Off topic rambling
I did some napkin math. I've seen that electricity price cap in the UK is 0.28£ per kWh (I used this source).
One would need about 1.786 kWh to achieve an additional cost of 0.50£, which, at 50W, would take around 35 hours and 40 minutes.
I'm wondering how you can squeeze over 35 hours of Factorio in a day.
If you manage to squeeze 5 hours of Factorio every day (which is a LOT once one has a job), one day of Factorio on Windows would cost around 7p per day. Just having a second laptop costed you so much more that it would take shy of 10 years to compensate for it (with current electricity price I reckon).
[Edit] I read somewhere that the x64 emulation on the M1 totally rocks, what kind of performance (both UPS wise and electricity wise).