The wonderful 2022 Beijing Winter Olympics has been opened for more than ten days, the successful holding of the Winter Olympics has made Beijing the only double Olympic city in history, behind the success is inseparable from the hard-working personnel of various important positions, "green environmental protection" is a highlight of the Winter Olympics, in order to reduce emissions, large-scale use of hydrogen energy vehicles as a means of transportation. In fact, hydrogen energy vehicles have been born for many years, but the development process is not smooth, in terms of popularity, far less than pure electric models, and what is the reason behind this?
Hydrogen energy models are mainly divided into two types, one is directly based on hydrogen as an energy source, with an internal combustion engine burning hydrogen workmanship to push the vehicle, the history can be traced back to 1807 Swiss Francois Isaac de Rivaz designed internal combustion engine, the internal combustion engine will compress hydrogen stored in the balloon.
In 1941, in response to energy shortages during World War II, Soviet military technician Boris Shelishch modified 200 GAZ-AA trucks, all powered by hydrogen.
Modern hydrogen energy vehicles are hydrogen fuel as a reducing agent, hydrogen as a reducing agent, air as an oxidizer, through the combustion reaction of the fuel to convert chemical energy into electrical energy, the final resulting substance is water, this way compared to direct combustion air has a higher energy conversion efficiency, even more than 80%, and direct combustion hydrogen conversion efficiency is only more than 30%. This is the hydrogen fuel cell.
The first hydrogen fuel cell passenger car that is truly mass-produced and listed is Toyota's Mirai, which was listed in 2014, with 3 minutes of hydrogen replenishment and a range of 500km, compared to the current pure electric new energy model, the energy supplement efficiency has an absolutely overwhelming advantage, and the hydrogen fuel cell will not be so sensitive to changes in temperature, and there will be no problem of aggravated winter endurance anxiety.
Hydrogen fuel cells have many advantages over pure electric vehicles, such as Toyota, Honda, Hyundai these large factories before and after the research and development of more than ten years, so far the popularity is far less than pure electric vehicles, mainly subject to cost, energy production and safety of the three major issues.
In the case of Toyota's Mirai, the catalyst used in hydrogen fuel cells is platinum, the production is extremely low, and the price is extremely high, while the proton exchange membrane used in the fuel cell is monopolized by DuPont and another Japanese company, which ultimately pushes up the price of the vehicle itself.
The second is the production of energy, hydrogen is a secondary energy, the simplest and most direct way to prepare hydrogen is to electrolyze water, which is also learned in the textbooks of our student era, and can also produce oxygen, but the energy consumption of electrolyzed water to prepare hydrogen is very high, and this method is mostly the way used by the laboratory.
Proportion of continental hydrogen preparation
At present, the world's main preparation is through natural gas, accounting for 42%; industrial by-products account for 39%, coal to hydrogen accounted for 18%, and other ways to produce hydrogen accounted for 1%. The proportion of hydrogen production in the mainland, industrial by-products and natural gas hydrogen production was 64%, 21% and 14% respectively, and hydrogen production by other methods was 1%.
The mainland is a coal-rich country, natural gas and oil foreign dependence is relatively high, and coal to hydrogen will produce a large amount of carbon dioxide, every 1 kg of hydrogen produced, carbon dioxide emissions of about 30.2kg, coal itself also contains a large number of impurities, the development of new energy itself is to reduce carbon emissions, which obviously violates the theme, as for the preparation of natural gas to be more environmentally friendly, but the gap in natural gas itself is not small, small to cooking, large to industrial production, taxis, commercial vehicles will be used, exclusive hydrogen preparation is obviously unrealistic.
Finally, the safety of use, hydrogen is currently known to be the smallest density of gas, very flammable, its explosion density between 4% -75.6%, the explosion range is very broad, if you have been in the open environment and do not need to worry too much, but the car is to stop in the basement, once the leakage occurs in the basement, the explosion density is reached, and there are a large number of switches and electrical equipment in the basement, once the explosion is very dangerous, if there are many identical cars in this basement, the result is unimaginable.
With the current technical conditions, it is impossible to achieve 100% non-leakage, hydrogen fuel cell vehicles are obviously not realistic for large-scale popularization to passenger cars, and it is relatively safer for fixed-line commercial vehicles to use the environment.
Hydrogen energy giant Toyota has gone through decades on this road, although it has achieved mass production, but so far hydrogen energy models can not achieve large-scale rollout, not long ago Honda, Daimler, etc. have announced the cessation of research and development of hydrogen fuel cells, compared to pure electric models, hydrogen energy in the automotive field can be said to be bitter support. At the national level, hydrogen energy is very important, the United States, Japan, the European Union have upgraded hydrogen energy to the level of national strategy, hydrogen energy in the mainland is also one of the six major future industries in the 14th Five-Year Plan, hydrogen energy may be the ultimate energy of the future, but not now, pure electric vehicle models even if there are many shortcomings, comprehensive but the most suitable.