Skip navigation

Category Archives: Fuelcell

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.

I use the word ‘renewable Hydrogen’ for the Hydrogen derived from water using  renewable energy sources such as solar, wind, geothermal, wave energy, ocean thermal energy conversion systems and biological processes. Hydrogen is clearly the energy source of the future because it has got the highest energy content, compared to any other fossil fuels such a diesel, gasoline, or Butane. The energy content is more than three times that of natural gas, which is considered as the cleanest commercial fuel available in the market. The heating value of Hydrogen is 61,100Btu/lb compared to 23,879 Btu/lb of natural gas. Moreover, only Hydrogen can guarantee a complete reduction of Carbon dioxide from the atmosphere. The problem with renewable Hydrogen is the cost, at current situation. The DOE (department of energy, USA) has targeted a cost for Hydrogen production at $10to $15 per mmBtu, which is comparable with current Natural gas cost. Currently bulk of the Hydrogen is commercially produced by steam reforming natural gas. However; this process will emit carbon dioxide at the rate of 11,888gms per Kg of Hydrogen produced. Though the cost of Hydrogen by this route is cheaper, mitigation of carbon dioxide is clearly an environmental issue. However it is an important route during the transition process from fossil fuel to a full fledged Hydrogen economy of the future.

Natural gas is increasingly in demand and the price of natural gas keeps increasing as the supply demand gap widens. Large natural gas liquefaction plants are already in operation in many parts of the world and number of new plants are under implementation or under planning stages. Japan, South Korea, Taiwan are three largest importers of LNG (liquefied natural gas) from Australia in Pacific region. There are many coal seam methane gas facilities already in operation in Australia and many are under planning. Due to the disaster at Fukushima nuclear plant, Japan has stepped up its import of LNG. India and China, which have been traditionally using coal as a major fuel, have started importing LNG for their power plants. This has pushed the prices of LNG in the international market significantly. Though LNG is relatively a cleaner fuel, it is very expensive to build import terminals. Moreover countries like India and China do not have a good distribution network by peipelines.The economy of scale also favor only large capacity LNG plants and terminals.  However it is not a sustainable solution in the long run considering the fact that supply of natural gas also keeps dwindling steadily. Despite all these obstacles, Governments around the world are looking only for short-term solutions like LNG, simply because it is an easy fix.

Biogas can be generated from organic waste and waste waters by anaerobic digestion. Many sewage treatment plants around the world have started generating biogas to generate power for captive use and to export the surplus power to the grid. Similarly municipalities are also implementing projects to convert ‘waste garbage’ to ‘energy’. However, the scale of operation favors only large capacity plants in larger cities. However these biogas plants will still emit carbon dioxide because biogas will be combusted using conventional engines, micro turbines and Fuelcells.This is once again a temporary solution only. We need to look beyond all these technologies to really cut the greenhouse emissions.

The only option is by Renewable Hydrogen and we need to take steps to make it a commercial reality. Biohydrogen is another potential technology. However the technology is still in a nascent stage but it is promising. Renewable Hydrogen using renewable energy sources are our best bet. Countries have already started investing in renewable energy infrastructures such as solar and wind. They can as well plan for renewable Hydrogen so that they can be certain about three things. One, they can generate and use uninterrupted power supply without importing oil or gas. Secondly they can be certain that greenhouse emissions can be reduced to pre-industrialization level. Thirdly they can be certain about the last cost of energy and its stability in the long run. These are three important factors every citizen of a country is looking for. It requires political will, determination and swift action on the part of each Government.

Is this your new site? Log in to activate admin features and dismiss this message
Log In