- Original Paper
- Open Access
Environmental and economic effects of widespread introduction of electric vehicles in Greece
© The Author(s) 2014
- Received: 5 February 2014
- Accepted: 24 April 2014
- Published: 9 May 2014
The scope of this paper is to present the results of the Project HyTech, which aimed, amongst other objectives, to quantify the environmental and economic effects of generalized introduction and use of electric vehicles in Greece.
The expected energy consumption and life cycle economic and environmental cost of electric vehicles for the present and immediate future is estimated after a relevant literature review. The future evolution of the Greek vehicle fleet relative to the Gross Domestic Product per capita is approximated by use of a Gompertz curve. The number of new vehicles registered every year, the age composition of the vehicle fleet, the resulting Green House Gas (GHG) emissions and energy use costs are calculated depending on a set of parameters. Choosing different sets of assumptions and calculating the resulting vehicle fleet statistics through year 2030, we investigated a number of scenarios.
The effect of market penetration by electric and hybrid vehicles and the resulting benefit on energy use cost and GHG emissions, compared to conventional vehicles is presented for each scenario. Fuel consumption and mileage of the vehicle fleet is a major factor that determines energy use cost and GHG emissions, regardless of fleet composition. In the case of an optimistic scenario that assumes a high renewal rate for the vehicle fleet, significant EV and HEV market penetration and use of renewable energy sources for battery recharging, a reduction of 668 kT CO2 in GHG emissions and 362 million € in energy costs per year in 2030 could be achieved.
- Electric Vehicle
- LCA (Life Cycle Assessment)
Emissions of greenhouse gases attributed to the Greek passenger car fleet at the end of 2010 have increased by 54 % compared to 1990 , in spite of the technological advances in vehicle technology. This is mainly due to the increase of the fleet size, which has tripled during the same period. The increase of the market penetration of electric vehicles is one factor, which could help achieve the necessary reduction of GHG emissions targeted by EU policies and to reduce the environmental and economic impact of the passenger car fleet.
The scope of this paper is to present the results of Project HyTech, which aims, amongst other objectives, to quantify the environmental and economic effects of widespread introduction and use of electric vehicles in Greece. In the framework of this project, we have compiled relevant data from international and Greek sources in order to determine the current situation and predict the future development of the environmental and economic impact of the Greek passenger car fleet based on a number of assumptions and parameters.
2.1 Characteristics of the passenger vehicle fleet
At the end of 2010, there were 5.2 million passenger vehicles in circulation in Greece, resulting to a vehicle density of 458 vehicles per 1000 inhabitants  which approaches the average figure for the European Union, which was 473 vehicles per 1000 inhabitants in 2009 . The number of vehicles has increased by 204 % between 1990 and 2010 and the average age of the fleet is 10.5 years , with 24 % of the fleet comprising vehicles older than 16 years, manufactured before the adoption of the EURO emission standards . Vehicle age is a major factor contributing to poor environmental and economic performance of a vehicle fleet .
The high average age of the fleet is attributed to low rates of vehicles scrapped, except for periods when the scrapping of old vehicles was promoted by economic incentives given by the government for the purchase of new cars (1991–92, 2009, 2011–2012), as presented in Fig. 1. In the last two years (2011–2012) for the first time the vehicle fleet has contracted by nearly 1 %, owing mainly to the very low sales of new vehicles due to the economic crisis and the increased taxation of vehicle ownership.
2.2 Energy consumption–GHG emissions
Total and average CO2 emissions attributed to passenger car fleet in Greece
2.3 Fuel Cost
The large reduction of mileage and fuel consumption after 2009 is, unfortunately, not a result of environmental or public transport policies but is directly related to the recent economic crisis in Greece. Taxes imposed on fuels have risen significantly in 2010 and combined with the reduction of the available income have resulted in a sharp decline in fuel consumption. Fuel taxes are a significant source of state revenue and in 2010 the state has collected 3.5 billion Euros in taxes attributed to the fuel consumption of the passenger car fleet (Fig. 3). The average operational fuel cost of the fleet in 2010 was 10.34 €/100 km compared to 6.40 €/100 km in 2000.
2.4 Import cost of new vehicles
Since no passenger vehicles are produced or assembled in Greece, all new passenger cars are imported. New vehicles (EURO 5) are subjected to import taxes ranging from 5–50 % depending on the cylinder capacity of the engine and 23 % VAT. Used vehicles are subjected to heavier import taxation depending on their EURO emission classification.
3.1 Production phase
Manufacturing of Electric Vehicles requires increased energy and material usage, mainly due to the requirements of battery production. Energy requirements for Li-ion battery production are estimated at 1,700MJ per kWh of battery capacity . A review of battery life cycle analysis , has shown manufacturing energy requirements of 2,680MJ/kWh for NiMH, 580MJ/kWh for PbA, 1,820MJ/kWh for NiCd, 1,800MJ/kWh for Na/S and 1,680 for Li-ion battery technologies.
