MC4 Junction Box——Power Station “Supporting Role”

        China’s newly installed photovoltaic capacity has ranked first in the world for six consecutive years, and costs have continued to fall as the scale continues to expand. Parity Internet access is gradually approaching. In the “low profit era”, refined management of power stations has become the consensus of the industry. In addition to the “protagonists” such as photovoltaic modules and photovoltaic inverters, the role of MC4 connectors and MC4 junction boxes cannot be ignored.

        MC4 junction boxes are small parts in photovoltaic power stations. The current market price is about 20-25 yuan/piece, which only accounts for about 2.7% of the cost of photovoltaic modules, and accounts for less than 1% of the entire power station system. It is such a small component, but it plays a major role in the safety of photovoltaic power plants. If there is a problem with product quality, the power station will face huge risks.

        An industry is a world, and a small junction box is also the epitome of the photovoltaic industry. After the baptism of “price war” and “technical iteration”, where will the mc4 junction box industry go in the future?

The “Bodyguard” of Photovoltaic Modules

        The mc4 junction box mainly has two functions: the basic function is to connect the photovoltaic module and the load, and to export the electrical energy generated by the photovoltaic module through the cable. The additional function is to protect the components, which acts as a bypass protection when the hot spot effect occurs. Therefore, the photovoltaic junction box is also called the bodyguard of photovoltaic modules.

        However, the survey shows that in all power station faults and accidents, the accidents caused by junction boxes and connectors accounted for more than 30%, and the breakdown of mc4 junction box diodes accounted for more than 65% of junction box and connector accidents. Areas with a high incidence of faults. This has also attracted some users’ complaints about the quality of the junction box.

        Wang Yu, executive deputy general manager of Zhejiang Fosalang Energy Co., Ltd., who has focused on the mc4 junction box industry for many years, believes that most users have misunderstandings about junction boxes. The diode is an important part of the junction box. Generally, the diode is in the off state, and the diode will be turned on only when the component has a hot spot.

        Wang Yu further explained that in the construction of photovoltaic modules, a single cell works in series. Once one of the battery slices is blocked, the affected battery will no longer work as a power source, but will become an energy consumer. The other unblocked batteries will continue to pass current through them, causing high energy loss, and “hot spots” will occur. appear. When the hot spot effect reaches a certain level, it will reduce the power output of the components and even cause the components to be scrapped, seriously reducing the service life of the components, and causing hidden dangers to the power generation safety of the power station.

        To avoid this problem, bypass diodes are connected in parallel to one or several batteries connected in series. The bypass current will bypass the shaded cell and pass through the diode. So as to ensure that the photovoltaic power station continues to generate electricity. If the diode is overwhelmed and broken down, it “sacrifices” itself to protect the components.

Cost Reduction and Efficiency Enhancement of MC4 Junction Boxes

        ”Reduce costs and increase efficiency” has become the main theme of the photovoltaic industry chain. As far as the small part of the pv junction box is concerned, the key to reducing cost and increasing efficiency lies in its core component-diode.

        The classification of mc4 junction boxes on the market is based on different types, and Fraser uses diodes as the distinction between junction box types and is generally recognized. Wang Yu introduced that the first-generation product was an axial diode, and the second-generation product was a SMD diode, which is also the most widely used type in the current market. The third generation is a module diode, and the fourth generation is an intelligent product.

        Generally speaking, there are two steps to reduce costs and increase efficiency. The first step is to reduce the initial investment. Comparing the second-generation and third-generation mc4 junction box products, the SMD diode junction box is composed of three diodes and 4 copper sheets, while the module diode is composed of a single module, which reduces material costs and manual welding costs. With the expansion of production scale, the cost advantage of third-generation products will become more prominent.

        After the cost has gradually bottomed out, deliberate subtraction to reduce the cost will cause damage to the 25-year operation of the photovoltaic power station. At this time, more companies are beginning to take the road of “increasing efficiency” and develop new products through technological innovation. Although the initial cost is increased, the cost of electricity can be reduced by increasing the power generation capacity in the later stage.

        The fourth-generation smart mc4 junction box product of Fusalang is the secret weapon of “increasing efficiency”. According to Wang Yu, the smart junction box product has an internal smart chip that can monitor the operating status of each component, meet the requirements of component-level monitoring, find problems early, reduce power generation loss, and increase power generation overall. When the increased power generation offsets or even exceeds the initial cost, economies of scale will be apparent.

        With the continuous development of photovoltaic intelligence, smart junction boxes will be the general trend of the future development of mc4 junction boxes. After 2020, smart grid-based energy Internet junction box products will usher in development.

The Brand Effect of the Junction Box Appears

        Homogeneous low-price competition seems to be the only way for the development of all walks of life in our country. The same is true in the photovoltaic industry. Whether it is photovoltaic modules, photovoltaic inverters or stents, product homogeneity has become a common phenomenon, and the subdivision of photovoltaic junction boxes is no exception.

        According to Wang Yu’s recollection, in 2007-2008, the price of the German brand mc4 junction box was about 200 yuan, which was a momentary glory. It is precisely because of the temptation of huge market segments and low technology thresholds that Chinese small and medium-sized enterprises are swarming to seize the market. In 2011, there were more than 100 companies on the market, and it has surged to more than 200 subsequently. It is accompanied by low-price competition. In 2009, the price of photovoltaic junction boxes was about 100-150 yuan. By 2011, the price had dropped to about 50 yuan. In 2013, the price of junction boxes fell to 30-40 yuan. It drops to about 20 yuan.

        When homogeneous low-price competition reaches a certain level, shuffling is inevitable. In the past few years, the photovoltaic industry encountered a cold wave. After the survival of the fittest in the market, some companies gradually lost their competitiveness and withdrew. Some new companies with technology, capital, and channels squeezed into the market and gained a certain share.

        For power station owners, the cost of mc4 junction boxes in photovoltaic power plants is relatively low, and usually functions to meet the design of the power station, and products with guaranteed quality are more popular. This is undoubtedly a strong competitiveness for companies that have been engaged in the production of photovoltaic junction boxes in the early stage and have formed a scale and brand effect.

        It is understood that there are currently less than 100 photovoltaic junction box companies on the market. The big wave of the industry shuffle, showing that the junction box industry is developing in a rational direction. At present, leading companies such as Renhe, Zhonghuan, and Fushalang have emerged in the industry, and the trend of branding has gradually emerged.

        Wang Yu believes that the photovoltaic junction box industry will usher in a reshuffle in the future, and the number of mc4 junction box companies will remain at about 50 by then. These companies are roughly divided into two categories. One type of company has good channels, and the other type of company relies on high-quality products and services to occupy the market.