The explosive growth of photovoltaic power generation technology in recent years is mainly due to the fact that the price of photovoltaic system has fallen by about 99% in the past 25 years, which is undoubtedly an alarming number. But at the same time, solar photovoltaic technology, another form of solar power generation technology, can only occupy a small part of the market.
However, IEA (International Energy Agency) said that the development potential of photothermal power generation technology is very high, because the advantages of the optical thermal power generation technology can be configured with efficient heat storage system, which makes it have great advantages in reducing cost in the future, and the configuration of heat storage system can also enable the optothermal power station to continue to provide power for a long time after sunset. IEA previously released the 2014 roadmap for the development of photothermal power technology, which is expected to provide 11% of global electricity consumption by 2050. The fact that the development of thermal power generation technology is increasing in recent years also conforms to this trend, and also indicates that the development prospect of photothermal power generation will be bright.
In short, the principle of the optothermal power station is to use the reflector to gather the sunlight, and then convert the light energy into heat energy to heat the liquid medium to generate steam, so as to promote the turbine to generate electricity. For example, the tower photothermal power generation technology with rapid development is mainly used to gather sunlight to the central collector by using a Double-Dimensional tracking heliostat to collect heat and generate electricity. In addition, the more mature groove photothermal power generation technology is to focus the sunlight on the collector filled with heat conduction fluid for heat collection and power generation.
One of the key characteristics of photothermal power generation technology is that the energy produced by it is mainly expressed in the form of heat energy, and the cost of heat storage is 20 to 100 times lower than the cost of storage, and the efficiency is higher. Many commercial photothermal power stations have proved that photothermal power generation technology can store heat by using molten salt, and the heat storage time can be up to several hours.
So what is the development of the photothermal power market? In fact, the penetration of the market of photothermal power generation is indeed slower than expected, in part because the cost of photovoltaic power generation is falling at an amazing rate, but in recent years, we are pleased to see the installed capacity of photothermal power generation is increasing significantly.
An independent market analysis project in 2014 expects that the global photothermal power market will grow rapidly with a compound annual growth rate of 19.4% between 2014 and 2020. The global market for photothermal power generation in 2013 is $2.5 billion, which will surge to $8.7 billion by the end of 2020, according to the above project expectations.
In addition, both NREL and IEA said that photothermal power generation could become more valuable as PV power penetration into the power market is deeper. A 2014 NREL study showed that the photothermal power generation project with a thermal storage system "will add 5 to 6 cents per kilowatt hour for California's utility scale solar projects, which will help California achieve the 33 percent renewable energy supply target in six years."
The faster the development of renewable energy generation, especially photovoltaic power generation, the more valuable photothermal power generation is. Why do you say that? At present, photovoltaic power generation system often generates and supplies power in the most valuable period of power, such as the peak of power consumption in daytime, especially in summer, the power consumption of air conditioning becomes the main part of power demand.
But once the total PV power generation reaches 10 to 15% of the total annual generation in the region, its value is not so high. IEA believes that when this situation is common (perhaps around 2030), large-scale photothermal power generation projects will be deployed because the photothermal power station can be equipped with efficient heat storage system, and can generate and supply power at peak power demand in the afternoon and evening, and make up for the shortage of photovoltaic power generation.
In 2014, a study by the Austrian Institute of international applied systems on natural climate change found that in the Mediterranean region, a photothermal power generation project with a heat storage system that can supply continuous power can provide 70 to 80% of the current demand for electricity, and it does not cost more than gas stations. " Meanwhile, a new study led by Professor markjacobson of Stanford University shows that 7.3 percent of all clean and renewable energy (including wind, hydropower and solar energy) power supply in 50 states of the United States is provided by photothermal power plants with thermal storage system, and this part of the energy is mainly used for peak regulation and stability maintenance of power grid.
The roadmap of solar power generation released by iea2014 predicts that, under the guidance of the correct policy and policy, coupled with the continuous progress of technology, 16% of the total global electricity consumption will be provided by photovoltaic power generation by 2050, while photothermal power generation can provide 11% of the global power demand.
If everything goes according to the IEA scenario, by 2050, these solar power projects will reduce more than 6 billion tons of carbon dioxide a year, which exceeds the current national carbon dioxide emissions in the United States. In other words, the data will exceed the current direct emissions of carbon dioxide from all transport industries around the world.
