Greening the cinema: New technologies help exhibitors conserve energy


The world is going more “green” every day. By “green,” of course I’m referring to building construction materials and methods, and energy conservation. This is driven by the desire to save construction and operating costs as well as minimizing carbon footprint, and people wanting to be good stewards of the planet.

Like many other businesses, theatre owners are looking at ways to go green, especially if it saves them money. Methods to do that can be divided into two general areas: ones related to the design and construction of a new theatre; and those related to saving energy and cost through more efficient energy usage.

In the former category, some people are considering “boothless” theatre options, looking to save money by eliminating the mezzanine level in the theatre. This saves in the initial construction cost, but also represents a more green approach because of eliminating ongoing lighting, heating and cooling of that space. My company, Moving iMage Technologies, manufactures lift systems to facilitate boothless theatre designs. Projector lifts can be incorporated into a variety of architectural schemes. However, the primary focus of this article is reducing energy usage.

A way to reduce the energy usage and carbon footprint in any theatre, both old and new, is to simply turn equipment off at night when it isn’t needed. Theatres are typically only in use about twelve hours out of every twenty-four. When theatres had full-time projectionists, it was a simple matter for them to turn off all the equipment at the end of the day since they were right there. One of the aspects of the modern all-digital cinema is that now someone needs to make a special trip to the booth to power equipment on or off. Most theatres today have a policy for staff to do this, but as a practical matter it doesn’t always happen. The projector lamp will be turned off by automation, but everything else often remains on: projector cooling fans, exhaust fans, servers, the audio processor, and all the audio amplifiers.

Even at idle, each audio processor and amplifier may use as much as 120 watts of energy each. That adds up to as much as 700 watts for a typical audio rack. Many theatres are installing more immersive audio systems with even more speakers and amplifiers than usual, which exacerbates the situation. In an auditorium with one of the new immersive audio formats, the audio rack may use as much as one kilowatt of power at idle! That power is consumed twelve hours a day, 365 days a year, for no purpose. Depending on your local electricity cost, this could cost the theatre owner from $4,000 to $6,000 per year for a ten-screen multiplex.

The theatre manager or other theatre personnel can still go around every night turning everything off and turning everything on again in the morning. However, with all the electronic gear for a typical digital theatre, that will take a fair bit of time. It also results in wear and tear on breakers and switches—we have reports from the field of power switches failing from the constant cycling. Of course, there’s also the chance that a switch somewhere might occasionally get missed in the morning, resulting in shows starting with one or more audio channels missing. Or if the exhaust fans haven’t been powered up, the projector could overheat and shut down.

Moving iMage Technologies currently offers a couple of products to address these issues: the IS-20 Power Manager series and the DCE exhaust fan controller series. The IS-20 can switch up to 120 amperes of AC current to supply the projector, server, and audio gear including the sound processor and amplifiers. It can accept the command to power up and down equipment by contact closure, serial communication, or over the network.

The IS-20 includes inrush surge protection to softly apply the voltage, and sequences the six circuits on or off over several seconds to minimize current surges at the building load center. It also includes UL 1449 level-three surge-protection devices to protect delicate equipment from voltage surges and spikes that might come in on the supply voltage.
The device was designed with the intention of supplying an audio rack; however, it’s equally applicable to controlling house lighting, signs or marquee lighting, the concession stand, or any other aspect of the theatre where it’s desirable to automatically power equipment on and off on a daily basis.

In a typical installation in an audio rack, the IS-20 receives the command to power equipment on in the morning with a special cue from the server or automation, and to power off at the end of the day in the same manner.

The basic version of the IS-20 allows on/off control and status reporting via the Internet, but not control of individual circuits—all circuits are either switched on or off. The more advanced IS-20d model allows individual control of each AC circuit, and also allows the user to program specific time delays for each circuit to cycle on or off using a Graphical User Interface. Both models monitor the AC outputs and provide feedback via the Internet if any power circuit has failed.

The DCE series product performs a similar function to the IS-20, but is specifically designed to control the exhaust system for the projector. Projector exhaust fans move large volumes of air. If the fan remains on all the time, it is extracting expensive conditioned air out of the building that must be replaced and conditioned again. In addition to the simple waste of electricity used by the fan when not needed, this compounds the problem by also loading the HVAC system unnecessarily.

The DCE system turns on the exhaust fan when needed for cooling, and turns it off when not needed. It also offers additional functionality—for example, if the ambient air temperature becomes too low, it can turn the exhaust fan on to prevent moisture condensation in the projector. It can also shut down the exhaust in the event of a fire in compliance with fire codes.

The IS-20, IS-20d and DCE products are only the first in a series of new tools being developed by Moving iMage Technologies to create an automated, optimized and, especially, green modern cinema theatre.