Can the Middle East open the door to affordable clean hydrogen?

Image: Ghadir Shaar

A report by the International Renewable Energy Agency (IRENA) has suggested affordable green hydrogen could already be obtainable, based on the record-breaking low prices for solar negotiated in the Middle East.

Solar electricity tariffs of $0.0157, $0.0135 and $0.0104 per kilowatt-hour agreed in Qatar, the United Arab Emirates and Saudi Arabia, respectively, in the last 18 months, would enable renewables-powered hydrogen to be produced for as little as $1.62 per kilogram, according to IRENA's Renewable Power Generation Costs in 2020 report.

The Abu Dhabi-based international body made its calculations – all of which are in U.S. dollars – based on the $0.0104 solar power tariff agreed in Saudi Arabia in April, with green hydrogen generation being modeled at the Dumat al Jandal site in the kingdom which boasts strong solar and wind power resources. With the site already hosting a wind farm, IRENA modeled a hydrogen plant which would also harness solar and be connected to the grid. The report suggested lack of a grid connection would raise the renewable hydrogen cost to $1.74/kg, which still compares favorably to the current $1.45-2.40/kg price of hydrogen production powered by natural gas and equipped with carbon capture and storage (CCS) tech.

Further extrapolating the costs, the study estimated a fall in hydrogen electrolyzer costs, from $750 per kilowatt of capacity to $350, would enable renewable hydrogen production for $1.16/kg. Raising electrolyzer efficiency to 72.5% and extending stack lifetime from 15 to 17.5 on top of that, IRENA said, could take green hydrogen below the prized $1/kg point.

With this year's renewables price report explaining how the three tariffs secured in the Middle East since January 2020 can be regarded as viable without any hidden caveats or subsidy, the authors of the study stated: “low-cost renewable hydrogen may already be in reach.”

The document fleshed out how up to 800 GW of coal-fired power generation capacity worldwide could already be replaced by newly-built renewable energy facilities as solar and wind prices have dipped under the cost of running legacy fossil fuel plants in many markets. That estimate included a $5/MWh cost of integrating renewables into the electric grid and IRENA said, with around 40% of that overpriced capacity – and 37% of actual generation – based in Bulgaria, Germany, India and the United States, decommissioning could save around $32 billion per year in energy costs. Making the switch would also eliminate three gigatons of carbon emissions – 20% of what IRENA estimates is needed to keep global heating to a maximum 1.5 degrees Celsius this century.

The data

The latest edition of the report is based on data from around 20,000 renewables generation facilities worldwide which account for 1.9 TW of generation capacity, and on clean energy auction prices and power purchase agreements which add up to 582 GW of capacity. All the figures in the study exclude any form of subsidy and the authors point out, adding CCS to the world's overpriced coal plants would merely drive up their costs further.

IRENA has estimated all of Bulgaria and Germany‘s coal plants will this year cost electricity bill payers more than new renewables facilities would, based on a European carbon emissions price of €50 per ton. Even without an emissions trading scheme in the U.S. and India, the picture is similar, with 77-91% of American coal plants and 87-91% of Indian facilities also overpriced.

That conclusion is based on an estimated levelized cost of energy (LCOE) for solar power in India this year of $0.033/kWh, down from $0.038 last year; and of $0.031 in the States this year, although the report's authors note the solar module price has picked up between 1% and 9% in the first quarter of this year, thanks to shortages of raw materials such as polysilicon.

With the global LCOE of solar having fallen 7% from 2019 to last year, from $0.061 to $0.057/kWh, India led the world for low-price PV last year, with an average LCOE of $0.038/kWh for utility scale generation, ahead of China, with $0.044, and Spain, with $0.046. The authors noted Turkey also rapidly reduced average solar tariffs, to $0.052 last year, and Australia posted an average $0.057.

That translated into average solar project development costs of $596 per kilowatt installed in India, the world's lowest figure and down 8% from Indian costs in 2019. Solar projects in Vietnam came in to $949/kW and were only $796/kW in Spain last year, the report added. At the other end of the scale, projects in Russia cost $1,889/kW and, in Japan, $1,832, with those two countries exceptional among the 19 markets studied as the cost differences between areas from Canada (at $1,275/kW) down to India, were more evenly distributed.

Auction results posted last year, for projects expected to be commissioned this year and next, prompted IRENA to estimate the global average solar power price will fall to $0.039/kWh this year before rising slightly to $0.04 next year, which would still be a 30% fall on this year's figure and 27% less than the LCOE to be expected from new-build coal plants. With the predictions based on 18.8 GW of renewables capacity expected this year and 26.7 GW due in 2022, the study estimated 74% of the clean energy facilities expected this year and next will be cheaper than new fossil fuel generation sites.

Cheaper

Renewables are already making real headway, of course, with IRENA calculating 45.5 GW of the solar added last year was among the 62% of the 162 GW of clean energy facilities which were installed more cheaply than new-build coal plants.

Digging into the solar statistics, the report said mainstream solar panel costs in December ranged from $0.19 to $0.40 per Watt, for an average price of $0.27, with thin-film products averaging $0.28/W.

Operations and maintenance costs came in at an average of $17.80/kW last year in OECD countries and $9 elsewhere, in a year which also saw non-panel, balance-of-system equipment costs account for 65% of total project expense.

For residential solar arrays, average system prices in the 19 markets studied by IRENA ranged from $658/kW in India to $4,236 in California, for LCOE figures from $0.055/kWh in India to $0.236 in the U.K. For commercial systems, India was again the cheapest place to invest last year, at an average $651/kW, but a business in California would have to find $2,974/kW. Those system costs translated into LCOE numbers ranging between $0.055 in India and $0.19 in Massachusetts.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

A rendering of the project to produce green hydrogen that Gransolar is planning for the Port of Almería.

Image: Gransolar

A company spokesperson told pv magazine that the plant will produce hydrogen from seawater and will be powered by a 30 MW solar plant and a 20 MWh storage system with an autonomy of 4 hours.

The facility will be based on double-reverse osmosis treatment with energy recovery followed by electrolysis of deionized water through proton exchange membrane (PEM). Furthermore, secondary electrolysis of concentrated brine will be implemented by cell membrane electrolysis.

The main electrolyzer at the facility will have an installed capacity of 20 MW and an estimated production of 1,000 tons per year. The produced fuel will be then stored in trucks for pressurized gas at 400 bar pressure.

Hydrogen will be used as fuel for public transport at the port and urban cleaning vehicles in the city of Almería. It will also be utilized to feed the port's unloading machinery, the national and international transport of goods, and part of the energy demand of local manufacturing industries.

The project has a required investment of €80.5 million euros and is scheduled to be built by the end of 2024. Gransolar confirms that it has the interest and commitment of the Almería City Council, as well as multiple companies from different professional sectors, without providing further details.

Almería will not be the only Andalusian port with plans to produce hydrogen. The Port of Malaga is also expected to host green hydrogen production through a project that also contemplates the use of artificial intelligence.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com)

Los Angles skyline

Image by Armin Forster from Pixabay

The Green Hydrogen Coalition, the Los Angeles Department of Water and Power, and other partners launched HyDeal LA, an initiative to achieve at-scale green hydrogen procurement at $1.50/kilogram in the Los Angeles Basin by 2030.

HyDeal LA aims to overcome the biggest barrier to the green hydrogen economy—its high cost—by launching a commercial green hydrogen cluster at scale.

Green hydrogen can be produced from renewable electricity and water or organic waste, can be used as a carbon-free fuel, and provide long-duration seasonal energy storage.

Phase 1 of HyDeal LA will design the supply chain needed to achieve $1.50/kg delivered green hydrogen in the LA Basin. It also will strive to agreen on terms and conditions to achieve production, storage, transport, and delivery of green hydrogen at scale.

LADWP said that green hydrogen “is the key to reliably achieving 100% renewable energy.”  The HyDeal LA effort aims to catalyze the supply chain needed to achieve large-scale, low-cost green hydrogen power supply for LADWP’s local power plants.

In March, a study from the National Renewable Energy Laboratory said that Los Angeles’ goal of reaching a 100% renewable, reliable, and resilient grid could be met as early as 2035. Doing so will require adding new solar, batteries, wind, and transmission, along with operational practices that make more efficient use of those assets. The study did not address specific costs, but said that economic impacts to the city would be “small relative to the overall size” of LA’s economy.

