The importance of the design tools and green hydrogen optimisation
Green hydrogen is positioning itself as a viable alternative in the context of the transition towards clean and sustainable energy sources. Not only does this energy carrier transform energy without emitting pollutants, but it also has significant long-term storage capacity, which helps to address one of the main problems of renewable energy sources such as solar and wind: their intermittent and seasonal nature.
Due to the several hydrogen applications and the variable nature of renewable sources, the design and optimisation of green hydrogen production, storage and utilisation systems are complex processes especially when applyied to industrial processes, where careful management of the entire chain is necessary to ensure continuous and efficient operation. This is where simulation and optimisation tools plays a crucial role, facilitating the efficient integration of hydrogen into the energy system and enabling optimal decisions to be made based on detailed data and accurate projections.
Need for specialised tools for energy transition
In order to move towards a more sustainable and decarbonised energy system, it is essential to apply dynamic modelling and simulation to optimise both the production and use of green hydrogen in the residential, industrial and heavy transport sectors, as each has different energy demand patterns, requiring the development of specific tools to evaluate multiple scenarios, optimise design and determine the most appropriate control and management strategies.
These tools not only allow the simulation of system behaviour under real conditions, but also help to optimise important parameters such as electrolyser power ratings, hydrogen storage volume and the management of optimal times to consume or storage energy. The application of advanced optimisation algorithms aims to reduce operational and investment costs while maximising the use of renewable energy by ensuring that the best technical, economical and ecological decisions are made.
Functionalities of the developed tool
CARTIF which is a Cervera Centre of Excellence, awarded by the Ministry of Science and Innovation and the CDTI, under the files CER-20191019 and CER-20211002 has developed a tool for the design and optimisation of this type of systems thanks to the CERVERA H24NewAgeproject. It is a platform that enables the design and optimisation of systems for the production and use of green hydrogen in residential and industrial environments by applying dynamic modelling together with Python through an easy-to-use web interface that facilitates access to complex simulations without the need for advanced technical knowledge, contributing to the democratisation of hydrogen technology, allowing users with different levels of experience to interact with complex models and gather useful information for decision-making in the design of their systems. Some of the key points of the tool are:
Simulation of hydrogen production scenarios: Users can simulate a variety of hydrogen production environments, such as industrial processes, industrial cogeneration, residential micro-cogeneration and large-scale power generation.
Optimisation Based on Advance Algorithms: The tool helps to size the optimal size of system components, minimising costs and maximising renewable energy utilisation using advanced optimisation algorithms. It also includes the creation of operational strategies that consider renewable energy availability, hydrogen demand and storage constraints to achieve economical and efficient operation.
Flexibility and Adaptability: Crucial parameters such as geographic location, demand profiles and renewable production technologies can be adjusted through the platform, making it ideal for a variety of scenarios and specific needs. This capability is fundamental for users to assess how their designs would perform in different situations and scenarios, adapting hydrogen production and storage technologies to the particularities of each environment.
Visualization of results: The tool’s web interface makes it easy to visualise simulation results through interactive graphs and tables showing key aspects of the system, such as energy efficiency, operating costs and storage capacity. Users can also compare the results of different scenarios, which is essential for identifying opportunities for improvement and making further adjustments.
Conclusions
Ultimately, tools such as these can be used to evaluate and optimise strategies for the production and use of green hydrogen, facilitating its integration into the energy system and contributing to a more sustainable future. Thanks to access to advanced models and optimisation algorithms, these tools enable informed decisions to be made, resulting in more efficient and resilient systems. A clear example would be the optimal hydrogen storage capacity, the correct estimation of which can avoid unnecessary costs and ensure a constant supply, increasing the operational efficiency of the system. In addition, the ease of use and flexibility offered by these platforms help reduce the technical barriers to adopting green hydrogen, making it an accessible and viable option for a wider range of users and applications. This is key to moving towards an effective energy transition and to fostering solutions that reduce dependence on fossil fuels and support climate change mitigation.
Co-authors
Jesús Samaniego. Industrial Engineer. Since 2002 he has been working at CARTIF in the development of projects within the field of energy efficiency, the integration of renewable energies and in the study of the quality of the electricity supply
I have always been passionate about telecommunications, and the implicit idea of achieving a “connected world”, wired or wireless, where information flows from one end of the globe to the other, regardless of the location and the native way in which each country, city or region tends to communicate. But in the face of this idealisation of a historically and recurrently connected world, there are problems of understanding in this communication. Whether it is because the language is different, because different alphabets or writing is used, or because culturally the rules of language use and the way of communicating differ from continent to continent, the reality is that global communication is a challenge that we continue to face today.
