4.1. Demand for Mineral Resources in the Clean Energy Generation Industry
Table 8 shows that offshore power generation technologies have a high demand for copper and zinc. Each megawatt of installed offshore wind power requires 8000 tonnes of copper and 5500 tonnes of zinc resources.
Table 6 shows that under the SDS, China has a higher demand for clean energy generation capacity; therefore, more mineral resources will be used for clean energy technologies.
Table 9 shows that the cumulative installed capacity of offshore wind power in China was 9 GW by 2020. In the SDS, the cumulative installed capacity of offshore wind power in 2030 is 34 times that of 2020 and 101 times by 2050. Under the STEPS, the total mineral resource demand for offshore wind power in 2020–2030 is 27 times the demand by 2020 and 63.1 times in 2020–2050. Therefore, in 2020–2050, offshore wind power technology will reach a high development stage, and its demand for mineral resources will increase to an unprecedented level.
Comparing the future mineral resource consumption between the two scenarios (
Figure 3 and
Figure 4), the mineral resources consumed by offshore wind technologies from 2020 to 2030 are 1.27 times higher than in the STEPS. Over the next 30 years (2020–2050), the SDS scenario consumes 1.61 times more mineral resources than the STEPS. The offshore wind power construction process consumes copper, zinc, manganese, and chromium, most notably copper and zinc (
Figure 4). As shown in
Figure 3, copper reaches 1.87 MT under the STEPS and 2.78 MT under the SDS scenario. In 2020–2030, the demand for copper for offshore wind technology in the SDS will be 7.2 MT. The SDS zinc consumption will be 1.63 MT over the next decade (2020–2030) and reach nearly 5 MT over the next 30 years (2020–2030). The consumption decreases in the STEPS, with 1.29 MT and 3.07 MT, respectively. From different time perspectives, the zinc consumption in offshore wind technology is 3.03 times higher in the SDS in 2020–2030 than the 2.39 times in the STEPS.
Table 8 shows that onshore and offshore wind power technologies require the same mineral resources, and the two minerals with the highest demand are copper and zinc. Offshore wind power requires the most copper, and onshore wind power requires the most zinc. However, compared to offshore wind power, onshore wind power requires less of all mineral resources. In the STEPS, 1.188 MT zinc and 0.63 MT copper and 1.63 MT zinc and 0.99 MT copper in the SDS will be consumed from 2020 to 2030—1.38 times more than in the STEPS. Onshore wind power will consume 1.61 times more minerals in the SDS than in STEPS from 2020 to 2050.
From the different time points, the new consumption of mineral resources for onshore wind power from 2020 to 2050 will be 2.64 times higher in the SDS than from 2020 to 2030, whereas this indicator is 2.59 times higher in the STEPS. Therefore, there is a significant difference in the number of mineral resources consumed in the two scenarios with the same time nodes. However, if we consider the same scenario, the ratio of the number of mineral resources consumed in the two time periods (2020–2030 and 2020–2050) is similar. The primary reason is that onshore wind power technology is mature and has a sizeable development, whereas there is a limit to the amount of wind energy resources that can be developed onshore. Therefore, compared with offshore wind power, the growth rate of the number of installed onshore wind power will gradually slow down, and the change in the demand for onshore wind power mineral resources will be smaller.
In the SDS, the cumulative mineral resource demand for onshore wind technology in 2030 and 2050 will be 2.26 and 4.3 times the cumulative demand in 2020, respectively. In the STEPS, the total installed mineral resource demand for onshore wind in 2030 and 2050 will be 1.8 and 3 times the demand in 2020, respectively. According to our assumptions, the mineral resource consumption for onshore wind power in the later stages is primarily used for replacing installed wind turbines due to lifecycle constraints. The technology development in the future sustainability scenario will be limited if more available resources are not developed or their use is not improved.
Compared with the wind energy system, the mineral resources consumed in the installed solar PV power generation system are primarily concentrated on copper and silicon and some nickel and zinc (
Table 8). However,
Table 5 and
Table 8 show that China’s PV power generation technology has a specific scale. Because the solar resources that can be developed are more abundant than wind resources, in the future construction of clean energy generation technology, the power generation and installed capacity of solar PV systems in China will far exceed those of offshore and onshore wind power.
In terms of the growth rate of mineral resource demand, under the SDS, China’s cumulative solar PV mineral resource consumption in 2020–2030 and 2020–2050 is 5 and 15 times that of 2020, respectively. Under the STEPS, the cumulative solar PV mineral consumption in 2020–2030 and 2020–2050 is 4.2 and 8.3 times that of 2020, respectively. In the STEPS scenario, the demand for copper and silicon for installed solar PV power generation reaches 2.29 and 3.21 MT from 2020 to 2030, respectively, and the demand in 2020–2050 is 2.3 times higher than in 2020–2030. The demand for copper and silicon for solar PV power generation in 2050 will reach over 5 and 7 MT, respectively. In the SDS, the demand for copper and silicon will further increase. In 2020–2030, the demand for copper is 2.8 MT and silicon is 3.91 MT, and in 2020–2050, the demand for these two minerals will reach 9.28 and 12.98 MT, respectively, 3.3 times the demand in 2020–2030.
