The energy landscape is not just changing but completely transforming. With strong commitments from governments and organizations to decarbonize and reduce emissions, industry is racing to find cleaner sources of energy and better ways to use it.
One clean energy option that receives a lot of hype is hydrogen. On the positive side, Hydrogen is already used in fuels and chemicals and has the ability to act as a replacement for natural gas, liquid fuels and coal in existing applications. However, it has become a popular solution looking for a problem to solve.
Despite hydrogen’s benefits, renewable energy is bringing down electricity prices, energy storage is becoming cheaper, and the economy is electrifying. While it is a clean-burning fuel, hydrogen has some considerable disadvantages that still make it an uncompetitive solution in many applications:
- Hydrogen has poor volumetric energy density
- Clean hydrogen is energy and resource intensive
- Using hydrogen requries new infrastructure
Hydrogen takes up a lot of space
Although hydrogen is the most energy-rich fuel per unit of mass, hydrogen is not a dense element at ambient temperatures, giving it a low energy to volume ratio at room temperature. Therefore, storing sufficient amounts of hydrogen can be space intensive, or energy-intensive if stored as compressed gas or in liquid form.
Difficulty around hydrogen storage limit its potential to scale up at points of end-use. Complications around storage also make hydrogen fuel disadvantageous in all but the most challenging transportation applications.
Storing and re-using hydrogen could end up only being the domain of large utility or chemical companies. Potential uses might be to support electricity grids in periods of wind or solar droughts, providing security to hydrogen pipelines, or replacing LNG and coal when shipping large amounts of energy around the globe.
Clean hydrogen is energy and resource intensive
Hydrogen is very abundant, but it mainly exists in compound form with other elements. Isolating the hydrogen elements requires energy. Most of the hydrogen production is done through steam methane reforming (SMR) of methane (CH4), an energy-intensive process that produces CO2 and other pollutants.
A small percentage of hydrogen production is currently done through electricity driven electrolysis, which uses electrical current to split water into its oxygen and hydrogen atoms. This process produces clean hydrogen when the electricity generation comes from renewable energy sources such as solar or wind energy. With that said, the financial viability of this process depends on low capital and electricity costs, and high system efficiency.
In addition to electricity, hydrogen production through electrolysis requires freshwater. Estimates suggest that nine litres of freshwater are needed to produce a kilogram of H2. The energy and water intensity increase if the water needs desalination.
The process of generating electricity from renewable energy sources, converting it to hydrogen for storage and transport, and then reusing the hydrogen results in significant losses. With this supply chain energy loss, it will make sense to use electricity directly if technically possible for many end-use applications.
This is illustrated well in the passenger vehicle example. Starting with a clean electricity source, electric vehicles achieve a 70-90% ‘Wind-to-wheel’ efficiency compared with 25-35% for hydrogen fuel-cell vehicles. All the other supposed benefits of a hydrogen system will have to out-compete the fundamental driving force of lower operating costs for electric vehicles.
Using hydrogen requires new infrastructure
Hydrogen can be transported using trucks and trains, but the majority of natural gas pipelines are not well-equipped to move hydrogen. As a small molecule, hydrogen can leak through pipes and embrittle metals. In addition to a network of piping, transporting hydrogen will also require investment into technologies that can compress, dispense, and purify the hydrogen.
There is talk of blending hydrogen with natural gas to transport it throughout natural gas pipelines, but due to the lower volumetric energy density of hydrogen and the increased amount of work needed to transport it throughout the pipeline network, this solution hardly makes sense.
The Role of Clean Hydrogen
Considering its downfalls, clean hydrogen will not be desirable for many applications as electrification brings massive improvement in energy efficiency. Nevertheless, there are processes that cannot be electrified, so clean hydrogen will likely have a role to play in the places that electricity cannot reach if we are to become a net-zero carbon society.
Steel manufacturing — The majority of global steel production is made using a blast furnace and basic oxygen furnace. Using carbon as a reducing agent to remove oxygen from iron ore, the blast furnace is the largest source of direct carbon dioxide (CO2) emissions within the steel production process. Therefore, replacing carbon with hydrogen as the iron ore reducing agent avoids the creation of CO2 as a byproduct.
In addition to being the reducing agent, hydrogen can be burned to generate the high process heat needed for steel production.
This steel production process using hydrogen as the fuel source and reducing agent — a process known as HYBRIT — is currently being developed in Sweden with aims of producing fossil free steel around 2026.
Chemical feedstocks — Hydrogen is already used as a significant feedstock for the chemical industry, namely for ammonia production and refinery processes. Hydrogen production has increased substantially over the decades and considering the majority of hydrogen is produced through the carbon intensive process of SMR, clean hydrogen could step in as significantly cleaner alternative.
Trends suggest a growing demand for hydrogen, so the best way to decarbonize these chemical manufacturing and refinery processes is through the implementation of clean hydrogen.
Long distance shipping — Hydrogen won’t make a great fuel source for aviation based on safety concerns and energy density. Hydrogen can, however, serve as a viable fuel source for long distance shipping. Such vessels are not constrained by the same size parameters, and long-distance shipping routes will be more effectively fueled by burning hydrogen or a hydrogen derivative fuel than by running off electricity and battery storage. Hydrogen may compete most in the new-build space, with biofuels or other e-fuels helping to transition the existing fleet in the shorter term.
Large scale energy carrier – in some chemical form or other, Hydrogen will be an energy carrier between nations. The global LNG trade has proven that inter-country trading of energy benefits energy security. Japan and Korea have significant hydrogen import strategies, whilst countries like Australia have Hydrogen export plans. This should be encouraged, as some countries with few natural resources have little choice but to import additional clean energy in order to meet net zero goals. Building new infrastructure for such large scale, concentrated point-to-point energy transfers makes more sense than trying to distribute hydrogen to households to make hot water, or using it in cars while losing 75% of the energy from the source to end use.
Clean Hydrogen will be used for many applications — for steel, as a chemical feedstock, in very long-distance transport, and as an international energy carrier. This versatility will mean it has a bright future.
For many of our industrial customers, clean hydrogen will never be cheaper or more convenient than energy efficiency improvements, other renewable energy sources, or energy storage (either electric or thermal).
In the end, clean hydrogen will have a major part to play, but it won’t be the one solution that saves us all.
At Northmore Gordon, we help businesses navigate the changing energy landscape so that they can make strategic investments that make sense now and over the long run. If you are interested to see how hydrogen fits into your strategic energy plan, make sure to reach out so that your business can be informed and stay competitive.