3 factors that drive the propulsion system of the future

The propulsion systems of the 21st century integrate internal combustion engines, batteries, transmissions, engines and sophisticated control systems. Technology has been continuously evolving since the first propulsion systems came to light in the late nineteenth century, but in recent years there have been massive changes with great rapidity. These are the result of three significant trends: the pressure to reduce fuel consumption, a more onerous regulation for toxic emissions and the electrification of vehicles.

Pressure to reduce fuel consumption

Currently, there is widespread support for reducing fuel consumption, which is why significant efforts are devoted to reducing CO2 emissions (a waste of 1 liter per 100 kilometers corresponds to 23 grams of CO2 per kilometer for an engine of gasoline and 27 grams of CO2 for a diesel engine). This is a significant factor to optimize the propulsion system itself (engine and transmission) to which are added other factors such as the transfer of functions traditionally associated with the combustion engine, to high-efficiency electric motors and lower dependence on fossil fuels.

If we review the last two decades, during the first decade there was a small, although continuous decrease, in the number of grams of CO2 per kilometer (average reduction of 1% per year). The turning point came in 2007 as the automotive sector received a wake-up call when directives were passed that established in Europe the target of 95 grams of CO2 per kilometer (equivalent to average fuel consumption of 3.8 liters of gasoline). For every 100 kilometers for the entire car park) in 2020. From this moment, the figure took a big leap to go to an average annual reduction of 4%. The pressure to reduce the CO2 emissions of the vehicle is not limited to Europe; This faster reduction of CO2 in cars is a global goal. In the U.S.A.

The target of 97 grams per kilometer has been set in 2025 (although it must be recognized that the new administration tries to annul this legislation), China wants to reduce CO2 emissions to 117 grams per kilometer in 2020, and South Korea tries to achieve 97 grams of CO2 per kilometer in 2020. As the dates set in the objectives approach, and since the reductions set for emissions are likely to remain the same, vehicle manufacturers will be put under more pressure to achieve the objectives of driving tests in which consumption and emissions are measured.

More demanding regulations for toxic emissions

In Europe, diesel cars currently represent around half of the light vehicles and their evolution is marked by the requirement of 95 grams of CO2 per kilometer. A diesel vehicle achieves better CO2 emissions than a comparable gasoline engine. However, as regards the emission of toxic gases such as NOx, CO, HC and particles, a gasoline engine obtains better results than a diesel engine. The regulations for these emissions are increasingly demanding. In Europe, for example, since the first dollar standard in 1992 and the most recent ($ 6), the limits for NOx emissions have been reduced from 0.97 grams per kilometer to 0.06 grams per kilometer for gasoline engines and 0.08 g / km for diesel engines.

The same trend is valid for particles: from 0.14 grams per kilometer for $1 to 0.0045 grams per kilometer for Euro 6 and is no longer applies only to diesel engines due to modern technology of direct fuel injection. Also, $6C was introduced earlier this year, the latest derivative of the Euro 6 legislation, which includes a set of harmonized light vehicle tests around the world and tests of actual driving emissions with a compliance factor of up to 2.1. As of 2020, the same legislation ($6D) will require a compliance factor of up to 1.5. Therefore, the most onerous regulations are undoubtedly driving the implementation of a cleaner and more efficient technology in the propulsion system.

Boom of electrification

Given that car manufacturers face much greater restrictions on emissions, they are forced to develop different propulsion systems to meet the regulatory objectives that have been established for new vehicles and the entire fleet. Many traditional fuel engines are still used around the world, but there is a clear trend in favor of hybrid and electric vehicles. For example, short-term forecasts indicate that hybrid cars will be equivalent to diesel cars today, with an expected market share of 20% in 2024.

In addition, according to KPMG's Global Automotive Executive Survey 2017, one in three consumers plans to have their next car fully hybrid. The truth is that, except for the Japanese and Californian markets, until now very few hybrid vehicles have been sold, but this will radically change during the next few years. In this sense, hybridization, and ultimately electrification, are evolving from an emerging market to a consolidated one. In addition to generating fewer emissions, the electric motor also offers significant advantages from the point of efficiency. The internal combustion engine is quite bulky; For example, a conventional motor consists of more than 200 moving parts. Compare Tesla's AC induction motor, that only has a mobile piece and has the size of a watermelon. The advantage in terms of efficiency is immediately evident as weight and energy consumption go hand in hand. With regard to heat dissipation, the energy efficiency of a gasoline internal combustion engine is about 30% (in diesel vehicles is somewhat better, 40%), the energy efficiency of electric cars is higher than 90% in the car and 60% between the electronic network and the wheels. In this sense, hybridization and electrification are the answer to achieve these challenging objectives. It will also stimulate investments in evolutionary and revolutionary technologies for propulsion systems. The energy efficiency of electric vehicles is greater than 90% in the vehicle and 60% between the electric network and the wheels. In this sense, hybridization and electrification are the answer to achieve these challenging objectives. It will also stimulate investments in evolutionary and revolutionary technologies for propulsion systems. 

Greater need for sensors and IC

The search for a lower level of consumption and emissions, spurred by the increased demand for directives and legislation, is creating a greater need for next-generation sensors and the automotive electronics industry must respond accordingly. To reduce emission levels, manufacturers of conventional internal combustion engines try to make constant improvements regarding the air intake, exhaust, fuel, ignition, thermal management and displacement. Robust, high-precision sensors for position, use of digital oscilloscope, speed, pressure and current, together with the advanced sensor connection ICs, can generate the necessary data to help vehicle manufacturers comply with this regulation. The same is true for the trend towards electrification.