September 2004 • NREL/MP-560-36734 

Summary of Electrolytic 

Hydrogen Production 

Milestone Completion Report 

Johanna Ivy 

National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393 

303-275-3000 • www.nrel.gov 

Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337 
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1.0 Executive Summary 

This report provides a technical and economic overview of the electrolytic hydrogen 

production systems commercially available as of December 2003. The technical analysis 

focuses on five companies’ electrolysis units: Stuart IMET; Teledyne HM and EC; 

Proton HOGEN; Norsk Hydro HPE and Atmospheric; and Avalence Hydrofiller. Cost 

information was obtained for three different systems, and the economics of these 

processes were analyzed. 

The technical analysis found that currently, the largest electrolyzer unit sold produces 

only 380,000 kg H2/year. There are two limitations for electrolyzers of this size. If the 

system were to be used for forecourt production, fueling approximately 1,900 cars, 2.3 

MW of electricity would be required. This electricity demand would likely preclude the 

purchase of cheaper industrial electricity in the forecourt scenario, thus raising the price 

of hydrogen. If the system were to be used in a large hydrogen generation plant, the 

limited hydrogen production capacity means that a significant number of electrolyzer 

units would be required. For example, a 500,000 kg/day hydrogen generation plant using 

nuclear power and electrolysis would require 500 of the largest electrolyzer units 

available today. In this scenario, electrolyzers 10 to 100 times the size of today’s units 

could be utilized. 

An initial cost boundary analysis was completed to determine the effects of electricity 

price on hydrogen costs. For each electrolyzer, the specific system energy requirement 

was used to determine how much electricity is needed to produce hydrogen; no capital, 

operating or maintenance costs are included in the calculation. At current electrolyzer 

efficiencies, in order to produce hydrogen at lower than $3.00/kg, electricity costs must 

be lower than 4 and 5.5 cents per kWh. For an ideal system operating at 100% 

efficiency, electricity costs must be less then 7.5 cents per kWh to produce hydrogen at 

lower than $3.00/kg. This analysis demonstrates that regardless of any additional cost 

elements, electricity costs will be a major price contributor. 

The detailed economic analyses are based on three distinct systems for which cost and 

economic data were available. These data may or may not be representative of the costs 

and systems within each category. These three systems represent a small neighborhood 

(~20 kg/day), a small forecourt (~100 kg/day), and a forecourt size (~1000 kg/day). In 

this analysis, the hydrogen selling prices were $19.01/kg H2 for the small neighborhood 

size, $8.09/kg H2 for the small forecourt size, and $4.15/kg H2 for the forecourt size. The 

analysis was performed using year 2000 dollars, which were escalated to 2005 dollars. 

For the forecourt case, electricity represents 58% of the cost of the hydrogen, and the 

capital costs only 32%. For the small forecourt case, the electricity contribution drops to 

35% while the capital costs become the major cost factor at 55%. In the neighborhood 

case, the capital costs increase to 73%, but electricity costs are not insignificant at 17%. 

This analysis demonstrated that for all systems electricity price is a contributor to 

hydrogen price, but for small-sized electrolyzers, capital costs are more significant. 

1
2.0 Introduction 

The purpose of this report is to give an overview of the current state of electrolytic 

hydrogen production technologies, and to provide an economic analysis of the processes. 

The study focuses on five companies’ current electrolyzer lines: Stuart IMET; Teledyne 

HM and EC; Proton HOGEN; Norsk Hydro HPE and Atmospheric; and Avalence 

Hydrofiller. The report details the state of technology as of December 2003 for all five 

companies’ electrolysis units, and then analyzes the economics of three standard sized 

electrolysis processes. 

3.0 Analysis Methodology 

The technical details for each company’s electrolysis systems were obtained from 

research on the Internet, and from personal conversations with industry representatives. 

The data presented are representative of systems available in December 2003. A detailed 

summary of each electrolysis model included in this study can be found in Appendix A. 

For purposes of the analysis, the available electrolysis systems were categorized into five 

different size ranges: home, small neighborhood, neighborhood, small forecourt and 

forecourt. The term forecourt refers to a refueling station. The number of cars served 

and hydrogen production rate for each size are as follows: 

• The home size will serve the fuel needs of 1- 5 cars with a hydrogen production 

rate of 200-1000 kg H2/year. 

• The small neighborhood size will serve the fuel needs of 5-50 cars with a 

hydrogen production rate of 1000-10,000 kg H2/year. 

• The neighborhood size will serve the fuel needs of 50-150 cars with a hydrogen 

production rate of 10,000 – 30,000 kg H2/year. 

• The small forecourt size, which could be a single hydrogen pump at an existing 

station, will serve 150 – 500 cars with a hydrogen production rate of 30,000 – 

100,000 kg H2/year. 

• A full hydrogen forecourt will serve more then 500 cars per year with a hydrogen 

production rate of greater then 100,000 kg H2/year. 

The number of cars served was determined by calculating that a car requires 

approximately 200 kg of hydrogen per year. This 200 kg requirement assumes that on 

average a car travels 12,000 miles per year, and that a vehicle will travel 60 miles/kg of 

hydrogen. 

Table 1 below illustrates where each manufacture’s electrolysis models fit into these 

categories. 

