Here's some math on that "revolutionary" idea to put things into perspective, as it turns out, it's pretty underwhelming:
- If we used ALL the aluminum produced globally in a year (about 65 million tons), we'd get around 7.30 million tons of hydrogen.
- While that might sound like a lot, it really isn't.. That hydrogen would contain about 8.30 x 10^14 BTUs of energy.
- Meanwhile, our annual global methane production is sitting pretty at 1.14 x 10^17 BTU.
- Doing the math, and our "amazing" aluminum-to-hydrogen process gives us a whopping 0.73% of the energy we get from methane...
And remember, this is assuming we use EVERY SINGLE BIT of aluminum we produce globally!
Obv hydrogen is "cleaner" than gas, but the point is the scale - this method is a drop in the ocean compared to current energy usage.
TL;DR: Using ALL the world's annual aluminum production to make hydrogen would only give us 0.73% of the energy we get from natural gas....
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For the math nerds, here's more detail on the chemistry and energy calc:
- The reaction: 2 Al + 6 H2O → 2 Al(OH)3 + 3 H2
- Global aluminum production: ~65 million metric tons/year
- Molar mass of Al = 26.98 g/mol
- Moles of Al = 65,000,000,000 kg / 0.02698 kg/mol = 2.41 x 10^12 moles
- H2 produced = (2.41 x 10^12 moles Al * 3) / 2 = 3.62 x 10^12 moles H2
- Mass of H2 = 3.62 x 10^12 moles * 2.016 g/mol = 7.30 x 10^12 g = 7.30 million metric tons
BTU Calculation:
- Energy content of H2 = 113,738 BTU/kg
- Total energy from H2 = 7.30 x 10^9 kg * 113,738 BTU/kg = 8.30 x 10^14 BTU
Methane Comparison:
- Annual natural gas production ≈ 4,000 billion cubic meters
- Assuming 80% methane content: 3,200 billion cubic meters of methane
- Energy content of methane ≈ 35,663 BTU/m^3
- Total energy from methane = 3,200 x 10^9 m^3 * 35,663 BTU/m^3 = 1.14 x 10^17 BTU
- Ratio: (8.30 x 10^14) /(1.14 x 10^17) = 0.0073 or 0.73%