Comparing the two scenarios, the consumption of mineral resources required for solar PV in the SDS is 1.22 times higher than that in the STEPS in the next decade (2020–2030), and this value will be 1.77 times higher in the next 30 years (2020–2050). Therefore, solar PV is a crucial clean energy generation technology for 2030–2050 and has excellent potential for development under the SDS. Under the current policy scenario, the solar PV industry’s growth rate is slow and insufficient to achieve the future energy transformation needs under peaking CO2 emissions and carbon neutrality.
Different clean energy generation technologies have different demands on mineral resources and will impact future mineral resource supplies differently. The mineral demand for offshore wind power focuses on copper, zinc, manganese, and chromium. Although the same minerals are used in offshore and onshore wind power, the two power generation technologies have different demands for the same mineral resources. Solar PV generation systems require fewer mineral resource types, and the future demand for silicon in the clean energy industry is concentrated in solar PV generation technology.
4.2. Mineral Resource Requirements for Electric Vehicles
Developing clean energy vehicles is a mandatory path for China to become a strong automotive country and is a strategic initiative to address climate change and promote green development [
31].
Table 4 shows a considerable increase in electric vehicle stock in China in 2030 and 2050 compared with that in 2020. With the pace of energy transition, electric vehicles are gradually replacing fuel vehicles. The three most used mineral resources in manufacturing electric vehicles are graphite, copper, and nickel. According to the data shown in
Table 9, China’s vehicle stock will reach 52.25 million units in 2030 under the STEPS and 72.53 million units under the SDS.
Figure 3 and
Figure 4 show that graphite, copper, and nickel mineral resource consumption for electric vehicle manufacturing will reach 3.17 MT, 2.54 MT, and 1.9 MT in 2020–2030 under the STEPS. In the SDS, the consumption of these three mineral resources from 2020 to 2030 is 1.42 times higher than that in the STEPS, at 4.60 MT, 3.62 MT, and 2.17 MT, respectively.
In our assumptions, the electric vehicle stock from 2020 to 2050 is due to a linear extrapolation of the data from 2020 to 2030. We predict that with the developing public transportation network and the decreasing birth rate, the growth rate of electric vehicle stock in 2030–2050 will not vary much from that in 2020–2030; therefore, the multiplier value of the mineral resource consumption of the electric vehicle industry in the SDS compared to the STEPS over the next three decades (2020–2050) is the same as the next decade (2020–2030). However, driven by the energy transition and the general background of reducing carbon emissions, the future of China’s electric vehicle stock will double, and its demand for mineral resources will increase. Compared with the electric vehicle stock in 2020, China’s electric vehicle stock in 2050 will be 32.8 times higher than that in 2020 in the STEPS scenario. The demand for graphite, copper, and nickel mineral resources will reach 9.5, 7.62, and 5.71 MT, respectively, and the total demand for mineral resources in the electric vehicle industry in 2020–2050 will be 32.8 times higher than that of 2020. In SDS, the cumulative mineral resource demand in 2020–2050 will be 46 times that of 2020, and the mineral resource demand for electric vehicles in 2020–2050 will be three times that in 2020–2030. Therefore, the demand for mineral resources in electric vehicle manufacturing will be one of the primary reasons for the future growth of the clean energy mineral demand in China.
4.3. Analysis of the Gap between Supply and Demand of Mineral Resources in the Clean Energy Industry
Figure 5 shows China’s mineral resource demand for clean energy technologies and the mineral resource reserves in 2020, calculated by combining the mineral resource consumption under different scenarios for each industry noted above. Without considering the mineral resource consumption for technology improvement and export, the mineral resource demand in the SDS is higher than in the STEPS. The primary reason for this is that under the SDS, China has stricter requirements for carbon emissions from energy projects and must accelerate the construction of clean energy projects to achieve the desired goals. According to
Figure 5, we predict a shortage of and a gap in mineral resources in the future clean energy development process by comparing the mineral resource demand of clean energy projects in 2020–2030 and 2020–2050 with China’s current mineral resource reserves.
By comparing the gap between China’s demand for mineral resources for clean energy technologies in 2020–2030 and 2020–2050 in different scenarios and mineral resource reserves in 2020, we find that the future expectations of the demand for some mineral resources are close to or exceed current domestic reserves (
Figure 5).
