The relationship between international energy prices and domestic coal prices

1. Comparison of coal unit heat price at home and abroad

In the energy structure of our country, the resource endowment of "rich coal, poor oil and little gas" determines the main position of coal in our energy. As the world's largest coal consumer, more than 90% of China's coal supply is produced domestically, and imported coal accounts for less than 10% of the total supply. International coal prices and domestic coal prices under the same calorific value are compared and analyzed. As shown in Figure 6, before August 2021, domestic coal prices per unit calorific value are significantly higher than international coal prices, and the situation of domestic and foreign coal prices upside down continues to exist. After August 2021, international coal prices soared and even surpassed domestic coal prices, entering an unprecedented period of high prices, while domestic coal prices remained relatively stable under the pressure of the supply guarantee policy. Since 2022, affected by the shortage of coal supply, international and domestic coal prices have risen sharply, constantly hitting a record high, reflecting the continued tight supply of coal at home and abroad, and the lack of elasticity, the impact of accidental events on coal prices is particularly significant, and high coal prices will continue in the long run.

2. Correlation analysis between international coal and oil prices and domestic coal prices

In order to further explore the correlation between international coal and oil prices and domestic coal prices, the daily data of international oil, coal and natural gas unit heat prices and domestic coal unit heat prices in 2020-2020 were selected for regression analysis. The regression model is set as follows: Y=α+βX+μ, where Y represents the domestic unit heat price of coal and X represents the international unit heat price of coal and oil. The regression results are shown in Table 2. In Model 1 to Model 3, when the effects of changes in international energy prices are considered, when the unit heat prices of international oil, natural gas and coal change by 1 unit respectively, the unit heat prices of domestic coal will change by 0.3204 units, 0.0977 units and 0.4146 units respectively, and all pass the significance test at the 1% level. In Model 4, when considering the effects of international energy price changes, the positive and negative direction and significance of the regression coefficient do not change substantially. It shows that the rise of international coal and oil prices will push up domestic coal prices.

Even if China is the world's first coal producer, changes in international energy prices will also affect domestic coal prices. Accidental events to increase the enthusiasm of overseas coal import procurement, or will limit or significantly reduce its coal exports, coupled with the epidemic caused by the coastal coal freight continued to rise, will lead to a significant reduction in China's coal imports, exacerbate the coal supply shortage, and then push up the domestic coal prices. At the same time, when the international oil and natural gas prices continue to be at a high level, China's resource endowment of "rich coal, poor oil, less gas" is destined to tilt China's energy consumption toward cheaper and stable supply of coal, increasing coal consumption demand. The rise of international energy prices leads to the imbalance of domestic coal consumption structure from the two levels of supply and demand, which leads to the further rise of domestic coal prices along with the change of international energy prices.

Second, the impulse response analysis of oil and natural gas to coal prices

In order to further investigate the time and direction of the impact of international oil prices and natural gas prices on domestic and foreign coal prices, impulse response analysis is carried out on the basis of VAR equation. The specific reflection of coal prices affected by oil and gas price fluctuations is shown in Figure 7-10.

The impulse response of domestic and foreign coal unit heat price to oil price is stronger than that of natural gas. When the international oil unit heat price has a positive standard deviation impact, the international coal unit heat price has a strong response, and the response trend increases rapidly in a short period of time and then increases slowly. The domestic coal unit heat price responds rapidly in a short period of time, with the maximum response range of about 0.3 to the shock, and then falls rapidly, but still maintains a positive impact, and finally slowly approaches 0. This is because the price of coal per unit calorific value is lower than the price of oil, and the rise in international oil prices will tilt the energy demand toward coal, driving the increase in coal demand, and further driving the rise in coal prices. The response degree of domestic coal prices to the impact of international oil prices is relatively greater, because the domestic coal prices are affected by multiple factors, among which the national supply and price stabilization work will have a greater impact (temporary suppression), in addition, the domestic coal chemical industry is the main industrial route to replace the petrochemical industry, so the corresponding impact is more obvious.