Electrolysis of Water: Can AU do this?

Electrolysis is the process by which water molecules are split directly into hydrogen and oxygen molecules using electricity and an electrolyzer device. The overall electrolysis reaction is:

e- + H2O -> 1⁄2 O2 + H2

The two most common types of electrolyzers are alkaline (use a potassium hydroxide electrolyte) and PEM (use a solid polymer membrane electrolyte). A schematic of an alkaline electrolysis system is provided in below. The electrolysis reaction produces pure oxygen as a by-product along with pure hydrogen. The oxygen can then be used for other productive purposes. 

Hydrogen can be produced via electrolysis of water from any electrical source, including utility grid power, solar photovoltaic (PV), wind power, hydropower, or nuclear power. Electrolysis is currently done at a wide range of scales, from a few kW to up to 2,000 kW per electrolyzer.

There is a great potential for AU to use this technology, becoming a pioneer and becoming the first University in the US to have a fuel cell system on campus that is run on renewable hydrogen.

Because AU had already looked into the use of fuel cell systems but turned it down due to the non-renewable sources of hydrogen available at the time, the potential to acquire renewable sources of hydrogen change the equation.

Could AU implement a system like this?

If they could do it...why couldn't AU?

Fuel Cell Energy Project Highlights at two U.S. Universities

Central Connecticut State University (CCSU)

• FuelCell Energy, Inc. installed an ultra-clean, efficient and reliable 1.4 megawatt Direct FuelCell^®  power plant that meets approximately 35 percent of the campus power needs.

• On-site power generation supports the University micro-grid, which ensures continuous power availability to critical campus buildings in the event of a disruption of the electric grid.

• The campus and University System benefit with favorable economics that generate an estimated $100,000/ year in savings. 

CCSU Project fact Sheet 

California State University Northridge (CSUN)

• CSUN installed a one megawatt (1 MW) stationary fuel cell power plant system from FuelCell Energy^®

• Approximately 18% of the university's baseload power requirement is met by the fuel cell power plants. 

• The power plant also reduces greenhouse gas emissions of CO2 by more than 6,400 tons per year

CSUN Project fact Sheet  

DOE News - Cost Competitive Hydrogen Fuel by 2020

Hydrogen can be produced using diverse, domestic resources including fossil fuels, such as natural gas and coal (with carbon sequestration); nuclear; biomass; and other renewable energy technologies, such as wind, solar, geothermal, and hydro-electric power.

The overall challenge to hydrogen production is cost reduction. For cost-competitive transportation, a key driver for energy independence, hydrogen must be comparable to conventional fuels and technologies on a per-mile basis in order to succeed in the commercial marketplace.

Could this be the start?

Energy Department Announces New Investment to Advance Cost-Competitive Hydrogen Fuel

Why use Hydrogen as an energy fuel in the first place?

Hydrogen is a very good energy vector; with an energy density of 33 kWh per kilogramme, hydrogen contains three times more energy than diesel and 2.5 times more energy than natural gas.

The future fuel cells is on hydrogen-production technologies that result in near-zero, net greenhouse gas emissions and use renewable energy sources, or nuclear energy.

• ·          Hydrogen, chemical symbol "H", is the simplest element on earth. An atom of hydrogen has only one proton and one electron. 

• ·     Hydrogen gas has two atoms of hydrogen, which is why pure hydrogen is commonly expressed as "H2")

• ·     Although very abundant on earth, hydrogen rarely exists by itself as it normally combines readily with other elements and is almost always found as part of another substance, such as water, hydrocarbons, or alcohols.

• ·     Hydrogen is an energy carrier, not an energy source. Hydrogen can store and deliver usable energy, but since it rarely exists in nature, it must be produced from compounds that contain it.

• ·     Hydrogen can be produced via various renewable process technologies, including thermal (natural gas reforming, renewable liquid and bio-oil processing, and biomass and coal gasification), electrolytic (water splitting using a variety of energy resources), and photolytic (splitting water using sunlight via biological and electrochemical materials).

