The other day I was thinking about public transit, biking, and location and it dawned on me that just about any place in America can be easily accessible by bike and/or public transit so long as you can cherry pick your starting point. The biggest excuse I hear from people defending their lack of environmentally friendly transportation choices is that their hands are tied because of the inconvenient location of their home. The answer I generally give is that if you truly care about improving your personal energy efficiency then you need to be committed enough to move to the right location.
However, now I'm starting to wonder, do you really need to be committed? What if moving your home was easy enough that it didn't require any commitment? What about mobile homes? Surely it makes more sense to drive 10 or 20 miles once a month to be within comfortable biking distance of your job than to commute by auto 20 or 30 miles every day. Found a better place to get groceries on the other side of the county? No problem, simply "move" halfway between it and your job.
Sure, you'll need to use some energy to accomplish the move, but how much energy would you waste moving the contents of a conventional home. Moreover, how much energy would you waste by living in a conventional home and not moving to optimize your energy usage? For example, how much energy do you waste by not being located in a sunny location in the winter and a shady location in the summer? How much energy do you waste by not living within biking distance of a local farmer during harvest season or a good high school for the years when your child is of age?
Merchants, employers, and society in general change over time. What is optimal today may not be optimal tomorrow and although a small home in a densely populated area might theoretically be the most efficient living arrangement, it might not be adaptable enough to maintain that efficiency in the face of changing circumstances. Advances in energy efficiency go unimplemented in densely populated areas like NYC where soaring real estate prices ensure that decrepit 150 year old buildings remain inefficient and unrenovated. Moreover, societal habits and government spending are both biased against living in densely populated areas. Government subsidy of the roads makes it easy for people to run away from community issues instead of confronting them, contributing to blight and urban decay in otherwise ideal densely populated areas; Public transit and bicycle facilities are neglected in lieu of roads. So why not use the roads to our advantage? Why limit yourself to a small conveniently located apartment in the city when you can have a small conveniently located mobile apartment anywhere?
Granted, in terms of basic utilities mobile homes probably aren't particularly efficient, but with a little technology that might be fixable. There may also be legal issues with parking in one place for too long. Does anyone have information on these things? Is anyone aware of any studies which have considered the energy efficiency of such a mode of living?
I know there is a community of RVers out there, but my impression has always been that these are mostly retired folks looking to spend all their time traveling. To me the most striking advantage of this mode of living is for people that have a responsibility to be somewhere like a job or a school.