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Contract No. DE-AC36-08GO28308

Resource Assessment for 

Hydrogen Production

Hydrogen Production Potential from 

Fossil and Renewable Energy 

Resources

M. Melaina, M. Penev, and D. Heimiller

National Renewable Energy Laboratory

Technical Report

NREL/TP-5400-55626

September 2013
NREL is a national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC

This report is available at no cost from the National Renewable Energy

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Contract No. DE-AC36-08GO28308

National Renewable Energy Laboratory

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Resource Assessment for 

Hydrogen Production 

Hydrogen Production Potential from 

Fossil and Renewable Energy 

Resources

M. Melaina, M. Penev, and D. Heimiller

National Renewable Energy Laboratory

Prepared under Task No. HT12.2025

Technical Report

NREL/TP-5400-55626

September 2013
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iii 

Acknowledgments

Funding for this report came from the U.S. Department of Energy’s Fuel Cell Technologies 

Office within the Office of Energy Efficiency and Renewable Energy (EERE). The authors 

would also like to acknowledge and thank Tim Brown (University of California Irvine), Jim 

O’Brien (Idaho National Laboratory), Joan Ogden (University of California Davis), Susan 

Schoenung (Longitude 122 West, Inc.), and Nicholas Paduano (Energy Information 

Administration) for their comments and suggestions in reviewing earlier versions of this report.

The authors also thank Susan Hall (U.S. Geological Survey) for reviewing sections of the report 

related to uranium resources. Many improvements were made to the analysis and substance of 

the report in response to reviewer feedback. The analysis results presented here build upon 

analysis work and data preparation completed for earlier reports by Anelia Milbrandt and 

Maggie Mann (2007; 2009), Anthony Lopez, Donna Heimiller, and other NREL staff (Lopez et 

al. 2012); these earlier reports are cited when directly referenced. This analysis also builds upon 

the framework for comparing future hydrogen demands to projected energy supply trends in the 

2011 Program Plan for the U.S. Department of Energy’s Fuel Cell Technologies Office (DOE 

2011a). These previous efforts facilitated the process of updating data and resource analyses and

provided a general framework for discussing energy resources and hydrogen production 

potentials. Any remaining errors or shortcomings of this report are the responsibility of the 

authors. 

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at www.nrel.gov/publications.
iv 

Acronyms

AEO Annual Energy Outlook

AER Annual Energy Report

BAU business as usual

Btu British thermal units

CCS carbon capture and storage

CSP concentrating solar power

DOE U.S. Department of Energy

DRB Demonstrated Reserve Base

EERE Energy Efficiency and Renewable Energy

EIA U.S. Energy Information Administration

ERR Estimated Recoverable Reserves

FCEV fuel cell electric vehicle

GHG greenhouse gas

GW gigawatt

GWh gigawatt-hour

GWdt gigawatt-days thermal

H2A Hydrogen Analysis

HHV higher heating value

IAEA International Atomic Energy Agency

kg kilogram

kWh kilowatt-hour

LDV light-duty vehicle

LHV lower heating value

MJ megajoule

MMBtu million Btu

MMT million metric tonnes

MTU metric tonnes uranium

MW megawatt

NEA Nuclear Energy Agency

NREL National Renewable Energy Laboratory

PV photovoltaic

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v 

Quad quadrillion Btu

RAR Reasonably Assured Resources

REF Renewable Energy Futures

RFS Renewable Fuel Standard

scf standard cubic feet

TRR Technically Recoverable Resources

TWh terawatt-hour

U uranium

U3O8 uranium oxide

USGS United States Geological Survey

 

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vi 

Executive Summary

This study examines the energy resources required to produce 4–10 million metric tonnes of 

domestic, low-carbon hydrogen in order to fuel approximately 20–50 million fuel cell electric 

vehicles (FCEVs). These projected energy resource requirements are compared to current 

consumption levels, projected 2040 business as usual consumption levels, and projected 2040 

consumption levels within a carbon-constrained future for the following energy resources: coal 

(assuming carbon capture and storage), natural gas, nuclear (uranium), biomass, wind (on- and 

offshore), and solar (photovoltaics and concentrating solar power). The analysis framework 

builds upon previous analysis results estimating hydrogen production potentials and drawing 

comparisons with economy-wide resource production projections. 

In addition to incorporating updated estimates and projections for fossil and nuclear resources, 

we develop revised hydrogen production potential estimates for the geographic distribution of 

three major renewable energy resources: biomass, wind, and solar. Updated hydrogen production 

potential maps are developed for each of these renewable resources, indicating production 

potential per county on both a land area and population basis. These production potentials are 

compared to an estimate of current gasoline demand at the county level to provide insight into 

spatial production potential availability with respect to anticipated demand centers where FCEVs 

would be deployed in large volumes. Total hydrogen demand in 2040 is compared to projected 

reliance on each resource type across all energy sectors, and total economic and technical 

hydrogen production potential estimates for fossil, nuclear, and renewable resources are 

compared on a conceptual basis. 

Results convey the relative pressure on the absolute availability and the spatial availability of 

various resources resulting from either modest or widespread FCEV adoption by 2040. Although 

this analysis does not account for the economics of hydrogen production and delivery, results 

suggest that ample domestic, low-carbon energy resources are available in terms of technical 

production potential and the spatial proximity of adequate resources to future demand centers.

This report is available at no cost from the 

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at www.nrel.gov/publications.
vii 

Table of Contents

List of Figures .......................................................................................................................................... viii

List of Tables .............................................................................................................................................. ix

Introduction ................................................................................................................................................. 1

Energy Resources and Hydrogen Production Potentials....................................................................... 3

Estimates for Fossil Fuel and Nuclear Resources .................................................................................. 8

Coal Resources.............................................................................................................................. 8

Natural Gas Resources.................................................................................................................. 9

Uranium Resources..................................................................................................................... 12

Estimates for Renewable Resources..................................................................................................... 14

Biomass Resources...................................................................................................................... 15

Wind Resources........................................................................................................................... 16

Solar Resources........................................................................................................................... 16

Combined Renewable Hydrogen Production Potential............................................................... 25

Water Resource Restrictions....................................................................................................... 25

Hydrogen Production Potential Summary............................................................................................ 31

Hydrogen Production Requirements for Future Demand Scenarios .................................................. 33

Conceptual Comparison of Fixed and Flow Energy Potential Estimates............................................. 39

Conclusions............................................................................................................................................... 42

References................................................................................................................................................. 43

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viii 

List of Figures

Figure 1. Energy resource potential levels.................................................................................................... 7

Figure 2. Domestic fossil and uranium energy resource potentials.............................................................. 8

Figure 3. Geographic distribution of conventional natural gas resources................................................... 10

Figure 4. Geographic distribution of continuous natural gas resources...................................................... 11

Figure 5. Major U.S. uranium reserves....................................................................................................... 13

Figure 6. Hydrogen production potential from solid biomass resources, by county land area ................... 20

Figure 7. Hydrogen production potential from gaseous biomass resources, by county land area .............. 21

Figure 8. Hydrogen production potential from onshore wind resources, by county land area ................... 22

Figure 9. Hydrogen production potential from offshore wind resources, by county land area................... 23

Figure 10. Hydrogen production potential from utility-scale PV resources, by county land area.............. 24

Figure 11. Hydrogen production potential from renewable resources, by county land area ...................... 26

Figure 12. Hydrogen production potential from dominant renewable resources, by county land area ...... 27

Figure 13. Population of the United States, by county ............................................................................... 28

Figure 14. U.S. gasoline consumption by county, 2010 ............................................................................. 29

Figure 15. Renewable hydrogen production potential relative to gasoline consumption, by county ......... 30

Figure 16. Adoption curve indicating the ramp-up to a hydrogen demand resulting from 100 or 20 million 

FCEVs deployed by 2040 ...................................................................................................... 33

Figure 17. Current and projected Reference Case (a) and Greenhouse Gas $25 scenario (b) energy 

consumption across all energy sectors by resource type, with requirements for 50 million 

FCEVs.................................................................................................................................... 38

Figure 18. Approximate hydrogen production potentials for each resource............................................... 41

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ix 

List of Tables

Table 1. Description of Coal, Nuclear, and Natural Gas Reserves............................................................... 5

Table 2. Data Information and Sources for Renewable Energy Resource Estimates................................. 17

Table 3. Amount of Renewable and Non-renewable Resources Required to Produce 1 kg of Hydrogen and 

Production Efficiencies.......................................................................................................... 19

Table 4. Conversion Assumptions.............................................................................................................. 32

Table 5. Availability, Current Consumption, and Projected Consumption for Fossil and Nuclear 

Resources............................................................................................................................... 35

Table 6. Availability, Current Consumption, and Projected Consumption for Biomass, Wind and Solar 

Resources............................................................................................................................... 36

Table 7. Technical Resource Potential for Finite and Renewable Resources............................................. 39

This report is available at no cost from the 

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at www.nrel.gov/publications.
1 

Introduction

An abundant supply of domestic low-carbon energy resources will be required to reduce future 

economic and environmental impacts due to energy insecurity and climate change. U.S. oil 

dependence incurs both direct economic costs upon the economy and indirect costs associated 

with military expenditures (Delucchi and Murphy 2008; Leiby 2012; Greene 2012), and the 

potential societal costs of climate change impacts are large compared to the projected costs of 

abatement (Stern 2010). Various studies have examined the potential to deploy low-carbon 

advanced vehicles and fuels in order to meet long-term greenhouse gas (GHG) reduction goals 

(McCollum and Yang 2009; Melaina and Webster 2011; NRC 2013). The use of domestic lowcarbon hydrogen in fuel cell electric vehicles (FCEVs) is a promising technological option for 

reducing both GHG emissions and reliance on imported oil. 

