Central heating differs from space heating in that the heat generation occurs in one place, such as a furnace room in a house or a mechanical room in a large building (though not necessarily at the "central" geometric point). The heat is distributed throughout the building, typically by forced-air through ductwork,
Plumbing follows the basic laws of nature -- gravity, pressure, water seeking its own level. Knowing this, you can understand its "mysteries" and make dozens of fixes to your home's plumbing system. You can save yourself time, trouble, and money!
Natural gas is a fossil fuel formed when layers of buried plants, gases, and animals are exposed to intense heat and pressure over thousands of years.
The energy that the plants originally obtained from the sun is stored in the form of chemical bonds in natural gas.
Solar energy is radiant light and heat from the sun harnessed using a range of ever-evolving technologies such as solar heating, solar photovoltaics, solar thermal electricity, solar architecture and artificial photosynthesis.
Solar technologies are broadly characterized as either passive solar or active solar depending on the way they capture, convert and distribute solar energy. Active solar techniques include the use of photovoltaic panels and solar thermal collectors to harness the energy.
Passive solar techniques include orienting a building to the Sun