2
Table 1: Hydrogen Station Size 

Manufacturer Model 

Hydrogen 

Production Rate 

# of cars 

served Station size 

kg/day kg/year 

Avalence Hydrofiller 15 0.9 315 1.6 Home 

Proton HOGEN 20 1 396 2.0 Home 

Proton HOGEN 40 2 789 3.9 Home 

Avalence Hydrofiller 50 3 1182 6 Small Neighborhood 

Teledyne HM-50 6 2205 11 Small Neighborhood 

Stuart IMET 300, 1 cell stack, 300 cm3 6 2364 12 Small Neighborhood 

Avalence Hydrofiller 175 10 3622 18 Small Neighborhood 

Stuart IMET 1000, 1 cell stack, 1000 cm3 11 3939 20 Small Neighborhood 

Teledyne HM-100 12 4410 22 Small Neighborhood 

Teledyne HM-125 15 5514 28 Small Neighborhood 

Teledyne HM-150 18 6615 33 Small Neighborhood 

Proton HOGEN 3801 22 7875 39 Small Neighborhood 

Norsk HPE 10 22 7875 39 Small Neighborhood 

Teledyne HM-200 24 8820 44 Small Neighborhood 

Norsk HPE 12 26 9450 47 Small Neighborhood 

Norsk HPE 16 35 12600 63 Neighborhood 

Norsk HPE 20 43 15747 79 Neighborhood 

Norsk HPE 24 52 18897 94 Neighborhood 

Teledyne EC-500 60 22047 110 Neighborhood 

Stuart IMET 1000, 2 cell stack, 1000 cm3 65 23622 118 Neighborhood 

Norsk HPE 30 65 23622 118 Neighborhood 

Teledyne EC-600 72 26457 132 Neighborhood 

Norsk HPE 40 86 31494 157 Small Forecourt 

Teledyne EC-750 91 33069 165 Small Forecourt 

Stuart IMET 1000, 3 cell stack, 1000 cm3 97 35433 177 Small Forecourt 

Norsk Atmospheric Type No.5010 (4000 Amp DC) 108 39369 197 Small Forecourt 

Norsk Atmospheric Type No.5010 (5150 Amp DC) 108 39369 197 Small Forecourt 

Norsk HPE 50 108 39369 197 Small Forecourt 

Stuart IMET 1000, 4 cell stack, 1000 cm3 129 47241 236 Small Forecourt 

Norsk HPW 60 129 47241 236 Small Forecourt 

Stuart IMET 1000, 4 cell stack, 1000 cm3 194 70863 354 Small Forecourt 

Norsk Atmospheric Type No.5020 (4000 Amp DC) 324 118104 591 Forecourt 

Norsk Atmospheric Type No.5020 (5150 Amp DC) 324 118104 591 Forecourt 

Norsk Atmospheric Type No.5030 (4000 Amp DC) 647 236205 1181 Forecourt 

Norsk Atmospheric Type No.5030 (5150 Amp DC) 647 236205 1181 Forecourt 

Norsk Atmospheric Type No.5040 (4000 Amp DC) 813 296832 1484 Forecourt 

Norsk Atmospheric Type No.5040 (5150 Amp DC) 1046 381864 1909 Forecourt 

1

 Proton’s HOGEN 380 has now been replaced by the HOGEN H Series. The HOGEN 380 pre-production 

unit was used because data on Proton’s H Series Electrolyzers were not available in December 2003, which 

is the cutoff time for this report. 

3 
The table illustrates the production rates of current electrolysis units. Today, only Norsk 

Hydro makes an electrolyzer large enough to be considered a forecourt-sized system. 

Alkaline producers Teledyne and Stuart manufacture systems in the small neighborhood, 

neighborhood and small forecourt range, and Avalence’s small unipolar alkaline 

electrolyzers are currently only sized for the home and small neighborhood. In contrast, 

Proton Exchange Membrane (PEM) electrolysis units, produced by Proton, are only sized 

for the home or small neighborhood system. This is a typical trend in the industry today 

as the high capital costs of PEM units limit their current viability in the large hydrogen 

production market, while alkaline units, with their lower capital costs, can produce across 

a range of hydrogen capacities. 

Additionally, the categories were used to allow cost data to be generalized by system 

size. The economic analyses are based on three distinct systems for which cost and 

economic data were available. These data may or may not be representative of the costs 

and systems within each category. The three systems represent a small neighborhood 

(~20 kg/day), a small forecourt (~100 kg/day), and a forecourt size (~1000 kg/day). The 

specific manufacturer and model analyzed is not presented as it was agreed that specific 

cost data would remain confidential. 

The initial version of this analysis, published March 19, 2004, used a beta version of the 

H2A model to calculate the discounted cash flow for the electrolysis process. In this 

version of the analysis, an updated version of the H2A model was used. 

4.0 Technology Description 

Hydrogen is produced via electrolysis by passing electricity through two electrodes in 

water. The water molecule is split and produces oxygen at the anode and hydrogen at the 

cathode. 

Three types of industrial electrolysis units are being produced today. Two involve an 

aqueous solution of potassium hydroxide (KOH), which is used because of its high 

conductivity, and are referred to as alkaline electrolyzers. These units can be either 

unipolar or bipolar. The unipolar electrolyzer resembles a tank and has electrodes 

connected in parallel. A membrane is placed between the cathode and anode, which 

separate the hydrogen and oxygen as the gasses are produced, but allows the transfer of 

ions. The bipolar design resembles a filter press. Electrolysis cells are connected in 

series, and hydrogen is produced on one side of the cell, oxygen on the other. Again, a 

membrane separates the electrodes. 

The third type of electrolysis unit is a Solid Polymer Electrolyte (SPE) electrolyzer. 

These systems are also referred to as PEM or Proton Exchange Membrane electrolyzers. 

In this unit the electrolyte is a solid ion conducting membrane as opposed to the aqueous 

solution in the alkaline electrolyzers. The membrane allows the H+ ion to transfer from 

the anode side of the membrane to the cathode side, where it forms hydrogen. The SPE 

membrane also serves to separate the hydrogen and oxygen gasses, as oxygen is produced 

4
at the anode on one side of the membrane and hydrogen is produced on the opposite side 

of the membrane. 

The Avalence Hydrofiller is the only unipolar electrolyzer discussed in this study. Norsk 

Hydro, Stuart, and Teledyne all produce bipolar electrolysis units. These units are 

currently capable of producing the largest amounts of hydrogen, and today are in use 

worldwide. The PEM electrolysis unit is the newest of the technologies discussed in this 

report, and Proton is the only PEM electrolyzer discussed in this study. 

Regardless of the technology, the overall electrolysis reaction is the same: 

H2O → 1⁄2 O2 + H2 

However, reaction at each electrode differs between PEM and alkaline systems. In a 

PEM system the reactions at the electrodes are: 

PEM Hydrogen Production at the Cathode 

2 H+

 + 2e- → H2 

PEM Oxygen Production at the Anode 

H2O → 1⁄2 O2 + 2 H+

 + 2eIn an alkaline system the reaction at each electrode are: 

Alkaline Hydrogen Production at the Cathode 

2 H2O + 2e- → H2 + 2OHAlkaline Oxygen Production at the Anode 

2OH- → 1⁄2 O2 + 2 H2O + 2e5.0 Process Design 

A typical electrolysis process diagram is shown in Figure 1 below. Note that different 

processes will use different pieces of equipment. For example, PEM units will not 

require the KOH mixing tank, as no electrolytic solution is needed for these electrolyzers. 