A successful, long-term strategy for FCEV deployment is to use hydrogen produced from a 

diverse array of low-carbon domestic energy resources, such as coal (with carbon capture and 

storage [CCS]), nuclear, biomass, wind, and solar energy. Natural gas is also addressed as a 

transitional energy feedstock and as a domestic, low-carbon option if converted to hydrogen in a 

large central plant with CCS. This study builds upon previous estimates made by Milbrandt and 

Mann for hydrogen production potentials for wind, solar, and biomass (2007) and for coal, 

natural gas, nuclear, and hydro power (2009). These studies produced maps indicating resource 

potential location and intensity at a county level. While the geographic location of fossil, nuclear, 

and hydro power resources has not changed considerably since the Milbrandt and Mann study 

(2009), updated maps are presented here for biomass, wind, and solar hydrogen production 

potentials. These renewable resource potentials are based upon an updated and consistent 

calculation of technical potential, part of the National Renewable Energy Laboratory’s (NREL’s) 

ongoing work to compare the technical potential consistently across renewable energy 

technologies (Lopez et al. 2012). In addition, fossil and uranium resource data are updated and 

conversion efficiencies from the updated Hydrogen Analysis (H2A) production case studies are 

incorporated (DOE 2012). This study also includes a more consistent treatment of economic and 

technical resource estimates, though additional work is needed to provide a unifying framework 

for energy resource estimates (cf., Mercure and Salas 2012). 

The first section of the report reviews energy resource estimates and classification systems for 

each of the resource types. In most cases, resource data are taken from the Energy Information 

Administration’s (EIA) 2011 Annual Energy Review (AER) report (EIA 2012c). Production 

efficiencies are incorporated to develop production potentials for each resource type and 

renewable potentials are examined spatially through a series of maps. The second section of the 

report examines two hypothetical future demand scenarios, requiring either 4 or 10 million 

metric tonnes (MMT) of hydrogen to be produced by 2040 to support a fleet of FCEVs. 

Resource requirements to meet these demand levels are compared to current resource 

consumption levels, as well as projected consumption levels in 2040, relying upon projections 

from EIA’s Annual Energy Outlook (AEO) 2013 Early Release results. Comparisons are made to 

both the AEO Reference Case and to an AEO side case that tends to switch to lower carbon 

energy resources in response to a carbon price signal. In addition to exploring economic potential 

estimates, total technical potential estimates are compared between the “stock” energy resources 

(fossil and uranium) and the “flow” energy resources (biomass, wind, and solar). These 

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2 

comparisons provide some insight into the potential contribution of different low-carbon energy 

resources to future demand for hydrogen from FCEVs. 

In summary, this hydrogen production resource assessment addresses the following objectives:

• Estimate total technical and economic hydrogen production potentials for multiple lowcarbon energy resources 

• Determine the geographic availability of renewable hydrogen on a land-area and perperson basis, and compare these results to the spatial distribution of current gasoline 

consumption on a per-county basis 

• Estimate hydrogen production requirements for hypothetical future demand scenarios 

• Estimate the quantity of low-carbon energy resources required to meet hypothetical 

future demand levels, and compare those requirements to the projected future 

consumption of each resource. 

This report is available at no cost from the 

National Renewable Energy Laboratory (NREL) 

at www.nrel.gov/publications.
3 

Energy Resources and Hydrogen Production 

Potentials

Energy resources are quantified according to resource-specific classifications and metrics. The 

classification schemes used for mineral resources typically take into account the economic 

feasibility and geologic certainty of a particular resource (McKelvey 1967; United States 

Geological Survey [USGS] 1980). In general, the term resource refers to naturally occurring 

material that could feasibly be extracted economically, and the terms reserves or proved reserves

are more restrictive, referring to a subset of total resources that can be recovered with reasonable 

certainty under existing economic and operating conditions (USGS 1980; BP 2012). However, 

definitions vary significantly. For example, U.S. coal resource estimates are not associated with 

an economic component and reflect the amount of coal that exists without reference to the 

economic feasibility of mining. In contrast, uranium resources are defined according to specific 

production cost thresholds. As discussed by Rogner (2000) and others (WEC 2010; Mercure and 

Salas 2012), the categorization and estimation of energy resources is based upon a dynamic 

relationship between technological advances and changing market conditions. Rogner (2000) 

summarizes the relationship between resources and reserves as being heavily dependent upon 

technological developments: “technological improvements are continuously pushing resources 

into the reserve category by advancing knowledge and lowering extraction costs” (p. 138). 

This study draws upon updated resource data to estimate hydrogen production potentials, and 

compares projections of future hydrogen demand to projected future consumption of the 

following energy resources: 

• Natural gas

• Coal

• Nuclear (uranium)

• Biomass

• Wind

• Solar. 

The distinctions between technological and economic resource potentials are particularly 

important for interpreting estimates of hydrogen production potential. Though hydrogen FCEVs 

may prove to be competitive under business-as-usual (BAU) policy and economic conditions, 

some policy support will likely be needed for early market growth, and greater market share will 

likely be attained under future market conditions where the cost of carbon or criteria emissions

are internalized as market signals or regulatory requirements (NRC 2013). Therefore, the same 

future market conditions that would prove favorable to FCEVs will likely also be favorable for 

the economic extraction of low-carbon energy resources. Estimating energy resource potentials 

involves many uncertainties, and resource potential estimates under BAU conditions are 

generally better understood than those projected under unique economic or policy-driven market 

conditions. 

Technically Recoverable Resources (TRR) for crude oil and natural gas are defined by EIA as 

resources that are “producible using current technology without reference to the economic 

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4 

viability thereof” (EIA 2013b, Table 4.1). TRR are calculated as the sum of Proved Reserves and 

Unproved Resources, where Proved Reserves have a higher degree of economic feasibility and 

are quantified with greater precision due to more reliable technical data. As a reference, proved 

natural gas reserves are defined as “those volumes of natural gas that geologic and engineering 

data demonstrate with reasonable certainty to be recoverable in future years from known 

reservoirs under existing economic and operating conditions” (EIA 2012b) (see Table 1). As 

indicated in Figure 1, these general categories are adhered to in the present report, to the degree 

possible, by describing technical and economic potentials for hydrogen production from different 

energy resources. For economic potentials, we refer to estimates of Proved Reserves for natural 

gas, Recoverable Reserves at Producing Mines for coal, Reasonably Assured Resources (RAR) 

recoverable at $50/pound of uranium oxide (lb U3O8) ($130/kilogram of uranium [kg U]) for 

uranium, and high demand results from the Renewable Energy Futures study (NREL 2012) for 

biomass, wind, and solar resources. For technical potentials, we refer to estimates of Unproved 

Resources for natural gas, Demonstrated Reserve Base estimates for coal, RAR recoverable at 

$100/lb U3O8 ($260/kg U) for uranium, and a consistent set of technical potential estimates for 

biomass, wind, and solar resources (Lopez et al. 2012). 

These energy resource classifications are only roughly consistent across the two general 

categories of technical and economic potential proposed in Figure 1. Each classification category 

is specific to the unique characteristics, available data, or assessment assumptions of a particular 

energy resource. For example, classification systems are not necessarily consistent in 

determining when occurrences of a resource move from the theoretical potential category into 

the technical potential category, and there are variations and gradations in how different 

estimates might move from technical into economic potential categories. Figure 1 is a simple, 

high-level view of multiple resource classification types, and does not include, for example, the 

dimension of geologic certainty used to classify fossil and nuclear resources. Efforts to develop 

more consistent analytical representations of economic and technical potentials for multiple 

resource types are ongoing (cf., Mercure and Sala 2012). An integrated economic assessment of 

how future market and policy conditions that accelerate the adoption of FCEVs would also 

change the economic potential of different energy resources is beyond the scope of this study. 

The sections below review technical and economic potentials for each resource type, as well as 

the hydrogen production potentials associated with each resource type. Though the uncertainties 

associated with the various resource estimates are not discussed in detail, and the inconsistencies 

between different types of resource estimates and classifications are not resolved, some 

comparisons are made between technical and economic hydrogen production potential estimates

to provide perspective on the total low-carbon hydrogen production potential. These comparisons 

are made at a high level, and are only intended to provide context and insight into general trends 

for the overall discussion of hydrogen production potentials. Characterizing the economic or 

market implications of resource scarcity or availability on future hydrogen production systems or 

FCEV market dynamics, especially under a given set of policy constraints, would require both a 

more consistent representation of energy resources and extensive techno-economic and market 

analyses. 

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5 

Table 1. Description of Coal, Nuclear, and Natural Gas Reserves

Energy Resource Type Reserves Description Source

Coal Estimated Recoverable Reserves (ERR): “An estimate of coal reserves, 

based on a demonstrated reserve base, adjusted for assumed 

accessibility and recovery factors, and does not include any specific 

economic feasibility criteria.”

Demonstrated Reserve Base (DRB): “A collective term for the sum of 

coal in both measured and indicated resource categories of reliability, 

representing 100 percent of the in-place coal in those categories as of a 

certain date. Includes beds of bituminous coal and anthracite 28 or more 

inches thick and beds of subbituminous coal 60 or more inches thick 

that can occur at depths of as much as 1,000 feet. Includes beds of 

lignite 60 or more inches thick that can be surface mined. Includes also 

thinner and/or deeper beds that currently are being mined or for which 

there is evidence that they could be mined commercially at a given time. 

Represents that portion of the identified coal resource from which 

reserves are calculated.”

