Use Renewable Energy
There are many ways to conserve the use of fossil fuel; using the sun, wind, or water to produce electricity are among them. If you choose to do this, you will be forced to be careful in the way you use your electricity because it is limited. Whether you get your electricity from alternative sources or from the grid, it pays to choose energy efficient appliances. Front-loading clothes washers, for instance, use much less electricity, water and soap than the top-loaders. LED lights use much less electricity than standard bulbs or even compact flourescents. Many appliances use electricity by just being plugged in (known as phantom loads); be sure to avoid this.
Besides conserving electricity, energy can be saved by using solar to heat water and your home. Good home design will allow daylight to provide lighting when possible. Under some circumstances wood heat is a renewable energy resource, along with geothermal. Even methane can be produced from biomass, collected and used for heating and cooking. Any strategy that helps conserve the use of fossil fuels for any of these applications is worth considering.