A Hydrogen Economy and Fuel Cells: An Overview

Order Code RL32196

CRS Report for Congress

Received through the CRS Web

A Hydrogen Economy and Fuel Cells:

An Overview

January 14, 2004

Brent D. Yacobucci

Analyst in Energy Policy

Resources, Science, and Industry Division

Aimee E. Curtright

Visiting Scholar

Resources, Science, and Industry Division

Congressional Research Service ˜ The Library of Congress

A Hydrogen Economy and Fuel Cells: An Overview

Summary

There is growing interest in the use of hydrogen as the main fuel for stationary,

mobile, and transportation applications, especially using fuel cells. This is

particularly true in light of the Bush Administration’s efforts to increase research and

development for these technologies. In his January 2003 State of the Union Address,

President Bush announced a new, five-year research initiative on hydrogen fuel and

fuel cells. This effort is a key component of the Administration’s proposed energy

policy.

Policymakers are interested in hydrogen and fuel cells because they could

potentially lead to significant societal benefits. Depending on how the fuel is

produced and distributed, hydrogen fuel and fuel cells could help significantly reduce

pollution and greenhouse gas emissions. Further, if hydrogen were produced using

domestic energy supplies, it could help reduce dependence on imported petroleum.

Also, fuel cells could be used to improve the efficiency and reliability of electricity

generation.

However, there are some key barriers to the development of a “hydrogen

economy.” Most importantly, the current cost of both fuel cells and hydrogen fuel

makes them uncompetitive for most applications. Reducing these barriers is one of

the driving factors in the government’s involvement in hydrogen and fuel cell

research and development. But this involvement raises concerns, including the cost

of such research and the possibility of the government “picking winners” among

competing technologies.

This report discusses six key questions related to the hydrogen economy and

fuel cells: 1) what is hydrogen fuel; 2) what is a fuel cell; 3) how will hydrogen fuel

be used; 4) where will hydrogen fuel come from; 5) what would it mean to move to

a hydrogen economy; and 6) what role can Congress play. This report will be

updated annually, or as events warrant.

Contents

What is hydrogen fuel? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

What is a fuel cell? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

How will hydrogen fuel be used? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Where will hydrogen fuel come from? . . . . . . . . . . . . . . . . . . . . . . . . . 4

What would it mean to move to a hydrogen economy? . . . . . . . . . . . . . 7

What role can Congress play? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

List of Figures

Figure 1. A Basic Fuel Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Figure 2. Hydrogen Pathways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

A Hydrogen Economy and Fuel Cells:

An Overview

Hydrogen is a chemical that can be produced using any primary energy source.

Its use as a fuel could lead to lower emissions of pollutants and greenhouse gases.

Further, depending on which primary energy supply is used, hydrogen fuel could help

reduce energy imports, especially for transportation. A major use of hydrogen would

be in fuel cells. A fuel cell is a device that produces electricity through a chemical

process, as opposed to combustion. Fuel cells have the potential to achieve

significantly higher efficiencies (i.e. produce more power for a given energy input)

than combustion engines1 and conventional power plants.

The prospect of hydrogen becoming the main fuel for all energy-related

applications, a “hydrogen economy,” and the continuing development of fuel cells

to utilize hydrogen fuel has generated growing interest within the policy realm. This

is especially true after two key initiatives by the Bush Administration:2 the

FreedomCAR initiative to promote cooperative research and development between

the federal government and the major American automakers on fuel cell vehicles; and

the President’s Hydrogen Fuel Initiative to promote federal research and development

on hydrogen fuel and non-automotive fuel cell technology.

This push for research on hydrogen and fuel cells has led to some basic

questions about the function and use of the new technologies. Six key questions

related to a hydrogen economy and fuel cells are:

! What is hydrogen fuel?

! What is a fuel cell?

! How will hydrogen fuel be used?

! Where will hydrogen fuel come from?

! What would it mean to move to a hydrogen economy?

! What role can Congress play?

What is hydrogen fuel? A fuel is any high energy substance that can be

consumed to produce useful work. Examples include gasoline used to propel an

automobile and coal used to generate electricity at a power plant. Hydrogen can also

be used as a fuel, and is the most abundant element in the universe. However,

hydrogen is not a primary fuel. That is, it does not occur naturally but instead is

found most often as part of a larger molecule, such as water or petroleum. Today,

1

For more information on transportation fuel cell applications, see CRS Report RL30484,

Advanced Vehicle Technologies: Energy, Environment, and Development Issues.

2

For more information on these initiatives, see CRS Report RS21442, Hydrogen and Fuel

Cell Vehicle R&D: FreedomCAR and the President’s Hydrogen Fuel Initiative.

