What is Green Hydrogen?

what is green hydrogen

Hydrogen is definitely the trend of the day as the fuel of the future, and yes there is a lot of buzz around it. In this note, we will try to clarify what is Green Hydrogen & why is it so important. and why at this point in time it is not where it should be, and what is needed to make a fully “Green” alternative to fossil fuels.

Green Hydrogen vs. Blue or Gray

Probably here & there you have heard a lot about different colors attached to the word Hydrogen, but why is that? What is actually the difference between Green Hydrogen and the rest? The simple answer is that the color label is simply labeled due to the production method and the energy used to produce the Hydrogen fuel cells. Some time back we had an article on the topic of different methods of Hydrogen production which dives into the discussion.

Type of HydrogenEnergy type used in Production
Green HydrogenRenewable Energy Sources (Wind, Solar, Hydro, etc)
Blue HydrogenFossil Fuels + Carbon Capture & Storage (CCS)
Grey HydrogenFossil Fuels
The energy used to produce the H2 (Hydrogen) defines if it is Green Hydrogen, Blue Hydrogen, or Grey Hydrogen

For now, here we keep it simple. If you use renewable energies to produce H2, you have Green Hydrogen, if you are using fossil fuels to power the process, together with mitigating approaches such as Carbon Capture & Storage (CCS), then it is Blue Hydrogen and if you do it the old fashioned way with only fossil fuels, it will be labeled Grey Hydrogen. The infographic below also shows this in a simple way.

It is the Hydrogen production power source that decides if a Hydrogen fuel cell is Green or not
It is the Hydrogen production power source that decides if a Hydrogen fuel cell is Green or not ( Source: solaredition.com)

Green Hydrogen share in the market, The Status Quo

IRENA tells us that “As at the end of 2021, almost 47% of the global hydrogen production is from natural gas, 27% from coal, 22% from oil (as a by-product) and only around 4% comes from electrolysis. Electricity had a global average renewable share of about 33% in 2021, which means that only about 1% of global hydrogen output is produced with renewable energy” [5]. This shows how dramatic is the situation & there is only one way to turn this around if we intend to count on H2 as a renewable fuel of the future.

Offshore Wind & Hydrogen, the natural pair

Offshore Wind farms however have the potential to turn this around. How is that so? Well, offshore wind farms are placed in the middle of the sea and they can have a power capacity of up to several GW electricity. As they are in the sea, they also do have natural access to an unlimited amount of water. Power + Water + Electrolyser technology means the unlimited capacity to produce H2 and Hydrogen Fuel Cells that can e.g. be stored in H2 tanks in the sea bed, as the deep purple project from Norway suggests (see image below).

The conversion of seawater to Hydrogen happens inside the windmill & then pushed down to seabed tankers (image from Deep Purple Project)

What makes this even better idea is that a big portion of the investments in Offshore Wind Farm projects is on the transition of generated power back to the land where it can be utilized (AC or DC projects). However with having Hybrid Offshore Wind Farms Hydrogen Stations, one can simply save all that money !!!

Advantages of Offshore Wind Hydrogen Station

So let’s review the key points here:

  • Local availability of high amounts of power (18 MW x 1 WTG, GW scale Wind farms)
  • Wind availability is not an issue anymore (produce H2 when there is wind)
  • Unlimited amount of water supply from the sea
  • Grid Solution, where no transition of power is required (saving)
  • Floating Wind Farms can be located even further in the sea, as the transition is not an issue anymore
  • Any others? Please comment with your ideas

Disadvantages of Offshore Wind Hydrogen Station

  • Sea water can not be directly used to produce H2 and needs to be treated
  • Transportation of the fuel cells could be a logistic issue, which can be resolved
  • Any others? Please comments with your ideas

The Hydrogen Fuel Cell, Available & Reliable

We talked about it how Hydrogen is the trendy fuel of the future, but how does it exactly work & how available is it? H2 is in the air and is also a part of the water (which covers 71% of the earth), this makes creating Hydrogen from water (Water Electrolysis) a very simple process. Hydrogen or H2 is packed into energy packs, and fuel cells, which can later be used to produce electricity or heat. Wikipedia tells us that “A fuel cell is an electrochemical cell that converts the chemical energy of a fuel and an oxidizing agent into electricity through a pair of redox reactions.”.

Meaning that Hydrogen fuel cells can be packed and transferred to different locations, and stored and almost be as flexible as fossil fuels. Something that is not so easy for renewable energy sources such as solar and wind as they can be present at a point, but not when they are exactly required (availability & reliability). So using renewable energy resources to produce Green Hydrogen, increases their availability & reliability.

Fuel Cell Structure
Fuel Cell Structure ( Source: solaredition.com)

Applications

Due to the facts that we went through here, Hydrogen is already welcomed in various applications such as

  • Automobile Industry
    Hyundai Nexo SUV (my friend is an extremely happy owner) and Toyota Mirai are already available commercially in the market
  • Logistics
    from busses to trucks, ships and even planes are being modified to fit the fuel cells technology instead of fossil fuels. In a fact, Airbus & Boeing have prototypes and are working on commercial plans with Hydrogen as a fuel [3].
  • Industry & much more
    Hydrogen is being used and planned for wider use as we speak. The industry is counting on the technology so much that even Offshore Oil & Gas production sector is counting on it to make wind power more reliable for Green Oil production in the North Sea. See our article on Deep Purple project.
Energy is stored in form of Hydrogen in seabed & turned to energy when “needed”
Energy is stored in form of Hydrogen in the seabed & turned to energy when “needed” ( Source: solaredition.com)

Did you know?

Wind Edition publishes this trending top 10 Wind Turbine Generators article quarterly. In addition to that, we also have an interactive map of all major offshore wind farms globally.  

our other website solaredition.com also publishes the best solar panels monthly since 2019. In addition to this, we also publish a top 10 72 cells solar panels for industrial scale every quarterly (Q1,2,3,4).

References

[1] Wikipedia, Fuel Cell, URL: https://en.wikipedia.org/wiki/Fuel_cell

[2] Wikipedia, Hydrogen Vehicles, https://en.wikipedia.org/wiki/Hydrogen_vehicle

[3] Airbus ZEROe, URL: https://www.airbus.com/en/innovation/zero-emission/hydrogen/zeroe

[4] Solar Edition articles on topic of Green Hydrogen, URL: https://solaredition.com/?s=%22fuel+cell%22

[5] IRENA, Hydrogen, URL: https://www.irena.org/Energy-Transition/Technology/Hydrogen#:~:text=Electricity%20had%20a%20global%20average,is%20produced%20with%20renewable%20energy.