Another example involves water purification equipment. Water quality requirements 

differ across electrolyzers. Some units include water purification inside their hydrogen 

generation unit, while others require an external deionizer or reverse osmosis unit before 

water is fed to the cell stacks. For systems that do not include a water purifier, one is 

added in the process flow. A water storage tank may be included to ensure that the 

process has adequate water in storage in case the water system is interrupted. Each 

system has a hydrogen generation unit that integrates the electrolysis stack, gas 

purification and dryer, and heat removal. Electrolyte circulation is also included in the 

5
hydrogen generation unit in alkaline systems. The integrated system is usually enclosed 

in a container or is installed as a complete package. Oxygen and purified hydrogen are 

produced from the hydrogen generation unit. If desired, a compressor and hydrogen 

storage can be added to the system. Although hydrogen storage and compression are 

included in the process diagram below, for purposes of this analysis, hydrogen storage is 

not included. It is assumed that as the hydrogen is produced it is fed directly into a 

pipeline or truck. In addition, note that there is no oxygen compression and storage. For 

the purposes of this analysis, oxygen production is not considered. 

Typical utilities that the electrolysis systems need include electricity for electrolysis and 

other peripheral equipment; cooling water for the hydrogen generation unit; prepressurization gas; and inert gas. 

Process H2O High Purity H2O 

Water Purifier 

Power Supply y Electrolysis module 

y Electrolyte circulation Compressor 

y Hydrogen Gas Dryer/Purifier 

Utilities 

Feed Water Storage Tank 

Hydrogen Storage 

Prepressurization 

Gas 

KOH Mixing Tank 

>99% Pure H2 H2 

High Purity H2O 

Instrument 

Air 

Cooling 

Water 

Electrolyte Solution 

Hydrogen 

Generation 

Unit 

Figure 1: Process Flow Diagram 

5.1. Mass Balance Results 

A simplified process flow is displayed in Figure 2 below to help illustrate the mass 

balance of the electrolysis system. The mass balance data provided are based on each of 

the manufacturers’ largest electrolysis system: the Stuart IMET 1000, the Teledyne EC750, the Proton Hogen 380, the Norsk Hydro Atmospheric Type No.5040 (5150 Amp 

DC) and the Avalence Hydrofiller 175. 

6
Gas Purification 

Water (4) 

Electrolyzer 

Hydrogen (2) 

O xygen (3) 

Water (1) 

Hydrogen Generation Unit 

Hydro gen 

O xyge n 

l/hr kg/hr kmole/hr Nm3/hr kg/hr kmole/hr Nm3/hr kg/hr kmole/hr l/hr kg/hr kmole/hr 

Stuart * 60 60 3.3 60 5.4 2.7 30 43 1.3 11.80 11.80 0.7 

Teledyne 42 42 2.3 42 3.77 1.9 21 30.01 0.9 8.21 8.21 0.5 

Proton 8.4 8.4 0.47 10 0.90 0.45 5.0 7.1 0.22 0.40 0.40 0.02 

Norsk 485 485 26.9 485 43.59 21.6 242.5 346.51 10.8 94.82 94.82 5.3 

Avalance ** 4.5 4.5 0.2 5 0.45 0.2 2.5 3.57 0.1 0.48 0.48 0.03 

Stream (3) 

Oxygen Product 

Stream (4) 

Water Removal 

Stream (1) 

Water 

Stream (2) 

Hydrogen Product 

* Assumes stoichiometric production of oxygen 

** Assumes stoichiometric production of oxygen and 1 L of water input per kg of hydrogen produced. 

Figure 2: Mass Balance 

The product streams are assumed to be 100% oxygen or hydrogen because typically the 

amount of contaminant in the product streams is so small as to be considered negligible. 

The hydrogen purities for the above systems range from 99.9 - 99.9998%, and the oxygen 

purities, where provided, range from 99.2-99.9993%. The difference in gas purities 

depend on the gas purification technology used in each system. 

5.2. Energy Balance Results 

The energy balance in Table 2 details the energy required for hydrogen production by 

each manufacturer’s largest hydrogen generation system. Note that only Stuart and 

Norsk Hydro provide the actual energy requirement of the electrolyzer. Stuart also 

provided the energy requirement of the entire system, while Norsk Hydro’s system 

energy requirement was calculated by using the power requirements of the system and 

the hydrogen generation rate. Avalence’s system energy requirement was calculated in 

the same manner. Proton and Teledyne both provide energy requirement data based on 

the entire hydrogen production system. Only Norsk Hydro’s system energy requirements 

include compression: one water injected screw compressor followed by a reciprocating 

compressor to bring the gas to 33bar (480 psi). 

7
Table 2: Energy Balance 

Energy Required: 

System 

Energy 

Required: 

Electrolyzer 

Hydrogen 

Production 

System 

Power 

Requirement 

Manufacturer 

Model kWh/Nm3 kWh/kg kWh/Nm3 Nm3/hr kW 

Stuart: IMET 

1000 4.8 4.2 60 288 

Teledyne: EC750 5.6 - 42 235.2 

Proton: HOGEN 

380 6.3 - 10 63 

Norsk Hydro: 

Atmospheric 

Type No.5040 

(5150 Amp DC) 4.8 4.3 485 2330 

Avalence: 

Hydrofiller 175 5.4 - 4.6 25 

53.4 

62.3 

70.1 

53.5 

60.5 

6.0 Efficiency Results 

Efficient conversion of water and electricity to hydrogen is critical to the electrolytic 

hydrogen production technology. 

6.1. Conversion Efficiency 

The conversion efficiency of water to hydrogen is shown in Table 3. Overall, the 

conversion efficiency is high, ranging from 80-95%. 

Table 3: Conversion Efficiency 

Reactants 

Product 

H2 

Product 

O2 

Conversion 

efficiency 

kg/hr kg/hr kg/hr % 

Stuart: IMET 1000 60 43 80% 

Teledyne: EC-750 42 30 80% 

Proton: GEN 380 8.4 7.1 95% 

Norsk Hydro: Atmospheric Type No.5040 (5150 

Amp DC) 485 347 80% 

Avalence: Hydrofiller 175 4.5 3.6 89% 

5.4 

3.8 

HO 0.9 

434 

0.45 

6.2. Energy efficiency 

Energy efficiency is defined as the higher heating value (HHV) of hydrogen divided by 

the energy consumed by the electrolysis system per kilogram of hydrogen produced. The 

justification for using HHV can be seen in Appendix B. The energy efficiency of the 

electrolysis process is shown in Table 4. The energy efficiency ranges from 56-73%. 