In the era of digitisation and the Internet of Things (IoT), where large volumes of data are now being collected, stored and processed, problems in the communication and unique representation of information are once again becoming apparent. It will be difficult to find data capture devices (from different manufacturers) that provide information using the same format, or that answer using the same question. Such is the problem that there are disciplines, including telematics, that focus on defining and specifying standard communication protocols that apply to different domains. But what if we want to communicate different domains? Despite the existence of standards, the problem persists. We are faced with a Digital Tower of Babel, where the heterogeinity of protocols, representation formats, communication rules and standards once again makes understanding between systems and solutions difficult.
To solve this problem, and of course, in the military and technological sphere, the concept of interoperability was born, understood as the ability of the armed forces of different nations to collaborate efficiently through the integration of systems and communications. This interoperability approach was later adopted by other sectors, such as the Information and Communications Technology (ICT) sector, with the development of systems that required efficient and conflict-free information sharing between different devices and platforms. In this ICT context, interoperability is understood as the ability of different systems, devices or applications to comunicate, exchange and use information effectively and coherently.
“Interoperability. Understood as the ability of different systems, devices or applications to comunicate, exchange and use information effectively and coherently.”
To achieve this interoperability between heterogeneous systems, i.e., systems that speak different languages and represent the information in different ways, we need to cover several dimensions, each focusing on a different aspect of communication and data exchange between systems:
Technical interoperability refers to the ability of different systems and devices to connect and communicate with each other through standards and protocols. This includes hardware, software, networking and communications compatibility.
Semantic interoperability is responsible for ensuring that the information exchanged is understood in the same way by all parties, thanks to the generation of a common vocabulary (ontology). It is about ensuring that systems interpret data with the same meaning, regardless of how they are structured or labelled.
Syntactic interoperability ensures that systems can process and exchange data in a structured way, i.e., that the same data formats and structures, such as XML or JSON, are used.
Organisational interoperability involves the alignment of policies, processes and regulations across organisations to enable effective collaboration. It encompases governance arrangements, security policies and data management.
One of the sectors that will benefit greatly from these interoperability solutions is the building sector, where digitisation and information exchange at all stages of the life cycle offers a springboard for development and competitiveness. Here, the creation of intelligent buildings, highly monitoring and able to anticipate the needs of their users thanks to digitisation and advanced data processing, alowws forbuildings that contribute to the goals of efficiency, decarbonisation and sustainability. In this context, interoperability solutions allows the diverse energy systems (such as lighting,HVAC, air conditioning, etc.) to work together, sharing and processing data seamlessly, regardless of manufacturers or platforms. This helps to optimise building management, reduce costs and improve energy efficiency by enabling systems to work as an integrated ecosystem.
At CARTIF we have been working for more than a decade on energy efficiency projects where interoperability enabling technologies, both technical and semantic, are a key element for obtaining smart, open and highly replicable solutions. Projects such as DigiBuild, DEDALUS and BuildON are examples of how these technologies facilitate the creation of smart and sustainable buildings.
Do you want to know the tool before telling you more about it? Enter to the Beta version here
In 2022, the European Commission choosed 112 cities to participate in the”100 Climate-Neutral and Smart Cities by 2030″ initiative (27 european and 12 from partner countries). These cities would receive technical support from the Mission Cities platform run by the European NetZeroCities project, with the objective of acting as centres of experimentation and innovation to reach climate neutrality by 2030; as well as serving as model for other cities to reach the same goal by 2050.
Since the start of the project, NetZeroCities has supported the 112 cities selected as “Mission Cities”, which have participated in programmes such as the “Pilot Cities Programme” and the “Twinning Learning Programme”.
To formalise this sustainability objective, NetZeroCities project has supported the development of Climate City Contracts in the selected cities. These formalise an agreement between the city, its stakeholders (such as companies, civil organisations and citizens) and the European Commission; setting out clear and specific commitments for 2030 and 2050.
