Thursday, May 1, 2008
Plug-In Hybrid Electric Vehicles--Transportation of the Future
Plug-in Hybrid Electric Vehicles have brought together a multitude of technologies to be considered for one of the newest forms of transportation. Driven by battery power to an electric motor, the car will run until the battery has drained to a certain capacity and then the Internal Combustion Engine will turn on to recharge the battery or power the vehicle directly. This setup can be seen in the figure on the right. The main technological restraint from this vehicle's penetration into the market is the battery.
Today batteries like Nickel metal hydride and lithium ion are being used due to their less susceptibility to the "memory effect". They can retain charge after many charge/discharge cycles. The batteries for these vehicles will need to be scaled up 3 to 5 times to provide the mileage needed by the average driver. This increase in size and power will be expensive and make these items very valuable. Design features to prevent criminals from stealing these batteries will need to be taken, unlike the situation with catalytic converters.
With federal funding, researchers have been able to look into the questions about PHEVs. Questions that dealt with topics like the environmental impact and the economic feasibility.
It turns out that with many different scenarios, Plug-in Hybrids produce less Greenhouse Gas Emissions than the Conventional Vehicle and the Hybrid Electric Vehicle. These results can be seen from the figure above on the left. These results from the Electric Power Research Institute and the Natural Resources Defense Council were able to show that the PHEV is better for the environment especially in the future when electricity generation methods are expected to become cleaner.
The public also is concerned with how they will be able to afford this more expensive vehicle. With today's gasoline prices, the savings from switching to electricity to power your vehicle can allow to pay for the extra costs in about five ten years. This is excluding the possibility of battery prices falling in the recent future.
Because of the status quo with transportation, measures need to be taken to change the path we are following. The Plug-in Hybrid Electric Vehicle will help us reduce our dependence on foreign oil, centralize our pollution source to make it easier to clean in the future, and push the edge on technologies like batteries.