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Electrolysis of Water -Make Hydrogen from Water – and Hydrogen Cars

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Electrolysis of Water

Electrolysis is the process of passing direct electric current through molten ionic compound to decompose it into its elements. When direct electric current is passed through water, water will dissociate into its elements of hydrogen and oxygen gas.

The formula for water is 2H2O (liquid) → 2H2 (gas) + O2 (gas)

When direct electric current is connected to two electrodes made of inert metals and the two electrodes are placed in water, hydrogen gas will be produced on the electrode placed to the +ve and oxygen will be produced to the electrode connected to the –ve. The positively charged electrode is called the cathode and the negatively charged electrode is called the anode. From the formula above, we can see that the volume of hydrogen produced will be twice the volume of oxygen produced.


An electrolyte is a solution containing free ions that makes it electrically conductive. If common salt is dissolved in water, the strong solution will conduct electricity. A nearly saturated solution of salt and water is called brine like in sea water. Brine is one of the electrolytes that may be used in the Hofmann voltameter for production of hydrogen and oxygen. Hofmann voltameter is normally what students use in school laboratories for production of hydrogen and oxygen science projects.

Hofmann Voltameter

A Hofmann voltameter has three joined upright cylinders as shown in the picture below. The middle cylinder is open at the top to allow the addition of electrolyte solution. At the bottom of each of the two outer cylinders is a platinum electrode. One electrode is connected to the positive terminal of a battery and the other electrode is connected to the negative terminal of a battery. When electrical current run through the Hofmann voltameter, gaseous hydrogen forms at the cathode and gaseous oxygen forms at the anode. Each gas displaces water and collects at the top of the corresponding tubes, where it can be drawn off for appropriate use.

Hofmann voltameter for production of hydrogen and oxygen in laboratories.

Hofmann voltameter for production of hydrogen and oxygen in laboratories.

Gibbs' Free Energy

In theory, the amount of electrical energy used equals the change in Gibbs free energy of the reaction plus the heat losses in the system. The electrical energy in the battery has been converted to another form - hydrogen fuel.

Hydrogen - an Energy Carrier

Hydrogen is an energy carrier. When hydrogen burns in air, it produces a frame which is heat and water. Water is not a pollutant and therefore we say hydrogen is clean fuel unlike the natural fuels we use in our cars today that produces carbon dioxide and greenhouse gases.

Fossil Fuel Inputs

Yes, the beauty of using hydrogen as an energy/fuel is that hydrogen can be prepared without using fossil fuel inputs and as such vehicle propelled using hydrogen would not contribute to carbon dioxide emissions. But we need to use electricity to produce hydrogen as already shown. How can we produce electricity without using fossil fuel inputs? Perhaps we can use hydroelectricity or solar energy.

Solar Electricity

We can use solar electricity to store the energy in a battery and then use the battery to generate hydrogen. This way, we would have clean hydrogen to power our cars without generating any greenhouse gases from the process. This is what the caring Mother Nature wants us to do in the very near future, otherwise we may all perish.

Best Things in the World Are Free

In summary, we can say we need the following to produce clean hydrogen fuel:

  1. Water
  2. Salt, or seawater
  3. Sun energy

The best things in the world are free. These three things (salt, water and solar energy) are provided in abundant and free (abundant and free in Atlantic Ocean, Arctic Ocean, Indian Ocean, Pacific Ocean, and Southern Ocean) by God/Mother Nature and if man was fair to himself, he need not spend even a cent to obtain any of the three products.

Rooftop Photovoltaic Panels

Today, the population of the earth is approaching 7 billion people and each an every person lives under a roof. A house can be roofed 100 percent using solar panels.

A house can have 50 rooftop photovoltaic panels that convert sun energy into electricity. Each solar module can produce 110 for a total of 5.5 kilowatts. Get 8 hours of sunshine per day as it happens in regions around the equator and you have yourself 44 kilowatts of electricity per day. That’s what you get in 50 solar panels covering a roof measuring about 8 metres by 6 metres – the average house for the common man may just measure about that. This solar energy just need to be converted from direct current (DC) to alternating current (AC) which is then plugged into the national grid for distribution to users all over the country. In return, your electrical utility meter is driven backward with the equivalent of what you have produced. You can as well be paid for producing clean electricity by the electricity distributing company. The electricity you have produced can then be sold to companies producing clean hydrogen fuel using electrolysis. If you and I did the same, and everyone else, the world would produce enough solar electricity which can be used to produce clean hydrogen fuel for powering our cars. And in return we all shall benefit by having an atmosphere free of greenhouse gases.

By plugging the solar electricity you have produced into the national grid, you eliminate the need to have batteries for storage. By not using storage batteries, you avoid polluting the environment from disposal of used old batteries.

Governments to Provide Funding

Roofing a house with 50 solar panels is not a cheap investment for everyone. Governments throughout the world need to intervene and provide the necessary funding to its citizens.  The role of you as a citizen would be to ask your government through your representative in legislative assembly to provide a mechanism for such funding. You need do that because you will benefit as follows:

  1. you will make some money (or being credited in your bill) for selling clean solar energy to your electricity distributing company
  2. You will have a clean environment free of greenhouse gases
  3. Your country will not need depend on other countries for oil imports to power your car.

Internal Combustion Engines

Hydrogen can be used just like traditional gasoline for powering engines and all you need do is a slight modification to the internal combustion engines we already have in our cars - hydrogen engines burn fuel in the same way that gasoline engines do. The major drawback in hydrogen as a fuel is that hydrogen has low energy content per unit volume compared to the gasoline we already use. This means we will need large tankage weights in our cars, and because of this the investment in infrastructure for distribution of hydrogen will not be cheap.

Honda FCX Clarity. Hydrogen can be used just like traditional gasoline for powering engines.

Honda FCX Clarity. Hydrogen can be used just like traditional gasoline for powering engines.

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Hybrid Electric Cars

Alternatively, rather than store energy in hydrogen, we can as well use plug-in hybrid electric cars which are hybrid cars that can be plugged into the electric grid of whose electricity have been obtain from clean solar energy.

First Law of Thermodynamics

The first law of thermodynamics state that energy can neither be created nor destroyed but can only change from one form to another. By doing electrolysis of water to make hydrogen, we are not trying to make energy but rather to store electrical energy from electricity/sun into hydrogen which in return is used to power our cars.

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tianode on February 16, 2012:

I'm quite into the idea of engineering equipments being beautiful.

azmol on August 31, 2011:

i want to business with you. now what can i do?

stereoscar on March 12, 2011:

Wow, it was interesting.

Emma from Houston TX on March 09, 2011:

Good theory that is well arranged for a greater understanding,thanks for sharing.

Joe on March 02, 2011:

I enjoy reading your hub, i believe in future we will be using renewable energy which is much lesser in cost and eco friendly :)

Hello, hello, from London, UK on January 30, 2011:

A very interesting and fascinating invention. Thank you for your great informative hub.

Neil Sperling from Port Dover Ontario Canada on January 29, 2011:

Good theory - the batteries and solar panels are made from materials manufactured out of oil by products (Plastics) and minerals such as copper mined from the planet. The cost to produce the power you are talking about is enormous with today's technology. Until such time power produced by solar is less than current methods using nuclear, coal or gas burning turbines your idea would break the bank.

Also - water being a precious resource and not in abundant supply everywhere, another problem with your idea arises.

Then there is the extra land fill waste that will come from old batteries, broken solar panels and the like.

Maybe we should go back to horse and buggy!

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