CRS-2

most hydrogen is extracted by processing (reforming) methane (natural gas) at oil

refineries and chemical plants.3 However, in the future hydrogen could potentially

find widespread use as a fuel, either burned in combustion engines or combined with

oxygen in fuel cells.4 Both methods produce useful energy, either as motion or

electricity, and both generate waste.5

To produce hydrogen fuel, two key components are necessary: energy and

hydrogen atoms. In some cases, for example using natural gas, both components are

supplied simultaneously as hydrogen atoms are separated from the methane

molecule. In other cases, the two components are supplied separately. For example,

electricity can be used to separate hydrogen from water to generate hydrogen fuel.6

What is a fuel cell? A fuel cell is an electrochemical device that uses

hydrogen (or a hydrogen-rich fuel) and oxygen to produce electricity.7 It is physically

and chemically similar to a battery, but as the name implies, fuel cells make use of

an input fuel. They can be refueled at any time, and do not run down or need to be

recharged, making them similar to combustion engines in their use. However, fuel

cells utilize chemical processes that are inherently more efficient than combustion.

For example, a typical combustion-based fossil fuel power plant operates at about

35% efficiency,8 while a fuel cell electricity generator can operate at 40 to 60%

efficiency.9 As such, fuel cells could potentially provide energy more cleanly and

efficiently than combustion engines.

There are many varieties of fuel cells, but they are all related by a single

common chemistry. One type of fuel cell, a polymer electrolyte membrane (PEM)

cell, is shown in Figure 1.10 All fuel cells have three basic components: (1) an

3

The majority of this hydrogen is used by the refiner or chemical company onsite in the

production of other chemicals. For example, hydrogen is used at refineries to remove sulfur

from gasoline and diesel fuel.

4

For more on hydrogen fuel, see

[http://www.eere.energy.gov/hydrogenandfuelcells/hydrogen/]. Accessed November 13,

2003.

5

U.S. Department of Energy (DOE), Fuel Cell Report to Congress. February 2003.

6

These processes are explained further in the section “Where will hydrogen fuel come

from?”

7

DOE, How Fuel Cells Work.

http://www.eere.energy.gov/hydrogenandfuelcells/fuelcells/how.html. Accessed November

13, 2003.

8

Approximately 35% of the chemical energy contained in the fuel is converted into electrical

energy. The remainder is lost as waste heat.

9

If electricity and useful heat are generated simultaneously (cogeneration), efficiencies can

reach 85%. U.S. Department of Energy, “Why Are Hydrogen and Fuel Cells Important?”

[http://www.eere.energy.gov/hydrogenandfuelcells/fuelcells/why.html]

10

Downloaded on November 13 from the Department of Energy, Energy Efficiency and

Renewable Energy website.

(continued...)

CRS-3

anode, (2) a cathode, and (3) an electrolyte that

separates them. The hydrogen fuel flows to the anode,

where the electrons are removed and shuttled to the

cathode through an external circuit to produce

electricity. Oxygen (or another oxidant) is used at the

cathode. When the oxygen, the positively charged

hydrogen, and the electrons combine, water and heat

are generated as waste, and the process is complete.

The location of this chemical combination within the

fuel cell, and the exact details of the chemical process

vary with the type of fuel cell. However, all types

generate electricity by first isolating the hydrogen from

the oxygen, and then requiring electrons to flow

through an external circuit before these three

components combine.11

Figure 1. A Basic

Fuel Cell

The power output from a single cell is relatively

low. However, fuel cells are usually arranged in “stacks” to provide the necessary

voltage to power a building or a car. Because of this, fuel cells can be sized to power

any application, from a small cell phone to a large power plant.

While most fuel cells operate on pure hydrogen, some cells can operate on

hydrogen-rich (hydrocarbon) fuels. One example is a direct methanol fuel cell

(DMFC), which feeds methanol directly into the cell. In this case, the cell emits

carbon dioxide and potentially other compounds, as well as water and heat.

Hydrogen fuel cells can also be operated on other hydrocarbon fuels (including

gasoline and natural gas) if a reformer is used along with the fuel cell. A reformer

acts as a mini-refinery to separate the hydrogen from the other elements in the fuel.

