Right now gas prices are pretty reasonable but they are not going to stay that way. When gas prices go up people are going to once again freak out about alternative fuel. For many years there has been a lot of work and discussion around the electric car. Some of the main problems with electric cars is that the infrastructure to supply electricity to these cars is not available everywhere, they take a long time to recharge, and you cannot travel as far as gas powered cars.
I came up with the idea of changing out batteries in the cars versus recharging them. In manufacturing environments many companies use electric fork lifts. When these lifts are low on power you can trade the drained battery with one that has been sitting on the charger. Why can’t we use this concept with cars? We could convert existing gas stations with the ability to store and recharge these batteries. When your car is low on juice you pull up and change out the battery for a fresh one in about the same time it takes to fill up with gas. Trading the battery would be like trading your empty propane tank for a full one for your grill. Once the exchange is made you will be on your way. Another benefit of this is that when new battery technologies come around you can easily have it installed. Also, when your battery becomes unrechargable as many batteries eventually become it is easily to replace.
If you were to take on this idea there are concerns (business opportunities) that I see that will need to be resolved.
Standardizing the batteries for all cars or at least making the batteries standard per brand
Setting up the gas stations to replace, store and charge batteries
Creating the batteries
Shipping the batteries
There are several opportunities in this idea to create a business so take this idea and do something with it.