Hydrogen is the new solar nowadays. The claims about its practicality and cost-efficiency are quite bold. The plans built upon those claims do attract many investors also. The investments concerning the hydrogen-related energy infrastructure and systems are expected to rise dramatically. According to the IHS Markit, $44 billion will be invested in green and blue hydrogen projects in five key European countries: France, Germany, Italy, Portugal, and Spain by 2030. The coloring of the hydrogen and its features will be the focus of this article.
Hydrogen is indeed a good option for making the world more decarbonized in the following years, especially for the heating emissions. Those emissions consist of about 40% of energy-related carbon dioxide emissions of the total global carbon emissions. And renewable energy production is unlikely to help that piece of emission since most of it comes from fossil fuel consumption. That is where the "Green Hydrogen," the most famous color of which psyches many environmentalists and government bodies, comes into the stage. They do believe that the green hydrogen will enable them to reduce heating-related emissions, which is really hard to reduce directly. There are other ways to reduce emissions, of course, like crediting and selling them, but those are all indirect solutions, which is the best that the policymakers can provide. When science makes its move and zero-emission fuels are on stage, the potential carbon crediting portfolio will go down. It's not a year's transformation but decades.
Before we explain the coloring, let's give a sneak peek at the code green. Green hydrogen can simply be defined as the hydrogen produced with green energy. Suppose that you have a windmill operating with a significant capacity factor and want to produce green hydrogen. Simply buy an electrolysis device from a manufacturer, find a water source, zap it with your wind electricity, and voila! You have successfully produced green hydrogen. Burn it in your boiler and heat up your home with zero-emission. The problem is solved for heating emission prevention in the most island mode level.
However, when it comes to the question of this concept's price, the potential investors' faces drop instantly. Because it is quite pricey (about €2.5-5.5/kg) and their rate of returns is not that welcoming. Still, it is on a constant downslide, and many are hopeful about the pricing in the future. The upcoming carbon taxation mechanisms seem to help since taxations become more expensive than the production prices of hydrogen. For near ambitions, the hydrogen still stands out as viable heating and heat-intensive business' fuel, but the color is changing with viability. Now, let's take a look at those colors:
Gray hydrogen is made using fossil fuels like oil and coal, which emit CO2 into the air as they combust. The CO2 is released into the air, and because of that, it is coded as grey. This accounts for roughly 90% of the hydrogen produced in the world today. The median price of gray hydrogen is roughly €1.5/kg at the time being.
Blue hydrogen is the hydrogen made from natural gas. When natural gas becomes hydrogen and CO2 either by a Steam Methane Reforming (SMR) process or Auto Thermal Reforming (ATR), CO2 is released as a byproduct. Then it is captured and then stored, unlike the gray one. As the greenhouse gasses are captured, this mitigates the environmental impacts on the atmosphere. The capturing is done through a process called Carbon Capture Usage and Storage (CCUS). This technology is still being developed, and the installation prices are constantly dropping. The median price of blue hydrogen is roughly €2/kg at the time being.
Green hydrogen is hydrogen produced by splitting water by electrolysis, as we did in the primary schools. This electrochemical process produces only hydrogen and oxygen. We can use the hydrogen and vent the oxygen to the atmosphere with no negative impact, unlike gray or blue hydrogen.
To achieve the electrolysis, we need electrical power. If the brightest color of green is wanted, electricity must come from zero-emissions also. This leads us to renewable energy sources, such as wind or solar. This obligation makes the green hydrogen more expensive too. Thanks to the falling prices in renewables, it also reflects into green hydrogen because the electricity prices directly affect the progress of the green hydrogen. The median price of green hydrogen is roughly €4/kg at the time being.
As we examined the colors of the hydrogen in the most basic ways, the question stands still. Which road will the policymakers of the world take for the world? There seem to be enough resources in the world in money, accumulated mostly in developed countries, to make this green transition real. They released a lot of carbon into our atmosphere in the last age in order to make themselves industrialized and developed. It is an excellent time to pay their debts to nature in money to make their development right.