Some Surprising Sources Of Alternative Energy

 
You've heard of wind and solar power, biofuels, hydroelectric, tidal and wave power, but clean, green energy is all around us in the natural world, and scientists have only begun to answer the question of how to tap it.

 

Here's a list of 10 practical sources of alternative energy - some of them you've probably never heard of.

1. Saltwater power - It has been called saltwater power, osmotic power or blue energy, and it is one of the most promising new sources of renewable power not yet fully tapped. Just as it takes huge amounts of energy to desalinate water, energy is generated when the reverse happens and saltwater is added to freshwater. Through a process called reverse electrodialysis, blue energy power plants could capture this energy as it is released naturally in estuaries around the world.
2. Helioculture - The revolutionary process called helioculture was pioneered by Joule Biotechnologies it generates hydrocarbon-based fuel by combining brackish water, nutrients, photosynthetic organisms, carbon dioxide and sunlight. Helioculture produces fuel directly — in the form of ethanol or hydrocarbons and does not need to be refined. The method essentially utilizes the natural process of photosynthesis to produce a ready-to-use fuel.
3. Piezoelectricity - As the world's human population approaches 7 billion, tapping into the kinetic energy of human movement could become a source of real power. Piezoelectricity is the ability of some materials to generate an electric field in response to applied mechanical stress. By placing tiles made of piezoelectric material along busy walking paths or even in the soles of our shoes, electricity could be generated with every step we take — making people into walking power plants.
4. Ocean Thermal Energy Conversion (OTEC) - Ocean thermal energy conversion is a hydro energy conversion system that uses the temperature difference between deep and shallow waters to power a heat engine. This energy could be tapped by building platforms or barges out at sea, taking advantage of thermal layers found between the ocean depths.
5. Human sewage - Even human sewage can be used to create electricity or fuel. Plans are already underway to power public buses in Oslo, Norway, with human sewage. Electricity can also be generated from sewage using microbial fuel cells, which utilize a bio-electrochemical system that drives a current by mimicking bacterial interactions found in nature.
6. Geothermal power - Geothermal power works by pumping cold saltwater down to rock which has been heated by conduction from the Earth’s mantle and by the decay of radioactive elements in the crust. As that water heats up, the energy created can be converted into electricity by a steam turbine. The advantages of hot rock power are that the output can be easily controlled and it can provide energy 24/7.
7. Evaporative energy - Scientists have invented a synthetic, micro-fabricated "leaf" that can scavenge electrical power from evaporating water. Air bubbles can be pumped into the "leaves", generating electricity generated by the difference in electrical properties between water and air.
8. Vortex-induced vibrations - This form of renewable energy draws power from slow water currents and was inspired by the movement of fish. The energy can be captured as water flows past a network of rods. Eddies, or swirls, form in an alternating pattern, pushing and pulling an object up or down or side to side to create mechanical energy. It works in the same way that fish curve their bodies to glide between the vortices shed by the bodies of the fish in front of them.
9. Helium 3 - Helium-3 is a light, nonradioactive isotope that has immense potential to generate relatively clean energy through nuclear fusion. The only catch: it is rare on Earth but abundant on the moon. Many projects are underway to mine the moon for this resource. For instance, the Russian space company RKK Energiya announced that it considers lunar helium-3 a potential economic resource to be mined by 2020.
10. Space-based solar power - The sun's energy is unaffected by the 24-hour cycle of night and day, weather, seasons, or the filtering effect of Earth's atmospheric gases and proposals are underway to put solar panels in orbit and beam the energy down for use on Earth. The technological breakthrough here involves wireless power transmission, which could be performed using microwave beams.