Nine Green Days: this 720,000 km2 province achieves all-clean energy power supply
Time:2019-02-13 10:34:00
From 0:00 on June 20 to 24:00 on June 28, 2018, Qinghai Province achieved all-clean energy power supply for 216 hours during nine days, also known as “Nine Green Days”. During this period, the electricity used in the whole Qinghai Province was the clean energy generated from solar power, hydropower and wind power, and the electricity consumption in the province realized zero emission.
“Nine Green Days” is the longest all-clean energy power supply activity in the world
The use of clean energy is not uncommon, but the full use of clean energy in a region for nine days in a row is undoubtedly a pioneering initiative. The exploration of “Nine Green Days” is already the second consecutive year in Qinghai Province to carry out all-clean energy power supply, once again breaking the world record held by itself. Before that, only Portugal had carried out similar explorations in the world.

Statistics from the control center of State Grid Qinghai Electric Power Company show that during the nine green days, the maximum load of Qinghai’s power grid was 8.538 million kilowatts, the province’s electricity consumption was 1.76 billion kWh, the clean energy generated was 2.031 billion kWh, including 1.612 billion kWh of hydropower, 323 million kWh of PV power, and 96 million kWh of wind power.
Excellent power energy structure is the basis of realizing “Nine Green Days”
Located in the northeast of Qinghai-Tibet Plateau, Qinghai is one of the 13 major hydropower bases in China, with abundant sunshine, rich light and heat resources, and large Gobi desert, which are unique conditions for the development of new energy including wind power, photovoltaic power.
Qinghai’s clean energy is widely distributed and highly complementary in time and space. There are complementary characteristics between light and light, wind and wind, wind and light, wind, light and water, which can smooth the fluctuation of new energy output. Meanwhile, the quality of new energy generation can be significantly improved by using the rapid regulation capacity of hydropower and the energy storage of light and heat.

The overall power energy structure of Qinghai shows that clean energy power generation has occupied a high proportion. By the end of May 2018, the total installed capacity of Qinghai Power Grid was 26.4 million kilowatts, including 11.91 million kilowatts of hydropower and 10.7 million kilowatts of new energy, accounting for 45.1% and 40.5% of the total installed capacity of the province respectively. As the second largest power supply source in the province, new energy has been close to hydropower in the installed capacity.
According to Qinghai Power Grid, by 2020, the total installed capacity of new energy in Qinghai will exceed 20 million kilowatts, which is expected to exceed 50% of the total installed capacity of the province.

Power energy structure of Qinghai Province
“Nine Green Days” provides a fresh perspective to solve the peak-shaving problem of high-proportion new energy power generation
During the “Nine Green Days”, Qinghai introduced “two mechanisms” and “two technologies” to solve the peak-shaving problem of high-proportion new energy power generation.
The “two mechanisms” are thermal power peak-shaving compensation mechanism and load participation peak-shaving mechanism. The former solves the compensation problem of stop & stand-by and deep peak-shaving thermal power units, and the latter solves the problem of photoelectric absorption maximization. The “two technologies” include multi-energy complementary coordinated control technology and big data application technology. Simply put, it is to coordinate different energy sources to achieve “best match,” and rely on big data platform and multi-energy complementary measures to improve the management and control of new energy and ensure the safe and reliable operation of the power grid. In addition, Qinghai also explored the use of market-oriented means to mobilize power stations, users and power grid to work together.

During the “Nine Green Days”, Qinghai successively organized and coordinated the peak-shaving thermal power plants at stop & standby periods to carry out power generation rights transactions with new energy companies, and the direct transactions between new energy companies and the clean heating projects in the Sanjiangyuan region, so as to maximize the adsorption of new energy. The control centers at the national, northwestern and Qinghai provincial levels worked together to give full play to the resource allocation ability of the big power grid, promote the regional energy coordination and consumption through peak-shaving, and ensure reliable supply of power and safe operation of the power grid.

“Nine Green Days” is an exemplar for wide application of renewable energy
Internationally, only the Portuguese power grid achieved 107 hours of electricity supply entirely dependent on renewable energy in 2016, but China’s attempt this time is longer, the proportion of photovoltaic power generation is higher, and the power supply is more difficult.
From “Seven Green Days” to “Nine Green Days”, Qinghai Province, which is located in the “origin of three rivers”, advocates the ideal of green development with vivid practice, showing people the broad prospects of minimizing dependence on fossil energy and promoting the use of clean energy.
During the “Nine Green Days”, the cumulative clean energy power supply was 1.76 billion kWh, equivalent to reducing coal combustion by 800,000 tons and reducing carbon dioxide by 1.44 million tons. In the process of global energy transition, Qinghai’s practice left an important footprint, which is of symbolic significance to the energy transition in China and even the whole world.
It’s learnt that Qinghai plans to build 100% renewable energy provincial power system by 2030 to achieve 365 days of clean energy power supply.
The experience and enlightenment of “Nine Green Days”
According to the experts from the National Renewable Energy Center, in the process of using clean energy power supply in Qinghai for nine days in a row, the dispatching plans of different provinces in the northwest region were fully coordinated, the inter-provincial interest barriers were broken down, and the absorption of renewable energy was promoted in a wider range, which has created a typical case with beneficial experience and enlightenment for the wide use of new energy.
Construction of UHV grid and optimization of resource allocation
“Big power grid, big market” are undoubtedly the key words of this case. For Qinghai, an economically underdeveloped area where energy resources and demand are inversely distributed, if there is no unified big power grid with UHV as the backbone and coordinated development of power grids at all levels to carry out optimal allocation of resources throughout the country, it will be difficult to make such an attempt.
By 2020, Qinghai’s planned new energy generation capacity will exceed 20 million kilowatts, and UHV channels will be built simultaneously, which has been incorporated into the national energy development plan. During the 13th Five-Year Plan period, Qinghai will enhance the ability to absorb clean energy in the province through direct electricity trading and other means. At the same time, it will build the country’s first UHV transmission channel dedicated to the transmission of clean electricity, which will be located in the central region.
Relying on big power grid and trying multiple market transaction varieties to meet the demand for green power
“Nine Green Days” is a test of the effectiveness and flexibility of the inter-provincial trading mechanism of the power trading platform. After summing up and improving, the relevant market trading mechanism can be further applied in other regions to promote the consumption of new energy.
Some experts believe that in order to improve the new energy consumption throughout the country, we should further break down market barriers, optimize the allocation of resources on a larger scale; further improve the relevant trading mechanisms, establish more systematic rules for new energy to participate in market transactions, improve the connection between market transactions and guaranteed acquisitions, effectively balance the interests of new energy enterprises and conventional power generation enterprises; further innovate the variety of transactions, increase the frequency of transactions, and better adapt to the characteristics of new energy participating in market transactions.
Making a rational layout of various power sources in the plan to form a multi-energy complementary clean energy utilization model
The realization of “Nine Green Days” is attributable to Qinghai’s rich new energy resources and excellent electric power structure. With the continuous progress of photovoltaic and other new energy technologies and energy storage technologies, its application proportion and role will be further increased. At present, many areas, including Qinghai, are carrying out planning research on the complementary and coordinated development and transmission of photovoltaic, wind, photothermal energy storage, and pumped storage. Raising awareness from the planning level, and forming a multi-energy complementary clean energy utilization model is undoubtedly the key to promote the transformation of energy structure.
The high-proportion clean energy utilization in China and even in the world cannot be solved by a demonstration and efforts by one province, but needs to be planned as a whole at the overall level, improve relevant policy support, turn location advantage into economic advantage, and avoid the waste of resources. Increasing the proportion of photovoltaic power generation and wind power through more attempts to actively absorb clean energy is of great significance to the large-scale development of renewable energy and the construction of a more reasonable national energy system.

Reproduced from: weienergy, TESTPV.COM