Proton’s PEM process has the lowest efficiency at 56% and both Stuart’s and Norsk 

Hydro’s bipolar alkaline efficiencies are the highest at 73%. An efficiency goal for 

electrolyzers in the future has been reported to be in the 50 kWh/kg range, or a system 

efficiency of 78%. However, this 78% includes compression of the hydrogen gas to 6000 

8
psi. Currently, these electrolyzers, other then Avalence’s, reach a pressure ranging from 

60-435 psig for the power requirements presented. These efficiencies would decrease if 

additional compression up to 6000 psig were included. Only Avalence’s energy 

requirement of 60.5 kWh/kg includes reaching hydrogen pressures in the 6000 psig 

range. 

Note that in this study the energy requirement of the entire electrolysis system is used to 

calculate the efficiency, not just the efficiency of the electrolyzer. As an example, the 

electrolyzer alone for the Stuart IMET 1000 requires 46.8 kWh/kg (4.2 kWh/Nm3

), which 

corresponds to 83% efficiency when you divide the HHV of hydrogen by the electrolyzer 

power requirement. However, when you include the rectifier and auxiliaries the energy 

requirement becomes 53.5 kWh/kg or 73% efficient. As a result, when referring to the 

“System Energy Required” in this study, the value refers to the entire electrolysis system, 

not just the electrolyzer itself. 

Table 4: Energy Efficiency 

Energy 

Required 

System 

HHV of Hydrogen 

(equivalent to 142 MJ/kg) 

System 

Efficiency 

Production 

Pressure 

kWh/kg kWh/kg % psig 

Stuart: IMET 1000 53.4 73 360 

Teledyne: EC-750 62.3 63 60-115 

Proton: HOGEN 380 70.1 56 200 

Norsk Hydro: Atmospheric 

Type No.5040 (5150 Amp 

DC) 53.5 73 435 

Avalence: Hydrofiller 175 60.5 64 

up to 

10,000 

39 

39 

39 

39 

39 

7.0 Capital and Operating Cost Results 

An initial boundary analysis was completed to determine the effects of electricity price 

on hydrogen costs, and the results are shown in Figure 3. For each electrolyzer, the 

specific system energy requirement is used to determine how much electricity is needed 

to produce hydrogen; no capital, operating or maintenance costs are included in the 

calculation. The system energy requirement used is the lowest energy requirement 

reported for each manufacturer. This graph shows that, at current electrolyzer 

efficiencies, in order to produce hydrogen at lower than $3.00/kg, electricity costs must 

be between 4 and 5.5¢/kWh. In order to produce hydrogen for less than $3.00/kg with a 

system that is 100% efficient, electricity prices must be less than 7.5¢/kWh. The U.S. 

Department of Energy’s Energy Information Administration (EIA) reports 2002 

industrial, commercial, and residential electricity prices at 4.83, 7.89, and 8.45¢/kWh, 

respectively. Thus, if only electricity costs were incurred, current electrolyzers could 

produce hydrogen for $3.00/kg at industrial electricity prices; an ideal system could 

produce hydrogen for $3.00/kg at slightly lower then commercial prices. This analysis 

9
shows that regardless of any additional cost elements, electricity costs will be a major 

price contributor. H2 cost $/kg 

Hydrogen costs via electrolysis with electricity costs only 

$8.00 

Commercial System Efficiencies (54-67 kWh/kg) $7.00 

$6.00 Ideal System (HHV of Hydrogen 39 kWh/kg) 

$5.00 

$4.00 

` 

$3.00 

$2.00 

$1.00 

$0.00 

0.000 0.010 0.020 0.030 0.040 0.050 0.060 0.070 0.080 0.090 0.100 

Electricity costs $/kWh 

Figure 32 

8.0 Discounted Cash Flow Results 

The discounted cash flow analysis was completed using the H2A model. The specifics 

for each of the three systems analyzed will not be presented here, as each vendor 

requested that the detailed economic data they provided remain confidential. Nonconfidential data and parameters are provided in Table 5, and show the cost assumptions 

that were used in the analysis which are common between all three systems analyzed. 

These parameters are included to help provide transparency in the analysis. 

Table 5: DCF Parameters 

Parameter Assumption 

Process Parameters 

Primary Feedstock Electricity and Water 

Electricity Used Industrial Electricity 

Conversion Technology Electrolysis 

Financial Parameters 

Start-up Year 2005 

After-Tax Real IRR (%) 10 

Depreciation Type MACRS 

2

 The Proton efficiency is based on the HOGEN 380 series, which is no longer available. Current 

efficiencies of Proton systems are in the 62-70 kWh/kg range 

10 
Parameter tion 

Depreciation Schedule Length (No. of Years) 7 

Analysis Period (years) 40 

Plant Life (years) 40 

Assumed Inflation Rate (%) 1.9 

State Income Taxes (%) 6 

Federal Income Taxes (%) 35 

Effective Tax Rate (%) 38.9 

Operating Capacity Factor (%) 97 

% Equity Financing 100 

Length of Construction Period (years) 1 

% of Capital Spent in 1st Year of Construction 100 

Start-up Time (years) 1 

% of Revenues During Start-up (%) 75 

% of Variable Operating Costs During Start-up (%) 75 

% of Fixed Operating Costs During Start-up (%) 100 

Salvage Value of Capital (% of Total Capital Investment) 10 

Decommissioning Costs (% of Total Capital Investment) 10 

Replacement Capital Parameters 

Electrolyzer cell stack lifetime (years) 5-15 

Indirect Depreciable Capital Parameters 

Buildings (% of fixed capital investment) 14 

Yard Improvements (% of fixed capital investment) 3.5 

Construction (% of fixed capital investment) 9 

Engineering and design (% of fixed capital investment) 8 

Contingency (% of fixed capital investment) 25-30 

Non Depreciable Capital Parameters 

Land ($/acre) 5,000 

O&M Parameters 

Burdened Labor ($/hour) 50 

Overhead and G&A (% of labor cost) 20 

Property Tax (% of depreciable capital costs) 1 

Insurance Rate (% of depreciable capital costs) 1 

Assump

2005 was chosen as the startup year for this analysis because the study focuses on 

currently available technology. Presently, the electrolysis industry meets a smaller 

market demand then would exist if hydrogen were in use as a transportation fuel. As the 

demand for hydrogen increases, capital costs will come down due to mass production. 

The economic results of this study should be considered representative of the electrolysis 

market as it stands today and in the near future, but not representative of long term costs 

and prices. 

The three systems represented in the discount cash flow (DCF) analysis were the only 

three systems for which cost and economic data were available. These data may or may 

not be representative of the costs and systems within each category. 

