Relighting—Museum Ara Pacis

In honor of Emperor Augustus, who had victoriously returned to Rome, the Roman Senate commissioned a magnificent marble altar in 13 BC. The provinces had been pacified following decades of civil war and the Pax Augusta promised stability and prosperity. The deeds of the celebrated ruler and his family, vividly and three-dimensionally depicted on the enclosing walls of the Ara Pacis Augustae, were intended to become a model for the citizens of the empire. Since 2006, the Altar of Augustan Peace, one of Rome's most important ancient monuments, is housed and can be admired in the Museo dell'Ara Pacis in the vicinity of banks of the Tiber. The airy building designed by Richard Meier + Partners includes areas for temporary exhibitions in addition to the large glazed hall with the altar.

A total of 218 LED lighting tools from ERCO now illuminate the museum and its central exhibit of the ancient altar in new light. The aim of the conversion from halogen lighting to contemporary LED illumination was, in addition to improved energy efficiency, to increase the quality of visual perception of the monument and the associated spatial experience. The original lighting concept, based on the idea of 'positive contrast', was retained: it not only uses nuanced levels of brightness to create perceptual hierarchies between the exhibit and surrounding space, but also builds up additional contrast through the use of different color temperatures. General lighting with a warm white light color defines the space around the Altar of Augustan Peace. Carved entirely of Carrara marble, the monument itself is set clearly apart from its surroundings thanks to the powerful directional lighting with a neutral white light color.

An impressive spatial and artistic experience due to nuanced lighting

The tour through the museum leads from the entrance hall through a corridor into the main exhibition hall with a height of about 12.50 meters. A row of Lightcast recessed luminaires (32W LED/3000K) provides the general lighting for the axis of movement. Parscan spotlights (24W LED/3000K) with flood distribution (28°) and Parscan wallwashers (24W LED/3000K) make the special dimensions of the room perceptible through uniform vertical illumination of the walls, whilst simultaneously emphasizing their quarrystone surfaces of fine Roman travertine.

Parscan spotlights with narrow spot distribution (6°) and an 8W LED module set precise beams of light on a row of ancient busts marking the transition into the main hall.

85% energy savings: relighting with maintenance-free ERCO LED luminaires

In the exhibition hall with the altar, Parscan spotlights (24W LED) with a warm white light color of 3000K and spot distribution (16°) provide general lighting. The sacrificial altar itself, enclosed by four walls, is illuminated by Parscan spotlights (8W LED) with neutral white light color of 4000K and narrow spot distribution (6°). This directional accent light creates an expressive interplay of light and shadow on the ornate marble reliefs and enables the depicted figures to be emphasized in a sculptural way.

A specific challenge for the lighting design in the central hall around the Altar of Augustan Peace was the changing daylight that enters through skylights and through the two fully glazed sides of the building.

With the help of sensors and Casambi Bluetooth control, the new lighting now responds accordingly: light intensity is regulated in such a way that the marble reliefs on the exterior surfaces of the altar are optimally illuminated, with the monument standing out against its surroundings in a radiant white. In addition, further pre-defined light scenes can be called up depending on the season, time of day and use of the museum.


All Parscan spotlights with LED were mounted on existing ERCO track, which kept installation effort and costs low. The new lighting system with ERCO LED lighting tools, commissioned by the City of Rome and generously sponsored by Bulgari, represents a sustainable investment. Maintenance-free and with a long service life, its connected load is only 8.4 kW compared to the 57 kW of the old system, which means it consumes around 85% less energy.