The Veldras Orbital Power Facility was a large space station that orbited the Romulan homeworld.
Its smaller then Kaur'el Tennahrex but serves as an important role by being a massive power station that produces energy which is beamed down to the planets cities and homes. It contains a network of several linked quantum singularities which it taps for power similar to how Romulan starships use the quantum singularity drive to fuel the vessels. (Last Unicorn RPG module: The Way of D'era: The Romulan Star Empire)