11
Electricity prices for this analysis come from the H2A model, which projects electricity 

prices through 2070. The projections from 2001 through 2025 come from the latest 

Annual Energy Outlook (AEO 2004) recently published by EIA. The projections 

between 2025 and 2035 are extrapolations of the EIA projections. The projections past 

2035 are derived from growth rates that came from a Pacific Northwest National 

Laboratory long-term energy model called Climate Assessment Model (M-CAM). 

Industrial electricity prices, reported as 4.83¢/kWh for 2002 by EIA, were used for all 

base case economic analyses. While electrolyzers may be too small to obtain the cheaper 

electricity prices usually available to industrial users, using such prices in this analysis 

sets the boundary for research goals on other parameters such as capital costs and 

efficiency. Additionally, sensitivity analyses were run to determine the impact of higher 

electricity prices on the hydrogen selling price results. 

The results of the base case discounted cash flow analyses are shown in Table 6. The 

hydrogen selling price ranges from $19.01/kg for the small neighborhood size to $4.15/kg 

for the forecourt size. The analysis was performed using year 2000 dollars, which were 

escalated to 2005 dollars. The after-tax real IRR was fixed at 10% and the hydrogen 

selling price was varied until the NPV equaled zero. 

Table 6: 

DCF CALCULATION OUTPUTS: Small Neighborhood Small Forecourt Forecourt 

Required Hydrogen Selling Price (Year 

2000 Real Dollars) $19.01 $8.09 $4.15 

Required Hydrogen Selling Price 

(Nominal Startup Year Dollars) $20.88 $8.89 $4.56 

After-Tax Real IRR 10.0% 10.0% 10.0% 

Pre-Tax Real IRR 13.0% 12.5% 12.7% 

After-Tax Nominal IRR 12.1% 12.1% 12.1% 

Pre-Tax Nominal IRR 15.1% 14.6% 14.9% 

DCF Outputs 

The above DCF calculations yielded the specific item costs for each of the systems, and 

are shown in Table 7. The feedstock cost contribution includes only the cost of 

electricity for the system. Although it can be argued that electricity is not a feedstock, it 

was entered as such so that the electricity cost contribution can be easily distinguished 

from other utilities such as the process water, cooling water and inert gas contribution, 

which can be seen in the variable O&M cost contribution row. As anticipated, the cost of 

electricity is a factor in all three of the cases. 

12
Table 7: DCF Item Costs 

Specific Item Costs 

Small 

Neighborhood 

Small 

Forecourt Forecourt 

Item Cost Cost Cost Units 

Capital Cost Contribution $13.90 $4.43 $1.32 /kg of H2 

Feedstock Cost Contribution $3.15 $2.80 $2.41 /kg of H2 

Other Raw Material Cost Contribution $0.00 $0.00 $0.02 /kg of H2 

Fixed O&M (labor etc.) Cost Contribution $1.93 $0.80 $0.37 /kg of H2 

Variable O&M Cost Contribution $0.01 $0.05 $0.03 /kg of H2 

Decommissioning Costs $0.02 $0.01 $0.00 /kg of H2 

Byproduct Credit Cost Contribution $0.00 $0.00 $0.00 /kg of H2 

Note that a few factors differ between electrolysis cases, which will vary the cost 

numbers. First, each system has different electrolyzer system efficiencies. As a result, 

the systems will need different amount of electricity to make the same amount of 

hydrogen. Second, different electrolyzers have different system lives. This analysis had 

an analysis period and plant life of 40 years. This time was chosen to be consistent with 

the H2A guidelines. However, electrolyzers have a stack life of 5-15 years, so different 

manufacturers stacks will need to be replaced at different intervals. The systems with the 

shorter system life will have higher capital costs. 

The graph in Figure 4 better illustrates the different cost contributions for all three cases, 

along with the difference in cost contributions across the cases. For all three cases, the 

other raw material cost contribution, decommissioning cost contribution, and variable 

O&M cost contribution are negligible. The other raw material cost contribution includes 

the KOH electrolyte, when applicable. The variable O&M costs include utility costs: 

process or de-mineralized water, cooling water and inert gas. The inert gas is needed for 

instruments and initial system pressurization. For all electrolysis units, capital costs and 

feedstock costs are the two largest cost contributors, and fixed O&M costs are the third 

largest contributor. 

13
$/kg Hydrogen (2000 dollars) 

$20.00 

$18.00 

$16.00 

$14.00 

$12.00 

$10.00 

$8.00 

$6.00 

$4.00 

$2.00 

$-

Hydrogen Selling Price 

Industrial Electricity 

$2.41 $2.80 $3.15 

$1.32 

$4.43 

$13.90 

$0.37 

$0.80 

$1.93 

Decommissioning Costs 

Other Raw Material Costs 

Other Variable Costs (including utilities) 

Fixed O&M 

Capital Costs 

Feedstock Costs 

Forecourt - $4.15/kg Small Forecourt - $8.09/kg Neighborhood - $19.01/kg 

(~1000 kg/day) (~100 kg/day) (~20 kg/day) 

Hydrogen Market 

Figure 4 

Figure 5 illustrates the driving cost for each of the three cases. For the forecourt case, 

electricity represents 58% of the cost of the hydrogen, and the capital costs only 32%. 

For the small forecourt case, the electricity contribution drops to 35% while the capital 

costs become the major cost factor at 55%. In the neighborhood case, the capital costs 

increase further to 73%, but electricity costs are not insignificant at 17%. This graph 

shows that the small neighborhood case and small forecourt cases must focus on capital 

cost reductions in order to be competitive with the forecourt cases. All three cases need 

to consider electricity cost as a factor and look to minimize those costs. 

14 
% Cost contribution 

Cost contribution (Year 2000 dollars) 

Industrial Electricity 

100% 

90% 

80% 

70% 

60% 

50% 

40% 

30% 

20% 

10% 

0% 

58% 

35% 

17% 

32% 

55% 

73% 

9% 10% 10% 

Forecourt - $4.15/kg Small Forecourt - $8.09/kg Neighborhood - $19.01/kg 

(~1000 kg/day) (~100 kg/day) (~20 kg/day) 

Hydrogen Market 

Feedstock Costs Capital Costs Fixed O&M 

Other Variable Costs (including utilities) Other Raw Material Costs Decommissioning Costs 

Figure 5 

The previous graph shows how dependent the electrolysis hydrogen costs are on 

electricity price. The price of electricity is important, and, as stated earlier, all of these 

costs are based on industrial electricity cost. In order to better determine the relationship 

between hydrogen price and electricity cost, a sensitivity analysis was run using higher 

commercial electricity prices. 

