#1 cleantech news, reviews, & analysis site in the world. Subscribe today. The future is now.


Published on January 16th, 2012 | by Breath on the Wind


A Short Tale & “The Long Tailpipe”

January 16th, 2012 by  


Considering all of our present renewable energy generation, there is enough clean electricity to power just a little over 100 million electric cars, today. Arguments like “the long tailpipe” would suggest that this goal is far off or even potentially unreachable.


Much of the discussion that also came with the EV1 was that the electric car was a ZEV (zero emission vehicle). The “long tailpipe argument” was used to counter that claim and, with the demise of the EV1, gained some legitimacy. It says that, even though the vehicle does not produce emissions in its operation, when charging a vehicle battery, the electric power comes as a mix that includes electricity from dirty power plants. Statistics and charts on the “energy mix” of an area are compiled for every country and political subdivision, of course. For the 12 months up to September 2011, the EIA gives the US stats as:

  • COAL: 1,788,203 (43.28%)
  • LPG: 17,423 (0.42%)
  • P. COKE: 12,911 (0.31%)
  • N. GAS: 999,811 (24.20%)
  • OTHER GASES: 11,059 (0.27%)
  • NUCLEAR: 789,649 (19.11%)
  • HYDROELECTRIC: 319,363 (7.73%)
  • OTHER RENEWABLES: 187,655 (4.54%)
  • PUMPED STORAGE: -5,838 (-0.14%)
  • OTHER: 11,581 (0.28%)
  • TOTAL: 4,131,818 GWhr (100.00%)

(I have calculated percentages from the information.)

This seems to imply that almost half of the energy put into a single electric car from the grid uses dirty coal for a little more than 2/5 of its energy.


It is really just a model. We use models to describe things that are usually too big to see all at once. A doll house could be a model of a full-sized house. We calculate the average weight and height of all people and this allows us to see where we fit into the bigger picture. But, when we do this, the individual is part of the larger group. The individual electric car is never a part of the energy-producing group. Instead, it is part of a different group. An energy-consuming or ‘using’ group. It is unlikely that we could ever find any electric car using this exact mix of energy and, if we could, is it even telling us any useful information about the car? In another place, the inference will completely change. If charging from a PV array, the model is completely useless. Our models should give us consistent information.


Fooling Perspective

Even images can fool the eyes. At first glance, we think we understand what is in front of us. In a similar way, models can sometimes give us the wrong impression. When we relate the cleanliness of an electric car to a power plant, it suggests we judge the vehicle for the problem of the power plant. This is a little like imposing the sins of the father on the son: “if your father is a racist, you must be a racist.” Neither the son nor the EV can then ever be better because they are being judge by the setting and not their merits. Once we allow this kind of argument, where do we stop the trail of blame? Other counter arguments have been proposed and I hope some will take the time to mention their impression of them in the comments section, but these all require information external to the simple argument itself.



The energy mix is useful information. It tells us about our energy supply. If we want to consider how it relates to our energy usage, we may need to also examine the energy usage in groups, as well. There are 300 million vehicles in the US. It has been suggested that we should have 1 million cars electric cars on our roads by 2015. If we reach that goal, we will have achieved an electric vehicle penetration into the market of about 1/3 of 1%.

The EPA estimates that the Nissan Leaf will need 34 kWh / 100 miles. Using an average annual mileage of 12,500, we would need (34 x 12500/100=) 4250 kWh/yr. As a brief review, 1000 watts = 1 kilowatt (kW), 1000 kW=1 megawatt (MW) and 1000 MW = 1 gigawatt (GW.) Assuming even 5000 kWhr / year, our Leaf is then using 5 MWhr/year or .005GWhr/yr).

1 million Leaf-sized vehicles may ultimately need 5000 GWhr/year, if we achieve that goal in 3 years. This sounds like a lot of energy, but it is about equal to the pumped hydro storage in the US and is dwarfed by the 187,655 GW that were produced by “other renewable energy” (wind, solar, geothermal…) in the 12 months before September 2011.

When we consider all of our presently renewable energy (conventional hydroelectric’s 319,363 GWhr plus these other renewables 187,655 GWhr) for a total of 507,018 GWhrs, we have enough clean energy to power just a little over 100 million electric cars. Now. Today.

If our entire transportation fleet of 300 million vehicles were electric, it may require an electric power supply no more than 1/3 above what we presently use.


These basic energy calculations do not consider the vast amounts of electricity that are presently used by refineries to make the fuel that goes into petrol cars.

They also don’t consider studies that suggest up to 84% of our present fleet of vehicles might be charged using the present infrastructure (no new plants) if they were charged off-peak, at night.


The long tailpipe argument is a story that is simple. It is like a tune that catches in our heads and just doesn’t seem to go away. As more people sing, it becomes increasingly popular. But it is nevertheless a model that has misdirected our eyes and fools our reason.

ZEV refers to a “vehicle.” It is a term made up by laws in the ’90s and, like other legal terms, is narrowly defined. In this case, it is based on the emissions of a vehicle. We might otherwise be asking about a zero-emissions transportation system or a zero-emissions power plant. Power plants are not vehicles. ZEV may suggest more as a common definition, but car advertisements have suggested more than steel, glass, and fabric for decades. The objection to the term “ZEV” might laughably be “the pot calling the kettle black” if it were not taken so seriously.


The lack of a direct connection between electric vehicles and power plants does not free us from our polluting, petrol-burning fleet, refineries, or electric power plants that are used for so many of our other needs. The electric car is like the pure angel that has come to tell us that there are problems that we need to discuss. The EV is not the problem but a messenger that points to some other, real issues. We can choose to kill the messenger and bury our heads in fracking, tar sands, and lots of discussion, but this will probably not give more insight or wise solutions. Thanks in advance for your considered comments below.

Devil with a short “tale”: wiki commons
EV charging: Quinn Dombrowski via Flickr
Energy mix Chart: author
Fooling Perspective: Wiki Commons
Angel: LocalTravelPhotos via Flickr

Tags: , , , , , , , , , , , , , , , , , , ,

About the Author

We share this World; its past, present resources and our combined future. With every aspiration, the very molecules we use for life are passed to others through time and space so that each of us may be considered a Breath on the Wind. This part of the world's consciousness lives in NYC; has worked in law, research, construction, engineering; has traveled, often drawn to Asia; writes on Energy and Electric Vehicle issues and looks forward to all your comments.   "If you would persuade, you must appeal to interest rather than intellect." -- Benjamin Franklin

Back to Top ↑