03/11/2025
Sika and its newly acquired company, Elmich, collaborated with Singapore Polytechnic and Sembcorp Solar to develop a pioneering Smart Solar BlueGreen Roof (i.e., a Smart BlueGreen Roof with Solar Panels).
The Smart Solar BlueGreen Roof incorporates VersiDrain® BST, a modular, self-watering green roof tray system designed to collect and distribute rainwater efficiently while creating convenient maintenance pathways.
A pilot installation was carried out on the rooftop of Teaching Block 20 (Level 5) at Singapore Polytechnic. It featured three sections demonstrating three different roof types: a Bare Concrete Roof, a Concrete Roof with Solar Panels, and a Smart Blue-Green Roof with Solar Panels.
This breakthrough was officially unveiled at BEX ASIA 2025, held from 3 to 5 September at Marina Bay Sands Expo & Convention Centre.
At the booth, visitors experienced a real-time monitoring system that captured data from sensors tracking solar panel temperatures, electricity generation (kW), roof surface/floor temperatures, irradiance (sunlight intensity), classroom temperatures without air conditioning, and tray water level. The system also streamed a live video feed of the pilot installation, bringing the project to life on the exhibition floor.
Preliminary test results demonstrated promising outcomes for the Smart BlueGreen Roof with Solar Panels
Solar Panel Energy Efficiency
The Smart BlueGreen Roof with Solar Panels recorded lower solar panel
temperatures and higher electricity generated than the Concrete Roof with Solar
Panels (55°C vs 60°C). The temperature reduction is likely due to the
evapotranspiration of the greenery layer beneath the solar panels. As solar panels
operate more efficiently at lower temperatures, electricity generation
increased.
Cooler Roof Surfaces
The floor temperature beneath the Smart BlueGreen Roof with Solar Panels was cooler than the Concrete Roof with Solar Panels (27.5°C vs 38°C). This 10.5°C reduction demonstrates how greenery beneath solar panels can effectively cool roof surfaces
Reduced Indoor Temperatures
Classrooms beneath the Smart BlueGreen Roof with Solar Panels were cooler than those beneath the Concrete Roof with Solar Panels (31°C vs 33°C). This shows the potential of integrating greenery with solar panels to improve indoor comfort by reducing heat transfer from the roof.
Plant Sustainability & Flood Control
Even under high irradiance (intense sunlight), the water level in the BlueGreen Roof Trays’ reservoir was maintained at 98.8%. This is likely due to the following factors:
- In addition to misting and sprinkling irrigation, the plants can draw water from the BlueGreen Roof Trays’ reservoir through geotextile capillary wicks.
- The Smart BlueGreen Roof also has passive and active discharge functions to support flood control management.
We look forward to strengthening our partnership with Singapore Polytechnic and scaling this impactful, sustainable solution to local projects across Singapore.
Discover Sika Solutions for Urban Greenery and Landscaping.