The use of a reformer or a direct methanol fuel cell could eliminate concerns over

hydrogen production and storage, but would result in higher in-use emissions,

compared to a hydrogen fuel cell.12

How will hydrogen fuel be used? Fuel cells and hydrogen could

potentially meet any energy requirement. While some fuel cell systems are

commercially available today, most applications are still under development. For

example, fuel cell electrical power generation is presently in use in commercially

available backup power applications, but the most advanced automotive fuel cells are

still in the prototype stage. Fuel cell automobiles, trucks, and buses are being

demonstrated worldwide, but at present are very expensive. Further, fuel cells are

being studied for smaller, mobile applications such as notebook computers and cell

phones. In addition to fuel cell applications, hydrogen fuel can be combusted in

10

(...continued)

http://www.eere.energy.gov/hydrogenandfuelcells/fuelcells/types.html

11

For more information on fuel cells, see [http://fuelcells.si.edu/index.htm] and

[http://www.fuelcells.org/whatis.htm].

12

Depending on the efficiency of the reformer and fuel cell, as well as the characteristics

of the fuel used, even using a reformer (as opposed to pure hydrogen) a fuel cell system can

achieve lower overall emissions than conventional systems.

CRS-4

specially designed automobile engines or power generation systems, although

currently the advantages of fuel cells appear to outweigh those of hydrogen

combustion.

There are several fuel cell technologies currently in various stages of

development. The demands of a particular application generally determine the choice

of technology to be applied.13 For example, phosphoric acid fuel cells are

commercially available today, mainly in larger stationary power generation

applications. However, these fuel cells operate at relatively high temperatures (from

300 to 400 degrees F) , so they are not practical in many applications. Proton

exchange membrane (PEM) fuel cells operate at relatively low temperatures (around

175 degrees F) and can vary their output quickly. PEM technology is seen as the

most likely fuel cell for automotive applications. Other types include molten

carbonate, solid oxide, and alkaline fuel cells. Each of the various types faces

technical barriers that include cost,14 fuel supply,15 and durability.

Where will hydrogen fuel come from? Several factors will affect future

supplies of hydrogen. As stated above, hydrogen itself is not a primary energy

source, and must be generated using energy and a supply of hydrogen atoms.16 In

addition to production issues, there are concerns over supplying hydrogen to endusers, as there is little current infrastructure for hydrogen fuel storage and

distribution.

Sources of hydrogen. One key advantage of using hydrogen as a fuel is that

virtually any primary energy source can be used to generate it. (See Figure 2.17) A

major motivation for the hydrogen economy is the potential to use environmentally

benign, domestic, and/or sustainable energy sources. Hydrogen can be produced

either by reforming hydrocarbon fuels or by splitting water.

Hydrocarbon fuels include fossil fuels (crude oil, coal, and natural gas) and

biomass such as alcohol (e.g. methanol produced from landfill methane or ethanol

produced from corn). Hydrocarbons must be reformed to produce hydrogen. This

is significantly more expensive than using gasoline directly. According to one

producer’s analysis, in automotive applications, hydrogen reformed from natural gas

is projected to cost roughly twice as much as gasoline at the pump.18 Further, this

13

For more information on the many applications currently being tested, see

[http://www.fuelcells.org/charts.htm]. For more information on the types of fuel cells, see

[http://www.fuelcells.org/fctypes.htm].

14

One major contributor to cost is raw materials such as precious metals (e.g. platinum)

which are used as catalysts.

15

Some cells require extremely pure fuel.

16

In certain applications, hydrogen may not be the most suitable fuel. Instead, a hydrogenrich primary fuel may be appropriate for direct use in the fuel cell.

17

18

Reproduced with permission from General Motors Corporation.

Hydrogen produced from natural gas is projected to cost roughly 8 cents per mile, as

opposed to 4 cents per mile for gasoline. Cost per mile estimates from “Long-Term Energy

(continued...)

CRS-5

does estimate does not include the cost of converting infrastructure to deliver the

fuel.

Figure 2. Hydrogen Pathways

Hydrogen can also be produced using electricity to split water (electrolysis) in

an electrolyzer. If electricity is generated with nuclear, hydroelectric, wind or solar

energy rather than fossil fuels, this could present a lower-emission and/or more

sustainable option. However, there are environmental concerns associated with these

electricity sources, especially nuclear energy. Electrolysis is also significantly more

expensive than hydrocarbon reformation.19 Chemical or thermochemical hydrolysis

can also be used to produce hydrogen by splitting water, but these techniques are also

more expensive than reformation.20 However, future technological advances could

potentially make these production techniques more economically attractive.

Infrastructure. If an economically viable and environmentally benign method

of hydrogen production were identified, the transport, storage, and delivery of

18

(...continued)

Outlook,”Walter Buchholtz, Exxon-Mobil. Feb. 26, 2003.

19

Exxon-Mobil projects that hydrogen from electrolysis could be more than twice as

expensive as hydrogen from natural gas (and more than four times as expensive as gasoline).

