Hydrogen is combustible and offers a high energy content. The only emission is vapor.
Hydrogen is not a primary energy source, but it is an excellent form of stable long term energy storage, superior to present batteries and easy to upscale.
Industrial scale hydrogen is primarily produced from natural gas or biomass, but electrolysis of water has been known since the first half of the 19th century.
Production of green hydrogen by solar and wind energy:
A modern and environmentally friendly way of producing hydrogen for energy use is electrolysis using renewable electricity from wind and solar power.
This is an increasingly more common type of hydrogen production, easy to upscale when needed. In the electrolyzer an electrical current is led through the water (DC). Hydrogen is collected at the cathode and oxygen at the anode. The process generates heat, which can be utilized in a heat exchanger or directly for heating or cooling of premises.
Theoretically 35,8 kWh is required to generate 1 kg of hydrogen
Practically around 50 kWh per 1 kg of hydrogen
The only exhaust emission is pure vapor
image text: Heat applications
image text: Electrical applications
The Fuel Cell
The fuel cell is already an old invention, older than the combustion engine and almost of the same age as the steam engine. Already in 1839, the Englishman William Robert Grove designed a fuel cell generating electricity. At the shift into the 20th century the theoretical principles for the modern fuel cell were known. In the competition race between the combustion engine, the electrical battery car and the fuel cell car the first option was the winning concept. The reason was easy distribution of the energy source in an independent transportation system.
Development of fuel cells was slowed down during the golden age of the petrol cars. In the last ten years membranes and other components have been developed rapidly and the lifespan of the fuel cells has increased at least ten times. You can use many other fuels, for example lignin from wooden pulp.
In the fuel cell energy is transformed from hydrogen to electricity and vapor. Each cell generates around 0,7 V. To reach higher voltage many cells are combined to a stack. Excess heat can be used in a heat exchanger system to generate hot tap water or cool air. The only emission is pure water.
There are six common types of fuel cells available, starting from alkaline fuel cells in submarines and rockets to modern PEM polymembrane fuel cells and alkaline and efficient AEM fuel cells and solid-state oxide fuel cells. The smallest fuel cell weighs only 30 grams. The lifespan of a PEM fuel cell is estimated to 90 000 hours.
For propulsion of vessels and as powertrains for land vehicles one or several electric motors are used. They are fed with power from the fuel cell. A battery supplies the power during a few minutes at start while the fuel cell is heating up.
Hydrogen is a gas that exists in our natural environment. We breathe hydrogen in very small concentrations every day. A possible leakage from a tube or a fuel cell is biologically harmless.
To avoid damage caused by high pressure all valves and couplings are pressureless when changing tubes or connections.
A mix of air and hydrogen (oxyhydrogen gas) is explosive in a concentration of 18-60 volume percent H2. For this reason, hydrogen is stored outside, where the concentration will never reach critical levels. The pressure vessels are object to inspection at manufacturing and installation according to the European Pressure Equipment Directive (PED). The hydrogen equipment is inspected annually according to local regulations.
Modern and individually designed digital control systems and sensors monitor the overall chain from hydrogen production and storage to combustion and powertrains.
The Green Cycle
Hydrogen storages are an excellent mode of storing energy as alternatives to batteries. Hydrogen can be generated from water by using green electricity from renewable energy sources as solar power, wind power, wave power, hydropower, and geothermal energy. Hydrogen contains a lot of energy, 120 MJ/kg, compared to 40 MJ/kg for diesel fuel and 20 MJ/kg for methanol. Storage losses are neglectable compared to batteries, which compensates a lower rate of efficiency. The only emissions on the green hydrogen cycle are vapor and oxygen.
DIESEL FUEL (MJ/kg)
Our world needs energy supply that allows us to live the life we are used to, just much greener and much more sustainable. Compared to batteries hydrogen technology does not demand as many rare and hazardous metals and heavy constructions. The infrastructure is local and not as vulnerable as national power grids. Transportation takes place in tanks, tubes or via pipeline.
Hydrogen can also be used to generate green ammonia for ships. The only emission is nitrogen gas, the main component of our atmosphere. Combination of hydrogen with carbon dioxide from steel or cement mills will generate synthetic methanol, so called e-fuels, which reduce total emissions when used as fuel.
The European Union will invest 430 billion EUR into hydrogen projects for power generation, heat and transportation (trucks, buses, trains, ships, cars, work machines, aircraft). All over the world research and development projects are initiated to promote usage of hydrogen. Swedish Solar HydroGenesis is a part of this movement. During the last 18 months the number of companies and persons engaged in the hydrogen sector has quadrupled. Green hydrogen is in the focus of this development – banks and other investors compete to invest their funds in a future, clean energy system, a true Game Changer that can be compared to the breakthrough of the smartphone and Internet.