If your Prima Luna is 300 watt, it's on 13 hours a week, assuming electricity costs 35p per kWh then that's about £1.37 a week plus your standing charge, plus all the other bits of kit you have turned on.
I am all electric including an ASHP in a detached 4 bed bungalow in an exposed location with twin valve monoblocks, I burn 7000kWh annually so that's 7000x0.35=£2450 plus a couple of hundred standing charge. So my total is £2650/12=£221 per month
Hope that helps
Analogue
401 / PU7 / AT33ev
Longdog Audio Quartz turntable PSU
Longdog Audio MCJ1 - Prototype Phonostage
Digital
Innuos Zen Mini Mk 3
Topping D50s
Caiman Seg & Dorado
Cambridge CXC
Amps
Tron Seven Linestage
Bel Canto Set 40 or Nick Gorham built 300B Set Monoblocks
Speakers
Tannoy GRF Memory.
Tannoy ST100.