The graph in Figure 6 illustrates how an increase in electricity price to commercial levels 

increases the price of hydrogen. 

15
Hydrogen Costs ($/kg) 

Effects of Commercial Electricity vs Industrial Electrcity on H2 Costs 

(Year 2000 dollars) 

$25.00 

$20.00 

$15.00 

$10.00 

$5.00 

$-

Industrial Commercial Industrial Commercial Industrial Commercial 

$2.41 $3.68 $2.80 $4.28 $3.15 $4.82 $1.32

$1.35 $4.43 

$4.47 

$13.90 

$13.94 

$0.37 

$0.37 

$0.80 

$0.80 

$1.93 

$1.93 

Decommissioning Costs 

Other Raw Material Costs 

Other Variable Costs (including utilities) 

Fixed O&M 

Capital Costs 

Feedstock Costs 

$4.15/kg $5.45/kg $8.09/kg $9.61/kg $19.01/kg $20.72/kg 

Forecourt Small Forecourt Small Neighborhood 

(~1000 kg/day) (~100 kg/day) (~20 kg/day) 

Hydrogen Market 

Figure 6 

Obviously, an increase in electricity costs leads to an increase in hydrogen costs. For the 

forecourt case, the price of hydrogen increases from $4.15/kg to $5.45/kg, an increase of 

31%. The price of hydrogen from the small forecourt case increases from $8.09/kg to 

$9.61/kg, an increase of 19%. Finally, the small neighborhood case increases from 

$19.01/kg to $20.72/kg, an increase of 9%. As the electricity price represents a smaller 

percentage of the hydrogen price contributions in the small neighborhood and small 

forecourt cases, the effect of using commercial electricity is decreased. However, as the 

technology improves capital costs will become less of a factor, and the effect of higher 

electricity costs will be significant for all systems, regardless of size. 

9.0 Conclusions 

The cost of producing hydrogen via current electrolytic processes is largely dependent on 

the cost of electricity, the efficiencies of the systems, and the capital costs of the systems. 

The cost of electricity and the system efficiencies are interrelated because either an 

increase in efficiency or a decrease in electricity costs will bring down the overall 

electricity cost contribution. However, the amount the system efficiency can be increased 

is limited, and current industry goals are to reduce the energy requirement of the system 

to around 50 kWh/kg of hydrogen (a system efficiency of 78%), including compression 

of the hydrogen gas to 6000 psig. While this increased efficiency will bring down the 

electrical cost contribution, it will not reduce the cost as much as a significant reduction 

in electricity price. If forecourt systems can use industrial priced electricity as opposed to 

commercial priced electricity, hydrogen prices can be reduced by 31%. If even lower 

16
priced electricity alternatives are available they should be evaluated for electrolytic 

hydrogen production. 

The smaller systems have a two-fold challenge. First the capital costs of such systems 

need to be reduced so that those costs are no longer a major cost contribution. All 

electrolysis systems will benefit from a reduction in capital results as the hydrogen 

economy grows and these systems are mass produced, but the smaller systems will 

benefit the most, as the largest percentage of their hydrogen cost contribution comes from 

capital costs. Second, a scenario must exist where systems that require 15-300kW of 

electricity can negotiate for industrial electricity prices, as opposed to the costly 

commercial or residential prices. Such a scenario may require a shift in the price policies 

of the power companies. 

Another challenge of the electrolysis industry is the limited hydrogen production rates of 

the current units. Electrolysis units are sized to meet the demands of today’s hydrogen 

markets, but in a world where a hydrogen economy exists, today’s systems are too small 

to take advantage of the potential low cost, high volume electricity production methods 

such as wind and nuclear power. In order to effectively use the large amounts of 

electricity produced from such systems, electrolyzers 10 to 100 times the size of today’s 

units could be utilized. 

10.0 Future Work 

Several opportunities for further analysis exist, and are briefly described. 

10.1. Sensitivity Analyses 

Monte Carlo sensitivity analysis and tornado diagrams need to be completed for the next 

phase of this study to better understand the relationship between parameters included in 

the study and hydrogen price. 

10.2. Future electrolysis 

The purpose of this study was to develop an understanding of the electrolytic hydrogen 

production technology today. However, it may be years before this technology becomes 

an important player in the transportation fuel arena. The future costs of hydrogen 

production via electrolysis need to be researched and analyzed. 

10.3. Distributed generation and H2 production 

In order for electrolysis to produce low cost hydrogen, low cost electricity must be 

available. Scenarios need to be researched under which electricity could be available to 

forecourt sized electrolyzers for prices equal to or less than current industrial electricity 

prices. One of the scenarios that may be of particular interest in longer-term models is 

distributed hydrogen generation and its relationship to distributed power. 

10.4. “Off Peak” Electricity 

Oftentimes off peak electricity prices are used as a scenario by which electrolytic 

hydrogen production can become more economical. However, a better understanding of 

17
the off peak pricing and the effect that large-scale hydrogen production would have on 

off peak pricing is needed. 

10.5. Oxygen credits 

Oxygen by-product credits are another way electrolytic hydrogen is also made more 

economical. A better understanding of the current and future oxygen market is needed to 

justify such a credit. 

10.6. Power requirements 

The power requirements of electrolysis systems are not insignificant. The largest 

forecourt system requires 2.3 MW of power. A better understanding of the current power 

infrastructure needs to be understood, so the feasibility of delivering 2.3 MW of power to 

a forecourt station can be validated. The chart in Appendix A shows the power 

requirements for each size of electrolyzer in this study. 

10.7. Additional scenarios for small neighborhood and home 

The market for small neighborhood and home transportation fuel production does not 

currently exist. Additional analysis could be done to better understand how electrolysis 

units would have to function in such a market. As an example, in this analysis, the fixed 

O&M costs include the labor, general and administrative (G&A), property tax and 

insurance costs required for an electrolysis plant. For the small neighborhood size, it was 

assumed that these units would serve 5 to 50 cars a year, and would resemble a typical 

filling station, but smaller. However, the validity of this assumption needs to be 

examined for the small neighborhood and also for home refueling units. These 

electrolysis units may be different from the filling stations today and require less land, 

labor, insurance and property tax charges. Particularly with home electrolysis, the 

refueling units would need to operate as an appliance; the homeowner would do any 

maintenance with occasional expert help brought in for repairs. As a result, insurance 

and property taxes would not be assessed, and labor and G&A costs should be greatly 

reduced. This would lead to an overall reduction in the hydrogen costs for these smaller 

units. A better understanding of the needs and associated costs of hydrogen production in 

the home and neighborhood market is needed. 