Estimated Recoverable 

Reserves description from EIA 

online glossary: 

http://www.eia.gov/tools/

glossary/?id=coal 

Demonstrated Reserve Base 

description from AER 2011

Glossary, page 353 (EIA 

2012c). 

Natural Gas EIA provides the following description of natural gas Proven Reserves: 

“Those volumes of natural gas that geologic and engineering data 

demonstrate with reasonable certainty to be recoverable in future years 

from known reservoirs under existing economic and operating 

conditions.”

Undiscovered Technically Recoverable Resources are estimated for oil 

and gas by USGS, which completed the last comprehensive National 

Assessment of oil and natural gas resources in 1995 and has made 

updates for high-priority basins since 2000. Recent updates to the 

classification system since the 1995 assessment are reviewed by 

Schmoker and Klett (2005), and include three key changes: (1) level of 

assessment switched from individual plays to a more comprehensive 

and unifying framework of assessment units, (2) switch from assessing 

all technically recoverable resources to a more restrictive condition to 

include technically recoverable resources with the potential to be added 

to reserves, and (3) change from an unlimited timeline to a 30-year 

timeframe for when the undiscovered resources might be realized. 

Natural Gas Proved Reserves 

description from EIA (2012b). 

Undiscovered Technically 

Recoverable Resources for 

natural gas are reported 

through the National 

Assessment website (USGS

2012) 

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6 

Energy Resource Type Reserves Description Source

Uranium “RAR: Uranium that occurs in known mineral deposits of such size, 

grade, and configuration that it could be recovered within the given 

production cost ranges, with currently proven mining and processing 

technology. Estimates of tonnage and grade are based on specific 

sample data and measurements of the deposits and on knowledge of 

deposit characteristics. Note: RAR corresponds to DOE’s uranium 

reserves category.”

Uranium reserves are reported with reference to costs below either $50 

or $100 per pound of uranium oxide, where EIA’s “forward costs” are 

defined as follows:

“Forward costs include the costs for power and fuel, labor, materials, 

insurance, severance and ad valorem taxes, and applicable 

administrative costs. Past capital costs are considered ‘sunk’ costs and 

mining of the individual deposits may or may not return such costs to 

investors. Sunk costs for such items as exploration and land acquisition 

are excluded as are the costs for income taxes, profit, and the cost of 

money. The forward costs used to estimate U.S. uranium ore reserves 

are independent of the price at which uranium produced from the 

estimated reserves might be sold in the commercial market. Reserves 

values in forward-cost categories are cumulative; that is, the quantity at 

each level of forward cost includes all reserves at the lower cost in that 

category.”

RAR description is from the 

AER 2011 Glossary (EIA 

2012c). 

Forward costs description from 

AER 2011, Table 4.10 (EIA 

2012c). 

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7 

 

 

 

Figure 1. Energy resource potential levels

Source: NREL

Notes: Technical potential for coal is the Demonstrated Reserve Base (DRB) minus Estimated Recoverable Reserves (ERR). Economic and technical potential 

estimates for uranium are RAR estimates at two forward-cost thresholds. Total undiscovered uranium resources include prognosticated and speculative resources. 

Energy Resource Type .

Coal Natural Gas Uranium Renewable

Estimated 

Recoverable 

Reserves (ERR)

Proved 

Reserves

RAR Estimates 

at <$50/lb U3O8

Projections of 

Supply in a 

High Demand 

Scenario

Demonstrated 

Reserve Base 

(DRB) 

Unproved 

Resources

RAR Estimates 

at <$100/lb

U3O8

Current 

Technical 

Potential

Other 

Occurrences

Other 

Occurrences

Total 

Undiscovered 

Resources

Higher 

Technical 

Performance

. 

Theoretical 

Potential

Technical

Potential

Economic

Potential

Increasing Economic Potential

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8 

Estimates for Fossil Fuel and Nuclear Resources

Economic and technical potential estimates for coal, natural gas, and uranium are summarized on 

an equivalent thermal energy basis (quadrillion British thermal units [Btu] [quads], higher 

heating value [HHV]) in Figure 2. As indicated, proved natural gas reserves have been increasing 

in recent years, uranium reserves are presented at two distinct cost levels, and both estimated 

recoverable and total demonstrated coal reserves have been declining slowly over time. Again, 

these classification systems are not necessarily consistent across resource types, but are used here 

as general estimates for economic and technical energy resource potentials. Additional 

information on each of these potentials, and conversions to determine hydrogen production 

potentials, is provided in the sections below. Descriptions of fossil and uranium reserve and 

resource categories are summarized in Table 1. 

Figure 2. Domestic fossil and uranium energy resource potentials

Sources: EIA 2012c, Table 4.10; EIA 2012d, Table 15; EIA 2012c, Table 4.2.

Coal Resources

EIA reports estimates for the coal Demonstrated Reserve Base (DRB), which is “a collective 

term for the sum of coal in both measured and indicated resource categories of reliability, 

representing 100 percent of the in-place coal in those categories as of a certain date” (EIA 2013b, 

p. 353). The annual coal report provides estimates of Recoverable Reserves at Producing Mines, 

the most economic and probable subset of total coal reserves, as well as Estimated Recoverable 

Reserves (ERR) (EIA 2012d). Table 1 provides descriptions of each of these coal resource 

classifications. Our estimates for hydrogen production potential rely upon the ERR 259 billion 

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9 

short tons for coal’s economic potential (Figure 1), following comparisons between coal and 

natural gas proved reserves presented elsewhere (Rogner 1997; WEC 2010). By comparison, 

coal resources reported in the DRB are nearly twice as large, at 483 billion short tons (EIA 

2012d). The difference of 224 billion short tons is our estimate for coal technical potential (see 

Figure 1). Wyoming, Montana, and Illinois account for nearly 60% of total coal reported as ERR

and in the DRB (EIA 2012d). To convert to thermal energy equivalents, we use EIA’s reported 

HHV of 20.142 million Btu (MMBtu)/short ton for coal produced in 2011 (EIA 2013c). This is 

similar to the weighted average heating value for the different coal types reported in the DRB 

(9% lignite, 37% subbituminous, 53% bituminous, and 2% anthracite). The result is a combined 

technical and economic potential of approximately 9,700 quads for the DRB in 2011 (see Figure 

2). 

Natural Gas Resources

Proved reserves for dry natural gas are reported by EIA as 304.6 trillion cubic feet in 2010 (EIA 

2012c, Table 4.2). The breakdown provided in the previous year, 2009, indicates that reserves of

tight gas, shale gas, and coalbed methane accounted for 61% of total proved reserves (EIA 

2012c, Table 4.1), with the remainder from conventionally reservoired fields. Figure 2 shows the 

historical changes in proved natural gas reserve estimates over time. Estimates for natural gas 

shale reserves have grown rapidly in recent years, increasing by a factor of 4 between 2008 and 

2010. Estimates for unproved natural gas, or the “technical potential” category in Figure 1, are 

reported as 1,930 trillion cubic feet (Tcf) in 2009 (EIA 2012c, Table 4.2). Of this total, 25% is 

shale gas, 22% is tight gas, 14% is offshore of the lower 48 states, and 14% is on- and offshore 

in Alaska (EIA 2012a). These EIA estimates depend, in part, on data from the USGS. Oil and 

natural gas resource classification systems have been modified and updated over time, with 

recent changes for natural gas summarized by Schmoker and Klett (2005) and described in Table 

1. 

Adding Proved Reserves to Unproved Reserves, the estimate for total technical and economic 

potential for natural gas resources is approximately 2,200 trillion standard cubic feet (scf), or 

about 2,300 quads on an HHV basis (see Figure 2). To convert to thermal energy equivalent, we 

use EIA’s reported HHV of 1,025 Btu/scf for dry natural gas produced in 2009 (EIA 2012c, 

Table A4). The geographic distribution of different types of natural gas resources is presented by 

USGS in a series of maps (USGS 2012). Two of these maps, for conventional and continuous 

(coalbed gas, shale gas, and tight gas) natural gas resources, are shown in Figure 3 and Figure 4. 

As indicated, most conventional resources are in the Gulf Coast and Alaska, while most 

continuous resources are distributed across the Mountain States, throughout the Gulf Region, and 

in the Appalachian Basin. 

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Figure 3. Geographic distribution of conventional natural gas resources 

Source: USGS (2012) 

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Figure 4. Geographic distribution of continuous natural gas resources 

Source: USGS (2012) 

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Uranium Resources

EIA reports uranium reserves in units of millions of pounds of uranium oxide, and uses a 

conversion of 0.848 kg U per 1 kg U3O8. The uranium reserve quantities reported by EIA are 

equivalent to the international categorization for RAR, which is described in Table 1. The two 

prominent types of uranium reserves reported by EIA are expressed in terms of forward-costs for 

production, with cost thresholds of less than $50/lb U3O8 and less than $100 /lb U3O8. 

Components of these forward-costs are described in Table 1. The 2008 uranium reserve estimate 

from EIA is distinct from reserve estimates in previous years, and reports 539 million pounds of 

U3O8 at less than $50/lb, and 1,227 million pounds U3O8 at less than $100/lb (EIA 2013b, Table 

4.10). The international “Red Book” report also reports inferred reserves (lower geologic 

certainty) according to RAR cost categories, but not for the United States (Nuclear Energy 

Agency and International Atomic Energy Agency [NEA-IAEA] 2010). In recent years, the price 

of uranium has approached and exceeded $50/lb U3O8 (EIA 2012c, Table 9.3), but given the 

global market for uranium resources, we assume that the $100/lb cost category is a reasonable 

estimate for uranium technical potential. There are major uncertainties associated with U.S. 

uranium resource estimates, and a thorough evaluation of the U.S. uranium resource base has not 

been conducted for some time. Details on how the RAR classification systems have changed 

over time, and implications for domestic U.S. and international resource estimates, are discussed 

elsewhere (NEA-IAEA 2012; WEC 2010). For an estimate of the theoretical potential, we refer 

to the 6,793 million lb of undiscovered uranium reported by NEA-IAEA (2012, Table 1.14).

