The depletion of the earth's finite resources is not sustainable, either environmentally or economically. Human activities are contributing to global warming. We can neither predict nor control the effects, such as changing weather patterns. We are playing with fire. The rapidly increasing industrialisation in developing countries does not have to repeat the energy use patterns of the industrial revolution.
Technology offers practical alternatives.
Further improvements in technology, combined with the economies of scale, make renewable energy both practical and cost competitive in many applications already and in most applications in the near future. Economically, the advances that have been made in renewable energy technologies in the last two decades, including higher efficiencies, improved quality and increased reliability, have made applications of renewable energy more attractive. The cost of renewable energy technologies will drop once the benefits of renewable energy, including its sustainable nature and the minimal pollution it creates, are recognized by a larger percentage of the population. The use of renewable energy is as old as the harnessing of fire and the discovery of the comforts of the south-facing cave. Until the mid-1800s, most of our energy came from burning wood and peat.