Ūrja (Urja) was one of the Saptarṣi (Saptarshi; the seven legendary sages) in Svārociṣa (Swarochisha) Manvantara. He was the son of Maharṣi (Maharshi; Great Sage) Vaśiṣṭha (Vasistha).

Vāyupurāṇa(62.16)
Brahmāṇḍapurāṇa (Maharṣi)(1.36.17)
Viṣṇupurāṇa(3.1.11)
Matsyapurāṇa(67.4)