18
11.0 Appendix 

11.1. Appendix A: Overview of Current Electrolysis Systems 

Manufacturer Model Technology 

Hydrogen Production 

Rate 

Hydrogen 

product 

pressure Energy Requirement 

Power 

required 

for max H2 

production 

Nm3/hr kg/hr psig kWh/Nm3 kWh/kg kW 

Min Max Min Max 

Avalence Hydrofiller 15 

Unipolar 

Alkaline 0.4 0.04 up to 10,000 psig 5.13 56.4 2 

Avalence Hydrofiller 50 

Unipolar 

Alkaline 1.3 0.1 up to 10,000 psig 5.33 59.2 7 

Avalence Hydrofiller 175 

Unipolar 

Alkaline 4.6 0.4 up to 10,000 psig 5.43 60.5 25 

Norsk Atmospheric Type 

No.5010 (4000 Amp DC) Bipolar Alkaline 0 50 0 4.5 0.3 4.8 53.4 240 

Norsk Atmospheric Type 

No.5010 (5150 Amp DC) Bipolar Alkaline 0 50 0 4.5 0.3 4.8 53.4 240 

Norsk Atmospheric Type 

No.5020 (4000 Amp DC) Bipolar Alkaline 50 150 4.5 13.5 0.3 4.8 53.4 720 

Norsk Atmospheric Type 

No.5020 (5150 Amp DC) Bipolar Alkaline 50 150 4.5 13.5 0.3 4.8 53.4 720 

Norsk Atmospheric Type 

No.5030 (4000 Amp DC) Bipolar Alkaline 150 300 13.5 27.0 0.3 4.8 53.4 1440 

Norsk Atmospheric Type 

No.5030 (5150 Amp DC) Bipolar Alkaline 150 300 13.5 27.0 0.3 4.8 53.4 1440 

3 This energy requirement was calculated using the input power value in kW provided by Avalence 

19
Manufacturer Model Technology 

Hydrogen Production 

Rate 

Hydrogen 

product 

pressure Energy Requirement 

Power 

required 

for max H2 

production 

Nm3/hr kg/hr psig kWh/Nm3 kWh/kg kW 

Min Max Min Max 

Norsk Atmospheric Type 

No.5040 (4000 Amp DC) Bipolar Alkaline 300 377 27.0 33.9 0.3 4.8 53.4 1810 

Norsk Atmospheric Type 

No.5040 (5150 Amp DC) Bipolar Alkaline 300 485 27.0 43.6 0.3 4.8 53.4 2328 

Norsk HPE 10 Bipolar Alkaline 10 0.9 232 4.84 53.4 48 Norsk HPE 12 Bipolar Alkaline 12 1.1 232 4.84 53.4 58 Norsk HPE 16 Bipolar Alkaline 16 1.4 232 4.84 53.4 77 Norsk HPE 20 Bipolar Alkaline 20 1.8 232 4.84 53.4 96 Norsk HPE 24 Bipolar Alkaline 24 2.2 232 4.84 53.4 115 Norsk HPE 30 Bipolar Alkaline 30 2.7 232 4.84 53.4 144 Norsk HPE 40 Bipolar Alkaline 40 3.6 232 4.84 53.4 192 Norsk HPE 50 Bipolar Alkaline 50 4.5 232 4.84 53.4 240 Norsk HPE 60 Bipolar Alkaline 60 5.4 232 4.84 53.4 288 Proton HOGEN H Series PEM 0 6 0 0.5 218 6.3 70.1 38 Proton HOGEN 20 PEM 0.5 0.04 200 5.6 62.3 3 Proton HOGEN 40 PEM 1 0.1 200 5.6 62.3 6 Proton HOGEN 380 PEM 10 0.9 200 6.3 70.1 63 Stuart IMET 1000, 1 cell stack, 1000 cm3 Bipolar Alkaline 3 5 0.3 0.4 360 4.8 53.4 24 Stuart IMET 1000, 2 cell stack, 1000 cm3 Bipolar Alkaline 16 30 1.4 2.7 360 4.8 53.4 144 4 This energy requirement was calculated using the total plant energy requirement in kW provided by Norsk Hydro 

20
Manufacturer Model Technology 

Hydrogen Production 

Rate 

Hydrogen 

product 

pressure Energy Requirement 

Power 

required 

for max H2 

production 

Nm3/hr kg/hr psig kWh/Nm3 kWh/kg kW 

Min Max Min Max 

Stuart IMET 1000, 3 cell stack, 1000 cm3 Bipolar Alkaline 31 45 2.8 4.0 360 4.8 53.4 216 Stuart IMET 1000, 4 cell stack, 1000 cm3 Bipolar Alkaline 64 60 5.8 5.4 360 4.8 53.4 288 Stuart IMET 1000, 6 cell stack, 1000 cm3 Bipolar Alkaline 90 8.1 360 4.8 53.4 360 Stuart IMET 300, 1 cell stack, 300 cm3 Bipolar Alkaline 1 3 0.1 0.3 360 4.9 54.5 15 Teledyne EC-500 Bipolar Alkaline 28 2.5 60-115 5.6 62.3 157 Teledyne EC-600 Bipolar Alkaline 33.6 3.0 60-115 5.6 62.3 188 Teledyne EC-750 Bipolar Alkaline 42 3.8 60-115 5.6 62.3 235 Teledyne HM-50 Bipolar Alkaline 2.8 0.3 100 6.1 67.9 17 Teledyne HM-100 Bipolar Alkaline 5.6 0.5 100 5.7 63.4 32 Teledyne HM-125 Bipolar Alkaline 7 0.6 100 5.7 63.4 40 Teledyne HM-150 Bipolar Alkaline 8.4 0.8 100 5.7 63.4 48 Teledyne HM-200 Bipolar Alkaline 11.2 1.0 100 5.3 59.0 59 

21
11.2. Appendix B: Higher Heating Value Justification 

The reaction of the formation of water is: 

H2 + 1⁄2 O2 -> H2O + energy 

At 25 C and 1 atm, the heat of formation of liquid water, or the energy released when 

water is formed in the reaction above is 39 kWh/kg of hydrogen. This value is the higher 

heating value (HHV) of hydrogen. The heat of formation of steam is 33 kWh/kg of 

hydrogen, and is the lower heating value (LHV) of hydrogen. 

