SPLITTING ANY KIND OF WATER WITH GLOBAL-SCALE, EARTH-ABUNDANT, LIGHT, RECYCLABLE METALS TO MAKE HYDROGEN, HEAT AND ON DEMAND POTABLE WATER ON DEMAND Jerry M Woodall National Medal of Technology Laureate Epstein Distinguished Professor of ECE Purdue University

Why isnt 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 Its ALUMINUM! Is there such a material? Yes! Its ALUMINUM! If aluminum could split water the chemistry would be: 2Al + 6H 2 O 3H 2 + Al 2 O 3 :3H 2 O

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 Interest As hydrogen from splitting water: As hydrogen from splitting water: 1 Kg H 2 : 142 MJ = 39.4 kWh combustible energy 1 Kg H 2 : 142 MJ = 39.4 kWh combustible energy 1 Kg Al makes 111 g of H 2 from 2 Kg of H 2 O = 4.4 kWh 1 Kg Al makes 111 g of H 2 from 2 Kg of H 2 O = 4.4 kWh 1 gal (10 Kg) Al makes 44 kWh as hydrogen 1 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 heat from splitting water: As heat from splitting water: 1 Kg Al: 4.4 kWh 1 Kg Al: 4.4 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: 12.9 kWh Total energy efficiency: (8.8/12.9) x 100 = 68% Energy to electrolyze alumina to 1 Kg of Al: 12.9 kWh Total energy efficiency: (8.8/12.9) x 100 = 68% H 2 energy efficiency: (4.4/12.9) x 100 = 34% H 2 energy efficiency: (4.4/12.9) x 100 = 34%

Technology sustainability & large scale use World Supply: Al reserve in the planets crust: about Kg (as Al); 1.2 x Kg of H 2 made by splitting water = 5 x kWhrs of H 2 energy Current worldwide annual Al production: 32 billion Kg from bauxite; impure 400 billion Kg of scrap 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? 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 H 2, 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 H 2, 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 water Using scrap Al and recovering the GaInSn component, the cost/kWh of our hydrogen/compared to 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

2Al (GaInSn) + 6H 2 O* 3H 2 + 2Al(OH) 3 + GaInSn 3H 2 + 3/2O 2 3H 2 O; we get back half the water when we use the H 2 ; we get rest of the water + the Al back via smelting; the GaInSn is inert * Including salt water 2 Al(OH) 3 + heat Al 2 O H 2 O + electricity 2 Al Bottom line: You get all the water back as potable water!

Legend: = Aluminum = Ga-In-Sn = Hydroxide = Hydrogen gas Al-Ga grain AlloyWater 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 – % 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 production problem

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) Water Aluminum Alloy Aluminum Hydroxide Heat (+4.4 kWh/kg-Al) Heat (+4.4 kWh/kg-Al) Energy Water Reaction Hydrogen (+4.4 kWh/kg-Al) Hydrogen (+4.4 kWh/kg-Al) The Aluminum-Hydrogen Cycle CO 2 Sequestered

Example applications: Replace batteries with a Ga-Al-H 2 0/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 vehicles electric wheel chairs, golf carts, utility vehicles PDAs, Laptops, etc. PDAs, Laptops, etc. hybrid and fuel cell powered cars hybrid and fuel cell powered cars Stirling engines Stirling engines replace gasoline for HEVs (GM Volt) replace gasoline for HEVs (GM Volt) liquid fuel multiplier, e.g. diesel enrichment liquid fuel multiplier, e.g. diesel enrichment trains, boats, ships, subs, trucks trains, boats, ships, subs, trucks large boats and other maritime applications large 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 turbines integrated 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, and controls H20H20 H 2, 4.4 kWh/Kg-alloy 24/7 or on demand Fuel Cell or Gas Turbine/Generator H20H20 Electricity Heat, 4.4 kWh/Kg-alloy 24/7 or on demand Steam Turbine alumina, Ga,In,Sn + H 2 0 component separation H20H20 Ga,In,Sn recovery alumina electrolysis 12.9 kW-Hrs/Kg Al 95-5 alloy regeneration intermittent electrical power, e.g. solar or wind Enabling Wind or Solar as Base Load Electric 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: