Solar Photovoltaic

- Jun 25, 2019-

An overview :

The solar photovoltaic system, also known as light volt, hereinafter referred to as photovoltaic (Photovoltaics, Word source "photo-" light, "voltaics") refers to the photovoltaic semiconductor materials using the photovoltaic effect of solar energy into direct current power facilities. The core of photovoltaic facilities is solar panels. At present, the semiconductor materials used for power generation mainly include monocrystalline silicon, polycrystalline silicon, amorphous silicon and cadmium telluride. In recent years, countries are actively promoting the application of renewable energy, the development of photovoltaic industry is very rapid. 

As of 2010, solar photovoltaic is in use in hundreds of countries around the world. Although its capacity still accounts for only a small fraction of humanity's electricity, the amount of photovoltaic power connected to the grid has grown by an average of 60% a year since 2004. By 2009, the total power generation capacity has reached 21GW, which is the fastest growing energy source. It is estimated that the current capacity of photovoltaic systems, which are not connected to the grid, is about 3 to 4GW.

The photovoltaic system can be installed on the ground as a photovoltaic power station on a large scale, or placed on the roof or outer wall of a building to form the integration of photovoltaic buildings.

Since the advent of solar cells, advances in materials, technology and the maturity of manufacturing have driven photovoltaic systems to become cheaper. Moreover, many countries invest a lot of research and development funds to promote the conversion efficiency of photovoltaic, and give financial subsidies to manufacturers. What's more, feed-in tariff policy and renewable energy ratio standard have greatly promoted the wide application of photovoltaic in various countries.

application

In 1954, bell LABS produced photovoltaic cells with a 6% efficiency; Since 1958, the photovoltaic effect has been applied in the field of space satellite power supply for the first time in the form of photovoltaic cells. Today, from automatic parking meters to rooftop solar panels to vast solar power centers, its applications in the field of power generation have spread all over the world.

limited

The production process

Solar panels are made from the same materials as computer chips. The mass production process requires a lot of energy, toxic and harmful chemicals. Chemical substances are mainly controlled by local laws and regulations. Some solar plants have installed solar systems that use the clean energy generated by solar systems to produce solar panels.

The impact on the grid

As of December 2017, more than 31 percent of residents in the eastern state of Queensland had rooftop solar systems with an average installed power of more than 3.5 kilowatts (the highest in the world). But high solar penetration also poses problems for grid voltage. Residential areas at noon low electricity consumption, mainly to sell electricity to power companies. The traditional grid does not consider two-way transmission. When a large amount of electricity is transmitted back to the grid in residential areas, the voltage will gradually rise, and may exceed the range of electrical equipment. Scientific research has found ways to solve this problem, but there are various cost considerations, such as adding additional voltage control devices to the medium-voltage grid.

Implications for other countries and regions: without systematic analysis and planning, a single incentive to promote solar power in residential areas will bring new risks. One of the better ways would be to promote solar installations for industrial and commercial users, through taxes or other incentives. Because the peak electricity consumption of industrial and commercial users is usually in the daytime, the solar energy system generates electricity during the daytime in the sunshine to supplement the electricity consumption of industrial and commercial users and reduce the pressure of industrial and commercial users on the power grid.

Impact on energy investment and electricity management

The problems in real life are often complicated and changeable, and the reasons are complicated. The same is true for energy investment and electricity management. There is no one-size-fits-all solution. Investment in solar systems may be a good option if: local sunlight is abundant, electricity prices are high and prices continue to rise, the government supports them financially or financially, and electricity can be sold back to power companies (Australia and Germany). Return on investment is often the main consideration for energy investments. But a systematic review, assessment and analysis may find that a comprehensive approach is most appropriate in the current market conditions. For example, improvements in the energy efficiency of buildings, the operation of existing equipment, and investments in solar systems may provide homeowners with the best return on investment.