Top 10 factors affecting solar energy power generation

Top 10 factors affecting solar energy power generation

Top 10 factors affecting solar energy power generation

Ten factors of solar energy power station power generation

Amount of solar energy radiation, intensity

On Earth, our energy basically comes from the sun, and electricity is no exception. Our electrical energy is also obtained from solar energy conversion in different ways.

The radiant energy of the sun provides the primary source of power for various renewable energy technologies, such as solar panels, which convert sunlight into electricity, thereby reducing our reliance on fossil fuels and mitigating climate change.

The sun is a scorching fireball. The temperature of its surface is about 6000°C, while the temperature in the center reaches 20 million°C. It continuously radiates light and heat outward.

The scorching fireball of the sun is very far away from us. It radiates light and heat at a speed of 300,000 kilometers per second, and it takes 8 minutes to travel to the earth.

  • Among the many energy sources available to human beings, the one with the highest grade should undoubtedly be electrical energy. It can be converted into other energy forms very conveniently: magnetic energy, light energy, thermal energy, chemical energy, etc. And it is easy to transmit, which is something other energy sources cannot do.
  • In a broad sense, the energy on the earth is almost all solar energy. In a narrow sense, solar energy is divided into photothermal and photoelectric
  • When the conversion efficiency of solar energy cell modules is constant, the power generation of the photovoltaic system is determined by the radiation intensity of the sun.

China’s solar resources have spurred significant investments in renewable energy infrastructure, positioning the nation as a global leader in solar energy technology development and deployment.

  • Sunshine time: Meteorologically, the time when solar radiation exceeds 120W/120W/square meter per day is of little significance.
  • Peak solar (sunshine) hours. This is an equivalent concept, which refers to the number of hours per day when the solar radiation intensity exceeds 1KW square meters (standard light intensity measured by solar cells). It is numerically equal to the average daily radiation divided by the standard light intensity. The unit is h/d (hour /sky)

Summarize

  • The frequency response of different solar cells is different, usually between 300-1200nm.
  • Near-infrared and near-ultraviolet rays can generate electricity.
  • Solar constant Solar constant: The intensity of solar radiation per unit area of vertical sunlight at the average distance between the sun and the earth outside the earth’s atmosphere, expressed as AM0.

1367W±7W/m2, 25℃, 1000W/m2, AM1.5 are the test conditions for solar cells.

Solar energy is a renewable
Solar energy is a renewable

Tilt angle of solar energy cell module

The data obtained from weather stations generally only include the total amount of solar radiation H on the horizontal plane, the amount of direct radiation Hb and the amount of scattered radiation Hd. And: H=Hb+Hd can be obtained for the total amount of solar radiation on the inclined surface and the direct-dispersion separation principle of solar radiation. For the total amount of solar radiation on the inclined surface and the direct-dispersion separation principle of solar radiation, it can be obtained. The total amount of solar radiation Ht on the inclined surface is composed of the direct solar radiation amount Hbt, the sky scattering amount Hdt, and the ground reflected radiation amount Hrt. Ht=Hbt+Hdt+Hrt

in conclusion

  • What the meteorological department provides is the amount of direct radiation and scattered radiation from the sun on the horizontal plane, which is different from our actual application.
  • The direct tilt angle design of grid-connected solar cells only needs to consider the maximum total power generation throughout the year, which is much simpler than an independent power generation system.
  • The specific method can use table lookup or software methods.