However, these estimates are also highly uncertain, and future assessment updates may result in 

significant changes (cf., Hall 2013). With the RAR estimates for each cost level noted above, the 

uranium economic potential is about 540 million lb U3O8, and the combined economic and 

technical potential is about 1,200 million lb U3O8. 

Given that uranium imports have been increasing since 1990, restricting our resource 

calculations to only U.S. uranium resources does not fully capture actual supply or market 

constraints associated with future demand growth. However, for the sake of simplicity, we 

restrict our analysis to domestic resources to mirror estimates made for the other resource types. 

As a reference for a total global technical potential estimate, the results of the recent USGS

critical analysis of world uranium resources are relevant. Hall and Coleman (2012) report an 

estimated 2.1 MMT of recoverable uranium globally. This estimate is comparable in terms of 

resource type, but more conservative than the “2011 Red Book” RAR estimate from the 

Organisation for Economic Co-operation and Development NEA-IAEA, reporting 3.45 million 

metric tonnes of uranium (tU) globally at less than $130/kg U. Including inferred resources along 

with RAR increases, the Red Book global estimate is 5.33 million tU at less than $130/kg U. Of 

this total, the U.S. contains some 4% of total RAR reserves, or 0.21 million tU (NEA-IAEA 

2012). Combined with the established trend of importing uranium, this global distribution of 

uranium resources highlights a limitation of the present report in attempting to compare only 

domestic low-carbon energy resources. 

EIA reports that the U.S. uranium reserves contained within six states—Wyoming, New Mexico, 

Arizona, Colorado, Utah, and Texas—together contain approximately 87%–90% of U.S. 

uranium reserves (EIA 2013b, Table 4.10). An EIA map depicting the general location of 

reserves is shown in Figure 5. More detailed spatial uranium and other resource data are 

available from the USGS National Uranium Resource Evaluation website (USGS 2013). NEAIAEA provides a map of global resources by country (NEA-IAEA 2012, p. 17). 

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To determine uranium resource consumption for future electricity generation, a nominal burnup 

rate of 45 gigawatt-days thermal per metric tonne of uranium (GWdt/MTU) is assumed based 

upon historical data from EIA (2004). A heat rate of 10,458 Btu/kWh (32.6% thermal efficiency) 

is assumed based upon the average heat rates reported from 1995 to 2011 (EIA 2012c, Table 

A6). The result is approximately 352,366 kWh of electricity generated per kg of U3O8. We 

assume this approximate rate of uranium use for heat and electricity generation continues into the 

future in determining hydrogen production potentials. However, future trends in uranium 

resource management are highly uncertain and contingent upon multiple technological and 

policy factors (Kazimi, Moniz, and Forsberg 2011). Therefore, projected resource demands are 

expressed in terms of nuclear electricity generation from the 2013 AEO (EIA 2013a), rather than 

assuming a conversion rate of uranium to electricity by 2040 (see Table 5). 

Figure 5. Major U.S. uranium reserves 

Source: EIA (2010) 

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Estimates for Renewable Resources

We use data from the county-level spatial analysis conducted by Lopez et al. (2012) to estimate 

the technical potential for producing hydrogen from three renewable energy resources: biomass, 

wind, and solar. A brief description of the resource analysis is provided in the sections below for 

each technology used to harness these renewable energy resources. Detailed information about 

system-specific power densities (or equivalent), capacity factors, and land-use constraints is 

provided in Lopez et al. (2012, Appendix A). The following are general descriptions of the 

renewable technical potential estimates: 

“These are technology-specific estimates of energy generation potential based on 

renewable resource availability and quality, technical system performance, 

topographic limitations, environmental, and land-use constraints only. The 

estimates do not consider (in most cases) economic or market constraints, and 

therefore do not represent a level of renewable generation that might actually be 

deployed.” 

(Lopez et al. 2012, p. iv) 

“Note that as a technical potential, rather than economic or market potential, these 

estimates do not consider availability of transmission infrastructure, costs, 

reliability or time-of-dispatch, current or future electricity loads, or relevant 

policies. Further, as this analysis does not allocate land for use by a particular 

technology, the same land area may be the basis for estimates of multiple 

technologies (i.e., non-excluded land is assumed to be available to support 

development of more than one technology). Finally, since technical potential 

estimates are based in part on technology system performance, as these 

technologies evolve, their technical potential may also change.” 

(Lopez et al. 2012, p. 2)

For economic potentials, we reference projections to 2050 for renewable electricity production 

from the Renewable Energy Futures (REF) study (NREL 2012). The REF study explores a range 

of scenarios in which renewable energy sources provide large percentages of total U.S. 

electricity, focusing on various scenarios in which 80% of generation is from renewables by 

2050. The High-Demand scenario involves assumptions resulting in an annual demand of 5,100 

terawatt-hours (TWh) by 2050, with approximately 12% from biomass, 3% from geothermal, 

10% from hydropower, 6% from concentrating solar power (CSP), 12.5% from solar 

photovoltaics (PV), 26.5% from onshore wind, and 10% from offshore wind (NREL 2012, 

Figure 3-14). The REF study examines costs and barriers to market growth, and therefore 

constitutes a techno-economic feasibility study that explores the long-term economic potential of 

renewable energy resources. The study is limited in only addressing electricity, but otherwise 

provides a consistent and technically integrated projection of relative contributions of each 

renewable resource. 

Another reference relied upon to estimate renewable energy economic potential is the market 

outcome result from the 2013 AEO Greenhouse Gas $25 scenario (EIA 2013a). In this side case, 

a price of $25 per metric ton carbon dioxide is assumed beginning in 2014, and the price 

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15 

increases at 5% per year through 2040. The results of this side case are relevant to estimating 

economic potentials and are used as a reference for projections of future hydrogen production 

requirements in the future demand scenarios discussed below. 

Assuming the REF high electricity demand results above for 2050 and the approximate 

percentages of supply by resource type, we estimate an economic potential of 1,000 TWh for 

solar and 2,000 TWh for wind (see Table 5). For biomass economic potential, we assume that the 

plateau in supply at approximately 6 quads (350 million tons) between 2020 and 2032 in the 

2013 AEO Greenhouse Gas $25 side case is a robust market outcome that would not conflict 

with the approximately 550 million tons estimated for biopower in the REF study.1 The result is 

an estimated biomass economic potential of approximately 900 million tons. This result is unique 

to this study, and represents an economic potential corresponding to a future with high demand 

for low-carbon resources and a relatively high degree of technological development. Additional 

analysis is required to better understand competition for biomass resources between the 

transportation fuel and electricity sectors (cf. Ruth et al. 2013). 

Biomass Resources

Estimates of biomass resource potential vary significantly. For this study, we assume that the 

technical potential for biomass resources falls between currently available resources 

characterized by Lopez et al. (2012) and baseline projections to 2030 from the Billion Ton Study 

Update (DOE 2011b). The current biomass technical potential reported by Lopez et al. (2012) 

includes 363.4 million bone-dry tonnes (BDT) of solid biomass and 18.8 million tons of methane 

as biogas. An HHV of 8,500 Btu/lb is applied for solid biomass, and an HHV of 24,250 Btu/lb is 

applied for biogas (Lopez et al. 2012). Details on this technical potential for biomass resources 

are provided in Lopez et al. (2012), a brief summary is provided in Table 2, and updates are 

available on the NREL Biomass Research Data and Resources website (NREL 2013). 

Converting these solid and gaseous biomass resources to hydrogen using the conversion 

efficiencies indicated in Table 3 results in approximately 31 MMT hydrogen per year. The

geographic distribution of biomass hydrogen production potential based upon currently available 

solid and gaseous biomass resources is indicated in Figures 6 and 7. The baseline scenario in the 

U.S. Billion Ton Update study, at $60 or less per dry ton, projects 1,094 million dry tons by 

2030, which is equivalent to approximately 76 MMT hydrogen per year. This upper range for 

technical potential would only be realized over time and under favorable market, policy, and land 

use conditions (DOE 2011b).

An appropriate reference for the economic potential is assumed to be biomass supply in the 2013 

AEO Greenhouse Gas $25 scenario (EIA 2013a). Total biomass consumption by 2040 is 

equivalent to about 8.0 quads (HHV), or approximately 453 million short tons of biomass on an 

energy equivalent basis, converting to approximately 31.5 MMT hydrogen per year. This is 

slightly higher than the hydrogen production potential from current biomass resources from 

Lopez et al. (2012) and significantly lower than the potential from the U.S. Billion Ton Update 

base case at $60 per dry ton. Within the Greenhouse Gas $25 scenario, the biomass consumption 

within the transportation sector is only 15% higher than consumption in the AEO Reference 

 

1 550 million BDT results from approximately 600 TWh of biopower and 1.1 megawatt-hours per BDT. Note that 

the biomass supply in the GHG $25 side case increases rapidly after 2032 as a result of success with cellulosic dropin fuels (EIA 2013a, Figure 100).

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Case.

2

 This is probably due to the carbon price signal having little effect on the transportation 

sector overall. Given that the Reference Case does not meet the Renewable Fuel Standard (RFS) 

requirement of 36 billion ethanol-equivalent gallons by 2022 (Sieminski 2013), we estimate that 

the Greenhouse Gas $25 scenario may also fall short by approximately 7 billion gallons of 

ethanol-equivalent gallons. If additional low-carbon policies were in place to increase biofuels 

use in this scenario, such that the RFS requirements were met and maintained out to 2040, 

another approximately 1.7 quads of biomass resources may be required. 

