SPLITTING ANY KIND OF WATER WITH GLOBAL-SCALE, EARTH-ABUNDANT, LIGHT,

RECYCLABLE METALS TO MAKE HYDROGEN, HEAT AND

POTABLE WATER ON DEMAND ON DEMAND

Jerry M WoodallNational Medal of Technology Laureate Epstein Distinguished Professor of ECE

Purdue University

Why isn’t there a global scale hydrogen energy economy?

• Small volume energy density

• High pressure gas and low temperature liquid storage expensive and dangerous

• Hydrogen transport dangerous and expensive

Solution: use a safe, cheap, earth-abundant high energy density material for storage and transport that can react with water to make hydrogen on demand

Is there such a material? Yes! It’s ALUMINUM!It’s ALUMINUM!

If aluminum could split water the chemistry would be:

2Al + 6H2Al + 6H22O O 3H 3H22 + Al + Al22OO33:3H:3H22OO

Aluminum has the highest volumetric energy density of anything on the chart and a higher mass energy density than ethanol, methanol or bituminous coal!

Mass Energy Densities of InterestMass Energy Densities of Interest

• • As As hydrogenhydrogen from splitting water: from splitting water: • • 1 Kg H1 Kg H22: 142 MJ = 39.4 kWh combustible energy: 142 MJ = 39.4 kWh combustible energy

• • 1 Kg Al makes 111 g of H1 Kg Al makes 111 g of H22 from 2 Kg of H from 2 Kg of H22O = O = 4.4 kWh4.4 kWh

• • 1 gal (10 Kg) Al makes 44 kWh as hydrogen1 gal (10 Kg) Al makes 44 kWh as hydrogen • • 1 gal. diesel: 37 kWh 1 gal. diesel: 37 kWh • • 1 gal. liquid hydrogen: 10 kWh 1 gal. liquid hydrogen: 10 kWh

• • As As heatheat from splitting water: from splitting water: • • 1 Kg Al: 1 Kg Al: 4.4 kWh4.4 kWh • • Total energy, 1 Kg Al: 8.8 kWh (1Kg coal: 6.7 kWh!)Total energy, 1 Kg Al: 8.8 kWh (1Kg coal: 6.7 kWh!)•• Energy to electrolyze alumina to 1 Kg of Al: Energy to electrolyze alumina to 1 Kg of Al: 12.9 kWh12.9 kWh•• Total energy efficiency: (8.8/12.9) x 100 = Total energy efficiency: (8.8/12.9) x 100 = 68% 68% • • HH2 2 energy efficiency: (4.4/12.9) x 100 = energy efficiency: (4.4/12.9) x 100 = 34%34%

Technology sustainability & large scale useTechnology sustainability & large scale use

World Supply:World Supply:

• Al “reserve” in the planet’s crust: about 1013 Kg (as Al); 1.2 x 1012 Kg of H2 made by splitting water = 5 x 1013 kWhrs of H2 energy

• Current worldwide annual Al production: 32 billion Kg from bauxite; • 400 billion Kg of scrap impure impure elemental Al; amount needed to supply 12% US annual energy consumption of about 100 quad BTU. Since all Al that is converted to an oxide can be recycled back to metallic Al via electricity from any source, Al is a global scale alternative energy storage material with almost no carbon footprint.

WHAT CAN WE MAKE?WHAT CAN WE MAKE?• Buy scrap or metallurgical grade, i.e. cheap, Al, melt it with Ga and Sn, then cool it to make solid, “bulk like” Al rich alloys up to 93 wt% solid Al grains, and 6.2 wt% Ga, and 0. 8 wt% Sn liquid in the grain boundaries that splits any kind of liquid water, e.g. sea water, dirty water and polluted water, at between 20 C and 100 C and make H2, heat, including superheated steam, on demand and aluminum hydroxide powder• Buy 95% Al, 5% Sn vendor alloy, contact with a liquid mixture of 7 wt% Ga and 1 wt% Sn, and then with water; this splits any kind of liquid water at temperatures between 20 C and 100 C and make H2, heat, including superheat steam, on demand and aluminum hydroxide powder • Recover/separate inert Ga and Sn from hydroxide powder and recycle indefinitely

A sample of Al-GalInSn* splitting waterA sample of Al-GalInSn* splitting water

Using scrap Al and recovering the GaInSncomponent, the cost/kWh ofour hydrogen/comparedto other fuels:

Coal: $0.004 Natural Gas: $0.06 Al: $0.10 Gasoline: $0.09 (at $3.00/gallon) Li ion battery: $4.00

*GaInSn is liquid at room temperature

2Al2Al(GaInSn)(GaInSn) + 6H + 6H22O* 3HO* 3H22 + 2Al(OH) + 2Al(OH)33 + GaInSn + GaInSn

3H2 + 3/2O2 3H2O; we get back half the water when we use the H2;we get rest of the water + the Al back via smelting; the GaInSn is inert

* Including salt water

2 Al(OH)3 + heat Al2O3 + 3 H2O + electricity 2 Al

Bottom line: You get all the water back as potable water!Bottom line: You get all the water back as potable water!

