If you are planning on completely cutting yourself off from the grid, then you need to consider what that really means.
Living off the grid means:
Disconnecting from the electric and communication grid.
Having a way to get water that does not rely on the municipal water supply.
Having to deal with your own waste and sewage.
Being able to heat and cool your home without being hooked into natural gas lines.
Dealing with local zoning laws and legal issues.
You also need to understand that this is a huge lifestyle change.
Let's face it; most people are not ready to live off the grid. The average American household uses over 8,900 kilowatt-hours of electricity and somewhere around 144,000 gallons of water each and every year. If you're planning on living the same lifestyle that you're currently living, you're probably not ready to go off the grid – unless you have an unlimited amount of money to spend on completely retrofitting or replacing everything in your home with off-grid alternatives.