🌡️ Why this matters — Urban Heat Island
+2.7°C
Hyderabad LST rise 2015–2024
50°C+
Projected Indian city temps by 2035
18.7M
Buildings mapped across 30 cities
40%
Urban heat absorbed by buildings
Every building that goes up without green cover adds to the Urban Heat Island effect. VertiGreen identifies which buildings contribute most to UHI at individual building resolution using real satellite data. Nobody has done this at 18.7 million building scale for Indian cities before.
🏗️ What this tool does
VertiGreen is a building-level geospatial analysis tool that:
• Maps solar heat exposure per wall using sun position mathematics (6am–8:30pm full-day weighted)
• Calculates shadow analysis to identify which walls are naturally shaded — and therefore best suited for vertical gardens
• Estimates Land Surface Temperature using NASA MODIS satellite data (1km resolution, daily updates)
• Predicts cooling impact of vertical gardens using physics-based LAI, albedo and evapotranspiration models
• Calculates rainwater harvesting potential using IMD annual rainfall data and NBC 2016 runoff coefficients
• Checks bylaw compliance against National Building Code 2016 FAR limits
🛰️ Data methodology & limitations
"LST and NDVI values are sourced from NASA MODIS satellite data where available. In cases of API unavailability, values are estimated using a physics-based model calibrated to Indian climatic zones. Greening impact predictions use LAI, albedo and evapotranspiration factors from published literature (Pérez et al. 2011, Alexandri & Jones 2008)."
Land Surface Temperature (LST) Real when availableEstimated as fallback
Source: NASA MODIS MOD11A1 (1km resolution, daily). When NASA API is unavailable, LST is estimated from latitude + season + urban density formula calibrated to Indian cities.
NDVI Vegetation Index Real when availableEstimated as fallback
Source: NASA MODIS MOD13A2 (1km, 16-day composite). When unavailable, estimated from 0.05–0.25 based on urban density. Used to correct wall heat exposure for surrounding vegetation.
Wall Temperature Approximate
Calculated as: LST + (wall_exposure × 15). The ×15 multiplier is approximate — real values depend on wall material, colour, orientation and albedo which are not available in building footprint data.
Greening Cooling Effect Research-based estimate
LAI factor −35%, albedo factor −15%, evapotranspiration −20% — from published ranges (Pérez et al. 2011). Not building-specific measurements. Actual cooling varies by plant species, coverage density and climate.
UHI Offset Rough approximation
Estimated as: 3 + wall_exposure × 3. Real UHI measurement requires weather station data and neighbourhood-level density analysis not yet integrated in this version.
Solar Azimuth & Shadow Mathematically precise
SunCalc algorithm — peer-reviewed solar position formula. Shadow polygon = building height / tan(solar altitude) in the direction opposite to sun azimuth. Accurate to ±1° for Indian latitudes.
Wind Direction & Speed Live data
Source: Open-Meteo API (free, no key). Real-time wind from nearest weather station. Diurnal pattern (calm dawn → peak midday → calm night) applied based on thermal convection science.
🏛️ Government schemes — where this tool fits
🏙️
AMRUT 2.0 — Urban Greening Component
₹66,750 crore scheme with explicit urban greening mandate. VertiGreen can identify high-impact buildings for targeted subsidy allocation rather than random distribution.
🌆
Smart Cities Mission
100 cities, active greening budget. Building-level heat maps from VertiGreen can directly feed into Smart City project planning documents.
🌳
CAMPA Funds — Compensatory Afforestation
Vertical greening on buildings could qualify as urban forest equivalent. VertiGreen provides the data to make that case building by building.
🏗️
RERA & NBC Compliance
If NBC 2016 mandates green walls for new construction above 10 floors, VertiGreen becomes a compliance verification tool. Already checks bylaw height compliance.
💰
Cost reality of vertical greening
Installation: ₹800–2,500/sq ft. Typical 100m² wall: ₹8–25 lakhs. Annual maintenance: ₹1–3 lakhs. Government subsidy of even 40% would unlock widespread adoption in metro cities.
📖 References
• Pérez G. et al. (2011). Green vertical systems for buildings as passive systems for energy savings. Applied Energy.
• Alexandri E. & Jones P. (2008). Temperature decreases in an urban canyon due to green walls and green roofs in diverse climates. Building and Environment.
• IMD (2023). District-level rainfall normals 1991–2020. India Meteorological Department.
• BIS (2016). National Building Code of India. Bureau of Indian Standards.
• Wan Z. (2014). New refinements and validation of the collection-6 MODIS land-surface temperature/emissivity product. Remote Sensing of Environment.