A dazzling performance

Prince Charles famously described the National Theatre as “a clever way of building a nuclear power station in the middle of London without anyone objecting”. And indeed, architect Sir Denys Lasdun’s modernist vision has generated its fair share of controversy since construction began back in 1969.

Its Brutalist raw concrete exterior may not be everyone’s idea of structural splendour: pretty it certainly ain’t. Yet it makes for an arresting addition to London’s South Bank, and few would disagree that accentuating what historian Mark Girouard referred to as the building’s “aesthetic of broken forms” would prove a worthy challenge for any lighting designer.

When Philips Electronics announced a five-year lighting partnership programme with the National Theatre, the object was to replace the landmark venue’s external and internal lighting schemes with state-of-the-art, energy-efficient designs.

Although the first phase of the interior revamp is not set for completion until this summer, the public have already witnessed dramatic results at the completed external illumination scheme’s switching-on ceremony, which was hosted by Ken Livingstone and actress Zoë Wanamaker.

Philips’ LEDs have been used throughout the exterior phase. They replace the former scheme, the majority of which used less-than-efficient 70 W and 150 W metal halide lamps.

Philips’ creative director Rowena Preiss, who designed the display, says: “The energy savings are massive at around 40-50%, with payback on the £100 000 project expected within one year. In addition, LEDs also require far less in the way of maintenance.”

Architectural sensitivity and audience enhancement were crucial to the enterprise.

Preiss explains: “The theatre is grade II-listed, so English Heritage has always been concerned about the luminaires on display. Because LEDs are so much smaller than other types of lighting, they are discreet and don’t ruin the line of the architecture.”

In-house electrical project manager Kieron Lillis agrees.

“With the banners on the exterior of the building, we had to hide a lot of the new LEDline Philips products so they couldn’t be seen, and we had to liaise with English Heritage and Lambeth Conservation to make sure anything we did to the exterior of the building was concealed.”

He adds: “Where we already had fittings in the pavement, we had to use these supplies, but we had to install a number of new ones. And it wasn’t just the fittings themselves – we also needed to conceal the cables as much as possible.

“So we had to hide cables in conduits and spray cables that were the same RAL colour as the flagpoles they were going onto. In some cases, it was challenging and certainly time-consuming, but we’re used to it with this type of building.”

What English Heritage thought of the rather flamboyant colour selections is debatable. Crucially, LEDs offer a great deal of choice when it comes to tints and tones, and the design team has created an impressive variable palette.

“Aesthetically, we’re trying to encourage younger people to take more of an interest in the theatre by using a vibrant, arresting lighting scheme,” says Preiss.

The plan is for the lighting scheme to remain white, unless the theatre is running a special event or performance. With the regular programme, the lighting comes on automatically each evening at one hour before sunset and goes off again at 1.30am.

However, the possibilities are impressive. “Our in-house engineers can link the DMX signal up to a range of preset programmes and make the lighting change colour automatically at various times of day, or plug in a lighting desk and do something fancy for a specific event,” explains Lillis.

Key to the design is the illumination of the building’s two flytowers, which have been lit using some 47 RGB LEDline2 1200 mm modules, positioned in three rows to ensure uniform coverage of the vertical plane. LEDline2 was chosen for its slim profile. It creates dimension and shape while avoiding nuisance spill light. DMX controls provide the dynamic colour-changing effects.

Impressively, Philips’ lighting technology is set to deliver a 70% reduction in the energy required to illuminate the flytowers.

Emphasis was also given to the building’s imposing lift cores. Led by Lillis, the installation team created upward shafts of coloured light using a mix of LEDline2 modules and LED Beamer fittings. The latter are compact yet powerful, which helps the building retain its artistic integrity, while adding a flamboyant, modern edge.

