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Whether electric cars can protect the environment

There have been many controversies about whether electric cars are environmentally friendly. Click here to learn more about electric cars. One of the biggest controversies is that although electric cars can achieve zero emissions, coal-fired thermal power plants account for a very high proportion of China's electricity energy mix, so electric cars only transfer pollution to the power plants.

Based on this analysis, there were many people who expressed the view that "electric cars are not environmentally friendly." In particular, the head of Toyota, Akio Toyoda, recently used the same logic to "demonize" electric cars as not environmentally friendly. In a press conference held by the Japan Automobile Manufacturers Association at the end of the year, Akio Toyoda said that promoting electric cars in a country like Japan, where most of the electricity comes from coal and natural gas (70% of Japan's total electricity generation comes from fossil fuels), is not good for the environment. With this statement, many people once again began to attack electric cars as not being environmentally friendly.

At first glance, this logic seems to make sense. In 2019, for example, the nation's interregional power plants generated 7.14 trillion kWh of electricity, up 3.5% from the previous year, while thermal power plants generated 5.16 trillion kWh, up 1.9% or 72%. Coal is not a clean energy source. Its combustion produces dust, nitrogen oxides, sulfur dioxide, carbon monoxide, carbon dioxide, and other pollutants that are more serious than the pollution caused by oil. Electric vehicles are currently powered mostly by thermal energy, and using electricity as a substitute for fuel seems only to shift pollutant emissions.

Is this view correct? A few years ago, Tsinghua University researchers Ou Xunmin, Zhang Xiliang, Qin Yining, and Qi Tianyu used the Well-to-Wheels (WTW) module of Tsinghua University's CA3EM model in an article titled "A full life-cycle analysis of future coal-powered electric vehicles." In this paper, the life-cycle energy consumption and greenhouse gas emissions of five coal-powered electric vehicle routes are quantified using the Well-to-Wheels (WTW) module of the Tsinghua-CA3EM model, with 2020 as the target year, and compared with integrated grid-powered routes and conventional gasoline vehicle routes.

Based on the analysis of the electricity use chain, the energy consumption and emissions of the resource extraction, transportation, and electricity transmission and distribution phases were fully considered. The results show that: the life cycle energy consumption of electric vehicles is 1123-1. 592 kJ/km and the greenhouse gas equivalent CO2 is 131-162 g/km; compared with the gasoline vehicle route, the advantages of the electric vehicle route in terms of energy saving and emission reduction are obvious, with energy saving of more than 35% and emission reduction of about 20%; while the use of integrated coal gasification The advanced power supply technology of combined power generation and carbon capture and storage can reduce greenhouse gas emissions by up to 80% and energy consumption by up to 40% compared with the gasoline route.

On March 28 of this year, Nature Sustainability, a sub-publication of Nature, published a major research study that also refutes the claim that "electric cars are not environmentally friendly." A new study by researchers at Radboud University in the Netherlands and Cambridge University in the United Kingdom concludes that fears that electric vehicles will increase carbon emissions are almost always unfounded. Dr. Florian Knobloch, corresponding author of the study and from the Department of Environmental Sciences at Radboud University in the Netherlands, says, "We counted data from cars and heating systems around the world, and even in the worst case, carbon emissions (from electric cars) are reduced."

It is true that coal is not a clean source of energy in the traditional sense, but the country has made great strides in generating electricity from coal thanks to the promotion and application of advanced technologies. At the end of 2016, all existing coal-fired power plants in China completed dedusting, desulfurization and denitrification, and the emission concentrations of the three pollutants soot, sulfur dioxide and nitrogen oxides are no higher than 10 mg / m3, 35 mg / m3 and 50 mg / m3 with a base oxygen content of 6%. Xie Kechang, an academic from the Chinese Academy of Engineering, said in 2019 that "ultra-low-emission technology can minimize particulate matter emissions from coal-fired power generation through end-of-pipe treatment," and China's operational data has shown that the fine dust emissions are greatly reduced after reaching the ultra-low emissions and that some pollutants are lower than the natural gas emissions. China's coal-fired power generation is now the world leader in terms of pollutant emissions.

Although thermal power has always been absolutely dominant in China's electricity-energy mix, China has made very rapid progress in the generation of renewable energies in recent years. Electricity generation from renewable energies reached a value of 2.04 trillion kilowatt hours in 2019, which corresponds to an increase of around 176.1 billion kilowatt hours compared to the previous year; the share of renewable energies in total electricity generation was 27.9% and thus 1.2 percentage points higher than in the previous year. Including hydropower 1.3 trillion kWh, an increase of 5.7% compared to the previous year; Wind energy 405.7 billion kWh, an increase of 10.9% compared to the previous year; Photovoltaics 224.3 billion kWh, an increase of 26.3% compared to the previous year; Electricity generation from biomass 111.1 billion kWh, an increase of 20.4% compared to the previous year. While the growth rate of thermal energy in the same period was only 1.9%. As China's installed capacity of renewable energy generation continues to grow, the future of electric vehicles in "clean energy" will naturally be more and more.

In addition, China's energy structure has long been characterized by "a lot of coal, little oil, little gas". China's coal resources total 5.9 trillion tons, which is 94% of total primary energy resources, while oil and gas resources are only 6%, and it is difficult to increase production and the degree of foreign dependency is high (im In 2019, the degree of foreign dependency for crude oil is up to 70%). China's coal reserves are much larger than the country's proven oil reserves, and coal production is also much larger than oil production, and the gap between China's coal and oil production has gradually widened in recent years. That is why "coal instead of oil" has become an important energy strategy for China. Electric vehicles that use electricity as an energy source are clearly one way to implement this strategy.

Some people may fear that the use of electricity in cars will lead to a scarcity of electricity in society as a whole. In fact, the explosive growth of all-electric vehicles will not have much of an impact on electricity supply. According to the current vehicle ownership in China, about 200 million calculations, even if an electric car average 50 km per day, power consumption of 16 degrees (this is already the mainstream electric car 100 km power consumption), 200 million is only 3.2 billion kilowatt hours. And since the country's daily electricity generation is now around 25 billion kWh, 3.2 billion kWh is less than a fraction of the total electricity generated. It will take about 20 years for electric vehicles to become fully popular in China, and by then the country's power generation will surely increase even more. It can be said that there is enough power for electric vehicles even with the power supply.

In summary, it can be said that we should look at the question of whether or not electric cars are environmentally friendly from a development-policy and systematic perspective. Currently, the technology of coal-fired power generation is improving, the technology of electric vehicles is improving, the power consumption of electric vehicles per kilometer is falling, and the proportion of clean energy is increasing. ...... From many perspectives, electric vehicles will only become more environmentally friendly in the future.