Fuel consumption is a major issue in today's world. Because oil reserves are running low, we will need to cut our fuel consumption or else the cost of gasoline will only go up. Check out these great fuel consumption articles from HowStuffWorks.
The short answer is: yes. You could compress the air at your house using an air compressor fill a compressed-air tank in the car and the car could run off of it. But it's not quite that easy. Find out why.