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Based on published data from various sources an economic and environmental comparison of a conventional, hybrid and electric vehicle – currently available at the Greek market – is performed. The production and utilization stages of the vehicles are taken into consideration. Three different electricity generation scenarios-high, medium and low carbon – are investigated. According to the comparison hybrid and electric cars exhibit advantages over conventional. In a carbon free electricity generation scenario the environmental benefits of electric cars are significant since 55.2% of the total Greenhouse gas emissions and 61.4% of the total Air Pollution emissions are stemming from conventional car; whereas 6.85% and 5.76% of total air emissions produced are emanating from electric car. It is shown that the environmental impact of electric car use depends on the source of electricity.

Published data from various sources are used to perform economic and environmental comparisons of four types of vehicles: conventional, hybrid, electric and hydrogen fuel cell. The production and utilization stages of the vehicles are taken into consideration. The comparison is based on a mathematical procedure, which includes normalization of economic indicators (prices of vehicles and fuels during the vehicle life and driving range) and environmental indicators (greenhouse gas and air pollution emissions), and evaluation of an optimal relationship between the types of vehicles in the fleet. According to the comparison, hybrid and electric cars exhibit advantages over the other types. The economic efficiency and environmental impact of electric car use depends substantially on the source of the electricity. If the electricity comes from renewable energy sources, the electric car is advantageous compared to the hybrid. If electricity comes from fossil fuels, the electric car remains competitive only if the electricity is generated on board. It is shown that, if electricity is generated with an efficiency of about 50–60% by a gas turbine engine connected to a high-capacity battery and an electric motor, the electric car becomes advantageous. Implementation of fuel cells stacks and ion conductive membranes into gas turbine cycles permits electricity generation to increase to the above-mentioned level and air pollution emissions to decrease. It is concluded that the electric car with on-board electricity generation represents a significant and flexible advance in the development of efficient and ecologically benign vehicles.

Electric vehicles have recently been gaining increasing worldwide interest as a promising potential long-term solution to sustainable personal mobility; in particular, battery electric vehicles (BEVs) offer zero tailpipe emissions. However, their true ability to contribute to greenhouse gas (GHG) emissions reductions can only be properly assessed by comparing a life cycle assessment of their GHG emissions with a similar assessment for conventional internal combustion vehicles (ICVs).

This paper presents an analysis for vehicles typically expected to be introduced in 2015 in two example markets (the UK and California), taking into account the impact of three important factors:

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Like-for-like vehicle comparison and effect of real-world driving conditions.

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Accounting for the GHG emissions associated with meeting the additional electricity demand for charging the batteries.

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GHG emissions associated with vehicle manufacture, disposal, etc.


This work demonstrates that all of these factors are important and emphasises that it is therefore crucial to clearly define the context when presenting conclusions about the relative GHG performance of BEVs and ICVs – such relative performance depends on a wide range of factors, including the marginal regional grid GHG intensity, vehicle size, driving pattern, loading, etc.

Highlights
► Develops new insights into the life cycle GHG emissions of electric vehicles. ► Addresses like-for-like vehicle comparison and effect of real-world driving. ► Accounts for marginal GHG intensity of the electricity used to charge EVs. ► Accounts for the GHG emissions associated with vehicle manufacture and disposal.