Who’s in the Race?
Author: Michael Specht
Comfortable, quick, flexible – and before all else sustainable – is how we envisage our future mobility. Which drive systems have what it takes to fulfil these demands? We provide an overview of alternative powertrain concepts.
Mobility is among the basic needs of modern man, and the global motor vehicle fleet is growing continuously. According to the Organisation Internationale des Constructeurs d‘Automobiles (OICA), there were 892 million motor vehicles in 2005. Ten years later, in 2015, the number had already hit 1.28 billion. Against the background of climate debates surrounding emissions and fossil fuel consumption, the question of what the future of mobility might look like is growing. What sustainable alternatives are there to the millions of gasoline and diesel engines on the world’s roads today?
Population growth, coupled with increased traffic loads continues to increase energy consumption. According to the United Nations (UN), the Earth’s population will hit 9.8 billion people by 2050. “By then, the stock of vehicles would be close to two billion, with the number of initial registrations exceeding 120 million annually,” estimates Peter Fintl, Manager of consulting and engineering group Altran. According to statistics prepared by the German Association of the Automotive Industry (VDA), the global figure for first registrations lay around 84 million in 2018.
- 59.4 grams per kilometer – from 2030, this will be the maximum fleet CO2 emission value for new cars sold by manufacturers in the EU
Even though we have been comfortably refueling with conventional fuels for many decades, which grant virtually unlimited mobility, a rethink is taking place. Vehicle manufacturers are under both political and societal pressure to develop clean alternative powertrains for their products. By the end of 2020, the EU Commission will impose an average fleet output of no more than 95 grams of CO2 per kilometer on manufacturers, and there is scope for far more change. Vehicle manufacturers that fail to meet targets will face hundreds of millions of Euros in fines – not to mention considerable brand damage. “Environmentally-aware and price-sensitive customers will turn their backs on brands that fail to meet their CO2 targets. Impending penalties will also sharpen the average consumer’s attention to the topic,” says Dr. Klaus Schmitz, Head of Automotive Business for Central Europe at consulting firm Arthur D. Little.
Battery Electric: optimization and investment potential
The greatest expectations are currently being placed on electric drivetrains. “Battery-powered cars are good, but not suitable for all requirements,” states Bert Hellwig, Electromobility Specialist at ZF. Aside from high costs, reasons include the high battery weight, coupled with extremely low energy content in terms of mass, which thus results in relatively short ranges. In compact models such as the BMW i3, the battery weighs around 300 kilograms. In mid-size SUVs such as the Audi e-tron, Jaguar I-Pace, Mercedes EQC and even the Tesla Model S, the battery can weigh twice as much. Plans at Toyota envisage a solid-state battery ready for series production in just a few years. This should be able to store more energy at considerably less weight. A specific launch date is yet to be mentioned by the Japanese manufacturer.
Batteries are also criticized for their so-called CO2 rucksack, due to the masses of energy consumed in their production. For large electric vehicles with bigger, more powerful batteries, this rucksack is significantly larger than that of smaller vehicles. However, once environmental impacts are considered over the entire lifecycle of a vehicle – including manufacturing, use over 200,000 kilometers and end-of-life processing – the scale tips in favor of the BEV (Battery Electric Vehicle) over time. This is according to Mercedes-Benz, which identified the trend in their “Lifecycle Compact” study. The Stuttgart-based vehicle manufacturer compared the environmental sustainability of its vehicles with the environmental impact of various drivetrain concepts over the duration of their entire life cycle. Calculations took raw material extraction, manufacturing, use and recycling into account. According to this, the battery-electric models – based on an average mileage of 200,000 kilometers – hold an advantage over conventional drives in terms of CO2 emissions. Even with today‘s EU electricity mix, they account for around 45 percent of total emissions, and therefore the higher energy demand in production is cancelled out. “The optimization of battery technology and manufacturing offers great potential for further savings,” says Jochen Hermann, Head of CASE (Connected, Autonomous, Shared, Electric) Development and eDrive Development at Mercedes-Benz Cars.
