## 4 What Is Improving the Expectations in the New-Generation ICE? ICE emits particulate matter, gaseous pollutants, and CO\({}_{2}\) locally. This is accepted as it is accepted that electric cars do not. Assuming both particulars are great arguments for the replacement of ICEs, what would happen if the situation were somehow the opposite? In a life cycle analysis, neither the production of the batteries nor the production of electricity is free of CO\({}_{2}\) emissions and pollutants [15]. The generation of electricity causes CO\({}_{2}\) emissions much greater than the synthesis of liquid fossil fuels, as shown in Figure 2, as it is an energy vector more difficult to obtain and transport. It can be similarly stated that the manufacturing of ICE generates CO\({}_{2}\) emissions, although less than in the case of batteries and electric motors [46, 47], as also shown in Figure 2.  
What can ICE do to increase air quality? We can affirm that modern Euro 6d Temp Diesel engines can clean the air from particulate and smog in heavily polluted areas, such as the situations referred in China [48]. The particulate filters of modern internal combustion engines reduce the level of PM10 below the mean atmospheric value, as shown in Figure 4[49]. If one combines data in Figures 3 and 4, the advantages of ICE with particulate filters in countries such as Poland, where almost 50% of their energy mix depends exclusively on coal [12], are evident. The technology is available, and the research is driven to allow the next generation of ICEs to act as air pollutant cleaners in large cities, whose source of pollution is not only road traffic of old ICEs. This is something that electric motors with batteries cannot do. The new Diesel Euro 6d Temp is emitting 80% less NOx than stipulated by the standard. This means that they are cleaning the air of emissions coming from other sources [50]. Effective energy policies are needed to renew transport fleets around the world, as justified in [51] for the Europe case, and promote in all countries the same emission standards for ICE as in the United States, Japan, or Europe. The discussion should not focus on the type of technology but on having in the streets the most modern versions of it. Another important fact concerning ICEs is that the contribution of transport to global emissions of GWPs (Global Warming Potential) has historically remained at 11%. As shown in Figure 5 elaborated from the United Nations Food and Agriculture Organization (FAO) data [52], industry, agriculture, resource extraction, waste processing, and residential and commercial consumption do the rest. Therefore, a worldwide massive change to electric vehicles would mean a potential worldwide reduction of 11% of the equivalent tons of CO\({}_{2}\) that is emitted under the assumption of using fully CO\({}_{2}\)-free energy sources for the BEVs batteries charge. However, only 10% of world energy consumption is free of CO\({}_{2}\)[12], which means that in best of cases, the reduction would be 10% of 11%. Even the previously calculated 1.1% is not fully reachable in a life cycle analysis, as shown in Figure 2. In the very long term, it can be argued that electric cars will substantially lower their CO\({}_{2}\) emissions if electricity comes exclusively from renewable or nuclear sources. As can be seen in Figure 6, despite the large dispersion of data in the sources [13; 15; 16; 18],  
Figure 4: Diesel internal combustion engine (ICE) equipped with particulate filters as air cleaners in urban areas [49]. Figure 5: Breakdown of total greenhouse gas emissions by sector, measured in tons of carbon-dioxide equivalents [52]. this scenario is far from being fulfilled today in most of the European Union countries. Considering countries like Germany or Spain with around 35% of renewable sources in the mix, the average equivalent CO\({}_{2}\) emissions are slightly better than 2019 Diesels E6d Temp.