Power plant conversion

LADWP is currently leading the conversion of the Intermountain Power Project in Delta, Utah, to become one of the world’s first gas turbines designed and built to operate on 100% green hydrogen.

Dubbed “IPP Renewed,” Intermountain project includes retiring existing coal-fired units at the power plant site and installing new natural gas-fired electricity generating units capable of utilizing hydrogen for 840 MW net generation output. Additional investment will modernize the power plants transmission system to southern California, and develop hydrogen production and long-term storage capabilities.  The new natural gas generating units will be provided by Mitsubishi Power and designed to use 30% hydrogen fuel at start-up, transitioning to 100% hydrogen fuel by 2045 as technology improves.

HyDeal LA is part of HyDeal North America, a commercialization platform launched by the Green Hydrogen Coalition. It is modeled after HyDeal Ambition, a similar project in Europe committed to producing and buying 3.6 million tons of green hydrogen per year for the energy, industry, and mobility sectors at €1.5/kilogram (kg) before 2030.

In addition to LADWP, HyDeal LA leaders include 174 Power Global, Mitsubishi Power, and SoCalGas. Key implementation partners include Clifford Chance, Corporate Value Associates, Cranmore Partners, Energeia, Marathon Capital, Sheppard Mullin, and Strategen.

Earlier in May, Mitsubishi Power and Texas Brine Co. agreed to develop large-scale long-duration hydrogen storage to support decarbonization efforts across the eastern United States.

This collaboration expands Mitsubishi Power’s capability to store hydrogen in salt caverns across North America. As one of the nation’s largest brine producers, Texas Brine and its affiliates have salt positions in New York, Virginia, Texas, and Louisiana that will enable access to major load centers in the Northeast, Mid-Atlantic, and the Gulf Coast.

Expanding the use of salt caverns for hydrogen energy storage offers an opportunity to create an infrastructure for clean energy resources throughout the U.S. to benefit industries such as power, transportation, and manufacturing that are targeting net zero carbon emissions.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

A hydrogen bus developed by Poland-based Solaris Bus & Coach.

Image: Solaris Bus & Coach

U.S. trading company Tramo, Vienna-based Austria Energy Group and Austrian renewable energy developer Oekowind have signed a memorandum of understanding for the production of a hydrogen/green ammonia plant to be developed in Chile with an estimated annual production capacity of 1 million tons of green ammonia. This project, in Chile, will be one of the first to commercialize green ammonia. It will be based on a 2 GW wind farm.

A team of researchers at the Research Center for Energy Networks and Energy Storage (FENES) of the East Bavarian Technical University (OTH) Regensburg, led by Professor Michael Sterner, is developing a hydrogen atlas for Germany. The interactive, continuously updated database will show which power-to-X plants are installed, indicating also related regional value chains. The project will be built gradually. The final version should be available in 2023. “The hydrogen atlas offers users the opportunity to assess potential, consumption, costs and emission reductions on a regional level,” Sterner explains. “This provides them with a comprehensive tool that facilitates entry into concrete technical planning.”

Canadian integrated energy company Suncor and Canadian holding company ATCO are looking into a potential “world scale clean hydrogen project” in Alberta. The decision follows support messages from the government of Canada and the government of Alberta, both in favor of emission-reduction projects. “Approximately 20% of the produced clean hydrogen could be used in the Alberta natural gas grid to further reduce emissions,” read a note released on Tuesday, adding that the majority would be used in refining processes and co-generation of steam and electricity at the Suncor Edmonton Refinery. The project should produce more than 300,000 tonnes per year of clean hydrogen.

Japanese petroleum company Eneos and Japanese multinational automotive manufacturer Toyota Motor are exploring hydrogen applications at Woven City, a prototype city in Susono City, Shizuoka prefecture. Eneos should establish a hydrogen refueling station and produce green hydrogen. The two companies are also interested in conducting joint advanced research on hydrogen supply. “At Woven City, they intend to promote carbon neutrality in everyday mobility, people's lives, and within the infrastructure of the city itself,” read a statement released on Monday.

