It started out as a sort of experiment on two wheels. Now, six years and two kids later, we’re still primarily a human-powered family with no approaching vehicle in sight. As a result, not only has the quality of our lives been vastly improved, but we’ve realized that we’re doing our children and our community an immeasurable service every day.

Considering the amount of energy required to propel humans from point A to point B by car, especially at a rate of one per person, they are probably the most inefficient means of transportation civilization has yet devised. Though we account for less than 5 percent of the world's population, Americans consume a quarter of the world's oil -- half of which is burned by internal combustion engines. When looked at through the smoggy haze of a rush-hour traffic jam, it seems that automobiles do more damage to the planet than the rest of industrial society combined.

On the flip side, bikes are one of the most energy-efficient transportation machines ever created. Propelling yourself across town every day not only drastically improves your fitness level, but also offers children and parents alike a connection with the environment that is unattainable using four-wheeled modes of transportation.

Two-Wheeled Economics
The average American spends more than $500 a month on a car, so it seems to be an economic no-brainer to forego one unless it’s absolutely necessary.

One thing people often forget when weighing their transportation options is that a few months of car payments can buy your family a veritable arsenal of hi-tech transportation gear. State-of-the-art bikes, skates, wagons, baby joggers and skis fill our garage at a fraction of the cost of a new SUV, and provide us with an endless source of fun and adventure. When our kids cruise down the street in their bike trailer, they do it in style, generating stares of envy from every car-seat-incarcerated kid in town.

Ironically, many drivers see their automobile as a necessary component to their freedom, when in reality they spend much of their lives in bondage to it. Working to afford a car so they can drive to work, pouring every available cent into keeping it running and insured, dreading the inevitable moment when it makes contact with another vehicle or leaves them stranded on the side of the road at the mercy of the nearest mechanic.

Location Matters
Of course, if you decide to go auto-free -- especially with kids -- one of the first things to consider is where to live. Obviously, cities like Los Angeles -- the freeway-feuding car-driving capital of the world -- and any place that experiences extreme weather, like Montana, are off the list.

My wife and I chose Portland, Oregon to begin our car-free odyssey because it has relatively mild weather, an extensive mass transit system and a maze of bike lanes. When my wife’s mother found out we were pregnant with our first child she said, "So, now are you going to get a car?"

"No," we replied, much to her dismay. Instead, we opted to get a bike trailer and move to a smaller community where everything essential for modern living is within walking distance. It’s easy to forget that this is how a majority of the planet’s population lives.

Not Owning A Car Doesn’t Mean Not Driving One
Usually the first response people have when they find out that we’re auto-free is: "What do you do when you want to leave town?"

We respond much the same way my friend Teresa does when people ask why she doesn’t wear a watch: "Why should I wear a watch when everyone else knows what time it is?"

The point is that there are more than enough cars to go around. In fact, in 1998 there were 25 million more vehicles in the United States than there were licensed drivers. Most of our friends have cars they are willing to share for the occasional airport run or shopping trip, and on the random occasion when we want to leave town, we (gasp!) rent a car.

The math involved with renting a car one weekend every month still works out better than if we owned one. It’s also brand new, fully insured, and on the off chance it breaks down or we have to leave its smoking hull in a ditch somewhere, all we have to do is call the rental agency and ask for a replacement. It’s not our car, and hence, not our problem.

In the end, that’s probably what keeps us on our bikes. Life is just more simple without a car and it makes little sense to spend thousands of dollars inflicting a tremendous amount of damage on the environment just so we can motor to Starbucks and back in a machine capable of being a lunar rover. Especially when doing the same trip by bike is likely to put a relaxed smile on our faces and make the kids to scream "Wheee!"