Working principle of photovoltaic power generation system;

High-performance solar cell modules are centrally installed on the roof through brackets, and a solar cell array is formed through series-parallel connection. The solar cell array absorbs sunlight to generate direct current, which is converted into household alternating current by photovoltaic inverter and uploaded to the power grid.

Income measurement

Take the third-class area in Hunan as an example, install a 5KW family power station, and invest about 25,000 yuan at the market price (calculated by the quotation of first-class brands). On average, it can deliver 16kw/h in one day and 5500kw/h in one year. According to the calculation, 50% is for personal use and 50% is sold to the State Grid:

Subsidy income: 5500*0.32= 1760 yuan (after May 3 1, 2065438, according to the state subsidy of 0.32, excluding provincial and municipal subsidies).

Power saving benefit: 5500*50%*0.588 (electricity) = 16 17 yuan.

Revenue from electricity sales: 5500*50%*0.45 (according to local desulfurization coal price) = 1237.5 yuan.

The combined annual income is1760+1617+1237.5 = 4614.5 yuan.

According to the initial investment of 25,000 yuan, the cost can be recovered in almost 6 years, and the average running time of photovoltaic power plants is 25 years, which means that the next 19 years are net income.