Wind Resources

The total technical potential for wind resources is estimated by Lopez et al. (2012) to be 49.8 

million GWh of generation, with 66% from onshore wind resources and 34% from offshore wind 

resources. Assuming a hydrogen production power requirement of 46 kWh per kg of hydrogen 

for water electrolysis (see Table 3), translates to a technical hydrogen production potential of 

1,100 MMT hydrogen per year. The geographic distribution of onshore and offshore wind 

resources is indicated in Figures 8 and 9. This offshore wind estimate is probably an 

overestimate, as it does not include an exhaustive set of exclusions. On the other hand, data are 

not available for some coastal areas that do not have wind data, as indicated. Additional maps 

and updated wind resource data are provided through the NREL Wind Maps website.3

 Wind 

generation in the 2013 AEO Greenhouse Gas $25 scenario is 0.616 million GWh, which results 

in an economic hydrogen production potential of about 13 MMT hydrogen per year (see Table

3). The Greenhouse Gas $25 scenario does not project any growth in the market for offshore 

wind. 

Solar Resources

The total technical potential for solar resources estimated by Lopez et al. (2012) includes 2.2 

million GWh from urban utility-scale PV systems, 280.6 million GWh from rural utility-scale 

PV systems, 0.8 million GWh from rooftop PV systems, and 116.1 GWh from CSP systems. The 

total technical potential is 400 million GWh, with 70% of the total from rural utility-scale PV 

systems. This translates to 8,700 MMT of hydrogen technical production potential (see Table 6). 

A summary of the key elements of this assessment is provided in Table 2, and a more detailed 

description can be found in Lopez at al. (2012). The geographic distribution of this solar 

potential is indicated in Figure 10, and additional information and updates can be found on the 

NREL Solar Maps website.4 By comparison, solar generation in the Greenhouse Gas $25

scenario is 313 billion kWh, with CSP contributing less than 1%, translating to an economic 

hydrogen production potential of 6.8 MMT hydrogen per year. 

 

2 At the time this report was prepared, only limited results had been made available from the 2013 AEO Early 

Release (EIA 2013a). A more detailed breakdown of biomass use within different transportation fuel types could not 

be discerned for the Greenhouse Gas $25 scenario. 3 “Dynamic Maps, GIS Data, & Analysis Tools—Wind Maps.” (2012). National Renewable Energy Laboratory: 

http://www.nrel.gov/gis/wind.html. 4 “Dynamic Maps, GIS Data, & Analysis Tools—Solar Maps.” (2012). National Renewable Energy Laboratory: 

http://www.nrel.gov/gis/solar.html.

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Table 2. Data Information and Sources for Renewable Energy Resource Estimates

Resource Type Resource Data Information Sources 

Solid Biomass and 

Biogas

Biomass and biogas data from Lopez et al. (2012) are updates to the 2005 report by Milbrandt. 

Biomass data and updates are available online (http://www.nrel.gov/gis/data_biomass.html). 

Key aspects of the biomass data are summarized below:

• Secondary mill residues, and urban wood waste, updated in 2012 

• “The data from Milbrandt (2005, updated in 2008) illustrate the biomass resources currently 

available in the United States. Subsequent revisions of this analysis could evaluate 

projected U.S. resource potential, including dedicated energy crops such as those provided 

by the recent DOE update (DOE 2011b) of the billion-ton biomass study (Perlack et al. 

2005).” (Lopez et al. 2012, p. 6) 

• It is assumed that all biomass resources are available. Competition between different 

markets (e.g., biopower, biofuels, hydrogen) has not been taken into account

• Estimates for gaseous biomass (methane emissions) are currently being updated. See the 

NREL Biomass Maps website for updates and access to data or 

maps: http://www.nrel.gov/gis/biomass.html. 

Lopez et al. (2012)

Data are available 

online:

http://www.nrel.gov/

gis/re_potential.html 

Onshore Wind • Defined at 80 m above ground

• Annual average gross capacity factor of 30% (net capacity factor of 25.5%)

• The analysis assumed “typical utility-scale wind turbine power curves,” and excluded 

environmental and conflicting land-use areas or areas with slopes greater than 20% 

• “AWS Truepower modeled the wind resource data using its Mesomap process to produce 

estimates at a 200-m horizontal spatial resolution. These resource estimates were 

processed to eliminate areas unlikely to be developed, such as urban areas, federally 

protected lands, and onshore water features...We estimate annual generation by assuming 

a power density of 5 MW/km2 (DOE EERE 2008) and 15% energy losses to calculate net 

capacity factor” (Lopez et al. 2012, p. 5). 

Lopez et al. (2012)

Data are available 

online:

http://www.nrel.gov/

gis/re_potential.html

Offshore Wind • Defined at 90 m above ground

• Florida and Alaska data not available at time of publication (omitted from totals)

• Exclusions: shipping lanes, marine sanctuaries, and others 

• Generation estimates assume a power density of 5 MW/km2

, and develop capacity factors 

as a function of local or regional conditions

Lopez et al. (2012)

Data are available 

online:

http://www.nrel.gov/

gis/re_potential.html

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Resource Type Resource Data Information Sources 

• Other land exclusions and technical assumptions are detailed in Lopez et al. (2012).

Urban and Rural Solar 

PV

• Urban PV systems are assumed to be located on suitable land areas within urban area 

boundaries, and rural PV systems are assumed to be located on suitable land areas 

outside of urban area boundaries 

• Urban areas smaller than 18,000 m2 are excluded

• Areas with slopes greater than 3% are excluded

• Annual capacity factors are taken from the National Solar Radiation Database

• Other land exclusions and technical assumptions are detailed in Lopez et al. (2012). 

Lopez et al. (2012)

Data are available 

online:

http://www.nrel.gov/

gis/re_potential.html

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Table 3. Amount of Renewable and Non-renewable Resources Required to Produce 1 kg of Hydrogen and Production Efficiencies

Resource Conversion Pathway Amount to Produce 1 kg Hydrogen a

Production 

Efficiency b 

(Eout/Ein, LHV)

Natural gas Steam methane 

reforming 167.5 scf 165 MJ 73.1%

Coal Coal gasification with 

CCS 9.8 kg 271 MJ 44.3%

Nuclear 

(uranium)

High-temperature 

electrolysis 6.72×10-5 kg U 260 MJ 46.0%

Nuclear

(uranium) Thermochemical 7.03×10-5 kg U 273 MJ 44.0%

Biomass Biomass gasification 13.0 kg bone dry 

biomass

242 MJ 48.3%

Wind power Electrolysis 46 kWh 166 MJ 72.6%

Solar power Electrolysis 46 kWh 166 MJ 72.6%

MJ = megajoule

a Values are derived from H2A Future Central Case Studies for each resource type and from the central electrolysis case study for wind and solar. Efficiencies 

indicated are for “hydrogen energy out” divided by “resource energy in,” and do not account for any additional input feedstock consumption or electricity byproduct 

credits. Efficiency definitions are distinct in that resource “energy in” is in different forms, as noted in the column indicating MJ of resource required. The 167.5 scf 

per kg for steam methane reforming is derived from the future central steam methane reforming case study, 9.8 kg of coal is from the future central coal 

gasification case study (coal use is equivalent between the with and without CCS case studies), and 13.0 kg bone dry biomass is from the future central biomass 

gasification case study. Heat content of coal is 27.685 MJ/kg coal, and it is associated with natural gas with an LHV of 930 Btu/scf. Uranium consumption for the 

nuclear high-temperature electrolysis and thermochemical production pathways are described above. The H2A case studies are available from the DOE H2A 

website: http://www.hydrogen.energy.gov/h2a_prod_studies.html. b Production efficiency is defined as the energy of the hydrogen out of the production process (on a LHV basis) divided by the sum of the energy into the process 

from the feedstock. Production efficiencies indicated for wind and solar are based on electrical energy input (46 kWh) and nuclear efficiencies are on a heat input 

basis.

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Figure 6. Hydrogen production potential from solid biomass resources, by county land area

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Figure 7. Hydrogen production potential from gaseous biomass resources, by county land area

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Figure 8. Hydrogen production potential from onshore wind resources, by county land area

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23 

Figure 9. Hydrogen production potential from offshore wind resources, by county land area

This analysis represents potential generation from 

offshore wind turbines at 90 m height and a power 

density of 5 MW/km2. Offshore resource data 

extend 50 nautical miles from shore. Alaska and 

most of Florida were not included due to limited 

data.

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Figure 10. Hydrogen production potential from utility-scale PV resources, by county land area

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Combined Renewable Hydrogen Production Potential

The renewable hydrogen production potential from biomass, wind, and solar is depicted in terms 

of total kg per county, normalized by county area, in Figure 11. When compared to Figure 10, 

the potential intensity patterns reveal that solar potential tends to dominate over biomass and 

wind. Figure 12 provides the same data and indicates color coding for the dominant renewable 

potential in each county. Only a small handful of counties are not dominated by solar, with 

biomass dominating in parts of Appalachia, and either wind or biomass dominating a small 

number of counties scattered across Midwestern, Mountain, and Northwestern regions. 

Total renewable production potential can also be examined with respect to the spatial distribution 

of population and gasoline consumption. The 2010 population by county is indicated in Figure 

13. Gasoline demand data at the state level are allocated by population, and shown in terms of 

total gallons per county in 2010 in Figure 14. This distribution is nearly identical to the relative 

distribution of population, but it proves insightful when used as the basis for renewable hydrogen 

production potential. The energy basis ratio of renewable hydrogen production potential and 

gasoline consumption is indicated by county in Figure 15. Higher ratios are indicated in low 

population counties, and counties where gasoline use exceeds the hydrogen production potential 

are prevalent across Appalachia and near major urban areas. Most major urban areas are 

relatively close to counties where the renewable hydrogen production potential is 1–5 times 

greater than gasoline consumption. 