• ·     In order for hydrogen to be successful in the market place however, it must be cost-competitive with the available alternatives. 

Fuel Types: What is the best fit for AU?

Types of Fuel Cells

Basic Overview: Generate electricity through electrochemical processes, rather than combustion.

Principle Types:                     

1. Alkaline fuel cell (AFC),
2. Proton exchange membrane (PEM) fuel cell,
3. Direct methanol fuel cell (DMFC),
4. Molten carbonate fuel cell (MCFC),
5. Phosphoric acid fuel cell (PAFC),
6. Solid oxide fuel cell (SOFC). 

Each fuel cell type has its own unique chemistry, such as different operating temperatures, catalysts, and electrolytes.  A fuel cell’s operating characteristics help define its application.

1) Proton Exchange Membrane Fuel Cell (PEM)

Electrolyte:                            Solid polymer membrane

Catalyst:                                Platinum is the most active catalyst for low-temperature fuel cells

Operating Temperature:       Around 175-200⁰F

Electrical Efficiency:             40-60 percent

Fuel Basics:                            PEM fuel cells operate at relatively low temperatures, have high power density, and can vary output quickly to meet shifts in power demand.  PEMs are fueled with hydrogen gas, methanol, or reformed fuels.

Applications:                          PEMs are well-suited to power applications where quick startup is required, such as automobiles or forklifts.  Single PEM units range from several watts to several kilowatts, and can be scaled into larger systems – the largest to date is a 1 megawatt PEM stationary power plant.  PEM systems are available today for a variety of applications, with sales focused in the telecommunications, data center and residential markets (primary or backup power), and to power forklifts and other material handling vehicles.  PEM fuel cells are also used in buses and demonstration passenger vehicles – major auto manufacturers anticipate the start of commercial fuel cell vehicle sales around 2014-2016. 

2) Direct Methanol Fuel Cell (DMFC)

Electrolyte:                             Solid polymer membrane

Catalyst:                                 Platinum is the most common

Operating Temperature:        Around 125-250⁰F

Electrical Efficiency:              Up to 40 percent

Fuel Basics:                            DMFCs are similar to PEM fuel cells in that they both use a polymer membrane as the electrolyte.  However, in DMFC systems the anode catalyst itself draws the hydrogen from liquid methanol, eliminating the need for a fuel reformer.  

Applications:                          The low operating temperature makes DMFCs attractive for miniature applications such as cell phones, laptops, and battery chargers for consumer electronics, to mid-size applications powering electronics on RVs, boats, or camping cabins.

3) Alkaline Fuel Cell (AFC)

Electrolyte:                              Potassium hydroxide solution in water

Catalyst:                                  Can use a variety of non-precious metal catalysts

Operating Temperature:        Around 225-475⁰F

Electrical Efficiency:              60-70 percent

Applications:                          NASA has used hydrogen-fueled AFCs on space missions since the 1960s to provide both electricity and drinking water.  AFCs are poisoned easily by small quantities of CO2, and are thus deployed primarily in controlled aerospace and underwater environments.

4) Phosphoric Acid Fuel Cell (PAFC)

Electrolyte:                             Liquid phosphoric acid ceramic in a lithium aluminum oxide matrix

Catalyst:                                 Carbon-supported platinum catalyst

Operating Temperature:        350-400⁰F

Electrical Efficiency:               36-42 percent (85% with co-generation of heat & power)

Fuel Basics:                            PAFCs can operate using reformed hydrocarbon fuels or biogas.  Anode and cathode reactions are similar to PEMs, but since operating temperatures are higher, PAFCs are more tolerant of fuel impurities.  PAFCs are frequently used in a cogeneration mode, in which byproduct heat is captured for onsite heating, cooling, and hot water (also called combined heat and power, or CHP).  

Applications:                          PAFCs are commercially available today with systems operating around the world at high-energy demand sites such as hospitals, schools, office buildings, grocery stores, manufacturing or processing centers, and wastewater treatment plants.

