Running studio lights off UPS is not likely. Doing a green-screen virtual studio without decent studio lighting isn't possible (you can't key off green screen lit with houselights...)
You can get reasonable results with retroreflective cloth and a ring of green LEDs around the lens, plus possibly some domestic halogens - cf the BBC Tours 'studio' in the basement of TVC. Some remote studios in places like investment banks use a similar setup, though with slightly more professional key lights.
That said, I'm not sure how suitable it would be for broadcasting - I'd still go for the option of the studio down the road with a more stable power supply.
(incidentally, the power supply at GIR must have been pretty shonky to warrant decamping to 4 Millbank, a building not famed for a reliable power supply.)
Retroflective cloth is OK for down-the-line type studios (the BBC NY single-camera studio uses it). However it needs over/above-camera autocue to work - as you need to run with LED ring lighting for good results.
Not suitable for big news studios - particularly set-ups like ITN's where you also project guide images onto the CSO backdrop.
Yes, See the BBC Birmingham Public Space:
, The autocue is higher than the camera and it means the presenter is not looking into the camera. Interestingly, they use that for breakfast and weekend weather bulletins. They can switch it through to the gallery.
I must admit I wondered where the non MT main studio forecasts came from. I thought they just rigged something up at the back of the newsroom. Never thought they'd actually use the Public Space facillity?
They do, they used to use the back end studio rear project with a green still, but the lighting used to fook it up, so they rigged the Public Space area up. It's only used on weekends as they are recorded at 6am in the morning.
Oh it's such a perfect day, I'm glad I spent it with you...