The Next Step Towards a Hydrogen Economy

Modern Motivations for Moving to Water Electrolyzers Global Regulations and Businesses Push for Cleaner Energy

A growing number of international and regional as a transport fuel, natural gas for heating, and regulations now mandate reductions in fossil fuels for generating electricity needed to greenhouse gas emissions. Thus, hydrogen has meet energy requirements of homes, offices, become a serious marketplace contender as a and factories. low-carbon energy source. By 2030, the Hydrogen Council members CEOs from 39 international energy, believe that approximately 230-250 TWh transportation, and industrial companies of surplus solar and wind energy could be formed the Hydrogen Council.¹ This council converted to hydrogen. envisions using hydrogen to replace gasoline

¹Source: http://hydrogencouncil.com/

The Next Step Towards a Hydrogen Economy 2 Increasing Demand for Clean and Scalable Hydrogen Production

Whether hydrogen is burned to produce heat Electricity from renewable sources can also be or converted to electricity in a fuel cell, its only used to produce hydrogen, which represents a by-product is water—making it an attractive win-win for clean energy because: source for clean energy. In fact, the hydrogen • Using hydrogen with renewable wind and generation market is predicted to grow at a solar electricity generation helps meet emis- compound annual growth rate (CAGR) of 5.8% sion regulations through 2025.² This estimate may be conser- vative based on the market’s increased focus • Excess hydrogen can be stored and convert- on cleaner energy, favorable government reg- ed to clean energy via fuel cells when renew- ulations, and other landscape-shifting trends ables don’t produce enough electricity flow driving expansion. Additionally, the growing market for fuel cell However, traditional methods of hydrogen cars (electric vehicles powered by hydrogen) will production via steam or oil reforming and coal continue to boom, further increasing the demand gasification result in significant greenhouse for clean energy production.³ gas emissions. Stringent regulations designed to control the use of these fossil fuels will likely influence the market to find cleaner production methods more quickly. It’s imperative to find sustainable production methods at scale.

²Source: https://www.grandviewresearch.com/industry-analysis/hydrogen-generation-market ³Source: https://www.marketwatch.com/press-release/global-hydrogen-fuel-cell-vehicle-market-to-grow-with-healthy- cagr-2027-2019-01-16

The Next Step Towards a Hydrogen Economy 3 Water Electrolysis as a Means for Clean and Green Hydrogen Production

During the water electrolysis process, an elec- Renewables face a challenge of keeping energy trolyzer converts electricity and water into production consistent and reliable, matching gaseous hydrogen and oxygen, which can be supply with demand. Solar power generation stored for later use as an energy source. Unlike peaks at midday and ends at sunset—but, most hydrogen production methods, water elec- sometimes cloud cover interferes. trolysis doesn’t produce pollution or damaging Because peak energy consumption generally greenhouse gases as by-products of the conver- occurs between mid-afternoon to early eve- sion process. ning—with variations based on region and sea- Historically speaking, large-scale systems that son—energy supply can drop, with little means the water electrolysis process requires were to generate more. Hydrogen production, via considered costly and inefficient. But, techno- electrolysis, can supplement these renewable logical advances have improved the economic energy gaps more sustainably. and commercial viability of water electrolysis Fuel cells—which use hydrogen and oxygen systems. Many industry experts predict that to produce electricity—can also compensate future energy conversion and storage will use for times of lower energy production from water electrolysis for hydrogen production. renewables. Utility and grid operators can use commercial-scale systems to convert and store Hydrogen via Water Electrolysis Supports excess renewable power as hydrogen to supple- Other Clean Energy Applications ment higher demand. Water electrolysis and oth- Hydrogen generated by water electrolysis helps er clean energy applications can work in parallel stabilize electrical grids when they rely solely on to support a sustainable hydrogen economy. intermittent renewable sources like wind tur- bines and solar cells.

The Next Step Towards a Hydrogen Economy 4 Hydrogen Production Provides Versatile Solutions to Downstream Industries

Hydrogen production and storage can be used for more than just renewable energy generation, All of these applications—as well as more branching out and benefiting other markets, such as the transportation, agriculture, and sustainable technologies—stand to benefit from manufacturing industries that also need energy. dependable, consistent access to hydrogen. This demand for carbon-free hydrogen drives Automobile Fuel Cells innovation in the electrolysis process and membrane technology used to separate Unlike conventional vehicles that run on gasoline or diesel, fuel cell cars combine hydrogen and hydrogen from oxygen. oxygen to produce electricity that runs their motors. Classified as electric vehicles (EVs) because they’re powered entirely by electricity, the range and re-fueling processes of fuel cell vehicles compare favorably to conventional cars and trucks.

Ammonia Production

The expanding ammonia production market relies heavily on hydrogen. The agriculture industry needs hydrogen to produce ammonia, a basic ingredient in most fertilizers.⁴ When added to high-moisture grains, ammonia controls mold growth. It adds non-protein nitrogen to corn silage— the stored, fermented, high-moisture fodder fed to cattle, sheep, and other cud-chewing livestock. Hydrogen used in ammonia production also yields by-products used in pharmaceuticals and plastics.

Hydrodesulfurization of Petroleum Products

Hydrogen is used to hydrodesulfurize fuels in the oil refining process. This catalytic chemical reaction reduces sulfur from petroleum products, including gasoline, kerosene, jet fuel, fuel oil, diesel, and natural gas.

⁴Source: https://www.grandviewresearch.com/industry-analysis/hydrogen-generation-market

The Next Step Towards a Hydrogen Economy 5 Differentiating Types of Water Electrolysis

Currently, there are two main types of systems commercially available: alkaline and proton exchange membrane (PEM) water electrolyzers. Both alkaline and PEM technologies can deliver on-site and on-demand hydrogen, as well as ultrapure, dry, and carbon-free hydrogen.

