Pavilion, the Energy Civilization Dissemination Pavilion, the Energy Revolution Demonstration Pavilion, the Energy Science Popularization and Education Pavilion, the Energy Life Experience Pavilion, and the Energy Technology Exhibition Pavilion. To embody Shanxi Province's leading image in the global energy development and transformation process, the building itself is also part of the energy revolution demonstration.

 

The Datong Future Energy Exhibition Pavilion achieves the ultra-high-performance building indicators of "Three-Star Green Building + Ultra-Low Energy Consumption Certification + Healthy Building." Under the design concept of "passive priority, active optimization," it utilizes a number of passive technologies, including the outer enclosure structure with excellent thermal insulation performance and high airtightness, high-efficiency energy-saving passive doors and windows curtain walls, summer shading, prevention of thermal bridges, underground wind system, and organized indoor fresh air supply and heat recovery system.

 

The Datong Energy Pavilion maximizes the use of the building's exterior surface, Using building-integrated photovoltaic technology to achieve a photovoltaic power generation capacity of nearly 1 megawatt for the building itself, coupled with DC microgrid technology with energy storage to improve the utilization efficiency of renewable energy, thus achieving the "zero energy consumption" target of building energy consumption, It is the first positive energy building of the exhibition hall type to be implemented nationwide.

 

 

 

4. Jiaxing Railway Station

 

Jiaxing Railway Station was designed by MAD Architects, led by Ma Yansong, and is known as the "Railway Station in the Forest." The renovation and expansion project started on June 23, 2020. The station is designed with one floor above ground and multiple floors underground, making it China's first fully sunken railway station.

More than 1,500 trees, including Zelkova, Cinnamomum camphora, Osmanthus fragrans, maple trees, Sapium sebiferum, Metasequoia glyptostroboides, and cherry blossoms, were planted during the renovation of the railway station. The main spiritual axis based on the old station building runs through the entire project, with Zelkova trees planted on both sides. After the Zelkova trees are fully grown, their crowns will connect to cover the entire north square in front of the station. More than 500 large trees, including Zelkova, Cinnamomum camphora, Osmanthus fragrans, and maple trees, were planted inside and outside the station building, with Zelkova trees being over 30 years old.
 

In addition to being called the "Railway Station in the Forest," Jiaxing Railway Station is also a power-generating "green" railway station. According to statistics, about 12,000 high-efficiency cadmium telluride thin-film photovoltaic building materials were installed on the roofs of the north and south station buildings. After the project is put into operation, the estimated annual power generation is 1.1 million kilowatt-hours, equivalent to a reduction of about 1,000 tons of carbon dioxide emissions per year.

 

 

Jiaxing Railway Station cleverly uses photovoltaic building materials to transform the "fifth facade of the building (building roof)" into an "ecological fifth facade," Not only does it highlight the aesthetic function of the roof, but it is also a bold exploration and attempt of green and clean photovoltaic technology on the building roof, fully highlighting the "green building concept" and providing important reference and demonstration for the construction and renovation of high-speed railway stations, airports, convention centers, shopping malls, and other public building venues in the future.

The renovated Jiaxing Railway Station may bring transformative inspiration to Chinese cities undergoing urban construction. Transcending utilitarianism and functionalism, transforming municipal and public buildings into high-quality humanistic urban spaces will be the next milestone in China's urban development.

 

 

5. Jiaxing Xiuzhou Science and Technology Innovation Service Center

 

The Jiaxing Xiuzhou New District Science and Technology Service Center project is located in Xiuzhou District, Jiaxing, and serves as the new administrative approval service center for Xiuzhou District. Xiuzhou Photovoltaic Town is committed to becoming a leading domestic demonstration area for the large-scale application of distributed photovoltaic power generation, a globally leading photovoltaic computing and R&D innovation area, and a nationally renowned characteristic photovoltaic intelligent manufacturing center, a photovoltaic characteristic town that is "suitable for work, living, tourism, benefiting production, people, and life."

 

 

The photovoltaic curtain wall adopts a modular bright frame and a partial vertical-bright horizontal-hidden combination curtain wall system. The fish-scale area uses cadmium telluride photovoltaic glass. It uses a total of 931 pieces of 40% light-transmitting cadmium telluride thin-film translucent photovoltaic glass in 30 sizes, with the largest size being 1592mm*2185mm, totaling 2013 square meters, with an installed capacity of approximately 150KW. The structure of the photovoltaic glass is: 5TP+3.2CDTE+5TP+12A+8TP.

 

During the design and construction process, the project solved many highly difficult technical problems of photovoltaic curtain walls, such as the strict requirements for the color consistency of photovoltaic glass and LOW_E glass, oversized sizes, photovoltaic glass string design, and hidden wiring design.

 

 

6. Shenzhou International Color Pattern Photovoltaic Curtain Wall

 

The Shenzhou International Color Pattern Photovoltaic Curtain Wall project is located on the side of the factory building of Ningbo Shenzhou International Group Holdings Co., Ltd. This photovoltaic curtain wall project is invested by the State Grid (Ningbo) Integrated Energy Service Co., Ltd. and adopts cadmium telluride thin-film color pattern photovoltaic building materials. It is a model project for green energy-saving renovation of existing buildings.

 

The project adopts a photovoltaic building integrated design and renovates existing factory buildings. It is not only beautiful and fashionable and provides heat insulation, but also brings continuous power generation benefits to the enterprise for more than 25 years.

