Holborn Viaduct, London

The Challenge

Located at the top of a high-rise building in central London, the Holborn Viaduct project combined two different solar technologies: a rooftop BioSolar array and a separate Onyx solar façade.

The rooftop system needed to be integrated with a blue-green roof without compromising its drainage, water-management or vegetation areas. Standard mounting arrangements were unsuitable, requiring custom-made IFPs to support the solar array.

The façade panels were supplied and installed by another contractor, but their electrical connections still needed to be coordinated with the rooftop cabling and inverter locations.

Our Solution

For the rooftop BioSolar system, PV Plus supplied and installed:

• 15 × AIKO 470 W solar panels, providing a total capacity of 7.05 kWp
• 1 × Solis 8 kW inverter
• Custom IFPs supplied by PV Plus and manufactured by Nicholson
• K2 mounting rails
• DC cabling and electrical connections
• System testing and commissioning

For the separate Onyx solar façade, PV Plus supplied:

• 4 × Solis 12 kW inverters
• Extended cabling to the inverter location
• Electrical connections between the façade array and inverters
• Projoy isolation equipment at the required string locations
• Testing of the completed electrical installation

The Onyx façade panels themselves were supplied and installed by others. PV Plus’s responsibility covered the associated inverter supply, wiring and electrical connections.

The Result of the BioSolar Installation in Central London

The completed rooftop array provides 7.05 kWp of confirmed BioSolar capacity and is expected to generate approximately 6.40 MWh of renewable electricity annually. This represents an estimated carbon saving of approximately 1.49 tonnes of CO₂ per year.

These figures relate only to the rooftop BioSolar array because the quantity and capacity of the separate Onyx façade panels were not included within PV Plus’s installation records.

Together, the blue-green roof, rooftop solar panels and solar façade demonstrate how multiple sustainable building technologies can be coordinated on a complex central London development.

Why PV Plus

Holborn Viaduct required specialist knowledge across BioSolar mounting, rooftop PV and façade-connected electrical systems.

PV Plus coordinated custom Nicholson IFPs, K2 rails, AIKO panels and multiple Solis inverters within one carefully planned package. This allowed Dornan to use one experienced solar contractor for the rooftop system, inverter supply and specialist façade wiring.