Japanese transport company Mitsui O.S.K. Lines (MOL) and Mitsui E&S Machinery are carrying out a joint study to introduce hydrogen fuel port cargo handling machinery. As part of the agreement, MOL signed a “contract for a new, near-zero emission, rubber-tired gantry container yard crane, and decided to introduce it at the MOL-operated Kobe International Container Terminal.”

Professor Kondo-Francois Aguey-Zinsou, who leads the Hydrogen Energy Research Centre (HERC) at the University of New South Wales (UNSW), said that Australia is at the cutting edge of the hydrogen revolution and will increasingly collaborate with other countries. The comment came at the launch of a new hydrogen advisory firm called H2Potential, which will act as an incubator and an accelerator of hydrogen businesses. In collaboration with LAVO, Aguey-Zinsou helped produce the world’s first residential/commercial hydrogen battery, which stores 40 kWh of energy. That’s almost three times the capacity of a Tesla Powerwall 2, which offers 13.5 kWh.

An international alliance of 45 companies, knowledge institutes and port authorities, headed by the Port of Rotterdam Authority, has been awarded nearly €25 million in EU funding, wrote the Port of Rotterdam on Tuesday. “The consortium will be using this grant to execute ten pilot projects and demonstration projects that focus on sustainable and smart logistics in port operations,” read the note, adding that many details are not yet clear. Anyhow, the Port of Rotterdam explicitly mentioned green hydrogen among the potential renewable fuels and energy carriers.

Germany confirmed its interest in funding hydrogen, with both Länder and the federal state looking into projects that could allow the country to become a “global technology supplier.” An example is the hydrogen hub planned in Huntorf by Oldenburg-based energy, telecommunications and information technology company EWE and Dusseldorf-headquartered energy company Uniper. “Green hydrogen is an indispensable building block for the energy transition. That's why we are funding five innovative research projects across Lower Saxony with a total of €6 million. Here in Huntorf, the DLR Institute for Networked Energy Systems and Clausthal University of Technology are now using the compressed air storage power plant to investigate the potential of using green hydrogen in thermal processes,” Lower Saxony's minister for science and culture, Björn Thümler, commented in a note released on Monday.

Poland-based Solaris Bus & Coach has sold 13 hydrogen vehicles to Frankfurt. The buses are to be deployed on target routes in 2022. “The technology used in the Urbino hydrogen [bus] makes for absolutely environmentally friendly transport, thanks to the use of energy supplied by a fuel cell (of 70 kW),” read a note released last week. Earlier this year, the company signed deals for hydrogen buses with companies based in Germany, Italy, Austria and the Netherlands.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

First Solar

First Solar and Nel Hydrogen Electrolyser, a division of Nel ASA, a supplier of hydrogen technology, said they will develop integrated photovoltaic/hydrogen power plants.

First Solar and Nel will initially collaborate to develop an integrated power plant control and Supervisory Control and Data Acquisition (SCADA) system. The development of this network architecture is critical to enable optimisation of PV-electrolyser hybrid projects, resulting in low total cost of hydrogen and electricity. After that, the two will explore  ways of optimising and integrating technology throughout the solar and hydrogen production plant.

In statements, both companies stressed their desire to deliver the lowest total cost of solar to hydrogen possible. Both also noted that First Solar’s low-carbon production of its cadmium-telluride modules was significant for keeping emissions low.

Because the partnership is so recent in nature, no project timelines have been released as of yet.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

Image: Siemens

Within Florida Power & Light’s (FPL) recently-filed four-year rate request with the Florida Public Service Commission is a commitment to “investments to build a more sustainable energy future.”

The pledge in the regulatory filing includes the utility’s “30-by-30” plan to install 30 million solar panels in Florida by 2030, as well as plans to build what the utility said would be the world’s largest integrated solar-powered battery and a green hydrogen pilot project.

The battery system is the Manatee Energy Storage Center, a 409 MW behemoth that could begin serving customers in late 2021. FPL’s Gulf Power unit said on Feb. 25 that it had begun construction on the project. The project is expected to help speed the retirement of aging natural gas units at a nearby power plant.

The green hydrogen pilot project was first announced by NextEra Energy, FPL’s parent company, in July 2020.

NextEra plans to invest $65 million into the pilot, which will use power from otherwise curtailed solar energy to produce green hydrogen via a 20 MW electrolysis system.

