Alternative Renewable Energy

Since the industrial revolution humanity has been relying mainly on fossil fuels as a source of energy, both for electricity and fuel. But during the 20th century we realized that this type of energy generation is harmful to the environment because of the greenhouse gases fossil fuels release into the atmosphere and which cause climate change. For that reason, and the fact that we are going to run out of fossil fuels, we have to switch to alternative renewable energy. This term refers to energy types that are clean and can renew themselves in a perpetual cycle. Solar, wind, tidal, wave, hydroelectric, biomass and geothermal are some examples of alternative renewable energy resources.

These types of energy sources are not exactly new and have been known to humanity since the dawn of civilization. The challenge we face now is to scale them up to feed the gigantic energy demands of our industrialized societies. In order to achieve that, there is a great deal of research going on, both on the public and private sectors. There is a consensus that no single type of energy will provide a silver bullet solution to the energy crisis we need to overcome but a mix of solutions of decentralized energy generation is more likely to be what the future has in stock.

Solar is by definition the most renewable source of power but harnessing and distributing solar power in an economically viable and efficient way is still a tech dream. Solar power can be used in two ways: to heat water through collector panels (thermal solar) and to generate electricity, which is what photovoltaic solar energy does. Currently solar PV panels reach a rate of efficiency of around 20%, which refers to the percentage of sunlight that actually becomes electricity. Increasing this rate is one of the main focuses of solar power researchers. Wind power is also a very popular alternative form of renewable energy and in some countries such as Denmark and England it has become quite a force to be reckoned with. Wind power is generated with massive wind turbines featuring three blades of 30 meters in length. Small, vertical axis wind turbines for domestic use are also getting more efficient and should increase in popularity in the near future. As far as large wind farms go, one of the main trends in this industry is to install them offshore.

In terms of alternative renewable fuel, biofuels emerged as the most popular and supported solution. Ethanol is the most common type of biofuel and is widely used in Brazil and the U.S. The problem with biofuels is that they can compete with food crops and drive deforestation, which cancels out any environmental benefits it offers over fossil fuels. One cleaner solution currently being developed is cellulosic ethanol, which is made from non-food crops, grasses, wood, sugarcane bagasse and other types of more sustainable raw materials.