Half of them hire steam iron becoming irritated to find this device uses a lot of electricity (9,6)

I believe the answer is:

immersion heater

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'this device uses a lot of electricity' is the definition.
'immersion heater' can be an answer for 'device' (I have seen 'Electrical device' mean 'immersion heater' so perhaps 'device' could also mean 'immersion heater'). I'm not certain of the rest of the definition.

'half of them hire steam iron becoming irritated' is the wordplay.
'half of' suggests halving the letters.
'becoming irritated' indicates an anagram.
'them' halved is 'em'.
'em'+'hire'+'steam'+'iron'='emhiresteamiron'
'emhiresteamiron' with letters rearranged gives 'IMMERSION HEATER'.

'to find' acts as a link.

Can you help me to learn more?

(Another definition for immersion heater that I've seen is " Electrical device".)

I've seen this clue in The Irish Times.

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