NetZeroCities context
Climate City Contract: a contract through climate neutrality
Climate City Contract (CCC) is an action plan that allows the municipality to define the actions and the public and private municipal actors involved in the development of actions aimed at achieving climate neutrality by 2030 and 2050. This process is iterative and allows for new commitments and periodic evaluation of the measures taken.
Climate City Contract Sections
This document establishes a comprehensive strategy divided into three main lines of intervention, the agreement of the parties called commitments, the strategy for climate neutrality called Action plan and the economic model that supports it, called Investmen plan.
To do, cities must formalise a common commitment among all stakeholders, identifying priority sectors, principles of climate justice and collaboration, and actors committed to the city´s climate goals. It then presents an action plan that assesses the strengths and gaps of existing policies, proposing a portfolio of coordinated interventions that includes an emissions inventory as a starting point and highlights the social benefits of the proposed actions, as well as providing conclusions for future updates of the plan. In this section, Solution Bundles play a crucial role in offering direct solutions to move towards climate neutrality and facilitate the necessary commitments and processes to achieve it in each city together with the stakeholders invovled. Finally, an investment plan is developed that organises public and private resources, analyses past and current investments, identifies barriers and needs, and develops policies to attract capital, mitigate financial risks and build capacity with the active participation of key stakeholders.
The tool: Solution Bundles
Concept and Description
From CARTIF, the team compound by Rosalía Simón, Ana Belén Gómez , Andrea Gabaldón, Carolina Pastor y Carla Rodríguez, has developed this tool to support cities in the development of their Climate City Contract. Solution Bundles provide combinations of enabling technologies and mechanisms that when implemented together maximise their impact, facilitating the selection of actions aimed at achieving climate neutrality. The aim is to facilitate the visualisation of a comprehensive and effective approach, improving acces to the NetZeroCities Information Repository and the understanding of innovative urban solutions.
In addition, Solution Bundles can be used as a canvas in the work of engaging local stakeholders to increase their participation; they act as an interactive canvas for workshops, facilitating the creation of resources or knowledge between municipalities and other stakeholders.
The tool has four packages, which allow the selection of diverse technologies through interactive and simple diagrams; as well as presenting this information in relation to the scale of implementation (City, District and Building).
“E-Movility and electrification”: The included solutions on this package are focus on the production of renewable energy and the decarbonization of all sectors through electrification.
“Low-carbon energy via setor coupling”: This package focuses on connecting different sectors through energy systems, applying principles of circular economy and waste reuse.
“Reduction of energy & resources needs”: This package hosts passive solutions focused on reducing energy needs in the built environment, increasing the efficiency of resource and energy utilisation systems.
”Carbon capture, storage & removal”: This package focuses on reducing energy needs through carbon sinks, eliminating residual emissions and using Nature Based Solutions (NBS) to manage the city’s ecosystems and optimise carbon sequestration.
Development of the tool and implementation on the portal
Its development is being carried out in different phases, with the aim of implementing feedback from different users and cities. Initially, it will be focused on helping Mission Cities, but with the aim of supporting all cities in their process towards climate neutrality by 2050.
Currently, the tool is still under development and only two of the four packages are active; they are available on the project’s portal as beta version for Mission Cities.
How to use it?
Choose your approach: Beggin selecting the package you want to focus on: “E-Movility and electrification”, “Low-carbon energy via setor coupling”, “Reduction of energy & resources needs” y ”Carbon capture, storage & removal”.
Filtering options:You can then customise your view by checking or unchecking boxes to show or hide specific areas of the package. This feature helps you focus on the solutions most relevant to your objective, reducing the number of actions presented and making the process more efficient.
Explore solutions: The solutions shown are linked to factsheets in the NetZeroCities Information Repository, related scientific articles and case studies, covering various thematic areas. If you want more information about the technical solutions, you can access to the following link.
Connection to Enabling Mechanisms: At the top of the tool, you will find connections to other resources (Finance, Policy and Governance, and Capacity) for the selected package. These new resources provide information on how to improve the strategic framework where solutions are implemented.
The world is moving towards a future without fossil fuels, and this transformation is already underway. Fossil fuels, which have been the main source of energy for more than a century, are in decline for reasons of both environmental sustainability and limited availability1.