However, Volkswagen is currently leading the charge in the field of electric vehicles. The Wolfsburg-based company lay the groundwork in 2016 with the development of a completely new architecture, designed exclusively for battery-electric powertrains. So far, Volkswagen has invested around seven billion Euros. From 2020, the platform – named MEB (Modular Electric Drive Matrix) – will not only be used across the group for the VW, Audi, Seat and Skoda brands to achieve the desired economies of scale, but also be available to other brands as an open architecture. Ford was recently the first to seize the opportunity to use the MEB and is now developing a compact electric car for the European market on its basis.
- 80 new electric models on the market by 2025 – this is VW’s goal
Hydrogen Fuel Cell: promising technology
Hydrogen Fuel Cell. Illustration: DEKRAAn interesting alternative to the battery-electric car remains the fuel cell drive. Indeed, in terms of environmental impact, it posts similarly good values. Inside a fuel cell, electricity is produced by combining Hydrogen and Oxygen, which then drives an electric motor. The sole emission product is water vapor. Hydrogen is considered an ideal storage medium and can be separated off directly from water with the aid of renewable energy or can also be extracted from sewage sludge and biomass. In addition, motorists hardly need to change their usage behavior at all, as the refueling process takes only a few minutes, just as with diesel or gasoline. “In the long term, fuel cell vehicles will prevail,” believes ZF expert Hellwig.
McKinsey‘s “Scaling up Hydrogen” study – commissioned by the Hydrogen Council at the end of 2017 – shows that by 2050, Hydrogen could cover almost 20 percent of global energy needs.
Setting the pace with this technology is Toyota, followed by Mercedes-Benz and Hyundai. All three brands already have fuel-cell-driven production vehicles on the market. At Toyota, Hydrogen plays a key role. “Fuel cell vehicles represent the most promising way to achieve the environmentally friendly car,” says Yoshikazu Tanaka. The Chief Engineer of the Toyota Mirai sees Hydrogen as the best alternative to diesel, especially for commercial vehicles. This is because a fuel cell powertrain occupies significantly less space and weight than a battery system with the same range. Two and a half years ago, Toyota started a pilot project with truck manufacturer Kenworth at the port of Long Beach. According to the company, the two US fuel-cell powered trucks have since covered more than 22,500 kilometers locally, without any emissions and in almost complete silence. At the end of 2019, the next generation Fuel Cell Electric Truck (FCET) will be launched. The fuel cell technology of this truck stems from the Mirai sedan. Hyundai and Swiss energy company H2 Energy formed the joint venture “Hyundai Hydrogen Mobility” in April 2019, with the intention of introducing a total of 1,600 fuel cell electric trucks, mainly in Switzerland, by 2025.
The benefits of Hydrogen and fuel cells can also be realized on rails. In the German state of Lower Saxony, a regional train with a Hydrogen fuel cell powertrain has been ferrying commuters on a branch line without overhead lines in the Elbe-Weser rail network since September 2018. Lower Saxony’s Public Transit Authority (LNVG) has – by deploying the Coradia iLint of French railway company Alstom – launched the world‘s first Hydrogen-powered regular passenger train service. “The future of diesel is now a thing of the past, while Hydrogen still has its entire future ahead of it,” says Rainer Peters, spokesman for LNVG. In 2021, a permanently installed Hydrogen filling station is to enter operation and Alstom will supply a further 14 Hydrogen trains to the LNVG.
- 1839 saw British physicist and lawyer Sir William Grove deliver the first proposal to generate electrical energy through the oxidation of Hydrogen
Synthetic Fuels: tailor made fuels
Synthetic Fuels. Illustration: DEKRAAnother approach to reducing CO2 would be to increase the variety of energy sources used. Today, more than 96 percent of vehicles employ conventional engines powered by fossil or petroleum-based fuels. So, what could make more sense than to make synthetic, CO2 neutral gasoline and diesel? This could be achieved through the use of either renewable Hydrogen or organic waste. Synthetic fuels, also known as e-fuels, can in principle be tailor-made at the molecular level and thus burn far cleaner than their refined counterparts. The greatest hurdle so far is the high cost of production. Nevertheless, e-fuels could become the next big thing in the transport sector and make an immense contribution to climate protection, states a study by the German Energy Agency (dena). According to the study, over 70 percent of the energy needs of all modes of transport in the EU – including trucks, ships and aircraft – will be covered by e-fuels by 2050.
