Make room for rain.
See how rooftop storage works, how forecasts and network capacity shape release decisions, and how collected water can cool hot roofs.
Start here · Guided interactive story Make room for rain. Keep water when it matters.Explore normal storms, long rainfall events, coordinated releases, roof cooling and neighborhood-scale impact in one guided presentation.
Start the interactive story →Replay real Vienna weather
Run March–October 2024, 2025 or 2026 hour by hour. Watch stored rainwater, storm preparation, and roof cooling with adjustable playback speed.
Start the historical replay →Neighborhood water cycle
Sunny garden use → storm forecast → controlled release → rainfall stored in tanks. Includes a no-tank comparison.
Open animation →Three-day storm control
A 120 mm example with three rainfall pulses, stress-aware hold decisions, and safe-release windows.
Open animation →Impact at scale
Explore 0–50% roof participation with conservative, ambitious and highly optimistic scenarios. Compare rooftop runoff with and without storage in a hypothetical 1 km² neighborhood.
Open calculator →100 tanks. One sewer.
Compare all-at-once drainage with a fleet coordinator that rotates and throttles releases across three drainage zones.
Open animation →Rainwater roof cooling
Rain fills a storage tank. During very hot weather, stored water is pumped onto the roof, where evaporation helps cool the surface.
Open animation →Cost and site feasibility
Explore which buildings are easiest to retrofit, compare nominal storage costs with a Vienna storm basin, and estimate optional rainwater or tap-water roof cooling.
Open cost calculator →The experiments we want to run
One host house and an optional separate PV test: measure indoor cooling, stormwater control, solar generation, deposits, reliability and real-world costs.
Explore the proposed pilot →Tap-water roof cooling
See the same roof-wetting and evaporation principle using a direct tap-water supply.
Open animation →