Originally Posted by Peter J
If we must go "Carbon Free" then batteries are the least energy dense, which is why cars carry half a tonne or so of dead weight.

I was surprised at the energy density of Liquid Ammonia, it seems it can be converted in fuel cells.
Interesting article here...

https://www.frontiersin.org/articles/10.3389/fenrg.2014.00035/full



Yes, there's lots of work going on with ammonia:

https://www.sciencedirect.com/science/article/pii/S0360128517302320

https://www.ammoniaenergy.org

And another interesting fuel is iron:

https://phys.org/news/2018-09-iron-powder-alternative-fuel-industry.html

TM Factory Visit 2019 - https://bit.ly/4mLbmG9

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