The First Hydrogen Water Heater

rinnai.co.nz

2 pointsplumeria3 comments

"New Zealand presently does not have the infrastructure to supply 100% hydrogen through the existing pipe network, which means that we will be unable to launch our hydrogen water heaters until the infrastructure is ready." Apparently hydrogen is not easily distributed via regular gas pipes, due to leakage.

They seem to be promoting a water heater that uses a heat pump [1], which purportedly saves up to 75% of the energy bill [2]. I think this seems more viable in the short term.

[1] https://rinnai.co.nz/blog/water-heating/what-is-a-hot-water-...

[2] https://rinnai.co.nz/water-heating/hot-water-heat-pump/hot-w...

Distributing hydrogen via pipelines is not advisable. Nor is storing hydrogen containers inside buildings.

There's a thing called the gas explosion concentration range (or other similar names). Natural gas can only explode within quite a narrow range of concentrations in air. Hydrogen has a very wide range.[1] Hydrogen is also a small molecule, so it escapes from pipes and containers very readily.

1. https://www.engineeringtoolbox.com/explosive-concentration-l...

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