Selection Of Grid Connected Power Generation System

After the implementation of the grid connected power generation system project, it begins to enter the design and implementation phase. The design of the grid connected power generation system puts forward higher requirements for cost control. Currently, there are two methods for the cost and efficiency of the grid connected power generation system. One is an efficient modular production line that uses high-power components to reduce support and labor costs; Another option is to overwire modules, increase the ratio between modules and inverters, maximize inverter output, and reduce the cost of inverters, AC cables, distribution cabinets, and step-up transformers. Both options have their own advantages, but they are not certain and need to be considered comprehensively, carefully calculated, and found an economic balance point. Grid connected photovoltaic power generation, if the same power component and other conditions are the same, the power generation is similar, But if the same number of modules are installed in the same area, using inefficient 250W or efficient 3W, the upfront costs of brackets, foundations, cables, labor, etc. in the system are the same. Therefore, the average unit investment of effective modules will be lower than the average individual investment of ineffective components. In addition to initial costs, efficient components can also reduce land costs.

With the improvement of battery efficiency, the requirements for material quality, performance, equipment accuracy, and technology for grid connected photovoltaic power generation are greatly increased, which will inevitably increase manufacturing costs. Therefore, the cost of high-efficiency modules is higher than that of traditional modules. In order to clarify the impact of high-efficiency module technology on the cost of electricity per kilowatt hour, the sensitivity of power gain and module cost changes to kilowatt hour cost was measured.

Principles of Grid Connected Power Generation System

If light is irradiated on a solar cell, it is absorbed at the interface layer, and photons with sufficient energy can excite electrons from the covalent bonds in P-type silicon and N-type silicon. Before recombination, electrons and holes near the interface will be separated by the electric field of space charge, and electrons will move to the positively charged N region, while holes will move to the negatively charged P region.

Through the charge separation of the interface layer, an outward measurable voltage is generated between the P and N regions. At this time, electrodes can be added on both sides of the silicon wafer and connected to a voltmeter. For crystalline silicon solar cells, the typical open circuit voltage is 0.5-0.6V. The more electron hole pairs are generated by light in the interface layer, the greater the current, and the more light energy is absorbed by the interface layer, resulting in a larger area of the interface layer, i.e. the battery, The greater the current generated in solar cells.

There are two ways for grid connected power generation systems, one is photothermal conversion and the other is direct photoelectric conversion.