What are the bottlenecks of domestic photovoltaic power generation grid connected?

Access conditions (smart grid, transmission line construction), policies (national, local, industry policies) and other aspects are not to be discussed, briefly talk about the problems of the photovoltaic system itself:

1. Improve the conversion efficiency of components. In the same case, improving the efficiency of components can save land resources and reduce the cost of equipment such as brackets, cables, and combiner boxes. (It can reduce investment costs).

2. Improve the quality of components to the consistency of performance. At present, the grid-connected power stations are all MW-level, and the total quality defects and consistency losses of ordinary modules exceed 5%; (It can improve the efficiency of power generation).

3. Improve the trouble-free operation time of the system. This is primarily determined by the quality of the core components, followed by the system design technology, and then the environmental conditions of the site. (Reduced operation and maintenance costs).

4. Reduce the loss of components, in addition to components, the photovoltaic grid-connected system is also composed of combiner boxes, DC distribution cabinets, inverters, step-up transformers, AC and DC transmission lines, etc., which will produce a certain loss every time it is converted and transmitted.

Rational selection of components can reduce costs and improve system efficiency).

5. Monitoring and communication problems. The communication formats and protocols adopted by the power grid dispatching platform and various equipment manufacturers are different, and there is no unified standard. Just like a mobile phone charger, when buying a mobile phone, you must match the corresponding mobile phone charger, and there is no right to choose.

Get rid of the power grid company, get rid of the obstacle policy, and get rid of the user's doubts and ......

The basic necessary condition for the grid connection of the photovoltaic power generation system is that the frequency and phase of the sine wave current output by the inverter are the same as the frequency and phase of the grid voltage.

In terms of safety, whether the switch of the grid-connected point meets the safety requirements, and whether the safety of the equipment in the event of an abnormal or faulty power grid can be reliably disconnected to ensure personal safety.

1. Photovoltaic power generation has the characteristics of randomness, intermittency and obvious periodicityAt present, it is not accurate** and cannot participate in the power balance into the power generation plan. The consumption of photovoltaic power generation can only be fully purchased by the power grid company after grid connection in accordance with the requirements of the Renewable Energy Law;

2. Photovoltaic power generation only generates electricity during the dayAt night, the radiance is zero, and the output is also zero.

After sunrise, the solar radiation gradually increases, reaching a peak at noon, and the output of the photovoltaic power station also increases with the increase of radiation, and the output is the largest at noon;

3. When the photovoltaic power station has output, other power sources in the power grid need to adjust the outputThe output load is powered by photovoltaic power generation. Affected by the weather, when the output of photovoltaic power generation declines rapidly, other conventional energy sources must provide compensation and adjustment for its active power output to ensure continuous, reliable and safe power supply to the electricity load;

4. Fluctuations in photovoltaic power generationIt is completely random according to weather conditions, much faster than the normal load change of the power grid, and when there are clouds drifting by, the output of the photovoltaic power station can be quickly reduced by up to 70%;

5. Adjustable capacity prepared for photovoltaic power generationIt cannot be completed by temporary start-stop, but is in a rotating standby state. The larger the installed capacity of photovoltaic power generation, the larger the rotating backup for this purpose.

Before installing a photovoltaic power generation system, it is necessary to apply to the local power grid company and file in advance. After the power grid company replies that it can be installed, the whole system including components, brackets, inverter combiner boxes, etc. can be notified to the power grid company for acceptance and issuance of grid-connected meters after the installation is completed according to the standard, and the grid-connected power generation can be done.

Grid-connected power generation systems are divided into solar grid-connected power generation systems and wind grid-connected power generation systems.

The grid-connected solar power generation system is composed of photovoltaic modules (squares) and photovoltaic grid-connected inverter power supply devices. Photovoltaic modules (squares) convert solar energy into direct current energy, and through the grid-connected inverter power supply, the direct current energy is converted into alternating current energy at the same frequency and phase as the grid and fed into the power grid. Grid-connected inverter power supply is the core equipment of photovoltaic grid-connected power generation system.

The wind turbine grid-connected power generation system consists of a wind turbine, a wind turbine controller, a wind turbine grid-connected inverter power supply and a metering device. The wind turbine converts the wind energy into alternating current energy, which is converted into DC electric energy through the fan controller, and the direct current electric energy is converted into alternating current energy at the same frequency and phase with the grid through the wind turbine grid-connected inverter and fed into the power grid. The wind turbine grid-connected inverter power supply is the core control equipment of the wind grid-connected power generation system, which rectifies the alternating current emitted by the wind turbine into direct current power, and then inverts it into alternating current and feeds it into the power grid to the maximum extent.

