All Energy from the Sun
Essentially all energy on the Earth can ultimately be traced to the sun. Our whole biosphere has evolved as an ultra-efficient means to transform solar rays into chemical energy required for life. In our quest for renewable energy, we would be well served to mimic natural ecosystems. Solar arrays coupled with fuel cells for energy storage may be the holy grail upon which advanced human societies depend. Humanity would be well served to invest mightily in their continued development. The price of a watt of solar energy has fallen from $100 to $8 in the past three decades. It is time to get serious about solar energy as a means of averting environmental collapse.
It's Getting Cheaper to Tap the Sun
…providing homes with electricity and heat from the sun is getting more buzz than it has in decades. In the 70's it seemed that buyers of solar systems were mostly isolated tree huggers who somehow had a small fortune to spend on panels, but now urban and suburban homeowners are looking to the sun hitting their roofs for relief from rising electricity and heating costs. Higher utility bills, though, are just the stick. The carrot is the falling cost of solar systems that are lighter and more efficient and feature new designs, like solar panels that double as window awnings. Standardized installations and economies of scale for equipment production have helped drive costs lower.