Alkaline Electrolysis Proton Exchange Membrane (PEM)

In this process, the reaction occurs in a solution In this process, a PEM conducts protons from composed of water and potassium hydroxide the anode to the cathode, while providing (KOH) liquid electrolyte between two electrodes. electrical insulation to the electrodes. When the two electrodes receive sufficient volt- Negatively charged oxygen molecules give up age, the cathode water molecules take electrons electrons at the anode to make protons, elec- to form OH (hydroxide) ions and H2 (hydrogen) trons, and O2 when a potential difference (volt- molecules. age) is applied between the two electrodes. OH ions travel through the KOH electrolyte H⁺ ions travel through the proton-conducting toward the anode, where they combine and re- membrane towards the cathode, where they lease extra electrons to make water and oxygen combine with the electrons to make H2. (O2). A diaphragm with micrometer-sized pores The PEM allows only the positively charged ions prevents hydrogen and oxygen from mixing. to pass through to the cathode.

The Next Step Towards a Hydrogen Economy 6 Choosing the Right Water Electrolyzer

Issues with Alkaline Membrane Electrolyzers Advantages of PEM

While systems that use alkaline membranes cost Proton exchange membrane (PEM) water electrolysis provides a better alternative when paired with less, they have experienced performance issues intermittent power sources. While the historical high cost of PEM components limited the system’s in renewable energy applications. use in large-scale commercial applications in the past, recent technology developments have shrunk costs considerably—making PEM components more feasible options in many new use cases. Hydroxide support across the diaphragm inside alkaline electrolyzers responds slowly to power Proton exchange membrane water electrolyzers offer several advantages that make them well suited input, limiting the electrochemical reaction and for the demands of twenty-first century hydrogen production. leading to low current density. The diaphragm’s Proton exchange membranes can: porous structure allows the diffusion and mix- ture of hydrogen and oxygen when operating at • Operate at high current density that results in reduced costs, especially for systems coupled a low density, which limits its operational safety with very dynamic energy sources—like wind and solar—where sudden spikes in energy input range. would otherwise result in uncaptured energy Conventional electrodes used in alkaline electrolyzers tend to have low surface areas, poor • Work with a very thin membrane, even at high pressures, because of their polymer electrolyte catalyst utilization, and associated voltage • Deliver higher energy efficiency losses. These issues lead to low power density because their proton membrane has lower ohmic losses and require larger systems to support these • Exhibit a low gas crossover rate, which yields very high product gas purity critical for storage electrodes. safety and direct use in fuel cells

• Operate without corrosive chemicals

Proton exchange membranes can also be used in smaller systems because they operate at high power density. Alkaline water electrolysis can require up to ten times the footprint of PEM water electrolysis—an important consideration for customers with space restrictions.

The Next Step Towards a Hydrogen Economy 7 Advances in Membrane Technology

Technological advances and innovative mem- polymer permeable to many cations and polar Their physical reliability helps facilitate easier brane research have risen to meet the challenge compounds. Cation and polar compound sizes handling, resist operational upsets, and main- of identifying and addressing evolving require- and electrical properties determine their mo- tain reliable performance over the membrane’s ments of PEM electrolyzers. bility through the polymer. The membrane can lifetime. reject anions and non-polar species. Chemours researchers continue to develop Chemours scientists in collaboration with part- Nafion™ membranes, which are made from an ion Proton exchange membrane electrolyzers ners are also designing the next generation of exchange polymer. This perfluorinated polymer use membranes like Nafion™ N115 and N117 Nafion™ membranes and dispersions to operate provides chemical and thermal stability. because they offer high conductivity, reliability, in higher temperature ranges and lower humidi- and performance that current and future water ty. Hence, even in the most demanding operating Perfluorinated cation exchange sites attached electrolysis applications need. conditions, you can count on the efficiency of to the perfluorinated polymer chains make the our membranes and dispersions.

The Next Step Towards a Hydrogen Economy 8 Reinventing the Energy Market with Nafion™ Membranes

With over 50 years of experience, the Nafion™ membranes and dispersions team has the knowledge to lead the energy industry on the journey toward a safer, cleaner world. Nafion™ ion exchange membranes have been the It’s time to let the future in. Won’t you join us? products of choice for chlor-alkali electrolysis, providing unparalleled performance and durability. Today, Nafion™ membranes also offer leading- edge solutions for energy storage, fuel cells, water electrolysis, ultra-high For more information, visit Nafion.com or call one of our technical experts: purity chemical production, and other specialty applications. United States and Canada �� +1 844 773 2436 or +1 302 773 1000 Nafion™ membranes by Chemours deliver: Asia Pacific – North �� +86 400 8056 528 Asia Pacific – South �� +91 124 479 7400 Superior chemical stability and proton conductivity Europe/Middle East/Africa �� +41 22 719 1500 The structure of Nafion™ membranes consists of a flexible, hydrophobic Brazil �� 0800 110 728 backbone that provides excellent mechanical and chemical stability, while its pendent groups deliver high proton conductivity. Mexico...... 1 800 737 5623 or +55 55 5125 4907(DF)

Adaptabilty for alternative electrolyte systems Built from Chemours’ strong knowledge base and industry experience, Nafion™ membrane properties—like ion conductivity and crossover—are tunable at various levels using monomer, polymer, and membrane processing techniques.

Proven performance from industry-leading field experience Nafion™ ion exchange membranes have served as the benchmark material across several industries.

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