Zilusa d’ shabbos and uvda l’chol are totally, 100% subjective phenomena. Your rebbe’s psak shows that Rav Elyashiv agreed more or less with Rav Shlomo Zalman’s psak on electricity.
In all honesty, while I don’t operate electricity on shabbos, I honestly know that this is a fixture of convention, rather than any actual halakhic concern.