Hydro-Plantéa Atrium.

The project began with a provocation: how can we breathe new life into a historically significant, abandoned site while reimagining its role within the community?

The Thames Iron Works — built in 1837 and famous for constructing HMS Warrior, the world’s first iron-hulled armoured warship — closed in 1912 and has since evolved into an unmanaged habitat hosting over 180 plant species. Our task was to design a bio-integrated system for this site that generates energy, supports local ecology, and creates usable public space — all with minimal human maintenance.

Surrounded by water on three sides at the mouth of the River Lea, the Thames Iron Works sits within an area rich in arts, culture, and ecology — but underserved in workspace and community infrastructure. Field research confirmed that the site’s few open cafés already function as informal offices and social hubs, pointing toward a clear opportunity for a green co-working programme.

Environmental analysis covered wind patterns, solar exposure, rainfall distribution, and the existing ecology of Bow Creek Ecology Park. These datasets fed directly into the parametric roof geometry and cell distribution strategy that follows.

The core innovation is the Hydroponic Biophotovoltaic (HBPV) cell. Conventional BPV systems use organisms like moss to generate small amounts of electricity through photosynthesis. Our approach uses hydroponic plants whose root systems host cyanobacteria — microorganisms that release electrons as a metabolic byproduct — captured by an anode–cathode electrode system submerged in the nutrient solution.

The cell went through six major iterations, balancing electrical performance, plant health, fabrication feasibility, and structural integrity. Early versions explored organic, branching forms but proved too complex to fabricate reliably. The final design simplified the geometry while maximising electrode contact area and providing side-mounting brackets for maintenance access on the rooftop structure.

Physical prototyping combined CNC-machined aluminium moulds, 3D-printed components in PLA and TPU, and hand-fabricated elements. The cell container was CNC-scribed onto 2 mm aluminium sheet, cut with a jigsaw, and finished with lever shears. Electrode assemblies were integrated into 3D-printed housings designed for maximum microbial contact surface.

Material exploration extended to bacterial cellulose — grown in custom silicon moulds cast from 3D-printed positives — as a potential bio-compatible cell interior. Sheets were formed over TPU moulds and dried to create thin-walled containers, demonstrating a path toward fully bio-derived cell housings.

Open-circuit potential (OCP) was measured on a benchtop rig running IviumSoft against an Ivicycle C2000 potentiostat. Three plant species — Syngonium, Maranta, and Hedera — were characterised across single-cell and three-cells-in-series configurations. Single cells reached up to 50 mV; three in series produced a 24-hour peak of 136.7 mV.

The whole shape of the roof was determined by calculation, not by gesture. Working in Grasshopper against the site’s solar-radiation, wind, rainfall, and access-pathway data, the roof was generated through a parametric pipeline that started from the site footprint and ended in a single defensible form.

HBPV cells are mounted in tile clusters: each tile holds 18 cells (6 cells across 3 medium tiles), and the tile is suspended on a lifting column that houses electrical wiring, battery storage, nutrient distribution, and bio-acoustic sensors. The lift mechanism raises individual tiles for plant maintenance without disturbing the surrounding canopy. Bio-acoustic sensors positioned between cells monitor local wildlife; the electricity to run them comes from the cells themselves.

The atrium as it would sit in the site’s real urban context — riverside on the south, preserved warehouses on the north, the existing tree cover absorbed into the programme rather than removed. The intent: a building that reads as a continuation of the existing ecology, not as an arrival placed on top of it.