Rising to a height of 40 m against the skies of Manchester, the 'Tower of Light' by London-based firm Tonkin Liu is a biomimetic edifice that serves as a stark white addition to the city skyline near its historic centre. Besides its role as an enclosure for flues that extend from a new low-carbon energy centre in the city, the structure was envisioned as a "landmark gateway project" for the Manchester Civic Quarter, supplementing the Civic Quarter Heat Network (CQHN) and Energy Centre, which supply low-carbon water and power to prominent civic buildings in the heart of the city. At its base, in proximity to the Greater Manchester tramway and Manchester Central Station is the 'Wall of Energy' - a tessellated street façade enclosing the new energy centre, clad in an interlocking lozenge-shaped tile assembly that evokes rippling impressions left by ocean waves in the sand. 

Tonkin Liu was commissioned to design the structure after having emerged as the winner of an architectural competition held back in 2017. The designers reflect on the brief in a press statement, mentioning that "the competition sought a creative and cost-effective design with significant architectural merit." In approaching this stipulation, the architects were inspired by themes of rotation and energy, as exemplified by the motion of the Sun and the Earth. With these concepts in mind, they proceeded to redefine the brief as a place-specific intervention in the form of a tower structure accompanied by a sculptural wall.

Explaining the influences they drew from in devising the tower component of this scheme, the architects note, "Manchester’s own industrial skyline provided lessons in the expression of the decorative furnace towers that rise from a robust base into a tall, slender shaft and a celebratory summit. Inspiration from nature also came from the Cholla desert cactus that grows as tall as possible, its vertical form minimising solar exposure, and its tall shaft pointing directly at the midday equatorial sun." Alternatively, the origins of the wall’s visual expression came from the dynamic movements of the earth, the rhythmic structures of beehives - a reference to Manchester’s emblem - as well as the terracotta exterior of the city’s iconic Midland Hotel.

From these precedents, Tonkin Liu envisaged a single surface structural design as the best option for the tower, melding structure and art into one - a contrast to the double layered configurations of most flue towers. This solution would also optimise the usage of construction materials, by virtue of its relatively light and thin profile. For this purpose, Tonkin Liu resolved to make use of their pioneering 'Shell Lace' structural system - devised in association with Arup, merging advanced digital modelling, analysis, fabrication, and the principles of tailoring. Earlier versions of this system were used by the firm in bridge designs across the UK, Portugal, and China, to name a few. In order to adhere to the geometry of the site, they also devised an oval-plan form for the tower.

The final structure, which is the largest of its kind built using a Shell Lace system, was crafted from flat steel sheets, with thicknesses varying between 6mm - 8mm, that were tailored, laser-cut, and finally, welded together. These were rolled, stitched, and welded into pairs that were then fixed along the vertical plane to the base, forming a sequence of eight 4m x 6m x 3m transportable drums. Finally, the drums were assembled on site using bolted connections. Featuring undulations that interlock in a stiff lattice, the resulting façade design, embodying lightness, is reminiscent of a pillar whose 'flutes' have been articulated as an intricate filigree in pure white.

Comprising a base, middle, and crown, the corrugations along the surface of the tower’s design define a diagonal lattice whose undulations form ridges that are oriented to moderate the effects of prevailing winds, delivering them down and around the tower. Evolving patterns of perforations introduced on the surfaces of the sheets, help break the flow of the wind and eliminate trailing eddies through vortex shedding. "The Shell Lace Structure technique allows the form and composition of the tower to be highly expressive of its structural performance," shares the design team.

On the other hand, the Wall of Energy follows the arcing path of the site boundary beneath an arched tramway bridge, extending for 63 metres, with a height that varies between four to six metres. As the Combined Heat and Power (CHP) engine and boilers for the energy centre are accommodated under the transport for the Greater Manchester tramway, the wall itself hosts a ribbon window to grant passers-by a sneak peek of the centre’s inner workings. The firm collaborated with Darwen Terracotta in prefabricating the modules constituting the tiled wall, which numbered 1373 in total and featured 31 different tile variations. "To make a sculptural whole from many smaller units, digital tools of design, and construction were employed. The search for form was focused on how the horizontal quality of the wall could work in contrast to vertical expression of the tower, reflecting light and casting shadow," relays Tonkin Liu. Morphing from a flat surface at the bottom to a curving sinusoidal profile at the top, the wall’s surface exhibits numerous undulations throughout its course, with a feature wall explaining the façade’s functionality.

"Minimal energy is used to illuminate the Tower of Light and Wall of Energy. During the day, mirrored gold finished stainless steel reflectors within the tower ripple in the wind, reflecting the sunlight into the depth of the tower’s chambers, filling the tower with a moving kaleidoscope of light,” shares the firm about the lighting design elements in the project. They add, “During the night, as dusk sets in, integrated LED lights create a programmed light sequence, directed at the Tower of Light’s reflectors and the Wall of Energy. Tonkin Liu’s collaboration with lighting specialist SEAM Design developed pre-programmed sequences every quarter of an hour, marking the passage of time.” The tower’s exterior will also be illuminated with colours on landmark dates to mark festive celebrations.

Tonkin Liu concludes, "The completed Tower of Light and Wall of Energy form a holistic energy landmark that engages communities with the innovative technologies at the heart of Manchester’s low-carbon ambition and Climate Change Action Plan. Together, they create a beacon on the skyline and on the street, an integrated interactive, enduring, and animated symbol for our times.”

Project Details

Name: Tower of Light and Wall of Energy, Manchester Civic Quarter Heat Network & Energi Centre
Location: Lower Mosley Street, Manchester, United Kingdom
Year of Completion: 2021
Client: Manchester City Council
Art, Architecture, Landscape: Tonkin Liu
Main Contractor & Operator: Vital Energi
Project Architect: Matthew Burnett
Structural Engineering: Arup
Project Engineer: Chris Clarke
Lighting Design: SEAM Design
Steelwork Fabricator: Shawton Engineering Ltd
Façade Contractor: Axis Envelope Solutions
Ceramic Tile Manufacturer: Darwen Terracotta
Planning Consultant: Turley
Lighting Supplier: Tryka UK
Lighting Programming: ECS Limited
Lighting Installer: ProGen