Green Energy from Osmosis

Energy crisis is a very complicated problem. It is an ongoing problem that is getting worse day by day. Lot of solutions and new technologies are designed to fight the problem of energy crisis. But it is remaining unsolved in spite of several efforts.

People realize the energy crisis only when their electricity bill gets dearer or cooking gas or petrol prices get costlier. The reason for energy crisis is that we lack proper understanding and insight of the complex causes and their solutions.

Some of the causes for energy crisis are: over consumption of fuels, poor infrastructure, improper utilization of renewable energy sources, wastage of energy, accidents and calamities, lack of sufficient rainfall or torrential rains, over population, poor distribution system, global warming, climate change and so on….

How to solve the energy crisis?

The problem of energy crisis cannot be solved in months or in days.  We have to work towards attaining self-sufficiency with respect to energy.  We have to use energy saving devices. We also have to use energy efficient devices. We have to reduce over dependence on non-renewable energy resources.  That means we should start depending on renewable energy resources for example, solar, wind, bio gas, geothermal energy resources because these energy sources are found in abundance in Nature and can be replenished.

The above mentioned renewable energy resources cannot be used  throughout the year because each one them have geographic and climatic limitations. Now we have to think of an energy resource that will provide us energy throughout the year nonstop and it should be environment friendly and user friendly. One such is the energy obtained from osmosis.

What is Osmotic Power?

Osmotic power is the energy derived from the difference in salinity between seawater and fresh water, which is harnessed to generate electricity.

An osmotic power generating station has a limited number of components: 

A semipermeable membrane contained in modules. Freshwater and seawater filters that optimize membrane performance. 

A turbine that generates a driving force based on the osmotic pressure and permeation flow rate.

A pressure exchanger that pressurizes the seawater feed required to maintain high salinity levels downstream from the membrane.

Principle: When fresh water is separated from seawater by a semipermeable membrane, the fresh water moves by osmosis through the membrane into the seawater. Salt ions travel through the membrane until the concentration of the two fluids reach equilibrium. Salt ions are electrically charged atoms.  The movement of these charged ions can be used to generate electricity. The resulting osmotic pressure, combined with the permeation flow rate, turns a hydraulic turbine, producing electricity.

Method: The osmotic power plant has two chambers separated by an artificial membrane to store fresh water and salt water. The plant uses hundreds of meters of pipes to channel salt water and fresh water into the power plant.  Osmotic Power Plants can be built where river meets sea. Seawater and freshwater are fed into separate pipes via filters which remove humus and other particles that can block the membranes. The water is then fed into the membrane system, which consists of spiral coils. The concentration of salt in the seawater should be sufficiently high to generate the required pressure. The freshwater is drawn through the membrane across to the saltwater. The increase in volume creates a pressure which forces the water through the turbine and generates electricity. 

Energy obtained from osmosis has the following advantages:

Osmotic Power is a clean energy resource.

Osmotic Power is a noise free and pollution free energy resource.

Osmotic Power is a spontaneous and natural process.

The energy obtained from osmosis is a renewable energy resource. So we can replenish the resource.

There is no risk of running out of salt as salt is not consumed during the power generation.

There is no impact on the environment.

When energy is being produced the amount of heat produced would heat up the environment by just ½ degree Celsius. Therefore this process does not harm the marine animals.

This energy is not so far exploited. If we start using this technology for the production of electricity, the scenario of the world will change.

https://www.youtube.com/watch?v=Oc5bXa5PcWo