locomotion of an earthworm

A tighter built home means less outside air infiltrating in the home, which means less oxygen to use for combustion within the furnace. As the furnace burns fuel and oxygen for combustion, it "eats up" surrounding air, which has to be "made up" with fresh air. If air cannot type in the home as easily anymore, this can cause serious issues. As the surrounding air is utilized for combustion, rather than substituted with oxygen, a negative pressure inside the space can happen. This could create combustion problems for the furnace, plus burn up fresh air for anybody inside the home. The practical options for energy range from the standard fuels, natural gas, petroleum (or oil), and coal. Fossil fuels are referred to as nonrenewable energy sources because, once used, they are gone. Scientists are exploring the practicality of other sources called renewable energizes. These include sun, wind, geothermal, water, and biomass. The renewable power resources are very important in long range energy planning simply because they will not be depleted.