The electrolysis reaction is the opposite of the formation of water reaction: 

H2O + energy -> H2 + 1⁄2 O2 

For purposes of electrolysis in this report liquid water, and not steam, is electrolyzed to 

produce hydrogen. So the reaction above is the reverse of the formation of liquid water. 

As a result, the amount of energy needed to create hydrogen from water using electrolysis 

is 39 kWh/kg. In order to determine the efficiency of the electrolysis process, the 

theoretical amount of energy needed, 39 kWh/kg of hydrogen, needs to be divided by the 

actual amount of energy used by the electrolysis unit to create hydrogen. 

The reason this distinction is important is because by using the lower heating value, we 

misrepresent the efficiency of electrolyzers. If you use LHV, to calculate the efficiencies, 

the efficiencies are low. For example, the Stuart IMET 1000 series electrolyzers are 

calculated to be 33 kWh/kg (LHV) ÷ 53.4 kWh/kg (the energy required to produce 1 kg 

of hydrogen using Stuart electrolyzer) which equals 64%. Using the HHV of 39 kWh/kg 

yields an efficiency of 73%. Another way to look at it is if the actual energy required to 

create 1 kg of hydrogen, 39 kWh/kg, is divided into the LHV value, the maximum 

efficiency of the electrolysis process is 33.3/39.4 = 84.5%. That is to say, that an 

electrolyzer that converts every kWh of input energy into hydrogen energy will have only 

84.5% efficiency, even though there are no losses5

. 

5

 Merer, Rupert. " RE: H2A Update." Personal e-mail. 17 Mar. 2004. 

22
11.3. Appendix C: Bibliography 

Andreassen, Knut. “Hydrogen Production by Electrolysis.” Hydrogen Power: 

Theroretical and Engineering Solutions. Ed T.O. Saetre. Proceedings of the 

HYPOTHESIS II Symposium, 18-22 Aug. 1997, Grimstad, Norway. London: 

Klewer Academic Publishers, 1998. 

Avalence LLC. “Hydrofiller Series Specifications.” Brochure. The 16th NREL Industry 

Growth Forum, 17 Nov. – 19 Nov. 2003, Hyatt Regency Austin. 

Bortel, Jeffrey. Personal interview. 11 Nov. 2003. 

Cloumann, Andres. “RE: Norsk systems.” E-mail to Matthew Kauffman. 5 Jan. 2004. 

Delivering the Power of Hydrogen. Stuart Energy, 20 Oct. 2003 

<http://www.stuartenergy.com/index.html>. 

Eliassen, Bjorn E. Norsk Hydro Electrolyzers Electrolyzer Hydrogen Plant 485 Nm3

/h 

Hydrogen. Norsk Hydro Electrolyzers, AS, 8 Aug. 2002. 

Fairlie, Matthew and Jim Hinatsu. Personal interview. 26 Jan. 2004. 

Goel, Nitin, Samantha Mirabal, H.A. (Skip) Ingley, and D. Yogi Goswami. “Hydrogen 

Production.” Advances in Solar Energy: An Annual Review of Research and 

Development 15 (2003): 411-6. 

Hinatsu, Jim. " RE: Electrolysis Analysis." Personal e-mail. 20 Feb. 2004. 

Hinatsu, Jim. " RE: H2A Update." Personal e-mail. 17 Mar. 2004. 

Hoffmann, Peter. Tomorrow’s Energy: Hydrogen, Fuel Cells and the Prospects for a 

Cleaner Planet. Cambridge, Massachusetts: The MIT Press, 2001. 

Maloney, Tom. "Electrolysis Report." Personal e-mail. 5 Mar. 2004. 

Merer, Rupert. " RE: H2A Update." Personal e-mail. 17 Mar. 2004. 

Norsk Hydro Electrolyzers AS: World Leader in Water Electrolysis. Norsk Hydro 

Electrolysers AS, 6 Nov. 2003 <http://www.electrolysers.com/>. 

Naqvi, Syed N. “Small-Scale Hydrogen Production by Electrolysis of Water.” SmallScale Hydrogen Production. Menlo Park, California: Process Economics 

Program, 2003. 

23
Peters, Max S., Klaus D. Timmerhaus, and Ronald E. West. Plant Design and 

Economics for Chemical Engineers. New York: McGraw Hill, 2003. 

Placet, Marylynn. “RE: Quick Question.” Personal e-mail. 30 Jan. 2004. 

Proton Energy Systems, Inc. Proton Energy Systems, Inc., 21 Oct. 2003 

<http://www.protonenergy.com/>. 

Proton Energy Systems, Inc. HOGEN Hydrogen Generators. 2002. 

<http://www.protonenergy.com/html/gasproducts/generators/files/industrial_broc 

hure-english.pdf>. 

Shimko, Martin. “NREL Electrolysis Analysis Report.” Personal e-mail. 8 Mar. 2004. 

Stuart Energy. Hydrogen Energy Station: Welcome to the Evolution of Energy. 2003. 

Teledyne Energy Systems, Inc. Description: Hydrogen Generation System. 

Teledyne Energy Systems, Inc. Teledyne Energy Systems, Inc., 21 Oct. 2003 

<http://www.teledyneenergysystems.com/>. 

Teledyne Titan EC Generator Series. Teledyne Energy Systems, Inc. 5 Jun. 2002. 

<http://www.teledyneenergysystems.com/pdf/Titan_EC_june02.pdf> 

Teledyne Titan HM Generator Series. Teledyne Energy Systems, Inc. 5 Jun. 2002. 

<http://www.teledyneenergysystems.com/pdf/Titan_EC_june02.pdf>. 

Turner, John. Personal interview. 19 Mar. 2004. 

24
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14. ABSTRACT (Maximum 200 Words) 

This report provides an overview of the current state of electrolytic hydrogen production techonologies and an 

economic analysis of the processes and systems available as of December 2003. The operating specifications of 

commercially available electrolyzers from five manufacturers, i.e., Stuart, Teledyne, Proton, Norsk Hydro, and 

Avalence, are summarized. Detailed economic analyses of three systems for which cost and economic data were 

available were completed. The contributions of the cost of electricity, system efficiency, and capital costs to the total 

cost of electrolysis are discussed. 

15. SUBJECT TERMS 

Economics of Electrolysis; Electrolytic Hydrogen Production; Technoeconomic Analysis of Electrolysis 

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