Central Indoor Gas Heaters
Gas is the most common heating fuel for central-heating gas systems, and for good reason! It is efficient (modern gas heaters approach 100% efficiency!), economical, and effective.
Central air heating systems differ from ‘local’ indoor space heaters in that instead of the heat being generated in the place it is desired, it is generated in one central location within the building. In your home, this is generally going to be the furnace in your basement. Air heated in the furnace is then blown through a series of ducts to all of the rooms in the house to be heated. In the simplest case this results in all rooms in your home being delivered the same amount of heat, though in more complicated (and expensive) systems the home can be divided into zones and the amount of heat delivered to each zone can be independently controlled.
Though central gas furnaces can be incredibly efficient in their own right, sometimes this isn’t the most efficent heating method available. For example, if you’re entire family is in the den watching movies for the whole night, it might make a lot more sense to use space heater rather than “efficiently” heat your whole home.
That said, though, central heating is often the way to go since you will have different people throughout the house and keeping the entire living space at a more constant temperature is easier as well as more comfortable. With central heat you don’t need to worry about putting on extra clothing when you leave the warm comfortable room or dragging that space heater into the next room with you.
Obviously, though, the infrastructure required for central heating is quite signficant and most homes will have it installed at the time of construction, though certainly if the duct work exists adding a furnace to your home is something that any heating contractor would be able to handle.
If you already have a gas furnace and find that your heating bills are expensive you should consider upgrading to a more efficient model. Newer furances can provide a lot more heat while burning a lot less fuel. Tax credits are available to soften the immediate blow of the new purchase and in the long run you can definitely see huge savings. Not to mention you get the fuzzy feeling of knowing you are contributing to less global warming.