Exxon-Mobil, op. cit.

20

DOE, op. cit.

CRS-6

hydrogen could still make a true “hydrogen economy” prohibitively expensive and

difficult to implement. Even if fuel cells were advanced significantly beyond today’s

technology, the United States currently lacks both the physical and regulatory

infrastructure necessary to rely on hydrogen gas as a major energy carrier.

Issues for hydrogen infrastructure include: safety codes and standards, such as

fire and building codes; public awareness about hydrogen fueling systems, which

would be significantly different from conventional fueling systems; and training for

fuel distribution and safety personnel in the physical and chemical properties of

hydrogen, which differ vastly from fossil fuels. For example, hydrogen is an

extremely flammable gas, but it is less dense than any other fuel, and tends to

dissipate quickly in open spaces.

The required infrastructure will depend on the method and location of hydrogen

production. Generation of hydrogen gas at centralized facilities would require

transportation, storage and delivery of a gas or super-cooled liquid. In contrast,

distributed hydrogen production, such as small-scale natural gas reformation at

service stations, homes, and offices, would require a significant supply of energy

(likely electricity or natural gas), as well as on-site storage facilities. The

convenience and safety of the delivery would need to match that experienced by

consumers today with natural gas and gasoline. Creating an extensive hydrogen

infrastructure could allow for multiple feedstocks and could diversify the system in

the event of changing or evolving fuel sources. Nevertheless, it is doubtful that a

widespread system of hydrogen distribution will emerge quickly. More likely,

transition fuels, such as natural gas and ethanol, and niche applications, such as

backup power, will pave the way.

Applications: Stationary vs. Mobile. Stationary and distributed applications

present the fewest challenges in infrastructure. These applications can include

backup power for office buildings and power supplies for remote locations. Relative

to mobile applications (e.g. transportation), storage requirements will be technically

less difficult to meet and distribution will be less widespread, especially if on-site

reformation is used.21 Indeed, stationary systems are the only commercially available

fuel cells today. In the future, transition niche applications including delivery trucks,

taxis, and other fleet vehicles could help demonstrate the viability of hydrogen and

fuel cells for mobile applications.22

Depending on the application, it may be more cost-effective or more compatible

with existing infrastructure and codes to use conventional fuels rather than hydrogen

in fuel cells. This is particularly likely in the near-term. Electricity deregulation, grid

reliability issues, and the attractiveness of heat/electricity co-generation may motivate

a general move to distributed power, and fuel cell technology may help satisfy the

requirements of this change. In the near-term, natural gas will likely be the fuel for

stationary applications, with propane a potential fuel for remote applications.

21

DOE, op. cit.

22

[http://www.hydrogenus.org/implementationplan.asp]

CRS-7

Longer-term markets, such as transportation, may make use of hydrogen gas

directly in the fuel cell device, but a choice may still be required between on-board

hydrogen gas generation from gasoline or alcohol fuels carried on the vehicle vs. offboard hydrogen production distributed through hydrogen fueling stations. Off-board

hydrogen generation requires on-board storage of gaseous or liquid hydrogen,

necessitating a unique and more demanding vehicle infrastructure and possibly

limiting driving range. But the advantages of increased efficiency and simplicity

could ultimately make hydrogen the more attractive choice, assuming the problems

associated with infrastructure and regulation are not insurmountable.23

What would it mean to move to a hydrogen economy? A hydrogen

economy would rely on hydrogen as the primary fuel for transportation, power,

heating, and other applications. Hydrogen fuel could be used in fuel cells to generate

electricity and heat in cogeneration plants. Fuel cells could replace petroleum-fueled

internal combustion engines in transportation, and those same fuel cells could be

used to power electrical appliances when the vehicle is not in use. Depending on

how it is produced, hydrogen fuel could help improve fuel supply stability, while

lowering or eliminating emissions of pollutants (e.g. nitrogen oxides, carbon

monoxide, sulfur dioxide, mercury) and greenhouse gases (e.g. carbon dioxide,

methane).

Major air quality benefits could be derived from the expanded use of hydrogen.

For example, using hydrogen fuel generally produces only water vapor and heat as

byproducts. Therefore, if the supply-related emissions from hydrogen fuel are

relatively clean, overall “fuel cycle” pollutant emissions, as well as greenhouse gas

emissions, could be significantly reduced. Compared to other fuels, a key advantage

of hydrogen is that emissions of pollutants and greenhouse gases may be easier to

control when produced from fewer centralized sources, as opposed to many mobile

sources. However, there may also be the potential for higher overall emissions,

depending on the primary energy source. For example, hydrogen produced from coal

could lead to higher overall emissions, if the hydrogen replaced gasoline in

combustion engines.