Water Resource Restrictions

As discussed in Milbrandt and Mann (2009), regional water availability may prove to be a 

limiting factor for the hydrogen production potential from fossil, nuclear, or renewable energy 

resources. As indicated in Figure 11, significant renewable hydrogen production potential exists 

in the northern and southern Midwest states, but these regions, especially the southern states, 

have significant drought and water availability issues. The potential influence of new 

transportation fuels on water resources is complex, and has been examined in a number of recent 

studies (Harto et al. 2010; King et al. 2010). Future insights will be attained from assessments 

that adopt a life-cycle framework, account for overall impacts on water resource stress rather 

than just withdrawals, and include tradeoffs among multiple transportation fuel options (cf. 

Scown et al. 2011). Water use for the electricity sector will also change in a low-carbon future 

supportive of alternative transportation fuels (Clemmer at al. 2013). A useful and integrated 

assessment of the impacts of future alternative fuel systems on water resources would need to 

take into account a wide range of uncertain and interrelated factors, and would need to explicitly 

account for various decision-making processes related to water resource management. 

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Figure 11. Hydrogen production potential from renewable resources, by county land area

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Figure 12. Hydrogen production potential from dominant renewable resources, by county land area

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Figure 13. Population of the United States, by county

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Figure 14. U.S. gasoline consumption by county, 2010 

Gasoline consumption data at the state level are from EIA’s State Energy Data System (SEDS) and are allocated to counties on a population basis.

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Figure 15. Renewable hydrogen production potential relative to gasoline consumption, by county 

Gasoline demand at the state level is allocated to counties on a population basis.

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Hydrogen Production Potential Summary

Table 3 summarizes energy inputs required to produce 1 kg of hydrogen from each resource. 

Conversion pathways and production efficiencies, on a lower heating value (LHV) basis, are 

shown for each resource and are taken from the H2A future case studies (DOE 2012). Key 

conversion factors are indicated in Table 4. Natural gas is converted through central steam 

methane reforming, the most prevalent pathway for producing hydrogen at petroleum refineries 

today, and coal and biomass are converted by way of gasification. The coal gasification pathway 

assumes CCS, though this pathway has essentially the same coal consumption per kilogram

hydrogen produced as the non-CCS pathway. Additional energy feedstock consumption and 

byproduct electricity credits are not included in the energy efficiencies indicated in Table 3. 

Nuclear production efficiencies are described above. Wind and solar resources are shown as 

producing hydrogen by way of central electrolysis, with the efficiency of 46 kWh per kg 

hydrogen from the future H2A case study. Researchers are currently investigating more direct 

means of converting solar energy into hydrogen (Turner et al. 2008), but these pathways are in 

the relatively early phases of development and projected performance for future central 

electrolysis systems is an appropriate baseline for the present analysis. Ramsden et al. (2009) 

have reviewed hydrogen production costs and conversion efficiencies for multiple pathways 

using the H2A production model. 

Hydrogen production potential estimates for the two nuclear pathways, high temperature 

electrolysis and thermochemical, include assumptions about uranium use that are not included in 

the H2A case studies. For high-temperature electrolysis, we assume the same nominal burnup 

rate of 45 GWdt/MTU, as well as the estimate from O’Brien et al. (2010) that a 600 MW-thermal

plant can produce 78×106

 scf/day of hydrogen, and therefore has a conversion efficiency of 46% 

for heat to hydrogen (LHV). This assumes a very high temperature reactor, with helium coolant 

exiting the reactor and entering a Brayton power cycle at about 900°C. These assumptions result 

in a nominal use rate of 6.72×10-5 kg U/ kg hydrogen. This value is used to determine uranium 

resource requirements for the high-temperature electrolysis production pathway. 

For the future thermochemical production pathway, we again assume a nominal burnup rate of 

45 GWdt/MTU, and rely upon the estimate from Brown et al. (2003) that a high temperature 

nuclear reactor (~950°C outlet temperature) powering a sulfur-iodine (S-I) thermochemical cycle 

could achieve a 44% thermal efficiency (LHV) in producing hydrogen. This efficiency and 

burnup rate result in a uranium use rate of 7.03×10-5 kg U/ kg hydrogen. 

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Table 4. Conversion Assumptions

Metric Value Units Source

Biomass

Required biomass 13.0 kg biomass/kg 

hydrogen H2A Future Case Study

Biomass energy content 18.61 MJ/kg biomass (LHV)

H2A Conversion Factor, 

(Biomass MYPP 

Feedstock)

Coal 

Required coal (future 

coal with CCS) 12.383 kg coal/kg hydrogen

H2A Future Case Study 

(adapted to coal heat 

content indicated below)

Coal required for 50% by 

2040 98.0 MMT Calculated

Coal energy content 20.75

MMBtu per metric tonne 

(LHV) Comparable to 

EIA HHV of 19.85 

MMBtu/tonne)

2013 AEO (EIA 2013a)

Natural gas 

Required natural gas 156,000 Btu natural gas/kg 

hydrogen H2A Future Case Study

Gas Btu content 1,024 Btu per scf (HHV) 2013 AEO (EIA 2013a)

Wind Power

Required wind 

electrolysis electricity 46.0 kWh/kg hydrogen H2A Future Case Study

Solar Power

Required solar 

electrolysis electricity 46.0 kWh/kg hydrogen H2A Future Case Study

Nuclear Power

High temperature 

electrolysis 46.2% Thermal conversion H2A Future Case Study

Thermochemical 44.0% Thermal conversion Brown et al. (2003)

Uranium use (high 

temperature electrolysis) 6.72*10-5 kg uranium per kg hydrogen O’Brien et al. (2009)

Uranium use 

(thermochemical, 950°C) 7.03*10-5 kg uranium per kg hydrogen Brown et al. (2003)

Note: heating values or conversions unique to a particular publication were used for some calculations. 

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Hydrogen Production Requirements for Future 

Demand Scenarios 

Two hypothetical future demand scenarios have been developed to examine a range of energy 

resource requirements in 2040. The Hydrogen Success scenario requires 20 MMT of hydrogen 

per year by 2040, representing the amount of hydrogen needed to fuel approximately 100 million 

light-duty FCEVs. Figure 16 indicates an S-shaped ramp-up in demand from 2010 to 2040 as 

FCEV market share grows and eventually saturates. A Niche Market demand scenario is also 

shown, requiring 4 MMT of hydrogen per year by 2040, representing the amount of hydrogen 

needed to fuel approximately 20 million FCEVs. Both demand scenarios are a simplified 

representation of light-duty vehicle (LDV) market growth and vehicle stock growth dynamics, 

with both assuming that the average FCEV on the road in 2040 travels 12,000 miles per year and 

has an average on-road fuel efficiency of 60 miles per kg of hydrogen. Other market growth 

patterns could result in similar levels of demand by 2040.5 With the 2013 AEO Reference Case

projection of 284 million LDVs by 2040 (EIA 2013a), 100 million and 20 million FCEVs would 

be 35% and 7% of total LDVs, respectively. More fully developed scenarios, with comparable 

FCEV market share growth as the Hydrogen Success scenario and unique estimates of energy 

resource requirements, are described elsewhere (Greene et al. 2008; NRC 2008; Ogden, Yang, 

and Parker 2011; O’Brien 2012; NRC 2013). 

Figure 16. Adoption curve indicating the ramp-up to a hydrogen demand resulting from 100 or 20 

million FCEVs deployed by 2040

Given these two demand scenarios, we estimate how much of any single low-carbon energy 

resource would be required by 2040 to supply 50% of the total hydrogen demand projected in the 

Hydrogen Success scenario (10 MMT, as shown in Figure 16), or 100% of total demand in the 

Niche Market scenario (4 MMT). The Niche Market scenario is referenced only occasionally 

 

5 Analytically consistent estimates of LDV fleet dynamics and future fuel demand can be generated using vehicle 

stock models that account for market share, vehicle vintaging, and reduction in vehicle miles traveled per year for 

older vehicles. Examples include the Scenario Evaluation and Regionalization Analysis (SERA) stock sub-model 

(OpenEI 2012), which is based on the VISION model (Ward 2008).

Hydrogen 

Success

Niche Market

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34 

below, while most of the focus is on resource consumption for the Hydrogen Success scenario. 

We do not attempt to estimate a mix of production sources in 2040. Instead, we estimate 

requirements for any single resource to provide these two demand levels. The resulting estimates

provide a context for discussing the potential implications of future FCEV fuel demand for 

resource constraints or market dynamics.

Natural gas is more carbon intensive than the other five resource types assessed, but it is 

considered here as an important transition energy resource to support growing markets as a lowcarbon hydrogen infrastructure develops over time. Central natural gas production with CCS is 

also a technological option. This analysis is limited to plant-gate hydrogen production potential 

only, so storage and delivery pathway efficiencies are not taken into account. The efficiencies of 

delivery pathways will vary regionally and between resource types, but these are best analyzed 

within a spatially detailed and dynamic cost-optimization framework and are not considered in 

this study. 