The PNIEC (National Integrated Energy and Climate Plan 2021-2030) stipulates that by 2030, 42% of the final energy consumed must come from renewable sources. To reach this objective, 27% of this final energy must be electricity, mostly generated from renewable sources (with a goal of 74%). This will involve the installation of more than 55GW of additional renewable generation capacity. This increase in the share of renewables in our energy mix raises new technical issues, as renewables, by their nature, are intermittent and less predictable compared to traditional energy sources. This can lead to inestabilities in the electricity grid, manifesting themselves as congestion and voltage variations.
On the demand side, the energy transition will also require an increase in the electrification of energy consumption, especially in the transport and air conditioning sectors, as well as in some industrial demands.
For the electric system, this will result in an increase in electricity demand and a transition from a traditional, flexible and highly predictable centralised generation system, with passive consumers and distribution networks, to predominantly renewable, decentralised and intermittent generation system, with managable demand resources and an increasing need for flexibility to ensure efficient levels of quality and safety..
The flexibility of a power system is defined by its ability to adapt to imbalances between generated and consumed power. Failure to meet this condition can lead to system and, therefore, on the supply. Till today, the flexibility of our system has being mainly proportionated by fossil generation plants, that equilibrates the generation of existent demand, maintaining a controlled growth of the electric demand. However, at the energy transition context, this change for several reasons:
The flexibility of a power system is defined by its ability to adapt to imbalances between generated and consumed power
The main renewable generation sources (solar and wind) do not have the capacity to “keep up” with demand.
When the transmission capacity of power lines is exceeded by demand, congestion arises, leading to overloads and supply failures.
When the quantity of power generated doesn´t match the real-time demand, voltage variations occur, affecting the quality of the power supply and potentially damaging equipment and appliances connected to the grid.
The electrification process entails a significant increase in consumption on transmission and distribution lines, which must be adapted to this increase in demand, especially during consumption peaks. Adapting these infrastructures exclusively through the repowering of lines or the installation of additional lines would have a very high material and economi cost.
The current model of renewable energy integration is associated with more decentralised generation, wich means that flexibility suppliers will also be increasingly distributed across distribution networks.
Although electricity storage offers high system flexibility, its high cost, especially in pre-metered systems, makes it necessary to consider additional sources of demand flexibility.
For all of these reasons, it is considered critical to favour and promote demand flexibility. This can be done implicitly, through incentives for users to change their consumption habits, for example, price signals, and also explicitly, where the activation of flexibility is direct and with a shorter-term response. An example of this second case is balancing services.
On the other hand, grid instability, resulting from the high share of renewables in a decentralised scheme, can be addressed through participation in local flexibility markets, which allow consumers and small generators to offer consumption and generation adjustment services, helping to stabilise the grid.
In the ENFLATE project, CARTIF is developing a flexibility management tool that helps the network operator to manage distribution networks by simulating scenarios representing participation in local flexibility markets. In is also possible to simulate the provision of balancing services for the transmission grid operator. These services are studied on the electricity netowrk of Láchar (Granada), operated by the partner CUERVA.
In Spain there is still no regulatory framework for local flexibility markets, so the European framework is used. The minimum size of flexibility offered in the local flexibility markets considered in the ENFLATE project is of 0.1MWh and the trading period is one hour. The two products offered are: surge management and congestion management.
Balancing services are offered in the balancing markets. There are three possible services: primary regulation, secondary regulation and tertiary regulation. In ENFLATE we simulate the last one, also known as manual actuation reserve for frequency. It allows offering 1MW to be bid and the trading period is from 15 minutes to two hours.
ADAION is another partner providing digitisation services on the demonstrator. Its cloud-based platform uses artificial intelligence to simulate and know the capacity of the network at all times. It provides the necessary inputs to the algorithm developed by CARTIF, so that participation in both markets can be simulated. Renewable generation, flexible demand and electric storage.
Thanks to projects such as ENFLATE, we can study the scope and benefits of using demand flexibility in real demonstrators such as the Láchar grid, simulating flexibility and balancing market conditions. In this way, we prepare for the challenges of the energy transition. At national level, the current regulatory framework for demand-side flexibility is underdeveloped and scatteres in various regulations, which have gradually been modified with the aim of transposing the European Directives. While they are being consolidated, we preparing for change with projects financed by the European Commission, as in the case of ENFLATE2.
In the vast universe of energy technology, lithium-ion batteries have reignes supreme for decades. From our mobile phones to electric vehicles, these batteries have been the silent engine that drives our daily lives. But, like any technology, lithium also has its limitations and challenges. What comes next? Join us as we explore the batteries of the future and the alternatives to lithium that could transform the world.