Solar cell efficiency

  • In 2000, the world’s annual solar cell output exceeded 287.7Mw, and the installation exceeded 1,000Mw, marking the arrival of the solar energy era;
  • In 2001, the world’s annual solar cell output exceeded 399Mw; Wu x., Dhere R. G., A|bin D.s. and others reported that the efficiency of cadmium telluride (cdTe) cells reached 16.4%; the price of monocrystalline silicon solar cells is about 3USD/W;
  • In 2002, the annual output of solar cells in the world exceeded 540Mw; the price of polycrystalline silicon solar cells was about 2.2USD/W; in 2003, the annual output of solar cells exceeded 760MW; the efficiency of Germany’s FratInhofer ISE’s LFC (Laser-fired contact) crystalline silicon solar cells reached 20 %;
  • In 2004, the annual output of solar cells exceeded 1200Mw; Germany’s Fraurlhofer ISE polycrystalline silicon solar cell efficiency reached 20.3%; amorphous silicon cells accounted for 4.4% of the market, down to 1/3 of 1999, CdTe accounted for 1_1%; and CIS accounted for O. 4%;
  • Through technological breakthroughs in 2010, solar cell costs were further reduced and accounted for a certain share of the world’s energy supply; Germany’s renewable energy power generation reached 12.5%;
  • In 2020, the cost of solar cell power generation will be close to that of fossil energy, with renewable energy accounting for 20% in Germany;
  • Solar cell power generation will reach 10% to 20% in 2030; Germany will close all nuclear power plants;
  • In 2050, the world’s solar energy utilization will account for 30% to 50% of the world’s total energy consumption.

Summarize

Since the beginning of this century, my country’s solar energy photovoltaics have entered a period of rapid development. The efficiency of solar cells is constantly improving. With the help of nanotechnology, the conversion rate of silicon materials can reach 35% in the future, which will become a breakthrough in solar energy power generation technology. “Revolutionary breakthrough”.

widespread adoption of solar energy
widespread adoption of solar energy

Combination loss

  • Any series connection will cause current loss due to the current difference between components;
  • Any parallel connection will cause voltage loss due to the voltage difference of the components;
  • The combined loss can reach more than 8%, and the standard of China Engineering Construction Standardization Association stipulates that it is less than 10%.

Summarize

  • In order to reduce the combination loss, components with consistent current should be strictly selected and connected in series before installation in the power station.
  • The attenuation characteristics of components are as consistent as possible. According to the national standard GB/T–9535, the maximum output power of solar cell modules is tested after testing under specified conditions, and its attenuation shall not exceed 8%.
  • Isolating diodes are sometimes necessary.

Temperature characteristics

Summarize

When the temperature rises by 1°C, the maximum output power of crystalline silicon solar cells decreases by 0.04%°C, the open circuit voltage drops by 0.04% (-2mv/°C), and the short-circuit current increases by 0.04%.

In order to avoid the impact of temperature on power generation, the components should be kept well ventilated.

Dust loss

The dust loss of the power station may reach 6%! Therefore, components need to be wiped down frequently.

Maximum Power Point Tracking (MPPT)

Summarize

From the perspective of solar cell application, the so-called application is tracking the maximum output power point of the solar cell. The MPPT function of the grid-connected system is completed in the inverter. Recently, some people have studied putting it inside the DC combiner box.

When considering the advantages and disadvantages of solar energy, it’s important to weigh its renewable and environmentally friendly nature against factors such as intermittency and initial setup costs.

Line loss

The line loss of the system’s DC and AC circuits must be controlled within 5%. For this reason, wires with good electrical conductivity must be used in the design. The wires need to have sufficient diameter, and cutting corners is not allowed in construction.

During system maintenance, special attention should be paid to whether the connectors and terminals are secure.

Controller, inverter efficiency

The voltage drop of the controller’s charging and discharging circuits shall not exceed 5% of the system voltage. The efficiency of grid-connected inverters is currently greater than 95%, but this is conditional.

Battery efficiency

Independent photovoltaic systems require batteries. The charging and discharging efficiency of the batteries directly affects the efficiency of the system, that is, the power generation of the independent system. However, this has not yet attracted everyone’s attention.

The efficiency of lead-acid batteries is 80%; the efficiency of lithium phosphate batteries is more than 90%

widespread implementation of solar energy systems
widespread implementation of solar energy systems