Basically a suburban neighbourhood today has a grid that fuels the neighbourhood. You don't see the spaghetti piping of natural gas. Propane would be the same thing. The fuel tank would be off-site somewhere else. You wouldn't see it. There could be a network right under the homes to fuel everything that you want done in your house, including your hot water tank, furnace, fireplace, stove, dryer—even your lights.
On March 6th, 2012. See this statement in context.