Environment

From Apterawiki

The Aptera's effects on the environment are wide ranging and described here.

[edit] Long tailpipe argument

It is sometimes claimed that electric cars are just as polluting as gasoline engines (or even worse), because the electricity is still generated by fossil fuel burning power plants. Thus, BEVs and plug-in hybrids are just shifting the pollution to somewhere else, often far enough away that the consequences are not felt by the driver. However, battery electric vehicles are significantly more efficient than internal combustion engine vehicles, so less fuel energy is needed. This is especially true of the Aptera, since it is more than twice as efficient per mile as even the EV1.[3] Also, it is far more economical to install pollution control mechanisms like scrubbers or CO2 sequestering at a few thousand power plants than to install them on millions of automobiles. As the energy mix from electricity transitions to a post-fossil economy (wind, solar, geothermal, etc), BEVs automatically transition with it. Finally, any pollution emitted by power plants occurs at altitude in less densely populated areas, while vehicle emissions occur at ground level, most commonly in populated areas.

[edit] Systemic Efficiency

See also fuel efficiency

Energy efficiencies of different propulsion methods gathered in "Well to wheel study of passenger vehicles in the Norwegian energy system"[1]. Note the unimpressive performance of hydrogen cars (PEMFC and ICE H2), gasoline cars, and diesel cars, and the excellent performance of electrics.

CO2 and NOx emissions from different propulsion methods, gathered in "Well to wheel study of passenger vehicles in the Norwegian energy system"[2]. Again, note the unimpressive performance of hydrogen cars (PEMFC and ICE H2) running on ordinary power, gasoline cars, and diesel cars, and the excellent performance of electrics.

Internal combustion engines are generally quite inefficient -- generally a ~20% tank to wheel efficiency[4] and even lower for well to wheel. Hybrid vehicles can boost this as high as the 30s, but some of the benefits of hybrids apply to EVs as well (for example, regenerative braking), and we haven't accounted for the loss of energy in oil production/refining. Also, diesel engines can boost mpg by about 40%, although the fuel is about 15% denser than gasoline, so it's really only about a 25% efficiency boost.

Let us compare to the least efficient bulk fossil fuel power plants -- coal, which are not only dirty, but average only 36% efficiency[5]. Next generation coal plants are in the 40s and 50s, and natural gas plants are already that high. Transmission efficiency in the US is 92.8% efficient[6]. The AC Propulsion drivetrain, to pick one, is 86% efficient in normal use (93% recharge efficiency)[7]. Multiplying this out, we get 28.7% efficiency -- well above that of cars.

Now, we picked coal, the dirtiest of the bunch -- how do our CO2 emissions compare? Coal emits 25.4 tons of CO2 per megajoule, while oil emits only 20[8]. Scaling our efficiency down, if we were only concerned about CO2, we get a still good 22.6%. We've biased everything possible against EVs, and they still come out ahead; let's not forget that half of our power is a mix of natural gas (lower carbon than oil per joule and more efficient to boot), hydro, and nuclear, while solar, wind, and geothermal are a rapidly expanding sector. Not to mention, oil is getting dirtier and less efficient as sources switch from easy to get light sweet crude into deepwater crude, bitumen syncrude, ultra heavy crude, coal liquefaction, oil shale, and other sources.

A peer-reviewed DOE study conducted by PNL agrees with the above efficiency conclusions about EVs[9], as does this study about the Norwegian transportation system. [10]

[edit] Consumption

The above comparison was, of course, a comparison of two vehicles that use an equivalent amount of energy. The Aptera distinctly does not use an equivalent amount of energy to a normal vehicle. With its aerodynamic design and low rolling losses, a 10kWh battery pack[11] takes it 120 miles at 55mph, meaning 83Wh/mi. Most EVs, which are usually already extra streamlined, use about 200Wh/mi. Hence, the actual consumption by the Aptera is far less than the above calculations would suggest.

[edit] Other Emissions

CO2 is not the only pollutant emitted by cars and power plants. As the two studies above reveal, switching to an electric drivetrain affects other pollutants significantly. The only pollutant that would rise, given *equivalent* energy consumption (note again, the Aptera consumes far less) is particulate matter (which also rises if you switch to diesels). SO2 would rise, except for the fact that to cash in on the financial windfall to power companies that EVs would bring, to stay in compliance with the Clean Air Act, they'd also have to upgrade their scrubbers at the same time. Hence, it actually wouldn't rise in practice. Nitrous oxides remain about the same (again, assuming equivalent consumption). Carbon monoxide and VOCs are virtually eliminated. To sum up what the pollutants mean:

• CO2: Global warming and ocean acidification.
• Particulate matter: Lung disease. Both warming and cooling effects.
• SO2: Acid rain. On the plus side, it leads to global cooling.
• NOx: Lung disease, irritating. Leads to the stereotypical brown "smog" haze.
• Carbon monoxide: Does permanent heart and neurological damage
• VOCs: Lung disease, irritating, and often carcinogenic.