Metateps

There is no grid available. This may be by choice or by fate. Many people in Third World countries and even in rural America do not have access to all the traditional grid utilities. It may be that you're rich and have found your dream property but it's too far out in the boondocks to tie into the grid. Or perhaps you're dirt poor and you're off-grid because you live in the squalor of a grid-less mud village high in the Andes. You might live in a religious community that shuns modern conveniences. For whatever reason, the traditional grid is absent.

To minimize the environmental impact of the grid. To reduce your "carbon footprint" and allow the Earth to recover from everything we've done to it.

To avoid the high cost of traditional utility connections. This reasoning belongs largely to the wealthy who have multiple properties that are only intermittently in use.

To save money by lowering utility bills. This is a pipe dream under the current circumstances. You have to spend money to save money, and becoming self-sufficient costs a lot of money. For a huge investment you might make utility bills disappear, but you will still have monthly costs (battery replacement, etc.).

To ensure you have services when the grid goes down. This is probably the best and most rational reason for minimizing your reliance on the grid. You may be a survivalist, or just average parents making sensible arrangements to take care of your family in a disaster.

To entertain an intelligent mind. If you like to tinker with mechanical and electronic gadgets, and you actually like physics and chemistry and electronics, this is definitely the life for you.

To reduce our national dependence on fossil fuels, especially oil. In 2007 and 2008 we all watched in disgust as oil prices dragged us into economic purgatory. Meanwhile, our kids were still getting shot and blown up on the streets of Baghdad in a "war on terror" that is more about oil than terrorism. Perhaps there's no revenge like economic revenge. We should work hard to be in a position to boycott oil from antagonist states instead of invading them.

Public image. This is the worst reason for going off-grid. Being able to go green implies many things, among them wealth and political influence. It's like a mob boss going to church on Sunday.