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electric car emissions and CO2 country P.Langlois

published: 04/06/09, 10:34
by Christophe
Here is a synthetic but comprehensive and relevant analysis of CO2 emissions from electric cars and electric vehicles in general.

It can never be said enough: an electric vehicle can be competitive on the CO2 if and only if the primary energy source that produced the electricity required for its charge emits low CO2 emissions! But fortunately: there is not only the CO2 in life ...

CO2 emissions from electric cars


Often, when we talk about electrically powered vehicles, we are wondering whether transferring emissions from traditional cars to power plant emissions will really improve things about greenhouse gases.

To answer this question, we must first consider the CO2 emissions of the various networks, expressed in grams of CO2 per kilowatt-hour of electricity produced. These values ​​can be obtained via the statistics of the energy or environment ministries or departments of the different countries or states, or via the state electricity companies (EDF in France and Hydro-Québec in Quebec).

However, greenhouse gas emissions from these organizations or corporations are often those that result from the burning of fossil fuels in the power plants themselves. Emissions from oil or gas mining activities are lacking, to go underground for various fuels, including uranium for nuclear power plants. These data also do not take into account the processing of raw materials and their transport, or the construction of plants. There is also a lack of emissions resulting from the decomposition of submerged trees in reservoirs of hydroelectric dams. To account for these various aspects, a life cycle study of one kiloWatt-hour of electricity, from ground to outlet, is required. Various studies tell us, roughly, that 15% emissions must be added for petroleum and coal and 25% for natural gas. For nuclear power plants, there is usually 15 gCO2 / kWh, and 18 gCO2 / kWh should be added for hydroelectric dams. In doing so, for California, the United States, France, Canada and Quebec, the emission intensities are obtained from the following table.


Now, an electrically powered intermediate car, built in 2009 with the best commercially available technologies, consumes about 17 kwh / 100 km of electricity stored in its battery. On the other hand, with wheel motors, a lighter car and better aerodynamics, consumption should be reduced to 12 kwh / 100 km of electricity stored in the battery, say to 2020. But, to evaluate the emissions of CO2, we will assume a consumption of 15 kwh / 100 km from the electricity stored in the battery. We add 6% for the losses of the socket (alternative) to the electricity stored in the battery (continuous), which brings the actual consumption to 16 kwh / 100 km, from the power station to the wheels. To obtain the CO2 emissions of the electric car, it is sufficient to multiply this actual consumption by the emissions of the networks of the preceding table.

The results are shown on the graph at the beginning of this post. It also includes CO2 emissions from gasoline cars for comparison purposes. The 1500 kg intermediate car (thick blue line) is equivalent to the electric intermediate car for which we made the emissions calculations.

To obtain CO2 emissions from conventional cars, we assume that gasoline is fully burned, which releases 2,36 kg of CO2 per liter. The CO2 released from the oil well is taken into account in the tank of the car, adding 15%, which corresponds to the evaluations of the various studies on the subject.

It is particularly interesting that in the United States, with a fleet of plants burning fossil fuels to produce 70% of electricity (50% of coal plants and 20% of natural gas plants), CO2's of an electric car are still better than those of a car consuming 5 liters / 100 km, like a Prius. In France and Quebec, electric cars would emit much less gas than a Prius, as we can see.

Quebec appears, in fact, as a place quadruplement privileged to implement the electric mobility in America, due to

- the significant reduction in greenhouse gases that will result,

- the abundance of electricity found there and its renewable aspect,

- at its low cost (0,07 $ / kWh),

- and the very important economy on oil imports (100% of imports)

To better see the difference between the various types of power plants, the following graph shows the CO2 emissions of an intermediate electric car that we would recharge the battery with electricity from different types of plants.


The calculation method is identical to the previous graph, except for the intensity of emissions that are no longer those of the networks as a whole, at different locations, but rather the intensity of GHG emissions of the various types of emissions. central, from the ground to the socket. The following table summarizes the results obtained using the GHGenius life cycle calculator developed for Natural Resources Canada ( )


Therefore, as can be seen, CO2 emissions from electric vehicles or plug-in hybrids in electric mode are still considerably lower than those of traditional vehicles using petroleum fuels. The last chart also shows the importance of using renewable energy to drastically reduce our emissions.

Source: P. Langlois's blog

We must qualify this reasoning because I find it a little too full of excess optimism especially on the figures of 16 kWh / 100 km from the power station to the wheel (see below) and the figures of emissions of kWh in France (I had 90 g / kWh in mind).