Why look for alternatives to lithium?
Lithium has numerous advantages, but it also presents significant challenges. Lithium can be environmentally costly to extract, and growing demand is putting pressure on global supplies. In addition, lithium batteries, while efficient, have limitations in terms of storage capacity and safety. So what options do we have?
Battery breakthroughs: overcoming challenges for a sustainable energy future
In the search for more affordable and abundant alternatives to lithium-ion batteries, sodium-ion batteries are emerging as a promising option by using sodium instead of lithium as the active ion. Although they do not currently achieve the same energy density as lithium batteries, sodium-ion batteries offer significant advantages in safety and sustainability by using more abundant and less expensive materials. In addition, solid-state batteries represent another innovation by replacing liquid electrolyte with solid electrolyte, improving safety and potentially energy efficiency with higher energy densities and faster charge times, making them ideal for applications in electric vehicles and portable devices. Finally, graphene, known for its ultra-thin and tough structure, is revolutionising energy storage with promises of ultra-fast charge times and long lifetimes, promoting significant advances in consumer electronics and industries, and paving the way for a new generation of more efficient and durable devices.
Beyond batteries: exploring new frontiers in energy storage
While electric batteries have been the mainstay of modern energy storage, relying only on one technology isn´t enough to meet the energy challenges of the future. Diversification of storage sources is essential to create a robust and resilient energy system. In addition to electric batteries, exploring options such as thermal storage and other innovative methods will allow us to make better use of renewable energy, optimise energy efficiency and ensure a constant and reliable supply.
Let´s discover some of these fascinanting alternatives!
Can abundant natural resources be harnessed for energy storage? Air and water prove it!
Compressed air storage (CAES) uses underground caverns or tanks to compress air at high pressure during periods of low electric demand. When electricity is required, the compressed air is expanded to generate power efficiently through turbines, which is crucial for stabilising power grids in areas where topography doesn´t allow for reservoirs. Hidraulic storage, on the other hand, harnesses reservoirs and dams to store and release water on demand, providing stability to the electricity system and facilitating the integration of intermitent renewable enrgies towards a more sustainable and stable future.
Energy revolution: how we cover the peaks of demand with advance technology
In the vibrant world of energy, one of the biggest challenges is managing those times when energy consumption spikes unexpectedly. How do we ensure that our power grid holds up without blackouts?
An alternative can be flywheels, which are notable for their ability to store kinetic energy in a rotating disc and release it almost instantly. But they aren´t the only heroes in this scneario. Supercapacitors, with their ability to charge and discharge energy at breakneck speeds, also play a crucial role in providing a boost of energy when it is needed most.
By integrating these technologies, which are capable of providing large power peaks in short periods of time, with other storage or generation systems, remarkable stability is achieved in electricity grids. This is especially beneficial for small or medium-sized grids that intend to operate in isolation, ensuring a reliable and constant power supply.
Phase change materials (PCM): heat under control and thermal change materials (TCM): efficient storage
Phase change materials (PCM) are substances that store and release large amounts of thermal energy during their melting and solidification process. These materials can be used for applications such as building air conditioning, improving energy efficiency and reducing the need for heating and cooling systems.
Similar to PCM, thermal change material (TCM) store thermal energy, but with different mechanisms, such as absorbing and realeasing heat through chemical reactions. The TCM can be used in thermal energy storage systems for solar power plants, increasing efficiency and storage capacity.
Storage and transport: ammonia and hydrogen. Integrated solutions
Ammonia is emerging as a promising energy carrier. It can be used as fuel directly or as a storage medium for hydrogen. As a liquid at moderate temperature and pressure, it is easier to store and transport than pure hydrogen. Moreover, it can be produced sustainably using renewable energies.
Hydrogen is considered by many to be the fuel of the future. It can be produced from water using renewable energy, stored and then converted back into electricity using fuel cells. In addition, it has thermal and mobility apllications. However, the challenge remains the infrastructure for its efficient and safe production, storage and distribution.
The future of batteries and energy storage is brilliant
The race for the next generation of energy storage technologies is in full swing. With so many promising options on the horizon, the future of portable energy and storage looks brighter than ever. From sodium and graphene to innovative phase-change materials and hydrogen, we are on the verge of an energy revolution.
