Hydrogen is emerging as one of the most viable and effective storage solutions for renewable energy in many key industries, including the transportation and power sectors.
The renewable energy sector currently deals with fluctuating energy supply as a result of the variabilities of the sun and wind. This makes connecting renewables to the AC grid challenging. In addition, the dynamic nature of renewable energy dictates that installed capacity is greater than demand. This means that considerable energy surpluses are produced at certain times, which cannot be absorbed by the main grid.
At present, significant amounts of ‘green’ energy are therefore being discarded. Batteries as a means of energy storage are costly and have limited capacity, while disposal of spent batteries is an environmental challenge.
However, with hydrogen technology, excess power from renewable sources can be fed to electrolysers to generate hydrogen, which can be stored and then used to create energy at convenient times. This so-called ‘green’ hydrogen enhances the business case for renewable energy sources, as the electricity it produces maximises the value of renewable energy systems.
The application of hydrogen as a means of energy storage – or ‘power-to-gas’ as it is known – has been successfully demonstrated in Germany with its advanced renewable energy programme. It is estimated that, by 2050, renewables will provide 80% of that country’s energy.
Existing natural gas networks could serve as a substantial green hydrogen energy storage solution, according to Sales Director for Nel Hydrogen, Eric Dabe. “Up to 5% hydrogen can be bled into and stored in natural gas piped networks,” he says, explaining that this contributes to the decarbonisation of the natural gas grid.
“The calorific value of the resulting gas mix is greater. Less gas can be used to achieve the same result while the net energy benefit is greater than 5%. Blending hydrogen with natural gas also lowers emissions, as when hydrogen is burned, the emissions are pure water.”
The motor vehicle manufacturing and transportation sectors are others where hydrogen technology is receiving heightened attention. With hydrogen-powered vehicles on the rise, there is an increasing demand for hydrogen fuelling stations. Offering the same convenience as their fossil fuel counterparts, the modern hydrogen fuelling station can fill a car in three minutes, to give a range of approximately 600km.
In February this year, Nel Hydrogen Fueling, a division of Nel Hydrogen, announced that it had developed and launched a new multipurpose hydrogen fuelling station. Connected to a single fuelling module, it can serve at least three hydrogen dispensers.
Nel Hydrogen is represented locally by RTS Africa Engineering, which has been responsible for installing, maintaining and supporting Nel Hydrogen electrolysers since the mid-1990’s.
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