Transport Economy:Hybrid Power Train – Vehicle of the Future? | |
If one were to believe TV advertising we should all sell our traditional car with a combustion engine as quickly as possible and replace it by a new vehicle with a hybrid power train.
It does not take long to explain the principle of a hybrid power train: it is a combination of a conventional economic combustion engine with an electric motor. Together they provide more flexibility for selecting the most favourable power train at a certain time. The electric motor is used for starting the car, the car will start from being stationary nearly without any noise, powered by the current derived from an efficient battery.
The advantages are obvious: the electric motor can play out its strengths with regard to energy efficiency at low speeds. The petrol engine is only switched on when the speed increases and takes over from the electric motor. Part of the energy can be recycled and stored in the battery during the drive when there is excess energy, for example whilst driving down a hill.
The manufacturers of hybrid cars are increasing all the time and offer more and more such vehicle concepts. If one were to believe the glossy brochures the introduction of the hybrid technology heralded a new era in automotive construction. Eco-friendly, energy-efficient, low noise and other attributes embellish the pages of the colourful prospects. Even large-volume SUVs (sports utility vehicles) are equipped with a hybrid power train, and the buyer thus gets the absolution from the manufacturer and won’t have to have a bad conscience in future if he uses his ATV with an empty weight of more than 2 t to drive to the supermarket.
The question remains whether the immense technical expenditure in hybrid vehicles is actually appropriate. The hybrid car plays out its strengths exclusively during city traffic and in traffic jams, where the clean electric motor is being used. For overland trips the petrol engines of the hybrid cars show an even higher fuel consumption than traditional engines. In addition there are at least compensating effects: besides a combustion engine a hybrid car drags along an electric motor including batteries, generator and complex management systems.
It may be true that the emission values can be reduced partly up to 50 %, but one must also include the emissions released for manufacturing the additional components into the emission balance. Moreover the cost price quickly becomes a reason for not buying this type of car.
The lower fuel consumption does by no means offset the higher cost price. The politicians once again also missed the chance of creating suitable incentive systems; a mere reduction of the NoVa (tax on new vehicles referring to the fuel consumption) is only a small incentive for many buyers. In connection with the immanent CO2 and particulate matter debate one must ask oneself whether the introduction of the hybrid power train can be seen as a helpless spontaneous reaction of the car manufacturers. In the mid nineties of the last century there was talk already of the introduction of really innovative concepts such as hydrogen-powered combustion engines or even of the fuel cell. But what came of both these approaches? It was sufficiently shown in numerous prototypes that both concepts do in fact function, but the implementation petered out quickly for lack of partners who were ready to invest. But the main problem can be summarized quickly: The manufacture and storage of hydrogen. There is no process for producing hydrogen in an energy and ecology efficient technical manner. And that is how the hybrid power train slowly took off on its triumphant course.
Author: Dipl.-Ing. Dr. Markus Guggenberger