It’s worth noting that NextEra ranks as one of the nation’s largest solar and wind developers. So, although a 20 MW pilot may not initially move the needle toot much, NextEra’s vast wind and solar also comes with a lot of curtailed renewable generation. If the pilot proves successful and scalable, the company could look toward a serious buildout of more hydrogen producing facilities that could replace fossil fuels.

For now, the green hydrogen produced as part of the pilot would replace some of the natural gas combusted at FPL’s 1.75 GW Okeechobee power plant. Rather than build a new hydrogen plant, FPL is retrofitting an existing plant to accommodate the fuel source.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

The site where the new salt cavern is being built.

Image: EWE

German energy provider EWE has started the construction of a cavern for hydrogen storage in Rüdersdorf, near Berlin.

The cavern storage facility will have a capacity of 500 cubic meters, which corresponds to the volume of a single-family house. The company is working with the German Aerospace Center (DLR) on this project.

The DLR Institute for Networked Energy Systems will examine, among other things, the quality of the hydrogen during storage and after it has been extracted from the cavern.

In the first stage of the project, EWE will build a derrick on an existing borehole and this work is expected to take a week. The utility will then install and cement a steel pipe from the surface to a depth of 1,000 meters by the beginning of April. This will connect the pilot cavern with the earth's surface.  

“In the context of the research project, we particularly hope to gain knowledge of the degree of purity of the hydrogen after it has been withdrawn from the cavern,” said EWE project manager Hayo Seeba. This factor is crucial for the use of hydrogen in the mobility sector.

The knowledge that the small pilot cavern will provide should be easily transferable to caverns with a volume that is 1,000 times higher, the company went on to say. The aim is to use caverns with a volume of 500,000 cubic meters for large scale hydrogen storage in the future.

EWE owns 37 salt caverns that represent 15% of all German cavern storage facilities that could be suitable for storing hydrogen in the future. “This would mean that large quantities of green hydrogen generated from renewable energies could be stored and used as required and would become an indispensable component in order to achieve set climate targets,” Seeba added. 

Scientists at Germany’s Jülich Institute for Energy and Climate Research (IEK-3) recently revealed that Europe has the potential to inject hydrogen in bedded salt deposits and salt domes with a total energy storage capacity of 84.8 PWh. Most of these salt caverns are concentrated in northern Europe, at offshore and onshore locations. Germany accounts for the largest share, followed by the Netherlands, the United Kingdom, Norway, Denmark, and Poland. Other potential sites are in Romania, France, Spain, and Portugal.

“Germany has the highest storage potential in both onshore and offshore contexts,” the group said.

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com)

Image: Swinburne University

Researchers from Swinburne University’s Centre for Translational Atomaterials and Shaanxi Normal University have developed a novel catalyst that can produce high-performance solar-triggered hydrogen from seawater. If there is one thing that we all know about seawater, it’s that there is a lot of it, so it's no surprise that this  scientific discovery has great potential.

In order to utilize this new catalyst, the researchers had to develop a prototype device, the Ocean-H2-Rig. It can float on the ocean's surface to produce green hydrogen from seawater.

One of the easiest and greenest ways to produce hydrogen is through photocatalytic water splitting, which uses solar energy to split water into its composite atoms, securing the hydrogen and harmlessly emitting the oxygen. The novelty of the single-atom platinum catalyst the researchers have developed is that the photo-generated electrons and holes triggered by solar radiation do not try to recombine, which greatly improves hydrogen production efficiency.

The proposed algorithm was validated on a hybrid system for application in both off-grid and on-grid scenarios.

Image: Frerk Meyer/Flickr

Researchers from Saudi Arabia's Qassim University and the Minia University, and the Aswan University in Egypt, have developed a new model to integrate PV, wind, and hydrogen generation in a hybrid system for application in both off-grid and on-grid scenarios.

The model is based on a metaheuristic algorithm called Improved Artificial Ecosystem Optimization (IAEO), which the scientists claim is an improved version of the conventional Artificial Ecosystem Optimization (AEO) algorithm. The latter is a nature-inspired algorithm known for mimicking three typical behaviors of living organisms, such as production, consumption, and decomposition.

