Owning a hybrid brings gallons of satisfaction The dollars may not add up, but it still makes sense.

For eight years, I owned an oversize SUV that guzzled way more than my share of gas. I convinced myself that I needed that vehicle for its eight seat belts, being the self-proclaimed carpool queen. My family also needed plenty of packing room for our annual camping trip; a smaller vehicle just wouldn't do. But as time marched on, Al Gore made me think about my anti-green ways. Gas prices soared past $3 a gallon, and I began to feel guilty.

Finally, the time came to buy a new car. With carpooling still high on my priority list and thoughts of future family road trips, I knew a five-passenger car wasn't going to cut it. After visits to several dealerships and much deliberation, I decided that we still needed an SUV, but that we would get a hybrid. It would be more environmentally friendly.

Different types of hybrids work slightly differently from one another, but, basically, they are powered by both an electric battery and a gas-powered combustion engine. From about 0 to 25 miles per hour, the car runs on the electric battery. When you start to exceed 25 m.p.h., or you're operating under a heavier load, it will use a combination of the gas engine and the battery.

I did the research and discovered that hybrids cost about $3,000 to $5,000 more than their non-hybrid counterparts, depending on the model. Yet taking into account the tax incentives, better gas mileage, and overall goodwill of saving energy and lowering harmful emissions into the environment, my family settled on a hybrid Toyota Highlander.

While it is virtually impossible to precisely compare the costs of a model's hybrid and non-hybrid versions, here's a basic example. According to Cars.com, a 2007 hybrid, four-cylinder Honda Civic sedan costs $22,600. That is $4,840 more than the $17,760 for a regular Civic.

The hybrid averages 50 miles per gallon, while the non-hybrid averages 34. If you drive 15,000 miles in a year and pay $3 a gallon for gas, you will need to buy 300 gallons of gas for $900 for the hybrid, as opposed to 441 gallons for the non-hybrid for $1,324. Your savings will be $424 a year.

With just the fuel savings, it will take about 11 1/2years to make up the $4,840 additional cost for the car. Yet more is involved than just saving on gas.

This year, my family received a $2,600 one-time tax credit on our Highlander. Tax credits range from $250 to $4,000, depending on the model and year. (Check www.irs.gov to be sure.)