In 2019, the development of China's photovoltaic industry has come to a critical adjustment period. Not only the development of the whole industry tends to be orderly from “barbaric growth”, but also the entire industry chain needs to complete the all-round transformation of quality, technology and efficiency. At present, in recent years, China's photovoltaic industry has made great progress in technology, technology, efficiency and other aspects, and policy has also begun to focus on reducing the non-technical costs of the industry. It is reasonable to say that the development of the photovoltaic industry should be bright.
However, in the long run, as photovoltaic power generation is getting closer and closer to the Internet, as photovoltaic power generation is getting deeper into the national power market, there is a problem that will become a bottleneck for the urgent need for breakthroughs in photovoltaic power generation.
Photovoltaic power generation faces bottleneck
According to data released by the National Energy Administration, the national photovoltaic power generation in 2018 was 177.5 billion kWh, a year-on-year increase of 50%. In the future, as photovoltaic power generation achieves a cheaper Internet access, photovoltaic scale and power generation will be further erupted and will gradually replace traditional energy sources.
It can be said that with the advent of the era of cheap Internet access, photovoltaic power generation will face the competition of traditional coal power. In addition to the cost of electricity, photovoltaic power generation has a huge disadvantage compared to traditional coal-fired power, that is, stability. Since the intensity of sunlight is constantly changing, the voltage and current output of photovoltaic power plants are fluctuating. Even with the modulation of photovoltaic inverters, this fluctuation can only be smoothed out, and this fluctuation cannot be eliminated. The most important thing is that in the dark night without the sun, the photovoltaic power station is completely unable to generate electricity. This instability will make the power grid connected to the power station suffer.
At present, with the continuous development of photovoltaic technology, the cost of photovoltaic power generation is lower than that of traditional coal-fired power. As a result, stability may become the primary factor that weakens the competitiveness of photovoltaic power generation.
However, in terms of the mode of photovoltaic power generation, there is basically no way to solve the instability through ordinary photovoltaic systems. What can solve the stability of photovoltaic power generation is energy storage.
Energy storage is the key to breaking
In fact, the use of energy storage to solve the instability of photovoltaic power generation has long been reflected. In order to solve the fluctuations caused by a large number of access to photovoltaic power generation, the power grid generally needs to use the energy storage system to cut the peaks and fill the valleys, so as to achieve the purpose of stabilizing the large power grid system. This is the help of energy storage on photovoltaic power generation at the grid end, and this is only one of them.
In the off-grid mode, energy storage can help the photovoltaic system to stably output power and achieve a self-sufficient power mode. At present, our PV projects are all grid-connected projects, that is, they are directly integrated into the large-scale power grid system after being built, and then utilized after being deployed by the large power grid. There is no doubt that users in the grid-connected mode cannot directly use photovoltaic power. This aspect is the cause of fluctuations in power generation. On the other hand, it is also to solve the problem that power stations cannot generate electricity at night. In the off-grid mode, the photovoltaic system loads the energy storage system, and the power does not have to be integrated into the grid, but can be directly used. At the same time, the excess electricity generated by the photovoltaic system can be stored through the energy storage system so that it does not lose power at night.
At present, there are relatively few off-grid projects, mainly because the cost of energy storage systems is still high, and current policy subsidies tend to be more connected to the grid. Therefore, the off-grid mode is often not as economical as the grid-connected mode. However, in some special scenarios, such as mountainous areas and desert areas that cannot be touched by the power grid, photovoltaic systems with off-grid mode are also used. In the future, with the decline of energy storage costs and the disappearance of photovoltaic subsidies, the off-grid PV projects are expected to be widely promoted.
The above is the help of energy storage in photovoltaic power generation in grid-connected mode and off-grid mode. In addition, energy storage is also expected to help the photovoltaic industry to sprint the last mile of the Internet.
Helping the last mile of photovoltaics
As we all know, a large number of unsubsidized projects will begin to be built into the grid in 2019. Because of this, many people will call this year the unsubsidized first year. However, it is worth mentioning that not all regions of photovoltaic power generation have reached the level of parity Internet access.
From the current cost of photovoltaic power generation, only in a few areas with superior light resources, unsubsidized projects have the possibility of gaining income. As a result, the construction and development of unsubsidized projects will be concentrated in areas with superior resources. But what is worrying is that some of them represent the best-in-class I resource area, and their market development has almost stagnated.
According to the results of environmental monitoring and evaluation of photovoltaic power generation market in 2018, among the I resource areas, Jiayuguan, Wuwei, Zhangye, Jiuquan, Dunhuang and Jinchang in Gansu; the results of Xinjiang Hami, Tacheng, Altay, Karamay are red, and the other three Class I resources The area is all orange. That is to say, in the five Class I resource areas, two regions cannot arrange the scale of new PV projects, and the other three need to carefully arrange the scale of new PV projects.
This means that in the Xinjiang and Gansu I-type resource areas, which are most promising for the development of unsubsidized projects, the most unlikely to build new PV projects. Moreover, the two provinces and municipalities are still in the state of obscuring electricity and electricity for many years after they have not arranged new PV projects.
In fact, the northwestern region represented by Xinjiang and Gansu has good light resources and is sparsely populated, which is very suitable for the development of photovoltaic power generation. However, the fact that the demand for electricity in the northwest is small and the number of transmission channels is small is also a fact, which has caused the problem of power cuts.
If the energy storage system can be built on a large scale in the northwest region and the transmission channels along the way can be opened at the same time, the endless photovoltaic power in the northwest region can be easily transported to the central and eastern regions where electricity demand is high. As a result, photovoltaic power generation will re-emerge in the Northwest.
If there is no energy storage, the transmission and distribution channels and the storage of excess electricity will limit the development of photovoltaic power generation in the northwest.
Summary
In summary, as photovoltaic power generation becomes more and more close to the era of affordable Internet access, its shortcomings of stability will be exposed. Under the circumstance of energy storage, photovoltaic power generation can not only increase the application mode, expand the market scale, but also hope to break the 'discarding power limit' in the northwest region for many years, and insert 'flying wings' for photovoltaic power generation.