You have to think of the knock-on effects. We won’t have to relamp it later, as we’ve chosen leds. We won’t have to go through the landfill process

The scheme incorporates a single Luxeon high-power LED and is designed for projection over distances of up to 30 metres. The LED Beamer used within the cores also incorporates Solgel filter technology, which saturates the stone façade in rich blue tones.

It was also important to provide a sense of arrival for visitors attending shows at the theatre itself. Guiding theatre-goers to the main entrance are a series of illuminated columns that showcase posters of the latest productions on offer. Lillis’ team positioned LEDline2 modules at the bottom of each structure, with the light directed upwards.

Angled columns along the side of the theatre were lit using a combination of LED Beamers and Mini Decoflood luminaires, which allow directional lighting to flow along the building line, complementing its form. The flagpoles, which are set at intervals along this pedestrian avenue and emblazoned with the bold National Theatre logo, were also lit using LEDline2 modules. In this case, the modules were smartly concealed within the poles themselves.

The in-house team carried out the installation in conjunction with electrical contractor PIP Electrical.

“It was too much for the in-house team to take on board without PIP’s help, as we were allotted such a short timeframe,” says Lillis. “It was only about four weeks, and it was all pretty hectic. Even with PIP providing extra labour, we sometimes had to work overnight due to restrictions, which meant we weren’t allowed to work above roadways in the day.

“Equipment such as large cherry-pickers also had to be hired when we were putting in some of the high-level lighting. But we got things finished on time, and we’re on track for the interior stage.”

Lillis admits that the theatre still has a few problems to overcome before it attains its overall exterior energy-saving target of 40-50% reductions.

“For instance, our flytowers were lit with various 2 kW and 1.8 kW lamps. We haven’t been able to change all of these yet, because we’re waiting for the new generation of Philips Luxeon LEDs to come out later in the year,” says Lillis.

Londoners are also set to experience a new video wall installation on the roof of the building this spring. The old dot Seefact bulb system is being replaced by a full-colour LED panel displaying messages.

“At the moment, the high-level display is quite an old sign, and we have to get the lamps from Mexico as it’s the only place they’re made now. It also takes a hell of a lot of power,” says Lillis.

“On the new display we’re putting in there’ll be 70% less electricity used, which will amount to a £9600-a-year saving. But you also have to think of the knock-on effects. We won’t have to relamp it later as we’ve chosen LEDs, and as we don’t have to dispose of the lamps, we won’t have to go through the landfill process.”

The focus has now switched to the interior and backstage areas. Public areas will be fitted with low-energy, high-efficiency fittings, as will the vast network of corridors, workshops and rehearsal rooms.

“In the foyers, we’re hoping to make big savings as we currently have a lot of 50 W capsule lamps and 70 W metal halides that are to be replaced with LED lighting,” says Lillis. “We are also hoping to replace a number of 575 W lamps with 70 W Philips energy-saving metal halide lamps, which we’ll be fixing into existing fittings,” he adds.

The team has already refurbished one of the theatre’s bars, removing a 50 W halogen capsule downlighter and putting in a series of 7 W Philips compact LED downlighters.

“We had to increase the number, because LEDs don’t give you the same amount of light as halogens. Even so, we’re making some, albeit small, energy savings,” he says.

And it’s not just the luminaires that are undergoing a revamp. The foyer houses 29 toilets, which are currently lit on a constant level for 19 hours per day. The new interior lighting design, however, includes PIR sensors for these areas. Rear-of-house sections such as staircases, which have 24-hour lighting for security, are also to benefit from movement detection, dimming down to 10% at times when they are not in use.

By the end of 2008, the National Theatre aims to have saved 20% of its overall electricity consumption.

“Through the Philips project, we’re expecting to save about £48 000 by the end of the year, although the figures are not set in stone, and that’s if the new technology we’re waiting for comes out,” admits Lillis.

Whether pinning your hopes on a product that hasn’t even been introduced onto the market yet is forward-thinking or just plain reckless remains to be seen. But if ever a building was worthy of such a cutting-edge lighting scheme, it’s this one.