The economic cost of Li-ion battery production is estimated at 380–450 €/kWh, with prospects to be reduced to 300–350 €/kWh until 2020 and 250 €/kWh after 2020, if the necessary economy of scale is achieved .
So, for an EV with 30 kWh of installed battery capacity, this results to additional embedded CO2 production emissions of 3.6–5.5 tCO2e and an increased production cost of 12,500–15,500 € compared to a conventional vehicle. According to a life cycle analysis of various vehicle types , the embedded production CO2 emissions of a Mid-Size EV are 8.8 tCO2e and account for 57 % of its lifecycle emissions compared to 5.6 tCO2e of a Mid-Size Gasoline Vehicle, which account for 25 % of its lifecycle emissions. A report based on the projections of major automotive manufacturers  has concluded that the cost of Electric and Conventional vehicles is expected to converge around 2025.
3.2 Use phase
3.2.1 Tank-to-wheel energy consumption
Electric Vehicles benefit from the increased efficiency of the electrical drivetrain. Conversion of energy from batteries has an efficiency ratio of 85–92 % and the electrical drivetrain has an efficiency ratio of 85–87 % [3, 19, 33]. Also, kinetic energy is recovered during the braking phase, increasing the total efficiency of the EV. The total efficiency ratio of an EV (Tank-to-Wheel) is estimated at 58–62 % compared to 16–22 % of a conventional ICE vehicle .
The major drawback of the EV remains the weight of the battery pack, needed to ensure a practical range for the vehicle. Energy density of batteries at present is 100–130 Wh/kg with prospects to be increased to 180 Wh/kg until 2020 [3, 10, 22].
Review of energy consumption of Electric Vehicles
Range as pure electric (km).
3.2.2 Electricity grid well-to-tank analysis
Electric Vehicles and Plug-In Hybrid Electric Vehicles/Extended Range Electric Vehicles, when operated purely on battery power, are locally Zero Emission Vehicles. GHG emissions depend on the fuel mixture used by the electricity production process of the grid that is used to charge the batteries.
Electricity production in Greece largely depends on lignite (a type of coal) for the 46 % of the energy produced. As a result of the low calorific value of lignite, the steam-electric power plants using it show a high GHG intensity of 1,000 gCO2/kWh with a prospect of reduction to 900 gCO2/kWh after plant modernization . Modernization of lignite plants is also needed to reduce the high emissions of SO2 and NOx, by using desulfurization methods and installing modern air filters.
In recent years there was an effort to increase the share of natural gas power plants and renewable energy sources in the electrical grid fuel mixture. Present estimations for the CO2 intensity of the Greek electricity production vary between 650 gCO2/kWh , 729 gCO2/kWh  and 846 gCO2/kWh  and it is predicted to be reduced to 530 gCO2/kWh by 2020 . According to the RetSceen energy analysis software the baseline GHG emission factor for the electricity system of Greece is 718 gCO2/kWh .
The EU27 average in 2010 was 467 gCO2/kWh and is predicted to be reduced to 365 gCO2/kWh by 2020 . Average retail cost of household electricity in Greece in November 2011, was 0.1403 €/kWh to 0.1623 €/kWh depending on the total level of consumption .
3.2.3 Well-to-wheel analysis of electric vehicle emissions
Comparison of emissions and use cost based on current electricity and fuel prices in Greece
WTW emissions (gCO2/km)
Cost (per 100 km)
Chevrolet Volt (electrical)
Chevrolet Volt (ICE)
6.3 lt/100 km
Toyota Prius (HEV)
4.7 lt/100 km
6.6 lt/100 km
6.9 lt/100 km
7.9 lt/100 km
EU average CO2 target 2012
5.63 lt/100 km
EU average CO2 target 2020
4.11 lt/100 km
3.3 Life-cycle evaluation
Life Cycle analysis parameters
7.5 l/100 km
5.2 l/100 km
6.7 l/100 km
20.4 kWh/100 km
20.8 kWh/100 km
24.9 kWh/100 km
EREV (electrical usage)
17.8 kWh/100 km
10.6 kWh/100 km
3.3 kWh/100 km
EREV (ICE usage)
0.6 l/100 km
2.6 l/100 km
6.0 l/100 km
4.6 l/100 km
4.2 l/100 km
4.9 l/100 km
Electric grid GHG intensity
Life cycle mileage
The data presented for the production phase emissions includes other GHG emissions, like CH4 and NO2 and is given in CO2 equivalent units (CO2e). For the use phase, we can assume tailpipe CO2e emissions are equal to CO2 emissions since the emissions of other GHG gases are small .
