For all the natural & social aspects like water, fire, animals, wind, earth, trees, engineering, sex, day/night, knowledge, maths, strength -- we have certain kind of deity.
Ancient civilization must have knowledge of electricity thanks to thunderbolt. In today's time, we cannot imagine anything without electricity.
Is there any God for electricity (Vidhyut)?
He is the god of the firmament, in whose hands are the thunder and the lightning; at whose command the refreshing showers fall to render the earth fruitful.
In the Vedas, Indra is the king of Svarga (Heaven) and the Devas. He is the god of the heavens, lightning, thunder, storms, rains and river flows.[6] [Wikipedia]
Reference: Hindu Mythology, Vedic and Puranic
To prove this we consider one more context during Dwaparyuga, in Nanda Gaon when Lord Krishna intentionally told everyone to stop worshiping Indra to overcome Indra proudy nature and that led to heavy raining and lightening in Nanda Gaon . But later Lord Krishna saved everyone by taking all the people of Nanda Gaon under the Govardhana parvat.
According to Brihadaranyaka Upanishad:
कतम इन्द्रः कतमः प्रजापतिरिति । स्तनयित्नुरेवेन्द्रो यज्ञः प्रजापतिरिति । कतमः स्तनयित्नुरित्यशनिरिति । कतमो यज्ञ इति । पशव इति ॥ ६॥
6. "Which is Indra and which is Prajapati?" asked Sakalya. "The thunderclap is Indra and the sacrifice is Prajapati." "Which is the thunderclap?" "The thunderbolt." "Which is the sacrifice?" "The animals."
Another translation from Vedanta Spiritual Library:
III-ix-6: 'Which is Indra, and which is Prajapati?' 'The cloud itself is Indra, and the sacrifice is Prajapati'. 'Which is the cloud?' 'Thunder (strength).' 'Which is the sacrifice?' 'Animals'.
In the book of Adi Shankaracharya Bhashya on Brihadaranyaka Upanishad by Gita press Gorakhpur, the Sanskrit word स्तनयित्नु is taken as विद्युत्
So, Indra is equated with Vidyut i.e Indra is the deity of cloud, thunder and electricity.
Well, Indra is certainly associated with the thunderbolt but he is more a God of Rain and Thunder rather than of electricity. The proper god for this role could be one of the sons of Agni known as Pavaka.
The Vayu Purana Chapter 29, Progeny of Agni mentions the following:
1-2. A mental son of Brahma was the deity identifying himself with Agni (the Fire-god) in the Svayambhuva Manvan- tara. Svaha bore to him three sons: Pavaka, Pavamana and §uci or Saura (solar- fire).
The Hindi text of Vayu Puran uses the word Vaidyut for him:
The Shatapatha Brahmana 2.2.1 also sort of corroborates the same by saying:
That other (practice) then is altogether erroneous. For when Agni passed over from the gods to men, he bethought him, 'I must not pass over to men with my whole body!'
He then laid down in these (three) worlds those three bodies of his. That 'blowing (pavamâna)' form of his he laid down on this earth, that 'purifying (pâvaka)' one in the ether, and that 'bright (suki)' one in the sky. Now the Rishis then existing became aware of this: 'Agni has not come to us with his whole body,' they said. They then prepared those oblations for him.
Now when he makes offering to Agni Pavamâna, he thereby obtains that form of his (Agni's) which he laid down on this earth; and when he makes offering to Agni Pâvaka, he thereby obtains that form of his which he laid down in the ether; and when he makes offering to Agni Suki, he thereby obtains that form of his which he laid down in the sky: and thus he lays down the entire Agni unmutilated. For this reason also he should take out the oblations subsequent (to the full-offering).
Hence, I feel Pavaka, the son of Agni, seems a more likely candidate for being called the god of electricity while Indra could be like an overlord who makes use of his powers via the thunderbolt.