Natural Gas: renewable energy generation
Natural Gas. Illustration: DEKRAContributing to the remaining 30 percent is natural gas. Compressed natural gas (CNG) engines emit around 20 percent less CO2 and up to 95 percent less nitrogen oxides (NOx) than diesel and gasoline. Further, virtually no soot particles are emitted by comparison. The energy balance of synthetically produced natural gas is almost CO2-neutral. For example, this can be generated with renewable electrical energy, with Hydrogen as an intermediary stage. Audi is going this way. The Ingolstadt-based firm has been feeding their e-gas into the German natural gas grid for over five years. It is generated by their own power-to-gas plant in Emsland. Power is supplied by wind turbines.
Another way of producing fossil natural gas alternatives is by using organic waste. This produces bio-methane, which too could be efficiently integrated into existing infrastructure. “Refueling with bio-CNG makes vehicles almost climate-neutral,” says Stephen Neumann, Volkswagen Group Representative for CNG mobility. According to bioenergy producer Verbio, 23 percent of gas in the German grid is currently biogas generated from waste. “This would allow the existing fleet of approximately 100,000 CNG-powered vehicles to be supplied completely with bio-CNG,” says Ulrike Kurze, Marketing Manager at Verbio.
Despite this, CNG is considered the problem child of the auto industry. Despite a wide range of models available – the Volkswagen Group alone offers 19 CNG-powered vehicles – motorists have reservations about the gas technology. “Only four percent of potential buyers consider these fuels attractive,” reveals the study “Autotrends 2018,” performed on behalf of Creditplus Bank. Some baulk at the prospect of having a 700-bar pressurized tank under the car, others worry about the thin supply network across Europe – with the exceptions of Italy and Germany. In addition, the higher price when compared to a gasoline car makes CNG vehicles a less-than-tempting prospect for many consumers. “But in practice, fuel savings of 34 percent compared to diesel vehicles and 49 percent compared to gasoline vehicles are possible,” states Seat. The Spanish Volkswagen subsidiary is intensifying its efforts with CNG.
Bioethanol: production process in the spotlight
Bioethanol. Illustration: DEKRABioethanol could have an even more reductive effect on CO2 emissions. Europe would need to follow the example of Brazil, not only mixing the alternative fuel to ten percent (E10), but also offering it as a pure fuel (E100). In the South American country, pure ethanol is available at around 32,000 filling stations. However, using this does require certain technical alterations to the engine. Further, in order for ethanol to make a positive contribution to the energy balance, as little energy and water as possible must be consumed during the production process, the cultivation of biomass must be free from nitrogen fertilizers and pesticides, and land usage must not necessitate the clearing of new space.
- 1860 was the year that Nikolaus August Otto used Ethyl alcohol (Ethanol) as a fuel for the prototype of his combustion engine
Focus on alternative powertrain concepts
Batteries, Hydrogen, e-fuels, natural gas or ethanol: Which alternative energy source will ultimately prevail as the powertrain of the next decades remains difficult for even experts to predict. “This is heavily dependent on technical progress and regulations, and is therefore subject to uncertainty,” says Dr. Klaus Schmitz. The Automotive expert at Arthur D. Little also sees governmental support as a highly relevant factor. “Subsidies and regulations have a decisive influence on the dissemination of technologies,” says Schmitz, explaining: “While in Germany, these are more likely to be climate driven, in China, for example, there is a very consistent industrial policy. It is no wonder that the Middle Kingdom has become the largest market for electric cars, and it isn’t likely to relinquish this position over the long term.”
Illustration: DEKRA