In addition to air quality improvements, there are several other potential

benefits. First, because hydrogen can be produced from any primary energy source,

a focus on the use of domestic resources could provide energy security gains. In a

hydrogen economy, consumers could potentially purchase hydrogen like they

purchase other fuels today. Suppliers would be free to select the most economical

primary energy source and processing methods. However, as discussed above, there

are key technical concerns with making this supply seamless to the customer,

especially in delivering and storing hydrogen fuel.

Another potential benefit comes from the ability to improve the reliability of the

electricity production. Because hydrogen can be produced from electrolysis, there

is the potential to use existing electrical generation capacity during low-load times

(such as late at night). Further, stationary and mobile fuel cells that would otherwise

be idle (e.g. a fuel vehicle parked in a garage) could be used to produce electricity

23

DOE, op. cit.

CRS-8

that could be used on-site or returned to the grid. However, these sorts of changes

would require significant investments in electrical infrastructure.

A transition to a hydrogen economy would be expensive, requiring major

investments in production facilities, supply networks, and distribution systems. In

addition, consumers would need to finance the purchase of new equipment, possibly

including stationary generation systems and fuel cell vehicles. However, the

potential benefits in terms of air quality improvements, energy security, and

greenhouse gas mitigation could be significant, especially if some key technological,

economic, and policy barriers–including supply and storage issues, as well as safety

concerns–are overcome.

What role can Congress play? Determining the proper role of the

government in the development of a hydrogen economy has raised some key issues.

Some of these issues are common to all technical and scientific research and

development. Examples of these issues include whether the government should be

“picking winners,” and whether the government should involve itself in research that

will ultimately profit corporations. On the other hand, the potential benefits to

society of hydrogen and fuel cells are seen as key reasons for promoting research and

development, as these benefits could lead to significant gains, such as improved air

quality and greater energy security. Other key issues include whether there are other

technologies such as renewable energy or hybrid vehicles that could promote the

same goals more economically or with fewer technical, economic, and policy

barriers.

Oversight of the Administration’s Proposal. A s p a r t o f t h e B u s h

Administration’s National Energy Policy, the Department of Energy (DOE) has

worked to identify key barriers to the development of a hydrogen economy and

opportunities for increased research. Out of that effort, DOE produced two key

documents, a National Hydrogen Roadmap (November 2002) and a Fuel Cell Report

to Congress (February 2003) outlining necessary next steps. In January 2003, the

Administration announced a major hydrogen research and development push–the

President’s Hydrogen Fuel Initiative. The Administration is seeking to increase

funding for hydrogen and fuel cell research and development, mainly through the

Department of Energy.24 The Administration has requested a total of $1.8 billion for

FY2004 through FY2008, including $720 million in new money. This initiative

would transfer some funds from research on other topics, such as hybrid electric

vehicles (while maintaining that research at reduced levels). The research initiative

has three key components: hydrogen fuel development; fuel cell development

(especially for stationary applications); and development of hydrogen-fueled

automobiles.

Through the annual appropriations process, Congress will address the

Administration’s request for increased funding. Further, through funding

24

The President's Hydrogen Fuel Initiative is meant to complement the FreedomCAR

initiative, which coordinates research and development on fuel cell vehicles. This initiative

is a cooperative research partnership between the federal government and the "Big Three"

American auto manufacturers (DaimlerChrysler, Ford, and General Motors).

CRS-9

authorizations in comprehensive energy legislation (H.R. 6), Congress has the

opportunity to support or reject the Administration’s research and development plans

for the next several years.

Other Congressional Actions.

There are other opportunities for

Congressional action to encourage or support hydrogen and fuel cell development as

well. For example Congress could develop statutes and regulatory systems to

simplify codes and standards for the transportation and use of hydrogen, as well as

the siting of hydrogen supply facilities. Further, Congress could establish tax credits

and other incentives to promote the expanded use of hydrogen fuel and fuel cell

technologies. In addition, Congress could require the federal government to set an

example as an “early adopter” of hydrogen fuel and fuel cell technologies.

Conclusion. There are several key barriers to the development of hydrogen

fuel, fuel cells, and a hydrogen economy. These barriers include technical feasibility,

economic cost, consumer acceptance, and safety. These issues will be addressed over

a long-term time frame, and will evolve as research and technology expands options

for hydrogen and fuel cell use. Basic understanding of the long-term potentials and

limitations surrounding a hydrogen economy is critical to assessing such changes.