Lecture on Hydrogen as an Alternative Fuel Source

Introduction

• Hydrogen as an alternative to fossil fuels in transport
• Investment by companies and nations
• British Science and Technology Committee's skepticism
• Hydrogen: Hope or hype?

Basic Chemistry of Hydrogen

• First element of the periodic table
• Combustion with oxygen yields water and energy
• Potential for driving motors or turbines with water as the only exhaust

Practical Challenges

• Hydrogen is a gas, requires compression for storage and transport (700 bar pressure)
• Energy per liter: 1/6 of gasoline; energy per mass: ~2x gasoline
• Hydrogen-powered cars are heavier than gasoline-powered ones

Technology of Hydrogen Fuel Cells

• Around for 200+ years; first fuel cell by William Grove (1939)
• 1960s: General Electric's proton exchange membrane innovation
• Usage by NASA: Gemini spacecraft, Apollo missions, space shuttle, ISS

Adoption and Market

• Hyundai and Toyota selling hydrogen-fueled cars for a decade
• Plans by BMW, Ford, and other automakers
• Government initiatives in Scotland, Germany, etc.
• Global sales in 2021: 16,000 hydrogen cars, 3,500 in the US
• EU's Re-Power EU strategy to replace 10% of gas consumption with hydrogen
• Investment by countries like Japan, Canada, Egypt, China, and the USA
• Green Hydrogen International's project in Texas (Hydrogen City)
• Microsoft's interest in hydrogen fuel cells for data centers

Sources and Production of Hydrogen

• Hydrogen is abundant but not in a pure form on Earth
• Methods of production: separation from water/methane requires energy
• Color scale of hydrogen production:
  • White: Rare, naturally occurring
  • Black/Brown: From coal/lignite, emits CO2 and methane
  • Gray: From methane and water, emits CO2 and methane
  • Blue: Like gray, but CO2 stored underground (1% current production)
  • Green: From renewable energy (solar, wind)
  • Pink/Purple: From nuclear power

Environmental Impact and Cost

• Gray hydrogen: 550 g CO2 per kWh
• Blue hydrogen: 486 g CO2 per kWh
• Green hydrogen: Ideally 1/4 emissions of gray, but real-world data lacking
• Wind and solar methods inefficient and expensive
• Nuclear power might be an option
• Infrastructure costs for hydrogen fueling stations

Water Usage and Cold Start Problem

• Water supply for hydrogen production (2% irrigation water)
• Cold start problem: water freezing degrades fuel cells
• Solutions: preheating systems

Rare Metals for Fuel Cells

• Platinum and iridium required; rare and expensive
• Limited supply from South Africa, Russia, Zimbabwe
• Supply issues as demand increases

Material Challenges

• Hydrogen embrittlement: makes storage tanks brittle
• Heavy and expensive tanks needed
• Practical handling issues (e.g., breakdown of filling stations)

Conclusion

• High carbon footprint from current methods of hydrogen production
• Real-world data on climate impact lacking
• Economic challenges in competing with fossil fuels
• Infrastructure and rare metal supply constraints
• Overall, hydrogen is not a panacea for climate change

Additional Notes

• Mention of NordVPN as sponsor for data privacy