Vehicles (Hybrid / Electric)
Hybrid Vehicles for the Military
Today’s military forces need greater operational independence. As a result the US military is seeking ways to be more agile, mobile and extend the range of their vehicles, while cutting their fuel logistic requirements. They are developing a series of Manned Ground Vehicles (MGV) powered by a hybrid diesel/electric drivetrain. These are similar to the “Agressor,” the off-road Alternative Mobility Vehicle (AMV) announced in May 2007. These efforts and accompanying field applications should contribute valuable knowledge and possibly prod commercial interests to put more energy into developing more lightweight, efficient vehicles.
Source: Popular Mechanics
EV’s (Electric Vehicle), PHEV’s (Plug In EV) and Hybrids
Can I buy an all electric vehicle today? The options are limited. The most interesting are the Tesla Roadster (0-60 in 3.9 seconds, 135 mpg equivalent, 220 mile range per charge) at $92,000, or the more affordable Zap-X at $30,000. Unfortunately, neither is readily available.
Alternative options to the pure electric vehicle are the well known hybrids, such as the Prius. These are Hybrid Electric Vehicles (HEV) in which both the electric and gas engines drive the wheels. The car is also able to recapture energy in a number of ways, such as from braking. They do not rely upon electricity from the grid. A list of available 2008 Hybrid Vehicles and their mileage estimates are available from the EPA.
A second option is the Plug In Hybrid Electric Vehicle (PHEV) in which only the electric motor drives wheels. A small engine and generator produces more energy as needed. It has an all electric range capability without using its internal combustion engine (i.e. PHEV-20 can travel twenty miles). It is defined by IEEE as a “vehicle with a battery storage system of 4 kWh or more, used to power the motion of the vehicle; a means of recharging that battery system from an external source of electricity; and an ability to drive at least ten miles in all-electric mode, while consuming no fuel.” Currently most PHEV’s are produced by hobbyists who convert existing stock hybrids, although there are companies such as Hymotion, and EDrive that will do the conversion for you. As for the future, GM has announced a production vehicle called the Volt PHEV-40 due out in 2010.
The fact remains, however, despite high fuel costs, most car buyers are just not ready for the shift to alternative vehicle types. They want the reliability of a proven product. EV’s cannot match the mileage range of traditional gas based automobiles (300+ miles). Typical EV’s can travel a max of approx. 150 miles (or less) before recharging. The Tesla’s limit is about 220.
Infrastructure is also a big challenge. Electric vehicles seem to have the early advantage over other transportation alternatives because they relies upon 110 volt home power - which of course is already in place. However, you are not always at home. Other alternatives such as fuel replacement (i.e. hydrogen and ethanol) would require significant investment in time and money right out of the gate, even if the technology can prove its value.
Energy storage is another big challenge. Key issues are storage capacity, recharge time, size , weight and price. Early hybrids relied on lead acid batteries, but the lithium ion battery is the choice in newer designs, such as the Tesla, Zap and GM’s Volt.
There are a number of battery makers who are leading the way in developing new storage technologies to overcome some of the need for a lightweight, powerful, affordable battery. They include companies such as A123 Systems, (Watertown, MA), Altair Nanotechnologies, (Reno NV) and SAFT (France).
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