Green hydrogen is a flexible, zero-emission fuel for energy production and storage. Green hydrogen's widespread acceptance would considerably help the worldwide energy grid transition away from fossil fuels and decarbonize our industries. However, its higher production costs could stymie the green hydrogen revolution before it begins. This article will consider the prospect of replacing natural gas with green hydrogen, a significant but complex step toward sustainability.
The Problem with Natural Gas
Natural gas is composed chiefly of methane, which emits carbon dioxide when burned. Natural gas accounts for 22% of global fuel combustion emissions, comparable to gasoline's 32% and coal's 45%. Natural gas heating accounts for around one-third of all greenhouse gas (GHG) emissions. We must address gas' contribution if we hope to attain the Paris Agreement objectives of a 75% reduction in GHG emissions by 2035 and net-zero emissions by 2050.
How Green Hydrogen Is Made
Green hydrogen comes from using renewably powered electrolysis on water. The electrolytic process divides the H2O molecules, and the final output of the reaction is oxygen (O2) and hydrogen (H2). The hydrogen is then captured and stored for use as fuel. Because the electricity comes from a renewable source, the entire process, including combustion, is carbon and GHG-free.
Obstacles to Replacing Natural Gas with Hydrogen
Although green hydrogen is a perfect chemical replacement for natural gas, there are several impediments to a complete transition from gas. Ultimately, it comes down to costs, some obvious, others hidden.
Green hydrogen is around four to five times the price of natural gas, sometimes higher. Aside from the high expense of producing green hydrogen, constructing an infrastructure to transfer it to thousands of potential standalone filling stations presents additional challenges. A new hydrogen pipeline network requires substantial upfront capital investments, and the properties of hydrogen present particular issues in the design of pipeline components.
Hydrogen has a lower energy density than all other fuels, making storage and transportation to the point of use more costly. Using green hydrogen to decarbonize heavy industries would require tremendous power. The only option to fulfill this need is to increase renewable energy output. Due to this increase, significant infrastructure design issues will arise, such as prioritizing H2 pipes and transmission lines.
Enabling the fast spread of hydrogen infrastructure will require the development of an incentive structure to promote capital investment and system-wide infrastructure planning - both costly ventures.
The primary challenge with hydrogen distribution is that gases must be compressed to be delivered efficiently. It takes around three times the energy to compress the same amount of hydrogen as natural gas. This threefold increase in compression would be expensive, requiring the upgrading of each compressor to a bigger one with three times the capability.
Reactivity and Leakage
Because hydrogen has different properties from natural gas, the quantity of hydrogen fuel that can be mixed into conventional pipeline systems is small. Moreover, since hydrogen is the lightest and smallest molecule in the environment, it may easily escape from pipes and other components of the gas network meant to carry bigger natural gas molecules. Finally, hydrogen interacts differently with various metals. As a result, it may damage and corrode steel pipes often seen in pressurized gas transmission lines.
Recent Advances in Green Hydrogen
Over the last three years, green hydrogen initiatives have grown fivefold, and multiple projects are slated until 2030, with an anticipated $500 billion in finance and incentives. Official plans for a hydrogen economy exist in Japan, the EU, and Canada.
The US Department of Energy's Hydrogen Shot project seeks to attain $1/kg of green hydrogen fuel by 2030. Similarly, in light of the country's 2060 net-zero target, China's state-owned enterprises have already announced massive green H2 initiatives involving huge 100 GW electrolyzers.
Several European nations are also working on green hydrogen initiatives. In Germany, where the world's biggest electrolysis plant is now operational, hydrogen energy systems are being evaluated as a substitute for natural gas in domestic heating. Moreover, researchers in the United Kingdom aim to replace methane in the gas pipeline infrastructure with H2. Northern Gas Networks in Leeds, UK, is preparing the H21 pilot project. The eventual goal of this initiative is to convert the city's heating system to green hydrogen.
The Past and Future of Hydrogen Fuel
Hydrogen has a long history of use in power generation and industries. In 1807, this gas was used to power the first internal combustion engine. It has since powered vehicles, heavy machines, and spaceships. The urgent requirement for global decarbonization will increase the importance of hydrogen over the next several decades.
To make it easier for investors, governments and businesses must collaborate. Furthermore, standardized worldwide standards for the efficient storage and transportation of large quantities of hydrogen fuel would help speed up the international adoption of green hydrogen.
The Green Hydrogen Revolution Is Waiting on Lower Costs
Green hydrogen is an effective but energy-intensive replacement for natural gas. Although it is currently too expensive to compete with conventional sources of hydrogen and other fuels, the amount of projects incorporating hydrogen has grown in the last several years as investors have bet on the possibility of lower hydrogen costs. If hydrogen production prices fall by half by 2030, as predicted by the World Hydrogen Council, it could become a critical renewable energy source that helps lead us to a more sustainable future.
Don't Wait – Green hydrogen might have to wait for falling prices, but other green energy sources don't. Instead, consider installing solar or opting for wind. Moreover, high-efficiency appliances can further reduce your footprint and save you money over the long haul.
Lower Your Power Draw – Some parts of the country are almost entirely powered by natural gas. If that's the case for you, and you can't make a switch to renewables, do what you can to save power, particularly when it comes to heating and cooling.
Stay Local – Until EVs and Fuel Cell EVs are more common, transportation is at the mercy of the petroleum industry. Consolidating shopping trips and buying local products will reduce the demand for fossil fuels in the supply chain.