Table 5 shows fossil and nuclear resource availability, consumption in 2012, consumption by 

2040 under BAU and carbon-constrained market conditions, and the amount of resource needed 

to produce 4 or 10 MMT of hydrogen. Table 6 shows the same metrics for biomass, wind, and 

solar energy resources. In both tables, resource availability is shown as the economic potential

and as the total TRR. Values are indicated for both the 2013 AEO Reference Case and the 

Greenhouse Gas $25 scenarios (EIA 2013a), where the latter involves imposition of a $25/ton 

carbon tax. Resource requirements to produce 10 MMT hydrogen for 50 million FCEVs and 4 

MMT for 20 million FCEVs are also indicated. Values in the final four rows of each table are the 

percent increase in projected 2040 resource consumption as a result of producing 4 or 10 MMT 

of hydrogen for both the Reference Case and Greenhouse Gas $25 scenarios, calculated using 

the following equation: 

(Projected consumption + Requirement for FCEV demand) / Projected consumption 

These results build upon previous estimates reported in Appendix B of the U.S. DOE Hydrogen 

and Fuel Cells Program Plan (DOE 2011a). Significant differences include resource availability 

estimates being reported as both economic potential and TRR (sum of economic and technical 

potentials), a comparison with projections to 2040 from both a BAU and carbon-constrained 

scenario (2013 AEO Reference Case and Greenhouse Gas $25 scenario), and projected 

consumption to produce hydrogen reported for two demand levels (4 and 10 MMT hydrogen). In 

addition, wind and solar potentials are based upon more consistent estimates: economic potential 

values are based upon REF Study estimates for total electricity generation (NREL 2012) under 

favorable economic and technological progress conditions, and TRR estimates are from the more 

consistent assessment conducted for multiple renewable resources by Lopez et al. (2012). The 

estimates reported in this study are therefore updates to estimates reported in the Program Plan 

(DOE 2011a) and are developed with a more consistent basis for both technical and economic 

potentials. For example, the solar and wind technical resource potentials in Lopez et al. (2012) 

are characterized with significant technical detail and consistently across resource types, while 

the resource availability estimates for solar and wind in the Program Plan are best described as 

estimates of economic potential as defined in the present report. 

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35 

Table 5. Availability, Current Consumption, and Projected Consumption for Fossil and Nuclear 

Resources 

Resource Metric

Fossil and Nuclear Pathways a

Natural gas b Coal c

(with CCS)

Nuclear d 

(high temp. 

electrolysis)

Nuclear d

(thermochemical)

Resource Availability

 Economic Resource Potential 305 Tcf 259 B tons 809 M lb U3O8

 Technically Recoverable Resource 2,200 Tcf 483 B tons 1,841 M lb U3O8

Resource Consumption (without hydrogen for FCEVs) e

 Current [2012] 25.5 Tcf 891 M tons 770 TWh

 Reference Case: 2040 29.5 Tcf 1,071 M tons 903 TWh

 GHG $25 Case: 2040 26.9 Tcf 132 M tons 1,788 TWh

Resource to Produce Hydrogen for 20 & 50 million FCEVs f

 50 M FCEVs 1.7 Tcf 137 M tons 278 TWh 292 TWh

 20 M FCEVs 0.7 Tcf 55 M tons 111 TWh 117 TWh

Percent Increase in 2040 Resource Consumption for 20 & 50 million FCEVs

 Reference Case 20 M FCEVs 2% 6% 12% 13%

50 M FCEVS 6% 13% 31% 32%

 GHG $25 Case 20 M FCEVs 2% 41% 6% 7%

50 M FCEVS 5% 103% 16% 16%

B = billion; GHG $25 = 2013 AEO Greenhouse Gas $25; M = million; 

Technically Recoverable Resource = sum of economic and technical potentials 

a Calculations were made to determine the hydrogen quantity required. Some systems require input energy such as 

electricity or produce useful byproducts such as heat or electricity. 

b Natural gas economic potential from 2010 Proved Reserves (Annual Energy Review 2011, Table 4.2 [EIA 2012c]) 

and technical potential from 2009 Total Technically Recoverable Resources (Annual Energy Review 2011, Table 

4.1). 

c Coal economic potential from 2011 Estimated Recoverable Reserves and technical potential from Demonstrated 

Reserve Base from the 2011 Annual Coal Report (EIA 2012d). Resource availability values are from EIA’s 2010 

Annual Energy Review (EIA 2011), available at http://www.eia.gov/totalenergy/data/annual. d The two nuclear production pathways are for High Temperature Electrolysis and Thermochemical, as described 

above. Uranium resource economic potential is from 2008 uranium reserves at a forward-cost category of up to 

$50/lb U3O8, and technical potential is at a forward-cost category of up to $100/lb U3O8 (Annual Energy Review 

2011, Table 4.10).

e Current consumption values from EIA online data tables for natural gas (http://www.eia.gov/dnav/ng/

ng_sum_lsum_dcu_nus_a.htm), the Quarterly Coal Report 

(http://www.eia.gov/coal/production/quarterly/pdf/tes1p01p1.pdf) and the Electricity Supply, Disposition, Prices and 

Emissions table for nuclear (http://www.eia.gov/oiaf/aeo/tablebrowser/). Projected resource consumption values in 

2040 are from the Reference Case and Greenhouse Gas $25 scenario from the 2013 Annual Energy Outlook (EIA 

2013a). f

See Figure 16 and related discussion. Fifty and 20 million FCEVs consume 10 and 4 MMT hydrogen per year, 

respectively, assuming 12,000 miles per year per vehicle and 60 miles per kg hydrogen. Resources required are 

determined from the H2A case study production efficiencies summarized in Table 3.

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36 

Table 6. Availability, Current Consumption, and Projected Consumption for Biomass, Wind and 

Solar Resources 

Resource Metric

Renewable Pathways

Biomass a Wind b

(on/offshore)

Solar c

(PV & CSP)

Resource Availability

 Economic Resource Potential 900 M tons 2,000 TWh 1,000 TWh

 Technically Recoverable Resource 417–1,094 M tons 50,000 TWh 400,000 TWh

Resource Consumption (without hydrogen for FCEVs) d

 Current [2012] 245 M tons 137 TWh 3.5 TWh

 Reference Case: 2040 433 M tons 252 TWh 59 TWh

 GHG $25 Case: 2040 474 M tons 616 TWh 313 TWh

Resource to Produce Hydrogen for 20 & 50 million FCEVs e

 50 M FCEVs 130 M tons 460 TWh 460 TWh

 20 M FCEVs 52 M tons 184 TWh 184 TWh

Percent Increase in 2040 Resource Consumption for 20 & 50 million FCEVs 

 Reference Case 20 M FCEVs 13% 73% 161%

50 M FCEVS 33% 183% 401%

 GHG $25 Case 20 M FCEVs 12% 30% 47%

50 M FCEVS 30% 75% 116%

Technically Recoverable Resource = sum of economic and technical potentials (see note a below for biomass); 

PV = photovoltaic; GHG $25 = 2013 AEO Greenhouse Gas $25 a Biomass economic potential is the sum of 350 M tons of (plateaued) supply projected between 2020 and 2032 in the 

2013 AEO Early Release Greenhouse Gas $25 scenario (EIA 2013a) and 550 M tons for biopower by 2050 in the 

high demand REF Study scenario (NREL 2012). This result is unique to this study and represents an economic 

potential corresponding to a future with high demand for low-carbon resources and a relatively high degree of 

technological development. The technical potential range includes a low value for current resources from Lopez et al. 

(2012) and a high value from the Billion Ton Study update baseline scenario in 2030, with a price of $60 per dry ton 

(DOE 2011b). Biomass consumption is not sufficient to meet RFS requirements and would require an additional ~100 

M tons (~1.7 quads) to meet RFS requirements.

b Wind resource economic potential is assumed to be equal to the projected 2050 production projection from the REF 

Study (NREL 2012).

c Solar resource economic potential is assumed to be equal to the projected 2050 production projection from the REF 

Study (NREL 2012).

d Resource consumption values are from the Reference Case (Ref) and Greenhouse Gas $25 (GHG$25) scenario 

from Annual Energy Outlook: 2013. Wind and Solar electricity values are from the Renewable Energy Generating 

Capacity and Generation table (http://www.eia.gov/oiaf/aeo/tablebrowser/). Biomass consumption is from multiple 

sources in the Renewable Energy Consumption by Sector and Source table, with quads converted to million short 

tons assuming 8,500 Btu/lb (HHV) (Lopez et al. 2012). Biomass consumption projections do not meet RSF biofuel 

requirements and could involve an additional ~100 M tons if those requirements are met. e See Figure 16 and related discussion. Fifty and 20 million FCEVs consume 10 and 4 MMT hydrogen per year, 

respectively, assuming 12,000 miles per year per vehicle and 60 miles per kg hydrogen. Resources required are 

determined from the H2A case study production efficiencies summarized in Table 3.

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37 

Unlike the other Resource Availability estimates indicated, the biomass TRR potential is a range 

bounding the economic potential estimate. This reflects the high degree of variability among 

estimates and estimation methodologies for future biomass resources. In addition, the projected 

biomass consumption values in 2040 for the Reference Case and Greenhouse Gas $25 scenarios 

fall short of the RFS biofuel requirements by approximately 10 billion ethanol-equivalent gallons 

(EIA 2013a). With market and policy conditions sufficient to actually meet the RFS 

requirements, these scenarios could involve an additional consumption of ~100 M tons (~1.7 

quads) biomass (assuming 50% thermal conversion). 

