Energy for the Future

Coinage of the catchphrase ‘climate change’ to substitute for ‘global warming’ was the turning point in the last quarter of the 20th century when it was accepted that the well-established characteristics of various types of climate systems around the world are likely to experience unexpected or anomalous variations in the wake of continued warming.

This realization triggered thoughtful deliberations on adjusting to such abrupt changes in climate manifested by prolonged and severe droughts, floods, hurricanes, and other such disasters. Two new approaches, adaptation, and mitigation, were internationally accepted for humans to survive in changing weather patterns. Agenda-21, UN conventions on climate change and biodiversity, the establishment of UNEP, and COPs are all outcomes of the landmark 1992 Rio Summit.

A steep rise in the world’s total annual carbon emissions trajectory was noted after the 1950s due to massive industrialization powered by extensive use of coal and hydrocarbons. By 1950, the world was emitting 6 billion tonnes of carbon annually, which by 1990 jumped to 22, denoting a three-and-a-half times higher growth rate.

Since the 1990s, emissions have somewhat levelled and currently stand at 34 billion tonnes, showing half as much increase over 30 plus years. This roughly works out to a staggering 1.5 trillion tonnes of carbon in the atmosphere, which a proportional rise in carbon sinks like forests has not balanced. The adaptation approach includes the wilful replacement of coal with natural gas and other renewable sources in the industrial, transportation, and power generation sectors.

In the hope of reducing carbon emissions to control further warming of the atmosphere, other renewable energy sources have since been identified and increasingly used for power generation. Coal and petroleum are giving way to solar and wind power gradually. However, this is not enough to curtail emissions. That’s where hydrogen fits in as a green energy source, with zero carbon emissions, for electricity generation, heating, and energizing industrial or transport sectors.

As hydrogen does not exist freely in Earth’s environment, it is a ubiquitous component in many naturally occurring organic and inorganic compounds such as water, natural gas, coal, organic waste, biomass, etc. Therefore, its production requires securing it from such materials by breaking the bond between hydrogen and other element(s). For large-scale hydrogen production, two methods are commonly used, i.e., steam methane reforming and water electrolysis. In the earlier process, high-temperature steam is mixed with natural gas under high-pressure conditions to secure hydrogen and capture and store carbon. In the second method, an electric current is passed through water to break the bond between hydrogen and oxygen with no emissions.

Hydrogen is a colourless element. However, when using it as a source of energy from different sources, colour codes, such as green, blue, grey, turquoise, white, and brown, denote various levels of carbon emission associated with the source and process of securing hydrogen. In this context, green hydrogen is produced from the electrolysis of water, which has no carbon, and no emissions are made from renewable energy sources. Blue hydrogen is the hydrogen separated from the natural gas, which essentially contains carbon, but the process captures and stores carbon. Hence, there are no emissions.

Grey hydrogen is also produced in the same way as its blue shade, but the system cannot capture and store carbon, which leads to emissions. Brown hydrogen - the opposite of green, is produced from coal gasification and produces significant emissions.

As of 2022, with 96 green hydrogen production units, Australia tops the list, and by 50 units, Spain and Germany fall in second place, followed by the Netherlands, the UK, the USA, Russia, Portugal, China, and Chile. On the other hand, China is the leading consumer in the hydrogen market and developed the largest fleet of fuel-cell electric vehicles, and improved the capacity of electrolysers used for splitting water. The current cost of hydrogen in the international market ranges from 3 to 6 US$ per kilogram, which makes it an expensive and less affordable commodity than natural gas. About 99% of the world’s hydrogen production is coded as grey or blue to make it cheaper.

Hydrogen is a colourless element. However, when using it as a source of energy from different sources, colour codes, such as green, blue, grey, turquoise, white, and brown, denote various levels of carbon emission associated with the source and process of securing hydrogen.

Modification of transport vehicles, so far limited to the extent of cars and busses, from internal combustion engines using gasoline, diesel, CNG, or LNG to electric motors using hydrogen fuel cells, is rapidly advancing in many countries of the world, including China, Japan, South Korea, Germany, Australia, and the USA. Switchover to hydrogen energy required establishing an extensive infrastructure network comprising multiple production units, transmission pipelines extending over large distances, and refuelling stations to make hydrogen a viable alternative to natural gas. Besides road transport, maritime vessels and airplanes can also be transformed to use hydrogen as a fuel in the future, subject to its broader and cheaper availability worldwide. Hydrogen applications are already quite common in petroleum refineries, steel, and fertilizer (ammonia) industries.

Despite the growing use of hydrogen in road transport and industrial sectors, numerous challenges stand in the way of a complete switchover to hydrogen and ensuring net zero emissions. These include reducing the cost of green hydrogen production, efficient, cost-effective as well as safe storage and transportation, investment in building refuelling stations and transmission pipelines, reducing energy losses along the supply chain, developing safety standards and protocols, incompatibility of existing infrastructure and equipment to hydrogen, and lack of consistent policy and regulatory a framework to build the confidence of investors. Until these financial, technological, and regulatory challenges are resolved, the inflow of investment will remain stagnant, and the dream of net zero emissions will be unfulfilled.

In South Asia, India is the first country to announce its ‘National Green Hydrogen Mission’ early this year, aiming to attain 5 million tonnes of green hydrogen production per year by 2030 and achieve net zero emissions by 2070. However, at the same time, the Indian Government has set an acceptable limit of 2 kg of carbon emissions per 1 kg of hydrogen to brand it as green hydrogen in line with their plan to invest US$ 730 billion in coal gasification projects up to 2030. It means whatever quantity of hydrogen is produced, carbon dioxide emissions will be twice as much; thus, the target of net zero will never be achievable. Pakistan, Bangladesh, Sri Lanka, Afghanistan, and Nepal have also focused on developing green hydrogen production plants and ancillary infrastructure by 2030. However, it still seems far from developing their full potential.