In recent decades, the growing dependence of our economy on fossil fuels has aggravated both environmental and economic challenges due to a combination of two factors: the growth in energy demand and the progressive depletion of fossil fuel reserves. This scenario has created significant tensions in the energy supply chain, highlighting the urgent need to find sustainable alternatives. As a response, recent R&D&I efforts have increasingly focused on the decarbonisation.

However, for decarbonisation to be truly efficient, it is necessary to understand that the new energy system must be made up of a combination of technologies both being capable of satisfying the growing energy demand and being sustainable. Hydrogen enters the picture as a key energy vector – both at industrial and domestic level – with potential to transform the global energy landscape.

Hydrogen: the energy wildcard of the future

One of the features that make hydrogen a great alternative is that it can be produced by renewable energies through electrolysis. This technology makes it possible to convert the energy surpluses produced during peaks of renewable generation – when there is an abundance of sun or wind – into hydrogen, a clean energy and versatile energy carrier. Moreover, hydrogen can be stored for long periods and then be converted both into electricity – using fuel cells or generators – or into heat, using boilers.

In addition to its storage capacity, hydrogen also offers flexibility in terms of transport. It can be distributed through a pipeline network similar to that used for natural gas, although local or decentralised production is also feasible, which significantly reduces transport costs. Such decentralisation would enhance the sustainability and self-sufficiency of the developed electricity system, increasing storage capacity and providing greater flexibility and availability of clean energy.

Hydrogen also plays a key role in the current and future chemical industry, being a valuable resource in processes such as the production of gasoline and other petroleum derivatives. In the future, it will be fundamental in the creation of synthetic fuels from CO2, which will contribute significantly to reducing the carbon footprint of these fuels.

These include alkaline electrolysis, one of the oldest technologies; proton exchange membrane electrolysis (PEM) – whose development has accelerated in the last decade – and solid oxide electrolysis (SOEC) – which is under development and is prominent in industries with surplus heat.

The true colours of H2

The path towards decarbonisation cannot afford to get rid of fossil fuels immediately. It requires a planned and gradual approach that considers environmental impact. While hydrogen production through renewable energy is the most sustainable and preferred option in the long term, other technologies still play an important role in this process. These technologies, which allow hydrogen to be produced from different sources, have led to the classification of hydrogen into different ‘colours’, depending on the raw materials used and the production methods applied.

• • Golden hydrogen refers to hydrogen that existed already on Earth, in underground deposits, and does not require industrial processes to obtain it.
  • Brown hydrogen comes from coal gasification, a process with high carbon emissions.
  • Grey hydrogen, produced from natural gas, also emits large amounts of CO2 during its production. It’s currently one of the most common.
  • Blue hydrogen is produced in a similar way to grey hydrogen, but includes carbon capture and storage systems (CCS), which significantly reduces pollutant emissions.
  • Pink hydrogen is produced using nuclear-generated electricity, which, although low in emissions, raises debate over nuclear waste.
  • Yellow hydrogen refers to hydrogen produced using electricity from an energy mix that can include both renewable and non-renewable sources, which generates a medium environmental impact.
  • Green hydrogen, considered the most sustainable, is generated from renewable energy sources, such as solar or wind power, ensuring a zero-carbon production process.

By establishing these categories, a better understanding of the environmental footprint and the advantages or disadvantages of each type of hydrogen is facilitated, which is crucial for the design of energy policies and for guiding investment decisions towards cleaner technologies.

The technological evolution behind green hydrogen

The growth of renewable energy has driven the development of water electrolysis as one of the main technologies for producing green hydrogen. This process uses clean energy – such as solar or wind power – to split the water molecule into hydrogen and oxygen. Currently, there are three commercial electrolysis technologies operating and another one in development:

• • • Alkaline electrolysis. It uses a basic medium and operates at temperatures close to 80ºC and at atmospheric pressure (1.01325 bar), although it is possible to work with up to 30 bar. Low current densities are used, which implies a lower production per occupied surface area, but high efficiencies are achieved, close to 70%. Abundant materials such as steel or nickel can be used for their construction.