Legend: = Aluminum

= Ga-In-Sn

= Hydroxide

= Hydrogen gas

Al-Ga grain

Alloy Water

At room temperature, the Ga-In-Sn phase is liquid! The solid Al “grains” are able to dissolve into and move freely through the liquid phase. Al near the surface contacts the water interface. The ensuing exothermic reaction produces hydrogen as the Al is oxidized. This reaction proceeds until all the Al grains split the water into hydrogen gas and aluminum hydroxide

How it works!

Abundance: Al: crustal abundance – 8% Ga: crustal abundance – 0.002% Sn: crustal abundance – 0.0002%

Sustainability: Al: annual production – 32 billion kg Ga: annual production – 184 million kg Sn: annual production – 165 million kg

Therefore, as long as the Ga and the Sn are recycled there is no Ga abundance or productionproblem

Energy Source(wind, solar, nuclear, geothermal, etc)

(-12.9 kWh/kg-Al)

Energy Source(wind, solar, nuclear, geothermal, etc)

(-12.9 kWh/kg-Al)

Application(fuel cell, combustion engine)

Application(fuel cell, combustion engine)

WaterWater

Aluminum Alloy

Aluminum Alloy

Aluminum HydroxideAluminum Hydroxide

Heat(+4.4 kWh/kg-Al)

Heat(+4.4 kWh/kg-Al)

EnergyEnergy

WaterWater

Reaction

Hydrogen(+4.4 kWh/kg-Al)

Hydrogen(+4.4 kWh/kg-Al)

The Aluminum-Hydrogen CycleThe Aluminum-Hydrogen Cycle

CO2 Sequestered

CO2 Sequestered

Example applications:Example applications:Replace batteries with a Ga-Al-H20/fuel cell system for high energy density electric power applications:

• • emergency/stand-by power (AlGalCo)emergency/stand-by power (AlGalCo)• • electric wheel chairs, golf carts, utility vehicleselectric wheel chairs, golf carts, utility vehicles• • PDAs, Laptops, etc. PDAs, Laptops, etc. • • hybrid and fuel cell powered carshybrid and fuel cell powered cars

• • Stirling enginesStirling engines• • replace gasoline for HEVs (GM Volt) replace gasoline for HEVs (GM Volt) • • liquid fuel multiplier, e.g. diesel enrichmentliquid fuel multiplier, e.g. diesel enrichment• • trains, boats, ships, subs, truckstrains, boats, ships, subs, trucks• • large boats and other maritime applicationslarge boats and other maritime applications• • off-grid/remote power + desalinated/potable water!off-grid/remote power + desalinated/potable water!• • integrated utilities with solar farms/wind turbinesintegrated utilities with solar farms/wind turbines

Other applications:

• Enabling Wind or Solar as Base Load Electricity Generation Capacity– Target cost: $0.10/kWhr, assuming 40x alloy

recycling– All required technologies are known– Primarily an Engineering Development Project– Enables Environmentally Sound and Secure

Electricity

reaction tank,95-5 alloy, andcontrols

H20

H2, 4.4 kWh/Kg-alloy 24/7 or on demand

Fuel Cell or GasTurbine/Generator

H20

ElectricityElectricity

Heat, 4.4 kWh/Kg-alloy24/7 or on demand

Steam Turbine

alumina, Ga,In,Sn + H20

component separationH20

Ga,In,Sn recoveryalumina electrolysis12.9 kW-Hrs/Kg Al

95-5 alloyregeneration

intermittent intermittent electrical power, e.g. electrical power, e.g.

solar or windsolar or wind

Enabling Wind or Solar as Base LoadEnabling Wind or Solar as Base LoadElectric Power Model Flow DiagramElectric Power Model Flow Diagram

CONSUMER

CAN BE DONE FOR $1/GAL OF WATER AND $0.34/kWh OF ELECTRICITY

ALUMINUM!

• A GLOBAL-SCALE, EARTH-ABUNDANT, HIGH ENERGY DENSITY STORAGE MATERIAL FOR SPLITTING ANY KIND OF WATER TO MAKE HYDROGEN, HEAT AND POTABLE WATER ON DEMAND

• ONCE YOU BUY IT, IT IS YOURS FOREVER;UNLIKE FOSSIL FUELS IT STAYS IN THE ENERGY SYSTEM.

THE BOTTOM LINE: