One promising solution to the problem of carbon emissions and Global climate change is the direct use of renewably generated hydrogen in fuel cells or in internal combustion engines for transportation and electricity generation. Although the most common element in the universe, Hydrogen isn’t found in its purest form and must be either electrolysed from water or stripped out of natural gas by means of steam methane reforming. Both are energy intensive processes that result in greenhouse gas emissions. Using electricity in a process called electrolysis splits water into hydrogen and oxygen. The hydrogen is then removed, compressed, transported and used effectively.
Wind Turbines & Green Hydrogen Production
Green hydrogen starts with wind. Lots of wind. Harvesting wind offshore on a massive scale can produce stable green hydrogen on a large scale quickly. By combining wind turbines to hydrogen production there is a synergy that mitigates the energy intense electrolysis process. A substantial proportion of offshore wind farms could eventually make hydrogen rather than transmit electricity. Safe hydrogen exhaust using effective and suitable ventilation will be a key factor in designing these emerging renewable electrolysis technologies.
For wind to hydrogen generation, the systems work by linking wind turbines to electrolysers which pass the wind generated electricity through water to split the liquid ions into hydrogen (to the cathode) and oxygen (to the anode). The hydrogen can then be stored and used later to generate electricity. The only by-product of producing hydrogen is water. Currently wind turbines produce huge amounts of energy with much of that volume going to waste as the grid cannot use it fast enough. In wind to hydrogen initiatives this energy produced from wind farms would be used efficiently to produce hydrogen, meaning none of the electricity produced would go to waste. Current developments are allowing researchers to work on increasing the efficiency of wind to hydrogen systems. When a wind turbine is co-located with the electrolysis system, more direct connection between the source and the electrolyser stack is possible, this eliminates the need for long distance cables and transportation, resulting in a much more cost effective and efficient system. The technology has the potential to deliver a completely emission free, climate-friendly method of making, storing and using energy in the future and as wind turbines are placed further out to sea, hydrogen production close to source becomes even more attractive.
Key Fact: The Global demand for hydrogen is 75 million tonnes and is likely to rise sharply
Is it an ATEX Application?
Most wind to hydrogen systems will incorporate combustible gas detectors that monitor the air flow from the generation cabinet in addition to the compression building air make up, and will shut the system down if a set % of the lower flammability limit of hydrogen in the air is reached. The lower flammability limit of hydrogen in air is 4% by volume. ATEX fans are required if situated in the gas zone containing hydrogen. Typically, an exhaust fan installed in the production and compression building would run continuously during production to avoid a potential build-up of the combustible hydrogen gas. A differential pressure switch on an exhaust fan that indicates proper airflow can be used to inhibit the operation or the electrolyser and compressor ensuring safe working conditions. One of the largest consumers of ancillary power may very well be the fan that continually forces fresh air through a generation cabinet so choosing the most efficient industrial fan to suit the system is important. Industrial fans are required for cooling system components to prevent overheating and additional fans may be used to continuously purge the building for safety.