As of 2020, the cumulative installed capacity of China's photovoltaic market is 253GW, and the newly installed capacity is

As of 2020, the cumulative installed capacity of China's photovoltaic market was 253GW, and the new installed capacity in 2020 was 60% year-on-year. In 2020, China's photovoltaic power generation capacity was 2605

kWh, a year-on-year increase, as a proportion of total power generation.

In 2020, China's new photovoltaic installed capacity will be centralized

In 2020, China's new installed photovoltaic capacity will be, including centralized installed capacity and distributed installed capacity.

The grid-connected installed capacity of China's photovoltaic market is mainly concentrated in Q4, and the grid-connected installed capacity in Q4 in 2020 is

During the period from 2019 to 2020, the grid-connected installed capacity of China's photovoltaic market was mainly concentrated in Q4, and the grid-connected installed capacity of China's photovoltaic market in Q4 of 2020 was much larger than that of Q1-3.

From January to November 2020, the installed capacity of China's residential photovoltaic market generally showed a month-by-month growth trend, and the installed capacity was concentrated in November of 2020, and the installed capacity of China's residential photovoltaic market was 3497MW, much higher than that of other months.

In 2020, China's PV manufacturing output will be 10,000 tons of polysilicon, cell output, silicon wafer output, and module output will be 10,000 tons.

Legal analysis: solar power generation is a useful supplement to traditional power generation, in view of its importance to environmental protection and economic development, all developed countries are fully committed to promoting solar power generation, small and medium-sized solar power generation has formed an industry. There are two ways of solar power generation: photovoltaic power generation and solar thermal power generation, among which photovoltaic power generation has the outstanding advantages of simple maintenance, large or small power, and is widely used as a medium and small grid-connected power supply.

Legal basis: "Notice of the National Energy Administration on Printing and Distribution" Article 2 These measures apply to grid-connected photovoltaic power station projects and distributed photovoltaic power generation projects.

According to the current policy and business rules, distributed photovoltaic power generation.

There are three grid-connected modes of the project:

1. All self-use: all the electricity generated by photovoltaic equipment is self-use, and it is not connected to the grid;

2. Spontaneous self-use, surplus electricity on the grid: part of the electricity generated by photovoltaic equipment is used for self-use, and the remaining electricity is connected to the grid;

3. Full access to the grid: all the electricity generated by photovoltaic equipment is connected to the grid.

Hope we are helpful to you.

There are three grid-connected modes for distributed photovoltaic power generation projects:

1. All self-use: all the electricity generated by photovoltaic equipment is self-use, and it is not connected to the grid;

2. Spontaneous self-use, surplus electricity on the grid: part of the electricity generated by photovoltaic equipment is used for self-use, and the remaining electricity is connected to the grid;

3. Full access to the grid: all the electricity generated by photovoltaic equipment is connected to the grid.

The first distributed photovoltaic power generation is about 10,000-20,000 yuan per unit, which is a few thousand yuan cheaper and tens of thousands of yuan more expensive. The first distributed photovoltaic power generation is affected by many aspects such as brand, category, specification, market, etc., and it is necessary to understand and compare many aspects before choosing to buy. Distributed photovoltaic power generation refers to the photovoltaic power generation facilities built near the user's site, and its operation mode is characterized by self-consumption on the user side, excess electricity on the grid, and balanced regulation of the power distribution system.

Distributed photovoltaic power generation follows the principles of adapting measures to local conditions, clean and efficient, decentralized layout, and nearby utilization, and makes full use of local solar energy resources to replace and reduce fossil energy consumption. Distributed photovoltaic power generation refers to a distributed power generation system that uses photovoltaic modules to directly convert solar energy into electrical energy. It is a new type of power generation and energy comprehensive utilization, which has broad development prospects.

Advocate the principle of nearby power generation, nearby grid connection, nearby conversion, and nearby use. It can not only effectively increase the power generation of photovoltaic power stations of the same scale, but also effectively solve the problem of power loss in boosting and long-distance transportation. At present, the widely used distributed photovoltaic power generation system is a photovoltaic power generation project built on the roof of an urban building.

Such projects must be connected to the public grid and, together with the public grid, supply electricity to nearby users.

Spontaneous self-use surplus electricity to the Internet, full Internet access, all self-consumption. Three modes.

For distributed photovoltaic power generation applications, the State Grid allows photovoltaic power station owners to adopt three settlement modes: self-generation and self-consumption mode, self-generation and self-consumption surplus electricity on-grid or complete on-grid operation.

Generally, it is the grid of the connected power station, and the electricity is sold to the power station and then made a profit.