The EV and EREV perform similarly with the HEV, if we assume they are charged by a medium GHG intensity electrical grid (450 gCO2/kWh), with the EV having slightly lower total Life-Cycle emissions. Also the EV has much more potential for further emission reduction if it is charged by renewable energy sources or for energy consumption reduction as a result of improvements in battery technology.
In the framework of project HyTech, we estimated the future evolution of the environmental and economic impact of the Greek passenger car fleet by compiling different scenarios on the basis on a number of assumptions and parameters. The effect of market penetration by electric and hybrid cars and the resulting benefits on energy use cost and GHG emissions, compared to conventional ICE cars were calculated for each scenario.
4.1 Evolution of vehicle fleet size
For many reasons (economic crisis, high level of taxation etc.), it is clear that the passenger car fleet in Greece is not going to expand with the same rate as in the previous decade. A prediction for the rate of sales of new cars is essential in order to estimate the number of possible EV and HEV that can be introduced in Greece in the next decades.
Car ownership can be directly linked with the national per capita income [6, 20, 17]. Every country has a different behaviour, depending on urbanization, transport infrastructure and motoring culture but it has been shown that empirically the relationship between vehicles per 1,000 residents and GDP per capita can be approximated with the use of a Gompertz function .
4.2 Fleet age composition and EV-HEV market penetration
Fleet age composition depends on the ratio of end-of-life vehicles that are withdrawn from circulation versus vehicles entering circulation. As we can see in Fig. 1, from 2001 to 2008 this ratio in Greece was steady around 20–25 % but this was increased to 45–55 % in 2009–2010 mainly due to economic incentives provided by the state and the drop in sales of new cars. The ratio was increased over 100 % at 110–150 % in 2011–2012, which meant that for the first time vehicles exiting the fleet were more than new vehicles, but this should be treated as an exception not expected to be repeated if the economic situation stabilizes. For our scenarios we will assume that 20 % is the low and 60 % is the high-expected ratio of withdrawal of end-of-life vehicles.
Market penetration of EV and HEV in Greek market depends on global factors, as the widespread introduction of new EV models, the reduction of their cost and the improvement of range, as well as national factors, mainly the development of the charging infrastructure and the support of EV circulation with economic or other incentives. According to various announcements and commitments by governments and automotive manufacturers , the objective for 2030 is to achieve market penetration of 20–30 % for HEV and 5–10 % for EV.
4.3 Energy consumption–emissions and energy cost
The next step was to choose the low and high expected values for energy consumption and emissions. The energy consumption of EVs was assumed to be reduced from 0.18–0.22 kWh/km in 2015 to 0.15–0.19 kWh/km in 2030. Similarly, CO2 intensity of electricity production in Greece is expected to be 500–620 gCO2/kWh in 2015 and 350–520 gCO2/kWh in 2030. We also assumed a “very low emission” scenario where EVs are charged exclusively from renewable sources.
For HEV we assume emissions to be reduced from 95–110 gCO2/km to 75–90 gCO2/km, and for conventional vehicles from 120–150 gCO2/km to 90–110 gCO2/km in 2030 based on EU targets.
Expected mileage for the vehicle fleet is difficult to predict. From 2009 to 2011 a reduction of 25 % was observed based on fuel consumption. The average mileage of a passenger vehicle is expected to be reduced from 10,200–11,500 km in 2015 to 9,600–10,500 km in 2030, as vehicles per inhabitants increase.
Finally, energy cost is associated with global fuel prices, which is very volatile and unpredictable. However we can assume that there will be a long-term increasing trend. We expect gasoline price to increase from 1.56–2 €/lt in 2015 to 1.75–2.20 €/lt in 2030 and electricity prices from 0.14–0.17 €/kWh in 2015 to 0.18–0.26 €/kWh in 2030.
4.4 Scenario parameters
Scenario parameters for the calculation of environmental and economic impact
End-of-life vehicle withdrawal rate
EV – HEV market penetration
Price of new vehicles
Electricity CO2 intensity
HEV - CV CO2 emissions
very low (renewable)
Three basic scenarios were created for the evolution of vehicle fleet size and composition, based on end-of-life vehicle withdrawal rate, EV-HEV market penetration and new vehicle prices. Scenario 1 assumes that the price of new vehicles will be high and therefore fleet renewal rate and market penetration of EV-HEV will be low, while Scenario 3 assumes the opposite. Scenario 2 assumes medium figures for fleet renewal and market penetration of EV-HEV.
For every basic scenario, three sub-scenarios were considered, based on EV, HEV and conventional vehicle–energy consumption, CO2 intensity of electricity production, fleet mileage and fuel—electricity prices.
4.4.1 Scenario 1
According to Scenario 1, there will be 2.5 million new vehicles inserted in circulation and 670 thousand old vehicles withdrawn until 2030. The increase of the fleet size and low rate of withdrawal of end-of-life vehicles will result in an increase of the average age of the fleet from 11.08 years in 2010 to 16.43 years in 2030, with more than 5 million vehicles being in circulation for more than 15 years. EV and HEV market penetration is assumed to be low, with 40 thousand EV and 130 thousand HEV being in circulation in 2030.
Sub-scenario 1a, assumes that fuel consumption of new conventional and hybrid vehicles, fleet mileage and fuel prices will be high, while scenario 1b assumes they will be medium and scenario 1c low. Consumption of EV and CO2 intensity of electricity production are assumed to be medium in all 3 sub-scenarios.
The yearly reduction of CO2 emissions in 2030, attributed to the introduction of EV and HEV, is 92 kT CO2 for scenario 1a, 81 kT CO2 for scenario 1b and 65 kT CO2 for scenario 1c.
The yearly economic benefit in 2030, from decreased energy consumption is 76 million € for scenario 1a, 57 million € for scenario 1b and 39 million € for scenario 1c.
4.4.2 Scenario 2
According to Scenario 2, there will be 3.1 million new vehicles inserted in circulation and 1.3 million old vehicles withdrawn until 2030. The medium rate of withdrawal of end-of-life vehicles will result in an average age of the fleet of 15.59 years in 2030. EV and HEV market penetration is assumed to be medium, with 100 thousand EV and 300 thousand HEV being in circulation in 2030.
Sub-scenario 2a, assumes that fuel consumption of new conventional and hybrid vehicles, electricity consumption of EV and CO2 intensity of electricity production will be high, while scenario 2b assumes they will be medium and scenario 2c high. Fleet mileage and fuel prices are assumed to be medium in all 3 sub-scenarios.
The yearly reduction of CO2 emissions in 2030, attributed to the introduction of EV and HEV, is 141 kT CO2 for scenario 2a, 189 kT CO2 for scenario 2b and 233 kT CO2 for scenario 2c.
The yearly economic benefit in 2030, from decreased energy consumption is 106 million € for scenario 2a, 136 million € for scenario 2b and 146 million € for scenario 2c.
4.4.3 Scenario 3
According to Scenario 3, there will be 3.7 million new vehicles inserted in circulation and 1.9 million old vehicles withdrawn until 2030. The high rate of withdrawal of end-of-life vehicles will result in an average age of the fleet of 14.75 years in 2030. EV and HEV market penetration is assumed to be medium, with 300 thousand EV and 630 thousand HEV being in circulation in 2030. This scenario is the most optimistic, regarding the renewal of the fleet and the market share of EV and HEV.
Sub-scenario 3a, assumes that, electricity consumption of EV and CO2 intensity of electricity production will be high, while scenario 3b and 3c assumes they will be low. Especially for scenario 3c, it is assumed that EV will be charged from renewable sources. Fuel consumption of new conventional and hybrid vehicles, fleet mileage and fuel prices are assumed to be medium in all 3 sub-scenarios.
The yearly reduction of CO2 emissions in 2030, attributed to the introduction of EV and HEV, is 385 kT CO2 for scenario 3a, 526 kT CO2 for scenario 3b and 668 kT CO2 for scenario 3c.
The yearly economic benefit in 2030, from decreased energy consumption is 334 million € for scenario 3a, 362 million € for scenario 3b and 362 million € for scenario 3c.
4.5 Future scenario analysis conclusions
Regarding environmental impact we calculated the total Well-to-Wheel CO2 emissions and the benefit of EV-HEV penetration when compared to equal number of conventional vehicles they replace and regarding economic impact, we calculated the total cost of energy consumed by the Greek passenger vehicle fleet and the benefit of EV-HEV introduction.
In the case of scenario 1, the influence of fuel consumption and mileage on the final results is evident, regardless of fleet composition. The low fuel consumption and mileage scenario 1c shows similar emissions with the optimistic scenario that assumes high rates of fleet renewal and high EV-HEV market penetration. For scenarios 2 and 3, medium values were selected for fuel consumption and mileage, in order to compare the influence of other parameters. The environmental benefit is primarily attributed to the fleet renewal rate and the EV-HEV market penetration and secondarily to EV-HEV energy consumption and electricity production CO2 intensity.
The introduction of Electric and Hybrid vehicles in the Greek passenger vehicle fleet shows clear potential environmental and economic benefits, mainly due to reduction in energy consumption. Especially in the case of EV the reduction in operational cost could be important, with the increased initial purchase cost being a significant drawback. The convergence of EV-HEV initial purchase cost with conventional vehicles, as a result of technological advances or public policies will accelerate the market penetration of EV and HEV.
Project HyTech was jointly funded by the EU and Hellenic Republic and was coordinated by the Vehicles Laboratory of the National Technical University of Athens.
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