The energy produced by the sun is almost unlimited for human beings. Solar photovoltaic power generation refers to the utilization of solar energy that directly converts the light energy of the sun into electrical energy without thermal processes. Relying on photovoltaic cells, photovoltaic power generation that directly converts the light energy irradiated on photovoltaic cells into electrical energy output is the mainstream of solar photovoltaic power generation.
What are the advantages of solar photovoltaic power generation?
The main advantages can be listed as follows:
(1) The structure of solar photovoltaic is simple, small and light;
(2) Solar photovoltaic power generation has the advantages of easy installation, easy transportation, short construction period, etc., and it takes a short time to obtain energy;
(3) It is easy to use and easy to maintain, and it can work normally in the temperature range of -50℃~-65℃;
(4) Safe and reliable, no noise, no pollution discharge, absolutely clean (no pollution);
(5) Because it is solar photovoltaic power generation, it can not be restricted by the geographical distribution of resources, and can take advantage of the advantages of building roofs; for example, areas without electricity, and areas with complex terrain;
(6) The speed of price reduction is fast, and the energy repayment time may be shortened;
(7) It can be matched with the battery to form an independent power supply, or it can be connected to the grid to generate electricity.
Power transmission lines can generate electricity locally
The main disadvantages of solar photovoltaic power generation are:
(1) The solar energy density is low and the coverage area is large;
(2) Photovoltaic power generation is intermittent and random; (3) Compared with thermal power generation, the cost of power generation is currently high. (4) The manufacturing process of photovoltaic panels is not very environmentally friendly.
(5) The situation of solar energy resources in various regions is different, so photovoltaic power generation is strong regionally.
Current limitations of solar power:
The most criticized is the instability of the output power, because the light on the earth is the sunlight absorbed by the atmosphere, and the revolution and rotation of the earth lead to the change of the light at the exact location on the ground, so that the output power also changes accordingly. There are many ways to stabilize the output, but because the current production cost of solar cells is still high, these ways are not economical, so at present, it is necessary to use energy storage measures (grid, battery, etc.) to output unstable photovoltaic output. Power becomes stable and available. We believe that solar cells will eventually be a very cheap semiconductor device, and the stability problem can be solved without energy storage.
As for the issue of intermittency, we all have a “fantasy”, a global solar grid, that is, with enough solar cells installed around the earth, this super solar photovoltaic power station can generate enough electricity for the world’s human needs at any time. will make it happen!
The second limitation is caused by the relatively low conversion efficiency, which requires a large installation area and cannot be miniaturized or miniaturized as in nuclear energy. With the development of technology, this problem will be improved to a certain extent, but even if the conversion efficiency of 100% is 1000W or more per square meter, there is an upper limit. Of course concentrators are more efficient.
Last but not least, the solar power generation industry is mature enough to make greater contributions to social development. From the perspective of investment and financial management or environmental protection and energy conservation, you can invest in the installation of solar photovoltaic power generation systems!
Pollution from solar power generation:
When it comes to the photovoltaic industry, some people think that it is a “high pollution, high energy consumption” industry. A lot of pollutants will be generated in the production process of photovoltaic crystalline silicon modules, which goes against the original intention of green development, and many self-media make a big fuss.
But we have to recognize a fact: having pollutants and causing pollution are two completely different concepts. Pollutants will only cause pollution if they are not disposed of; on the contrary, if they are disposed of legally, they cannot be called environmental pollution. From the national level, as long as the discharge can meet the standard, it is considered as “no pollution”.
At present, the purification of crystalline silicon uses a modified Siemens production process, and the production process does produce by-product silicon tetrachloride (highly polluting and highly toxic waste liquid), as well as hydrogen and chlorine. If silicon tetrachloride is directly discharged, it will decompose and generate hydrogen chloride when exposed to humid air, which will cause environmental pollution. However, China’s crystalline silicon production enterprises have already realized closed-loop production of the improved Siemens method, achieving “controllable and returnable”, from synthesis to distillation, from reduction to tail gas separation, to achieve recycling. Therefore, there is no factual basis for the high pollution caused by photovoltaics.