 

As a trillion-level market, further elaboration on the economic efficiency, potential scale, and trends of the BIPV industry is needed.

 

BIPV is expected to become a new trend in infrastructure construction.

 

BIPV, Building Integrated PV (PV stands for Photovoltaic), is a technology that integrates solar power generation (photovoltaic) products into buildings. It is not a new concept, but rather an application scenario of photovoltaics. Its earliest application can be traced back to satellites and the International Space Station, where the photovoltaic power generation structure on satellites is the earliest prototype of the integration of photovoltaics and structure.

 

From the perspective of BIPV's sub-sectors, it belongs to distributed photovoltaics. Because of its combination with buildings for power generation, it brings huge potential in energy, and therefore has always been much discussed. It is also the most promising distributed photovoltaic system. Similar to it is another branch—BAPV (Building Attached Photovoltaic), which refers to a solar photovoltaic power generation system installed on buildings.

 

Globally and in China, building energy consumption accounts for more than 30% of all industries and is a major source of energy consumption and carbon dioxide emissions.

Photovoltaic energy for buildings can effectively solve this problem, so BIPV is a necessary means to achieve zero-energy buildings. In recent years, With the continuous decline in the cost of photovoltaic components, the era of affordable large-scale applications is approaching, and the economic benefits of BIPV are becoming increasingly prominent.

 

The forms of photovoltaic integration with building materials mainly include integration with roofs, walls, and shading devices. According to the schematic diagram in "Solar Photovoltaic and Building Integrated Construction" edited by Jiangsu Provincial Urban Planning and Design Research Institute, solar power generation systems can be combined with roof structures such as roofs, skylights, curtain walls, balconies, and railings to form green, environmentally friendly, and energy-saving buildings. They can also be combined with building materials to form photovoltaic shading components and photovoltaic awnings, thus achieving the effect of sun shading and rain protection.

Compared to traditional roofs and BAPV, it has stronger reliability and economic efficiency.

 

Reliability: Currently, industrial and commercial factory roofs generally use cement or color-coated steel tiles, with a lifespan of about 10 years. However, the lifespan of BIPV roofs can reach more than 20 years. As for converting roofs to BAPV, because BAPV requires roof modifications, it inevitably causes problems such as roof drilling and edging, leading to damage to the roof structure.

 

Economic Efficiency: Generally speaking, traditional roofs or curtain walls do not generate benefits after construction, while BAPV and BIPV can generate economic benefits by saving energy through power generation. For BIPV, due to its customized nature, it can fully utilize the roof structural area, significantly improving the utilization efficiency of the roof or wall area. Judging from the income situation of the Fujian Production Command Center and Xingye R&D Building, The cost can basically be recovered within 5-8 years, showing significant economic efficiency.

 

Judging from the policy, capital, and project reserve levels this year, the certainty of accelerated infrastructure investment is high, and BIPV is expected to rapidly increase in volume.

 

Market Potential and Trends of BIPV

 

The National Energy Administration's press conference on August 2 stated that in the first half of 22, the newly installed capacity of domestic photovoltaics was 30.88GW, a year-on-year increase of 119%, of which distributed photovoltaics increased by 19.65GW. Looking at distributed photovoltaics alone, household photovoltaics added about 9.5GW, a year-on-year increase of 52%, and commercial and industrial distributed photovoltaics added about 10.7GW, a year-on-year increase of 268%. Distributed photovoltaic installations achieved rapid development in the first half of the year. BIPV is an important component of distributed photovoltaics and is also one of the few areas where the concepts of "dual carbon" and infrastructure construction overlap, with short-term steady growth support.

 

Tianfeng Securities estimates By 2025, the market space for newly built factory-type BIPV is expected to reach 69.3 billion yuan, with a CAGR of +82.8% from 20 to 25.

 

Potential Market for Factory and Warehouse BIPV

 

According to Xingye Securities, in the long term, under the background of "dual carbon", BIPV is an important measure to reduce carbon emissions during building operations and one of the most promising directions in the future. In the long term, the downward trend of infrastructure construction to the county level is obvious, which is expected to accelerate the promotion of "photovoltaic whole-county promotion." The market size is expected to exceed 100 billion yuan in 2025.
 

 

BIPV Market Size Estimation

 

Industry Trend: Strong Joint Efforts Between "Building + Photovoltaic" Enterprises
 

 

BIPV products are mainly composed of photovoltaic components and building structures. The industry chain of photovoltaic components is similar to that of BAPV and centralized photovoltaic power plants, and it is the main link for BIPV product iteration and cost reduction.

 

The core competitiveness of photovoltaic companies lies in the development of BIPV products. They lack experience in building materials and construction, have limited project resources, and lack professional construction qualifications, architectural R&D design, and construction management capabilities. Therefore, it is difficult for them to independently enter the construction market and undertake BIPV construction projects in the short term.
 

 

On the other hand, construction companies possess certain business resources, such as industrial and commercial plants and government investment platforms, which are important links for BIPV docking and implementation. However, the difficulty for construction companies in carrying out BIPV projects lies in the fact that BIPV product development has certain technical barriers. Photovoltaic company products have become increasingly mature, while construction units lack the corresponding resources in photovoltaic component production, etc. If developed independently, the R&D investment cost would be high, and it would be difficult to develop competitive products.

 

Only through equity cooperation or strategic investment to form a deep partnership can construction and photovoltaic companies achieve a "fusion" effect, enabling rapid product volume increase and seizing market opportunities under the backdrop of the rapid expansion of the BIPV industry.