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Category Archives: clean water









































Water makes up 71% of the planet earth and it is the most potential energy source of the future. Water is a product of combustion between Hydrogen and Oxygen, two most abundantly available elements and   vital for life on earth. The bondage between Hydrogen and Oxygen is so strong that it requires a certain amount of energy to separate them. Separation of Hydrogen and Oxygen using the process of Electrolysis is a well-known technology. Separation of water by high temperature using Thermolysis has also been studied.  In both the processes the separation of Hydrogen and Oxygen after decomposition is a key step because of the strong affinity between the two elements. Hydrogen has to be separated in a pure form without any trace of Oxygen. Currently most of Hydrogen is generated commercially by steam reforming natural gas because of its easy availability as piped gas in many developed countries. Moreover steam reforming is a well established commercial technology that has been used for decades in chemical process industries. The hydrogen resulting from steam reforming is acceptable for combusting in Hydrogen internal combustion engines but not pure enough for a Fuel cell car. Any trace of impurity from natural gas such as Sulfur or Mercaptans can potentially poison the catalyst used in fuel cell which is very expensive. Hydrogen with purity less than 99.99% is not recommended for Fuel cell applications.

Currently there are few issues to be addressed before Hydrogen becoming a commercial fuel. The energy required to separate Hydrogen from water by commercial electrolysis is about 6Kws (kilowatts) to generate 1 m3 (cubic meter) of Hydrogen. Two key factors for electrolysis are purity of water and  direct current source. Water of certain purity is a critical part for Hydrogen generation. Deionized water with electrical conductivity less than 0.10 micro Siemens/cm is required. Normal drinking water conductivity is less than 100micro Siemens/cm. The potable water can be deionized with reverse osmosis system to get necessary quality. In fact both high purity water and direct current are not commercially available. A renewable energy sources such as solar or wind that generates direct current can be used for electrolysis. This will drop batteries and rectifier that we normally use in renewable energy systems. The generated Hydrogen can be stored in cylinders under high pressure. The stored hydrogen is the stored energy that can be used as and when required.  We can use the stored Hydrogen to generate electricity to meet our power requirement whether it is a home or business or industry. The major advantage with this system is that we can generate power when we need and we don’t have to depend on the grid power. We can also export surplus power to the grid. In fact all DC appliances can be connected with DC power from Fuel cell and operated to improve the efficiency. Such a system is ideal for remote locations without any grid supply such as remote villages or islands.

The same stored Hydrogen can also be used as fuel for a car whether it is a combustion engine or a Fuel cell car. Hydrogen can be compressed and stored under high pressure. Alternatively, Hydrogen can be stored using metal hydrides in smaller volumes. Honda introduced the first fuel cell car in the market in 1999. Since then they have made considerable improvements. Honda FCX Clarity, sedan offers a mileage of 270 miles for a single cylinder of Hydrogen at 5000 psi pressure. They are introducing a latest model with Hydrogen pressure at 10,000 psi which will considerably improve the mileage further. Unlike Hybrid cars, Fuel cell cars run silently and experts who have test-driven the car are very much impressed with the performance. Similarly Ford introduced Hydrogen combustion engine 6.8 liters V-10 engine to power E-450 Hydrogen shuttle bus. Ford modified their Gasoline engine to suit Hydrogen fuel.

Substituting Gasoline with Hydrogen is no longer a theory but a commercial reality. More and more research is being undertaken to improve the performance. Currently the cost of Hydrogen cars and Hydrogen fuel is expensive, due to lack of infrastructures to manufacture such cars or to distribute Hydrogen. However these cars will soon replace gasoline cars. Similarly homes and business can generate their own electricity for their daily use using stored Hydrogen. Water will become the fuel of the future and Hydrogen will clean up the air that has been heavily polluted by fossil fuels for decades.

Renewable energy is one of the fastest growing energy sources of our times. But still there are many obstacles to overcome, before it can substitute current methods of electricity generation using fossil fuels, or substitute petrol in cars. The main obstacle is, the intermittent and unpredictable nature of renewable energy sources, such as wind and solar. Wind blows only certain seasons of the year and then wind velocity fluctuates widely in a day. Similarly sun shines only certain hours in a day and the intensity of radiation varies widely in a day. The wind velocity and sun’s radiation intensity are critical components in designing a reliable energy system. It is an anomalous situation, when we need power, there is no sun or wind; when sun shines or wind blows, we may not need any power. How to overcome this anomaly? That is the key, in successfully deploying renewable energy technologies.

Currently we are using batteries to store the energy. When there is a wind with reasonable velocity or sunshine with reasonable radiation intensity, we can generate power and store them in batteries. The wind velocity should be above certain threshold limit, say such as, a least wind velocity of 3mts/sec for amount of hours, while designing a wind based energy system. The same principle applies to solar energy and we need certain minimum solar   intensity and several hours. But in reality, we don’t get these minimum operating parameters, which make the design of a renewable system more complicated.

Batteries can accumulate these small energy generations by intermittent sources of wind and sun, and store them. But these batteries have certain life between 3-5 years and requires regular maintenance, replacements.They also have certain charging and discharging cycles and limitations. At the end of its life, it has to be disposed carefully because these batteries are made of lead and acid, which are toxic materials. Many companies are trying to introduce better technologies such as ‘flow batteries’. But experience shows that such batteries are confined to only smaller capacities. Large scale storage is expensive and sometimes it is not economically feasible. Lithium-ion batteries are more efficient than Lead-acid batteries, but they are more expensive so the renewable energy projects become expensive and cannot compete with conventional fossil fuels, in spite of higher tariffs offered by Government as incentives. Moreover the demand for Lithium-ion batteries will increase substantially in the future, as more and more Electric cars are produced. But lithium sources are limited and it is not sustainable.

The best option to develop renewable energy systems is to generate Hydrogen using renewable energy and store them, instead of storing them in batteries. We can use stored Hydrogen to generate power, or use as fuel for the car, as and when we need. There are no maintenance or disposal problems with Hydrogen storage, when comparing with batteries. Hydrogen generators (electrolyzers) can generate Hydrogen when the intermittent power flows from wind or sun. They can run from a range of capacities from 5 to 100% of rated capacity and they are more suitable for renewable energy sources. But there will be a loss of energy, because the amount of power required to generate Hydrogen, is more than the power generated from the resulting Hydrogen by a Fuelcell.The initial cost will be higher, but it will give operational flexibility with least maintenance, and even adoptable to remote sites. Technology is improving to cut the cost of fuel cells and electrolyzers so that Hydrogen based renewable energy will become a sustainable source of energy in the future. Hydrogen is the only solution that can solve both power generation and transportation problems the world is currently facing.

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