The producers are any kind of green plant and consumers are animals that cannot make their food and, therefore, obtain it from a producer or other consumers. Decomposers are agents that feed on both producers, in the form of dead plants, and consumers, in the form of waste from living organisms. In an AEO algorithm, there is only one decomposer and one producer, and the other individuals are considered consumers.

The AEO works according to these three phases and is commonly used to optimize the flow of energy in an ecosystem on the earth. “The ecosystem can be expressed as a group of living organisms [which] live in a certain space, and the ecosystem describes the relations between them,” the researchers said, adding that IAEO is mainly intended at improving the consumption phase.

The proposed energy system consists of PV and wind power generation, a water electrolyzer, a tank of hydrogen gas, a fuel cell, and an inverter that brings the generated electricity to final consumers. “The hybrid system is suggested to be located in [the] Ataka region, [in the] Suez gulf (latitude 30.0, longitude 32.5), Egypt, and the whole lifetime of the suggested case study is 25 years,” the scientists specified.

In this configuration, which the academics have assessed for both off-grid and grid-connected projects, wind and solar plants are used to power the electrolyzer that produces hydrogen, which is then stored in the tank and used to produce electricity through the fuel cell. The inverter receives electricity from the fuel cell and also surplus power from the wind and solar facilities. “When the level of hydrogen in the tank becomes below the lowest allowable level, the shortage in the electrical energy required to store the hydrogen gas in the tank is dispatched from the national grid,” they further explained.

Both the IAEO and conventional AEO algorithms were applied for generating the optimal design for the system. “In the case of the isolated configuration, when the electrical power produced from PV and wind resources is higher than the load needs plus the rated power of the electrolyzer, a dummy load is used for generation-demand balance,” the Saudi-Egyptian group stated.

The IAEO algorithm was validated in six different configurations of the proposed hybrid system and, according to the research team, has provided better results not only compared to the AEO, but also to other kinds of algorithms. “The proposed IAEO algorithm provides fast convergence characteristics, the best minimum values of the objective function, and minimum cost of energy,” it concluded. “Based on the optimal configuration of the hybrid systems, it is found that the fuel cell system has the highest contribution to the net present cost.”

This article originally appeared on pv-magazine-usa.com, and has been republished with permission by pv magazine (www.pv-magazine.com and www.pv-magazine-usa.com).

The model was presented in the paper An improved artificial ecosystem optimization algorithm for optimal configuration of a hybrid PV/WT/FC energy system, published in the Alexandria Engineering Journal.

Caverns like this one in the Salina Slănic salt mine in Romania could serve as large storage tanks for hydrogen from renewable energies.

Photo: Dan Tamas / Janos Urai

Salt caverns for storing energy from renewable sources have long been in focus. EWE, for example, wants to build a redox flow battery with an output of 120 megawatts in the caverns of a former salt dome near Oldenburg by 2023 . And RWE Gas Storage West GmbH and CMBlu Energy AG have started a joint research project aimed at converting the salt caverns previously used for gas storage into large, organic river batteries . Underground salt caverns are also seen as a promising storage option for storing hydrogen as an energy source. A team from RWTH Aachen University, Forschungszentrum Jülich and Fraunhofer IEG rolled out how large their storage potential is in EuropeStudy in the specialist magazine "International Journal of Hydrogen Energy" illuminated.

The interdisciplinary team estimates the total energy storage potential in the form of hydrogen in salt caverns on land and at sea to be 84.8 petawatt hours, with 23.2 petawatt hours on land and 61.6 petawatt hours at sea. According to the analysis, Germany has a total of 35.7 petawatt hours, of which 9.4 petawatt hours are on land - the largest national potential on land in Europe. For comparison: the potential for pumped water storage power plants in Europe is around 0.123 petawatt hours.

"Salt caverns are the most promising option for large storage facilities due to the low investment costs, good sealing and low shielding gas requirement," says Peter Kukla, Head of the Georesources Department at Fraunhofer IEG and Professor of Geology at RWTH Aachen University. In order to estimate the economic potential of the salt storage, a more detailed energy system analysis is necessary. This could correlate economic and ecological aspects, energy profiles as well as locations with high energy demand, high energy supply and high storage capacity.