One advantage of lockdown has been time to get caught up on long-standing ‘background’ projects. For Rob that has meant the chance to complete the power study of Les Mis that he’s been carrying out gently in the background since the start of the year.
The project started with a question: how much power are we actually saving by moving our lighting to LED? This came partly out of the Save Stage Lighting campaign of a few years ago, trying to persuade the EU that while we wanted to keep the magic of tungsten light available to us we weren’t stuck on old technology and were actively moving to more efficient sources. And partly just out of curiosity: intuitively we know newer rigs are using less power than older ones, but exactly how much? We know that a new LED light uses less power than an equivalent tungsten light, but we also know it’s less bright, so we run it at a higher level. In show use, it doesn’t use as much less power as you’d think from just reading the label…
Fortunately Rob already had a tool in place to analyse this - the PowerTrack function in his FocusTrack show documentation software. What was harder to find was one show lit using older (tungsten, arc) equipment, then re-lit by the same designer to look the same using newer (LED) equipment. But a conversation with lighting designer Paule Constable suggested the new production of Les Misérables might provide such a case study, the rig having evolved over the years with, in the new London production, all of the tungsten lighting fixtures replaced with LED.
The Les Mis team were able to supply all of the data for three versions of the show. The result is an in-depth look at three versions of the show’s rig, with detailed comparisons of the moment-by-moment power use and then the overall energy use. The end result confirms we are now using less power than before. The surprise: not as much less as we might have hoped!
The article can be found in the current issue of LSi: [link]