At CARTIF, we excel with innovative projects that explore advanced solutions for energy storage, such as THUMBS UPand SINNOGENES, among others. These projects reflect our strong commitment to research and development of sustainable technologies that are set to transform the global energy landscape. Keep up to date with the latest news by visiting our blog and website to follow these exciting developments.
The hydropower sector is a key driver of the energy transition in Europe. In 2022, renewable energies accounted for 41.2% of the total electricity consumption in Europe, with hydropower representing 29.9% of total renewable generation.
As more energy sources are integrated into the European energy landscape, hydropower plays an essential role due to its flexibility. While the generation from other renewable sources like solar or wind is subject to uncontrollable variable weather conditions, it is possible to decide when to turbine the water from a reservoir or river to generate energy. This way, the hydropower sector helps maintain stability in the electrical grid by balancing demand and generation.
In addition to its fundamental contribution to reducing CO2 emissions, this type of energy offers other environmental and socio-economic benefits. It regulates river flows through its dams, acting against flood threats and providing water supply for human consumption and the agricultural sector. Moreover, it can affect the development of local economies by generating employment, retaining human capital, and creating tourist attractions.
Emerging as a fundamental solution in Europe’s energy transition, hydropower is not without challenges and risks: One of the major challenges in Europe is the high age of infrastructures (an average of 45 years compared to 30 years in regions like Asia-Pacific or 15 years in China1), causing inefficiencies in energy production, increased maintenance stoppages, and production costs due to the need for investment and repair.
Additionally, climatic events are making their effects felt in all regions of the world. In Europe, many areas are experiencing more frequent, intense, and prolonged droughts. In the second half of 2022, this situation became evident with a significant reduction in hydropower production, particularly noticeable in the south of the continent, where a near 15% decrease in production was recorded.
This situation necessitates addressing intelligent management of water and hydropower resources. The iAMP-Hydro project (intelligent Asset Management Platform for Hydropower), coordinated by Trinity College Dublin and involving CARTIF, emerges as an innovative response to the challenges facing the European hydropower sector.
Within the framework of the project, a package of digital solutions based on artificial intelligence will be developed, validated in five hydropower plants distributed between Spain and Greece. These solutions will assist plant operators in decision-making by considering environmental and socio-economic factors.
The project includes a predictive maintenance solution through the development of advanced sensors capable of real-time monitoring of the state of turbines and installations. These devices will collect data which, through deep learning-based AI algorithms, will predict possible malfunctions before they occur. This will not only significantly reduce maintenance costs by up to 10% but also enable optimal scheduling of planned shutdowns adjusted to market conditions and socio-economic needs.
Furthermore, a set of specialized sensors will monitor various biodiversity parameters, ensuring that plant operations have the minimum possible environmental impact.
Lastly, CARTIF is leading the use of artificial intelligence techniques and neural networks to create predictive flow models. These models are designed to analyze patterns in historical data, including climate, and will be able to anticipate the potential energy a hydropower plant can generate over the next 7 days. This anticipation will allow for up to 23% more efficient plant operation, ensuring water availability while minimizing waste. In extreme drought situations like those in southern Europe, predictive models are being implemented to assess the short- and medium-term recovery capacity of hydroelectric reserves, considering various climate scenarios and irrigation demands. These models will provide operators with a clear vision of the plant’s evolution in the medium term and allow them to optimize the selection of the most suitable turbines for each operational scenario.
Researchers predict that iAMP-Hydro will improve the environmental and socio-economic sustainability of the current hydropower fleet by reducing operating costs by €1000 million, cutting CO2 emissions by 1,260 tons, creating 10,000 future jobs, and enabling environmentally sustainable flow regulation through digital solutions.
Current estimates show that digitizing the existing 1,225 GW of hydropower worldwide could increase annual production by 42 TWh, equivalent to $5000 million in annual operating savings2.
1IEA. Hydropower Special Market Report; International Energy Agency: Paris, France, 2021; p. 126
2Kougias, Ioannis & Aggidis, George & Avellan, François & Deniz, Sabri & Lundin, Urban & Moro, Alberto & Muntean, Sebastian & Novara, Daniele & Pérez-Díaz, Juan & Quaranta, Emanuele & Schild, Philippe & Theodossiou, Nicolaos. (2019). Analysis of emerging technologies in the hydropower sector. Renewable and Sustainable Energy Reviews. 113. 10.1016/j.rser.2019.109257