System

The system for which the feasibility is studied consists of wind turbines supplying electricity to small remote communities of Greenland to replace current diesel generated electricity supply, Energy surplus from wind in off-peak times is supplied to a green hydrogen production system, the hydrogen produced is then used to generate electricity during peak demand in a system known as Green Hydrogen Combined Cycle Power System .

Challenges with the feasibility of similar systems

Efficiency: The overall efficiency of the system is vastly reduced due to losses across the multiple stages of the system where wind energy is converted into hydrogen and then hydrogen is converted back into electricity [11]. This involves AC/DC conversion, electrolysis, generator efficiencies.

Economic Feasibility: The inefficiencies mentioned above combined with the high capital cost of electrolysis units [12] and the cost of constructing combined cycle systems make the feasibility of such systems still questionable [13].

40 %

A typical green hydrogen combined cycle power plant is only about 40% efficient, after electrolysis and reburning for electricity, and is a viable option for energy storage for longer term.

Wind's Advantages

Greenland possesses a vast potential for onshore wind, with a recent estimate suggesting that if only 20% of ice-free land area was used for wind energy that will generate a theoretical onshore capacity of 333 GW, but wind resources tend to vary from a location to another [7]. Wind is by far the renewable energy with the highest potential in Greenland, and it has a lot of advantages over other renewables for decarbonizing electricity in the small towns still reliant on oil.

These advantages include:

Flexibility, Modularity and Scalability: Wind turbines can be installed in various capacities depending on the community’s needs, small scale installation can be scaled up or down over time depending on the demand, such installations can vary from a single small wind turbine to a wind farm.
Speed of Installation: Small-scale wind energy projects are much easier to be installed and deployed compared to hydropower plants, they can become operational in a matter of months.
Less Infrastructure Required: Large-scale construction requirements like dams and reservoirs, and extensive water management and monitoring needs associated with hydropower are not required for wind projects.
Cold Weather Performance: Wind is less likely to see any performance drops under harsh cold weather conditions compared to solar panels.
Higher Energy Density: The more energy produced per square meter of land in the case of wind compared to solar is advantageous in small towns where the area available is often limited.

Is Hydrogen Viable for Energy Storage?

To achieve 100% renewable electricity in these small communities, a backup system must be integrated with the wind turbines, this backup system will come to work when demand is off peak to provide electricity when conditions are not favorable for the renewable energy being stored. Currently, there are multiple technologies available for renewable energy storage, including:

Pumped Storage Hydroelectricity: energy is stored in the form of gravitational potential energy of water that is pumped from a lower elevation reservoir to a higher one to store surplus electric power when demand is off peak. It is the most developed out of all storage technologies, but large-scale energy systems are required for feasibility to be achieved and to justify the capital costs associated with it, and hence, it is not suitable for the small-scale energy projects being considered [8].
Battery Storage Systems: chemical processes are employed to store generated renewable electricity in a rechargeable form, and hence, they are charged during times of excess production and then discharge during peak demand. Most common battery technologies used for storing renewable energy are lithium-ion, lead acid and flow batteries. S&P expects that by 2040, global battery storage capacity would reach a staggering 942 GW, thus making it the most promising of all storage technologies [9], It is included in parts of this study for comparison reasons. Included in our study for comparison
Green Hydrogen: An electrolysis process is used to split water into Hydrogen and Oxygen. The hydrogen can then be burnt in a hydrogen powered generator to produce electricity during times of peak demand. This system is called a Green Hydrogen Combined Cycle, and it is currently considered a viable long term energy storage, but it is facing a lot of challenges efficiency wise [10]. This is the backup system for which the feasibility is studied.

References

[7] R. S. D. K. C. B. Tansu Galimova, "Sustainable energy transition of Greenland and its prospects as a potential Arctic e-fuel and e-chemical export hub for Europe and East Asia," Energy, vol. 286, 2023.

[8] D.-I. M. Popp, "Storage for a secure Power Supply from Wind and Sun," Berlin, 2010.

[9] A. Franke, "Global battery storage capacity to reach 100 GW by 2025: BNEF," 2018. [Online]. Available: https://www.spglobal.com/commodityinsights/en/market-insights/latest-news/metals/110818-global-battery-storage-capacity-to-reach-100-gw-by-2025-bnef. [Accessed 18 March 2024].

[10] L. Collins, "Why hydrogen-fired power plants 'will play a major role in the energy transition'," 2021. [Online]. Available: https://www.rechargenews.com/energy-transition/why-hydrogen-fired-power-plants-will-play-a-major-role-in-the-energy-transition/2-1-1045768. [Accessed 16 March 2024].

[11] International Energy Agency, "The Future of Hydrogen," IEA, Paris, 2019.

[12] The Clean Energy Finance Corporation, "Australian hydrogen market study: Sector Analysis Summary," 2021.

[13] Hydrogen and Fuel Cell Technologies Office, "Funding Selections for Clean Hydrogen Electrolysis, Manufacturing, and Recycling Activities under the Bipartisan Infrastructure Law," 2024. [Online]. Available: https://www.energy.gov/eere/fuelcells/bipartisan-infrastructure-law-clean-hydrogen-electrolysis-manufacturing-and-0. [Accessed 18 March 2024].