The additional resource consumption for producing 10 MMT hydrogen is also indicated 

graphically in Figure 17a for the BAU 2013 AEO Reference Case scenario (EIA 2013a). To 

allow for comparison, all resource values have been converted to quads from the values in Tables 

5 and 6. The white bars indicate current consumption in 2012, and the blue crosshatched bars 

represent projected consumption in 2040 under BAU conditions. The stacked solid blue bars 

indicate the additional resource consumption due to FCEVs. The degree to which consumption 

increases due to FCEV adoption varies by resource. The percent increases in projected 

consumption are indicated, as factor increases, along the horizontal axis for each resource. With 

respect to projected consumption in the Reference Case, these increases are 6% for natural gas, 

13% for coal, 31% for nuclear, 33% for biomass, 183% for wind, and 780% for solar. These 

factor increases are based on market outcome results from the 2013 AEO Reference Case (EIA 

2013a), and account for increases over consumption levels across all energy sectors, including 

buildings, electricity, industry and transportation. These results suggest that hydrogen demand 

from future market success with FCEVs would not place excessive strain on resources or 

production capacity for natural gas or coal, would comprise a significant portion of total demand 

for nuclear and biomass, and would significantly exceed expected demand for wind and solar. 

Any future scenario in which hydrogen vehicles attain strong market share by 2040 might 

involve policies or market forces not present in a BAU scenario, and these factors are likely to 

change demand for low-carbon resources in other sectors. For example, in a carbon-constrained 

future, there might be increased demand for wind and solar, which would lower the factor 

increases for those resources by increasing total projected consumption without market success 

with FCEVs. For this reason, projections from the 2013 AEO Greenhouse Gas $25 scenario are 

also included in Tables 5 and 6, and indicated visually in Figure 17b. As shown, the relative 

consumption increases are distinct from those shown in Figure 17a. Percent increases due 

hydrogen production for low-carbon resources are less because overall use of these resources has 

increased, and the percent increase for coal is significantly higher, 104% compared to 13%, 

because projected demand for coal has declined. Percent increases for each of the other resources 

are as follows: 6% for natural gas, 16% for nuclear, 30% for biomass, 75% for wind, and 147% 

for solar. These results suggest less relative strain on nuclear, wind, and solar resources

compared to the Reference Case. 

Each of the values indicated for coal in Figure 17 is based on different heating values. For the 

current consumption values, taken from the Quarterly Coal Report, the 2013 AEO consumption 

heating value for 2012 of 19.77 MMBtu per short ton is used. For projected consumption values, 

EIA reports 19.261 MMBtu per short ton in the Reference Case and 20.668 MMBtu per short ton 

in the Greenhouse Gas $25 case. The results expressed in quads in Figure 17 are therefore more 

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38 

consistent than the million short ton values reported in Table 5. The wind and solar values shown 

in quads have been converted to thermal equivalents assuming 9,760 Btu/kWh. 

(a)

(b)

Figure 17. Current and projected Reference Case (a) and Greenhouse Gas $25 scenario (b) energy 

consumption across all energy sectors by resource type, with requirements for 50 million FCEVs

Hydrogen required to meet 50% of FCEV demand in 2040 (or the hydrogen requirement for 50 million FCEVs) is 

shown as a stacked bar on top of the 2040 AEO 2013 Reference Case consumption values (a) and Greenhouse Gas 

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39 

$25 scenario values (b). The factor increase for each resource is shown in parentheses. Values are equivalent to 

those shown in Tables 5 and 6. Biomass consumption is not sufficient to meet RFS requirements and would require 

an addition ~1.7 quads to meet RFS requirements. 

* Nuclear values are for high temperature electrolysis. Thermochemical nuclear consumption results (not shown) are 

3.1 quads for FCEVs, representing factor increases of 1.32 (Reference Case) and 1.16 (Greenhouse Gas $25). 

Conceptual Comparison of Fixed and Flow Energy Potential 

Estimates

Conceptual comparisons of the economic and technical hydrogen production potentials for fossil, 

nuclear, and renewable energy resources are relevant in the context of long-term energy system 

dynamics. Over the long term, considerable technological advances or major shifts in market 

conditions are feasible and could significantly influence how economic and technical potential 

estimates are determined. Within this context, it is relevant to compare current resource estimates 

on a more conceptual basis that resolves the inherent “fixed” nature of fossil and uranium 

resources and the “flow” nature of renewable resources. High-level results for economic and 

technical potential estimates (summed as TRR estimates) and corresponding hydrogen 

production potentials are summarized in Table 7. These estimates are highly uncertain and 

speculative and are therefore indicated with limited significant figures. Estimates are shown in 

both physical resource units and as total hydrogen production potential in million metric tonnes 

of hydrogen (MMT) and quads. Renewable potentials are shown on an annual basis. As 

indicated, renewable hydrogen production potentials are distinct from fossil and nuclear 

potentials in that the economic hydrogen production potential for biomass falls within the 

uncertain range for TRR (as discussed above), the wind TRR is greater than the economic 

potential by a factor of 25, and the solar TRR is greater than the economic potential by a factor 

of 400. By comparison, fossil and nuclear TRR estimates for hydrogen production are greater 

than the corresponding economic potentials by factors ranging from 2 to 7. 

Table 7. Technical Resource Potential for Finite and Renewable Resources

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40 

Figure 18 places the “fixed” resource estimates for natural gas, coal, and uranium (indicated in 

quads) on a conceptually consistent temporal basis at the “flow” resource estimates for biomass, 

wind, and solar resources (quads per year). This comparison provides a general “ballpark” 

perspective on how renewable resource potentials compare to the “in the ground” estimates for 

fossil and uranium resources. Though nuclear, coal, and natural gas resource estimates will 

certainly change within an actual timeframe of 40 years, in response to changing consumption 

rates, economic conditions, and technological factors, they are indicated as conceptual fixed 

values based upon recent estimates of economic potential (low range) and TRR (high range). 

Figure 18 provides a visual depiction of the relative magnitudes of each resource type in terms of 

conceptual years: the solar TRR exceeds all fossil and uranium hydrogen production potential 

estimates within several years, and the wind TRR is comparable to domestic uranium, natural 

gas, and coal hydrogen production potentials on conceptual timeframes of approximately 5, 10 

and 30 years, respectively. In contrast, the biomass TRR range approaches the economic 

hydrogen production potentials for natural gas and uranium on a conceptual timeframe of 

approximately 30–40 years. As suggested by the figure inset, the TRR range for biomass is 

comparable to the cumulative economic hydrogen production potential estimates for solar, wind 

and biomass, ranging from 3–8 quads per year. 

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41 

 

Figure 18. Approximate hydrogen production potentials for each resource

Technical hydrogen production potentials from solar, wind, and biomass resources are quantified as flows (quads 

hydrogen per year) and shown accumulating linearly across a conceptual time scale. Though nuclear, coal, and 

natural gas resource estimates do change with time, in response to changing economic and technological factors, 

they are indicated as fixed values based upon recent estimates of economic potential (low range) and TRR (high 

range; the sum of economic and technical potentials). The dotted line and asterisk at the bottom of the figure (*) 

represent cumulative production of 20 MMT hydrogen per year over 40 years. All values are highly uncertain 

approximations. Resource categories are not necessarily consistent on an economic or technical basis across all 

resource types or categories. Values are consistent with those shown in Table 7 and discussed in earlier sections of 

the report. 

The secondary vertical axis indicates the resource production estimates in physical units, with the 

scale of 37 billion metric tonnes of hydrogen being equivalent to ~5,000 quads on an HHV basis.

For reference, the annual demand of 20 MMT hydrogen in 2040 from Figure 16 is indicated as 

increasing cumulatively over time in the dashed line and asterisk at the bottom of the figure, 

summing to a total of 0.82 billion metric tonnes over 40 years. This comparison reinforces the 

conclusion above that ample domestic, low-carbon energy resources are available (as measured 

in terms of technical potential for all resources and economic potential for fossil and nuclear 

resources) for high hydrogen demand scenarios requiring on the order of 10 MMT of hydrogen 

per year from any particular resource type. 

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42 

Conclusions 

The use of domestic low-carbon hydrogen in FCEVs is a promising option for reducing U.S. oil 

imports and GHG emissions. This study assesses energy resource requirements to produce 10 

MMT of hydrogen in a future Hydrogen Success scenario with 100 million FCEVs deployed by 

2040. We estimate the energy resources required to supply this level of hydrogen demand, 

illustrating how domestic resources could be relied on to produce large volumes of low-carbon 

hydrogen. We do not attempt to estimate the mix of production sources in 2040. Instead, we 

estimate what would be needed for any single resource to satisfy 50% (10 MMT) of the total 

2040 hydrogen demand level (20 MMT for 100 million FCEVs). These estimates build upon 

previous hydrogen production resource assessments by Milbrandt and Mann (2007, 2009), and 

extend previous comparisons to future hydrogen consumption levels (DOE 2011a) by drawing 

distinctions between economic and technical resource potentials. 

The spatial distribution of renewable hydrogen production potential is explored through a series 

of maps and is compared to the distribution of both population and gasoline consumption levels. 

For projected levels of resource consumption, a percent increase in projected nationwide 

consumption due to FCEV hydrogen demand is estimated for a BAU scenario (2013 AEO

Reference Case), as well as a carbon-constrained scenario in which low-carbon resources are 

relied upon to a greater degree (2013 AEO Greenhouse Gas $25 case). The results of this 

assessment suggest that ample low-carbon and domestic energy resources are available to supply 

hydrogen to future FCEV markets. 

Future work may consist of the following: 

• Compare resource use across multiple fuel types

• Examine regional variations in resource potential and availability 

• Incorporate additional constraints on resource potential, such as water resource 

limitations or barriers to developing delivery systems 

• Contribute to resource-constrained scenarios of transportation energy use 

• Include comparisons for non-LDV transportation demands (e.g., shipping, heavy-duty 

vehicles, air transport) 

• Contribute to supply curve calculations for low-carbon scenario studies. 

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at www.nrel.gov/publications.
43 

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