Moreover if we must take into account the construction of plants: what about the life of the batteries still limited? In 2020 it may be different? I hope so! A director of Mitsubishi confessed that only the farbication of the batteries already issued 40g CO2 / km, see here: ... t6280.html

Equivalence between 16 kWh / 100 km and fuel consumption at equal "vehicle" efficiency

16 kWh from the power station to the wheel ca gives, according to the author, 15 kWh from the battery to the wheel (6% is already very low like various central losses -> battery but whatever).

These 15 kWh will give (90% yield) 13.5 useful mechanical kWh.

This value corresponds to the consumption with a good modern diesel engine (35% average efficiency) at 13.5 / (0.35 * 10) = 3.86 L / 100 km. It's little but realistic with a small vehicle. We thus obtain emissions of 3.86 * 2.6 = 100 gr CO2 / km and we thus pass below the bar of 114 gr / km ...

In short it is not easy to decide on the CO2 with electric propulsion but it is easier to produce electricity in the garden than to drill a well of oil ... If you know what I mean! And in a general way I think it's a mistake to limit ourselves to CO2 emissions when we talk about electric transport: are there no other pollutants whose suppression is a considerable advantage for public health?

published: 04/06/09, 13:56
by Capt_Maloche
EH! I am at 7.1 L / 100 of average at 140 with my 1680 tank kg :D and 8.xx on highway according to the manufacturer

the 1er table surely concerns minivans with a strong windward grip

Renault Vel Satis 2.0 150 DCI FAP CARMINAT 2007

ConsumptionEconomy: 9.2 l / 100 km
Mixed consumption: 7.3 l / 100 km
Extra-urban consumption: 6.4 l / 100 km
Tank: 80 l
CO2: 194 g / km E

AERODYNAMISMS (m²) / Cx 2,37 / 0,335

for a space: AERODYNAMISMS (m²) / Cx 2,8 / 0,325

there is 0.40m² of difference surface between a Vel and a space anyway

Anyway, in fact, the origin of electricity production must be "green"
A good distribution of photovoltaic panels, wind turbines and consors will achieve this goal

published: 04/06/09, 13:59
by Christophe
It mainly concerns ESSENCE cars (majority in Canada as well as in the USA).

Do not impede ME I already ride solar! Oh yes!! Image


I did not ride much but it's still solar (it's the intention that matters hihihiih)! I had to do at least ... 500 m since I finished editing! At least yes gentlemen !! : Idea:

Details here: ... 9-100.html

published: 04/06/09, 14:04
by Christophe
[Paranoic mode] And if that was what sneakily wanted to prevent politics: that we recharge our cars with solar (so intaxable and uncontrollable ... at least initially)?

To avoid this, we invented THE SUBSIDY on PV for less "annoying" use ... [/ Parano Mode]

published: 04/06/09, 14:09
by renaud67
In agreement with this bridge paranoid view: when it comes to electronics we will always find montages to make a loader, to at least partially loaded his car: what would happen, say, if he returned more than the half of the TIPP ...

published: 04/06/09, 14:14
by Christophe
So, do not worry about this! We have already talked about it and the government knows how to be VERY very inventive when it comes to setting up a taxation system !!

If you have to put a GPS tracker with a GSM link as standard to communicate in real time (or almost every 24 hours or a week) the km traveled, it will be done ... and it will be billed "later" ...

Let's have no worries about it ... only the 1er users will be privileged, a bit like all the new technologies ...

published: 02/09/09, 12:58
by Christophe
Bonnjour to all

For those who have not seen the report yesterday to RDI on electric cars, in which I participated, you can watch it offline at ... 2008-2009/

Click "Watch the full" on Thursday 6 August 2009 and advance the counter down to 4 / 5 (circled in red on the image below).

Pierre Langlois, Ph.D.

published: 23/10/09, 13:27
by Christophe
Interesting IFP interview:

August 2009

To reduce CO2 emissions and oil dependency in the transportation sector, electrified vehicles have great potential.

From simple hybrids to plug-in hybrids to all-electric vehicles, there are many configurations and they all aim for improved environmental performance.

Philippe Pinchon, Director Engines-Energy at IFP, explains why the electrification of the vehicle will be gradually increased and what will be the benefits.

What types of electrified vehicles will develop in the future?

Ph .: The outlook for the global hybrid market is estimated between 6 and 7% sales on the 2018 horizon. Different configurations of hybrid vehicles, with electric power available on board very variable, will develop. According to their respective configuration, and particularly the characteristics of their battery, the different models will have an electrical autonomy typically ranging between 5 and 200 kilometers. In the coming years, it will also be necessary to rely on purely electric vehicles for essentially intra-urban uses.
Depending on the market segment and the intended uses, the choice will be towards the solution offering the best compromise between the gains in energy consumption and the extra cost of the embedded system and infrastructure.

What are their advantages in environmental terms?

Ph .: Hybrid vehicles that combine a heat engine, an electric machine and their respective energy storage (fuel tank and battery) have a high potential for reducing CO2 emissions. This combination makes it possible to choose the optimal operating mode (thermal, electric or combined) according to the path profile, and in particular to reserve the use of the engine in its areas of good performance.

But the reduction in fuel consumption and therefore CO2 emissions depends on the degree of electrification of the vehicle: 3 to 7% for Stop & Start models which stop the heat engine when the vehicle is stationary; 20 to 35% for Full hybrid models (capable of operating in all-electric mode over very short distances, between 1 and 5 kilometers), thanks in particular to the recovery of electrical energy during braking. As for future rechargeable models on the electrical network and able to operate in all-electric mode over long distances, they could see their CO2 emissions reduced by 50 to 90% in urban use and provided, however, that the electricity is produced from 'a low carbon source like in France. Finally, with electric cars, average reductions in CO2 emissions of 50% are possible in Europe.

We must not forget that the margins of progress are very variable depending on the source of electricity used, France with nuclear power is rather well positioned.

Are there still challenges before large-scale marketing?

Ph. P .: Batteries, whose energy and power density must be increased and the cost lowered while ensuring the best safety conditions, still require a lot of R&D work. Lithium-ion and lithium-polymer batteries represent real progress in terms of on-board power compared to nickel-metal-hydride batteries. But they are more expensive and pose more security concerns.

Progress must also be made on the electric motor itself, still too expensive and not suitable for the major automobile series. Another key point is the supervisor, the true brain of the car that manages energy on board, air conditioning systems, braking and charging infrastructure. In fact, the architectures of hybrid vehicles are complex. Numerous operating modes are possible, from 100% thermal to 100% electric, including energy recovery during braking, where the vehicle's inertia recharges the battery.
The two drive systems can also be used at the same time, "in parallel", for additional power.
All this must be controlled in real time by software embedded in the onboard controllers in the vehicle so that, at every moment, the best decisions are taken to optimize the battery charge, reduce consumption and ensure the best possible approval. conduct.

What are IFP's work and skills in this area?

Ph. P.: Benefiting from key competences in motor technologies, modeling, simulation and control, IFP has undertaken important work, in partnership with industry, in the field of hybrid and electric. The research focuses on the following areas: the design of thermal engines dedicated to the hybrid vehicle, the development of control strategies to optimize the management of energy on board and to make the choice, according to the use of the vehicle, the distribution of power between the engine and the electric machine and, finally, the improvement of battery management and in particular the diagnosis of the state of charge to extend their operating range. To reduce development costs and delays, IFP has adopted an innovative approach that combines work on virtual models via computer simulation and real test facilities.

IFP participates in numerous projects in this field that bring together industrial and academic partners (ANR projects, Demonstration Fund projects of Ademe, etc.). A research platform project, which will be located near Versailles and will bring together numerous means of testing and calculations, is being set up. IFP is an important player. We are currently witnessing a real mobilization around the theme of hybrid and electric vehicles which should allow an accelerated marketing of these technologies.

Sources + links to find out more: ... lectrifies

published: 22/02/10, 11:32
by Capt_Maloche
Now that's funny :

The future is hybrid vehicles Hacked, it's crazy no?

Admittedly, for work, I can do 50 + 100km per day, rarely more, after that, there are some occasional trips of 300bornes max, if more, it will be the plane or the train.

for half, my movements are about 60Km / day

for me and many French, this electric autonomy would be sufficient, 150 would be the top

On the other hand, for a VRP or commercial, it is clearly insufficient.
Charging by a small diesel generator + would be ideal

published: 22/02/10, 11:36
by Christophe
Yes Maloche and ca they could do it easily at low prices.

1ere car = thermal
2ieme = electric

See the 1er message here: ... 3-240.html

The debate of the electric car is more POLITICAL than TECHNOLOGICAL ...

After there are still lobbyists who want us to believe that it is a technological problem VE ... I think it is polito economic :)

Why some associations do better in self-construction than protopipos of automakers?