Figure 3 and
Figure 4 show that the lithium demand by 2050 exceeds 50% of the current reserves in both scenarios due to its use in electric vehicles, with 77.5% in the SDS. Clean energy technology consumption by 2050 for copper in the SDS exceeds the current mineral reserves and nickel consumption exceeds current reserves in both scenarios. The demand for nickel by 2050 is 1.52 times the current reserves in the STEPS and 2.18 times in the SDS. Furthermore, although the consumption of individual minerals is low in terms of quantity, such minerals are scarce resources in China because of the geographical distribution and other reasons; therefore, the security of supplying these minerals should be emphasised. China’s demand for cobalt ore in 2020–2030 already far exceeds the current reserves in both scenarios, whereas, by 2050, the STEPS and the SDS will reach a staggering 14 times and 20 times of reserves in 2020, respectively.
In the previous section, we highlighted that China’s overseas import demand for some rare local minerals would increase with the promotion of energy transition. The overseas supply security of mineral resources will become crucial in developing clean energy in the future. By comparing the overseas imports of these four minerals over 2016–2020 (
Figure 6), we find that with the development of clean energy technology, the annual overseas imports of copper, nickel, cobalt, and lithium are not enough for domestic supply in clean energy technology in the future but show a stable upward trend. According to China’s customs data, China’s overseas import sources of mineral resources are relatively stable. The overseas dependence on copper is approximately 78%, primarily imported from Chile, Peru, and Mexico, and the import volume of these three countries accounts for approximately 68% of the total import volume. The overseas dependence on nickel is 92%, of which more than 90% of imports come from the Philippines and Indonesia in Southeast Asia.
China’s cobalt resources are scarce, and the overseas dependence on cobalt has been high. Furthermore, 97% of cobalt consumption relies on imports, and the import sources are highly concentrated, with 99% coming from the DRC. China primarily imports lithium concentrates from Australia (95%). Regardless of the impact of the global pandemic in 2020, the security of the import source countries of various minerals and the import channels are unstable. However, the mineral import volume in 2020 was not heavily affected and is at the same level as in 2019. It is expected that under the impetus of carbon peaking and the carbon neutrality target, the overseas import volume of China’s mineral resources will increase steadily in the future as the new crown pandemic stabilises and the import routes gradually resume smoothly.
All this time, China has been developing and using existing minerals while also actively exploring new mining sites. From China’s proven resource reserves in 2016–2020 (
Table 10), the overall trend of copper, nickel, cobalt, and lithium is stable and slightly increasing. From the current data, China’s overseas imports of mineral resources and the current domestic identified mineral reserves are stable. However, due to mineral resources’ non-renewable characteristics and the urgent need for energy transformation, the gradual depletion of mineral resources is still an irreversible trend.
4.4. Mineral Material Recycling Technology
In the face of growing resource supply problems and long-term dependence on overseas imports, mineral recycling has aroused the attention of governments and manufacturers worldwide as a technology that can reduce resource consumption and improve the environment. Recycling is a way to reduce the demand for primary raw materials by generating the so-called secondary materials flows [
17]. The development of clean energy technologies in China is still in its infancy, and China started to build clean energy generation facilities on a large scale only within the last decade. As a result, research and technology for mineral recycling in the power sector are quite limited. It is worth noting that China is currently the only market with significant power battery recycling infrastructure [
38]. The average lifespan for light-duty vehicles is 15 years, whereas the average lifespan used for medium- and heavy-duty vehicles is 10 years [
39,
40]. The supply of recycled materials only represents a small portion of total battery material demand in the short term, but has the potential to represent over 50% of future cobalt [
41]. As a major automobile manufacturing country, China has been committed to the development of electric vehicles. The future in power battery recycling standards will also be at a high world level. Retired power batteries usually have a residual capacity of more than 70% of the initial capacity and a set lifetime [
42]. Referring to the recycling content of the United States under two scenarios, the recycled content of power batteries in China from 2020 to 2050 is shown in
Figure 7. A lower future mineral demand for the SDS will result in a higher recycling content than in the STEPS. In 2050, the recycling content for cobalt will be increased to 55%−58% and for nickel increased to 48−51%, which means about half of the materials used in power battery production will come from secondary materials. However, due to the current industry recovery analysis, the power battery recovery industry is not optimistic [
42]. Globally, the recycling rates of lithium are close to zero due to its abundancy and low cost. Although lithium is highly recyclable, there is currently no economic driver for this. As of now, the government and manufacturers are not paying full attention to this emerging technology. Information barriers between government, manufacturers, and consumers regarding recycling technology and willingness to recycle are also affecting the implementation of recycling technology [
42]. In the longer term, it is expected that recycling will become the major source of mineral supplies, assuring supply stability and preventing price fluctuations due to geopolitical or other factors, which will affect the supply of clean energy technology facilities [
17].