Converting Solar Energy to Hydrogen

Many readers may be surprised to learn that solar power was discovered as far back as 1839 by a scientist named Edmond Becquerel. [1] Since this time, mankind has been refining this renewable source of energy in order to harness its numerous benefits. One of the most potent methods involves converting solar energy to hydrogen.

Although this is a relatively well-established concept, most individuals are unaware of its technical nature. We will delve into several topics throughout this article. Some of these include photovoltaic electrolysis, the role of solar panels, the fundamentals of a solar hydrogen system, and modern energy storage methods. The main goal is to obtain a better understanding of such innovations in order to better appreciate where the industry is headed.

A Basic Look at the Principle of Converting Solar Energy to Hydrogen

So, what does hydrogen production from solar energy actually entail? It is best to begin by briefly describing electrolysis. Electrolysis involves passing a current through a liquid in order to separate its molecular components. In the case of water (H┬▓0), an electric current will cause oxygen and hydrogen to split apart. [2]

Once water has been broken down in such a manner, the hydrogen can be subsequently collected for future uses. Not that many other examples of electrolysis exist. An additional process involves passing a current through molten sodium chloride; producing chlorine gas and metallic sodium (important chemicals within many industries). The main point is that solar hydrogen generators will generally use this approach to achieve photovoltaic hydrogen production. We will examine this concept in more detail a bit later.

What Exactly is Solar Energy?

For a broad perspective, solar energy involves any process that converts energy from the sun into other usable forms such as thermal or electrical power. [3] How is this physically accomplished? Considering that photovoltaic technology has now become commonplace in today's society, this question warrants further attention.

Without becoming overly technical, a series of solar panels will "capture" photons (bundles of light) that are emitted by the sun. These photons are then channelled into an electrical field within the photovoltaic (PV) cell. This ultimately generates a flow of electricity.

The energy is thereafter directed through a series of metallic contacts before passing on to an inverter. Inverters will normally convert direct current (DC) into alternating current (AC); one of the most widely consumed forms of electrical energy throughout India. [4] Note that this is only a basic overview.

Battery storage is the most prevalent and directly related to this article. When energy is sent from a PV panel to a battery, a series of reactions will occur; allowing the battery to store electricity in the form of chemical energy. While lead-acid and lithium-ion batteries are still widely used, green alternatives (such as hydrogen fuel cells) have already begun to attract widespread attention. The team at EFOY will be happy to explain the benefits of our fuel cells.

Thermal energy storage is another option. In this case, mediums such as water or molten salt are used to "trap" the energy from the sun. This causes the solutions to retain a great deal of heat. The heat can thereafter be used to boil water and produce steam; an effective way to mechanically drive turbines and other devices.

What is Hydrogen?

Hydrogen is by far the most common element in existence. In fact, hydrogen accounts for nearly 75 per cent of all matter. [6] Not only is hydrogen an unlimited resource, but hydrogen can be combined with other elements such as oxygen in order to generate energy.

Hydrogen is considered to represent a "green" energy solution., Not only does this arise from its abundance, but from the fact that energy production only releases water vapour and a small amount of heat. Hydrogen is preferred over traditional fossil fuels due to its environmentally friendly nature. However some types of hydrogen are cleaner than others. This depends on how the gas is being produced.

How Can Hydrogen be Efficiently Produced?

For the sake of this article, we will be discussing solar energy and hydrogen production. We have already discussed how PV cells can be used to convert photons into electricity. This is the fundamental principle behind making hydrogen with solar panels. However, some additional steps are required.

Electrolysis is once again involved. As opposed to directing PV-generated electricity into a battery, it is instead routed to a reservoir of water. This will cause the hydrogen and oxygen to separate. [7] It is also interesting to note that some of the most modern solar powered hydrogen generators are now capable of producing hydrogen by tapping into airborne moisture; potentially ushering in an even more economically viable solution.

Yet another innovation comes in the form of what are known as solar hydrogen panels. As opposed to requiring electrolytic conversion, these panels instead use a process called photocatalytic water splitting. This is essentially a closed system that offers on-site hydrogen production. [8] Such alternatives are extremely attractive within off grid hydrogen power systems and similar scenarios that seek to eliminate traditional electrolysis from the equation.

Using solar energy to produce hydrogen will also require viable storage solutions. Fuel cells represent an extremely practical method of hydrogen solar energy storage. Not only are these environmentally friendly solutions, but they offer a reliable source of long-term power.

What Advantages Can Converting Solar Energy to Hydrogen Offer?

We can now see that converting solar energy to hydrogen gas is a relatively straightforward process. This helps to dramatically streamline the implementation process. Also, there are other unique benefits that should never be overlooked. These include [9]:

  • Heat and water vapour are the only byproducts.
  • Hydrogen is the most abundant element on the planet.
  • The relationship between green hydrogen and solar energy is already well understood.
  • Converting to this alternative form of energy can allow fast-growing nations such as India to meet their carbon reduction targets.

We can now begin to see why there are many incentives to embrace the solar energy to hydrogen production model.

What Challenges Might Converting Solar Energy to Hydrogen Pose?

Hydrogen production using solar energy is still an emerging technology. Therefore, a handful of stumbling blocks might need to be overcome. Pertinent examples include consumer awareness, industry-wide adoption, transportation costs, and securing the necessary capital. Furthermore, some have also argued that the future demand for green hydrogen is not guaranteed. [10] Nevertheless, demand for hydrogen has risen sharply to date and is expected to continue to do so.

Another good news is that EFOY already offers a host of hydrogen fuel cells designed for numerous practical applications. We also remain at the forefront of the latest renewable energy solutions; enabling our customers to remain well ahead of the curve. Please contact us to learn more about green hydrogen or our line of products.

The Means of Storing Solar Energy

  • Batteries
  • Thermal storage

Sources:

  • [1] https://en.wikipedia.org/wiki/Timeline_of_solar_cells
  • [2] https://www.sciencedirect.com/topics/engineering/water-electrolysis
  • [3] https://www.energy.gov/eere/solar/articles/pv-cells-101-primer-solar-photovoltaic-cell
  • [4] https://www.seia.org/initiatives/about-solar-energy
  • [5] https://aurorasolar.com/blog/storing-solar-energy-everything-you-need-to-know/
  • [6] https://stardate.org/astro-guide/hydrogen-and-helium
  • [7] https://link.springer.com/chapter/10.1007/978-1-4020-6442-5_12
  • [8] https://en.wikipedia.org/wiki/Solar_hydrogen_panel
  • [9] https://timesofindia.indiatimes.com/readersblog/beyondtheswitch/embracing-hydrogen-a-promising-fuel-for-indias-sustainable-future-55719/
  • [10] https://100re-map.net/green-hydrogen-market-potentials-and-challenges/