• • • PEM (polymeric proton membrane) electrolysis. It uses an acid medium and operates at temperatures close to 60ºC and pressures above 30 bar. High current densities are used, allowing for very compact equipment, but the efficiency is slightly lower. Rare metals are used in their construction, which makes the equipment more expensive.
    • SOEC (solid oxide electrolysis cell). It is a solid electrolyte which uses water at very high temperatures – around 800ºC – and atmospheric pressure. The current density used is somewhat lower than that used in PEM electrolysers, resulting in compact equipment and efficiencies of up to 80%. They require an external supply of energy in the form of heat though. The materials used are more expensive because they must withstand the high temperatures.
    • AEM (anion exchange membrane) electrolysis. It combines the best of PEM & Alkaline technologies obtaining high current densities and an average efficiency between the two variants. However, current equipment is not yet at the level of development needed to be competitive. While the necessary materials are abundant, the problem lies in the membrane, for which a suitable material has not yet been developed.

Pioneers in hydrogen: genesal energy bets for the change

Genesal Energy is actually committed to hydrogen. We are developing our own electrolyser with the aim of acquiring experience in this technology. It’s called the H2OG project. In the medium term, this knowledge will allow us to optimally integrate this energy vector in our machinery, not only in the generator sets, but also in the management and storage systems.
The development of this project began with the design of a small-scale electrolyser, which allows us to validate its operation and guarantee the expected results. This planning is key before building the final, larger equipment, as it allows solving possible design flaws before the final integration into the production system, which translates into lower costs.
If you want to know more about the project, watch the following video, in which Guillermo Martínez, Chemical Engineer, explains more about the subject.

The USC-Genesal Energy Chair of Energy Transition organised the IV Seminar on Corporate Carbon Footprint for SMEs, a meeting that brought together technicians and professionals from small and medium enterprises committed to sustainability.

The aim of the event was building intelligence on the carbon footprint as a KPI used to improve the sustainability strategies. The seminar was attended by experts who shared their experience on its measurement and reduction and the integration of sustainability in the business strategy. The speakers were PhD Enrique Roca Bordello, director of the Chair, and PhD Eugenio Fernández Carrasco – both researchers from the Department of Chemical Engineering of the USC-, Genesal Energy’s CEO & CFO, Julio Arca, and the Sustainability Coordinator at Genesal Energy, Antía Míguez Fariña.

During the first part of the conference, Mr. Roca and Mr. Fernández focused their interventions on the keys to identify the different parameters of the carbon footprint, the most used methodologies and how to measure it. In addition, they presented various practical tools which allow organisations to monitor their emissions improving sustainability indicators in their operations.

Genesal’s experience with corporate carbon footprint

Following, Mr. Arca and Ms. Míguez commented on their experience as a sustainable and socially committed company. They explained the guidelines that a company should include in its Environmental Social Governance strategy to become a benchmark in the implementation of sustainability policies. They also analysed the Border Carbon Adjustment Mechanism, a reference instrument to put a fair price on carbon emitted during the production of carbon-intensive goods entering the EU and to encourage cleaner industrial production in non-EU countries.

Mr. Arca, one of the promoters of the initiative, pointed out that ‘these meetings are essential to create a space for the exchange of knowledge between researchers and business, leading to greater awareness, greater knowledge and an increase in the number of companies that will implement sustainability policies’.

A successful event that, given the interest it arouses, will continue to be held annually.

Hydrogenated vegetable oil is making its way into the market due to its numerous properties and is one of the paths towards the energy transition.

Electricity is by no means the main form of energy used, nor is it easy to bring electrification to all sectors, and although it is true that the advance of renewable sources is remarkable, these days 80% of the world’s primary energy demand is still based on fossil fuels. An issue, not only because of the high levels of emissions and their consequences on climate change, but also because of the finite nature of these fuels.

Genesal Energy is very aware that it is urgent to find new sustainable fuels for those sectors where electrification is not going to happen overnight. HVO enters the scene, which in recent years has been positioning itself as one of the main alternatives to diesel. We give you all the keys to this new fuel.

What is HVO?

Hydrogenated Vegetable Oil (HVO) is a second-generation biofuel. Although it has the words “vegetable oil” in its name, it can be produced from a variety of vegetable and non-vegetable sources:

• Used vegetable cooking oil (UCO, Used Cooking Oil).
• Waste animal fat.
• Tall oil, a by-product of wood pulp manufacture.
• Non-food grade vegetable oils (rapeseed, soybean and palm).

On their own, these oils are not effective fuels. However, through a process known as hydrotreating, it is possible to convert the fats in these oils into hydrocarbons almost identical to conventional diesel.

Is it the same as biodiesel?

No, biodiesel and HVO are different fuels. While both are based on triglycerides from vegetable oils and animal fats, biodiesel is made by esterification: the oily source is treated with an alcohol, usually methanol, and a catalyst. This produces glycerine and a fuel made from fatty acid methyl esters or FAME (Fatty Acid Methyl Ester).

On the other hand, to obtain HVO, the oils are subjected to a hydrotreating process. Simply put, hydrogen is used to remove oxygen from the oil at high temperatures, splitting the fat molecules into separate chains of hydrocarbon molecules. The result is a stable fuel comparable to fossil diesel in both form and performance, making HVO superior to biodiesel as an alternative to fossil fuel.

What are the advantages of using HVO?

They include the following:

• -If waste oils are used as source, and produced relatively locally, the use of HVO can result in a reduction of CO2e emissions by up to 90%.
• When burning HVO, emissions of carbon monoxide (COx) and other polluting particles are lower.
• Its service life is long: up to ten times longer than diesel.
• Its performance is maintained even at extreme temperatures (-30°C).
• It has good chemical characteristics. It is aromatic, low density, with a very high cetane number and no sulphur. In addition, its calorific value, and therefore its energy content, is higher than that of biodiesel.
• Unlike biodiesel, which needs to be blended with conventional diesel to work properly, HVO is a direct fuel, which can be completely replaced in most diesel units.
• Also in comparison, biodiesel is prone to degradation and needs very specific planning for storage. Only a single oil tank is needed to store HVO. In fact, conventional diesel tanks can be filled with HVO, and vice versa, so that if, for example, we are running on HVO, but it runs out and it is impossible to procure it quickly enough, we can switch back to diesel.

Different brands in the combustion engines and distributed energy worlds have already started to echo the benefits of HVO, certifying that their products are compatible with this biofuel.

For example, several companies have declared that all their Euro 5 and Euro 6 engines are compatible with the use of HVO.

Is HVO sustainable?

Speaking of sustainability we must pay attention not only to its properties, but also to its entire value chain. Are the source and production relatively local? Regarding the origin of the source, are only waste oils used, or do they also include, for example, oil crops? Have changes in land use been necessary to make such crops available? If we look at the whole picture, to speak of a 100% HVO we need to be sure that it is produced from a source derived from real waste and that environmental and social criteria are respected along the whole value chain.

And another question arises: If we have available an HVO that we know is not 100% sustainable… Is it better to use it or to continue using fossil diesel? Do we look for an alternative, such as another type of biofuel or even a synthetic fuel? These are difficult questions to answer that depend on many factors.

The Greenesal Scale

In order to facilitate decision making on the choice and use of fuels, Genesal Energy has created the “Greenesal Sustainability Assessment Scale for Fuels”.

It is a tool that will allow us to evaluate the sustainability of fuels, so that it is not only easier to choose between the different options available, but it will also provide a clear idea of the real impact of each one of them.  In addition, the tool will fairly weight factors related to the three spheres of the sustainable development:

• Environmental sphere: raw material origin, GHG emissions, soil organic carbon, eutrophication, acidification, energy balance, biodiversity.
• Economic sphere: capital costs, operational costs.
• Social sphere: land rights, issues related to working conditions, relationship with local communities.

In this way, not only will it be possible to distinguish between different types of fuel, but it will also be possible to know which has a greater positive impact on the search for a sustainable future.