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alvah11/05/20252 repliesview on HN

This has always struck me as dumb, as until recently it was far cheaper to use your existing (gas-fired) hot water than to use a resistive element. However, with gas going out of fashion (and already hugely expensive in the Eastern states), and abundant solar PV, the calculus has changed.


Replies

selcuka11/06/2025

The problem is that the first few litres of the water coming from the hot water pipe may be cold or warm. Therefore adding a resistive element is a better solution to guarantee a specific temperature.

seanmcdirmid11/06/2025

Gas (especially just in time) still works well for water heating even if you can use heat pumps for everything else. No sure when that will flip, I assume it will eventually.

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