5) Molten Carbonate Fuel Cell (MCFC)

Electrolyte:                             Typically consists of alkali (Na & K) carbonates retained in a ceramic matrix of LiHO2

Catalyst:                                 High MCFC operating temperature permits the use of lower-cost, non-platinum group catalysts

Operating Temperature:       Around 1,200 ⁰F

Electrical Efficiency:             50-60 percent (85% with co-generation of heat & power)

Fuel Basics:                           The high operating temperatures of MCFCs means that hydrocarbon fuels can be converted to hydrogen within the fuel cell itself (internal reforming).  MCFCs are not prone to CO or CO2 “poisoning” – they can even use carbon oxides as fuel – making them more attractive for fueling with gases made from coal.  

Applications:                          MCFCs are ideal for large stationary power and CHP applications, and are available as commercial products, with dozens of power plants deployed at food and beverage processing facilities, manufacturing plants, hospitals, prisons, hotels, colleges and universities, utilities, and wastewater treatment plants worldwide.

6) Solid Oxide Fuel Cells (SOFC)

Electrolyte:                             A solid ceramic, typically yttria-stabilized zirconia (YSZ)

Catalyst:                                 High SOFC operating temperature permits the use of lower-cost, non-platinum group catalysts.

Operating Temperature:       About 1,800⁰F

Electrical Efficiency:             50-60 percent (80% with co-generation of heat & power)

Basics:                                   High-temperature SOFCs are capable of internal reforming of “light” hydrocarbons such as natural gas, but heavier hydrocarbons (gasoline, jet fuel) can be used, though they require an external reformer.  

Applications:                          SOFCs are suitable for large stationary applications, and are being deployed across the country at data centers, office buildings and retail stores.  SOFCs are also being demonstrated for use as vehicle auxiliary power units and tested for small stationary applications, such as homes and apartments in the U.S., Japan, and Germany.

Other Fuel Cell Types

Regenerative Fuel Cells (RFCs)

Basics:                                    Closed-loop form of power generation.  Water is separated into hydrogen and oxygen by a solar-powered electrolyzer, and then is directed to the fuel cell, where electricity, heat and water are generated.  The byproduct water is re-circulated back to the electrolyzer where the process begins again.  PEM and SOFC regenerative fuel cell system systems are currently in development.

Zinc Air Fuel Cells (ZAFCs)

Basics:                                   Zinc pellets and air are combined with an electrolyte to create electricity, generating significantly more power than lead-acid batteries of the same weight.  ZAFC systems have potential use in transport applications.

Microbial Fuel Cells (MFCs)

Basics:                                    Using the catalytic reaction of microorganisms to convert virtually any organic matter (e.g. glucose, acetate, wastewater) into fuel.  Enclosed in oxygen-free anodes, organic compounds are consumed by bacteria or other microbes.  As part of the digestive process, electrons are pulled from the fuel and conducted into a circuit with the help of inorganic mediator chemicals.  MFCs operate in mild conditions between 68-104⁰F.  These systems are capable of efficiencies up to 50 percent, and will be suitable for small to miniature applications such as medical devices.

First Fuel Cell to Power Residential Building in New York

The Octagon, which is a LEED Silver 500-unit apartment community on Roosevelt Island, is the first residential building in the State of New York to be powered and heated by a 400 kilowatt (kW) fuel cell from UTC Power.

How it works

• The fuel cell (PureCell® System Model 400), is a combined heat and power (CHP) system. 
• It converts natural gas to electricity and heat through an electrochemical process to provide power and heat to meet the majority of the apartment building's energy demand.  
• The energy efficiency achieved by the fuel cell is significantly higher than the energy received from the grid and emissions are negligible.  
• The fuel cell's process heat is captured to satisfy the building's space heating and domestic water requirements.  
• The Octagon is a certified LEED Silver community, utilizing approximately 35% less energy than required by code.

Read the full article

First Fuel Cell to Power Residential Building in New York

Interesting article reviewing a 11.2 megawatt fuel cell production park — the world’s largest, according to FuelCell Energy — which is now operating in Daegu City, South Korea.


World’s largest fuel cell park is open for business