Cooling Cities from above
Making Earth habitable for humans, profitably.
We already geoengineer: every forest cleared, every barrel burned. It's time to shift from accidental to intentional. The next great companies will manage habitability on purpose, measuring, metering, and monetizing cooler cities.
Phoenix hit 31 consecutive 110°F days in 2023.1 People died. The grid strained. AC, already 50–70% of summer electricity in hot cities,2 made urban cores even hotter. Over 1,300 died at Hajj in 2024.3 Paris, designed to never need air conditioning, now shuts down during heat waves.
Oil companies sold energy extraction, but were really selling geo-engineering. They just didn't call it that. The trillion-dollar companies of tomorrow will sell geo-engineering proudly—for global benefit.
The category winner will own the default service contract for keeping cities livable. Power savings alone is a $50B+ opportunity. Climate services, $1T+. The opportunity is to build the utility.
High-altitude platforms at ~20km deploy variable-area reflector film, sending controlled sunlight back to space. Immediate, measurable, and fully reversible.
Each unit unfurls reflector film roughly the size of three football fields (~16,000 m²), reflecting a controllable slice of sunlight. Typical operation delivers 1-2°C peak-hour zone cooling.
Stratosphere (~18-22km), above weather. Units stitch passes over service polygons for dwell time people feel at ground level. Solar-powered, autonomous navigation.
No aerosols, no chemistry: just light reflected back to space. Switch off in hours. Public telemetry. Reversible by design.
We'll fly whatever clears the safety and economics bar. Current baseline modeling uses high-altitude balloon platforms, but the architecture supports gliders, ribbons, or hybrid approaches. The physics is the same; the vehicle is an engineering choice.
Sundial competes with gas peakers, batteries, and new peak capacity: not midday PV. We target the worst 50-200 hours per year: late-afternoon peaks in heat waves, when grids are maxed and operators are paying premium prices for the last slice of firm capacity.
If this category is going to exist, the only defensible version is one that can be turned off fast, measured in public, and held accountable. That's the design constraint.
Platforms retract in hours, not days. No persistent atmospheric chemistry. Switch off and the effect stops. Full stop.
Real-time position, deployed area, and local observations published openly. Anyone can verify what we're doing, where, and when.
Third-party measurement and verification built into every contract. Ground sensors, satellite data, open methodology.
Platform loss is contained—no runaway effects, no persistent residue. Aviation coordination via FAA/ICAO. Spectrum and overflight compliance from day one.
Climate intervention isn't hypothetical: it's already happening. The question is whether it happens responsibly.
Launching sulfuric aerosols and moving the Overton window on climate intervention. Credit for starting the conversation—we think precision and reversibility matter too.
$50M+ in venture funding for cloud seeding with AI targeting.4 China and Dubai scaling similar programs.
Precise, measurable, reversible. Public telemetry. No chemistry: just reflected light. Reversible, predictable, priceable.
At 118°F, Phoenix peaks near 17 GW,5 mostly air conditioning. Studies suggest ~180–200 MW saved per 1°C.6 Cooling and data centers are driving exponential growth in electrical demand, creating grid crises worldwide. We can build negawatts in the sky faster and cheaper than a new gas turbine and new powerlines.
Modeled economics. Based on public grid data and explicit assumptions. Cooling efficacy is the key uncertainty; early validation work focuses on coupling factors and controllability.
Grid contracts ($108M) + premium services ($54M) from events, stadiums, and data centers.
How blocked sunlight becomes avoided megawatts: the physics of negawatts.
Shade doesn't generate power: it avoids demand. Negawatts settle like any grid resource: capacity contracts, DR programs, non-wires alternatives. The utility avoids building peakers; we share the savings.
Exploratory, contingent on engineering validation.
Premium event coverage. Guarantee WBGT reduction over 10×10 km windows for concerts, sports, outdoor gatherings. Parametric pricing based on delivered degrees.
Seasonal capacity contracts with utilities and municipalities. Public dashboards, independent M&V, settlement like any other demand response resource.
Future tier: multi-state coverage for agricultural regions, interstate corridors. Long-term contracts with regional transmission organizations.
Whoever scales a high-altitude cooling network first can own the market for regional climate services. The first mover will have both a cost advantage and an installed base that a latecomer can't replicate.
One atmosphere per city. First mover cools everyone; duplication is uneconomic. Early partnerships with utilities and regulators lock in long-term service agreements.
With an 85% learning rate,7 a first-of-a-kind (FOAK) platform at $5M reaches ~$350k at 100k units and ~$200k at 1M units. Each doubling of production drives costs down 15%.
More units mean finer control and better data. Service improves as the fleet grows. A network effect that boosts performance with scale.
Flight hours compound into better control algorithms. Regulatory firsts set the operating standard. The data advantage grows with every hour in the air.
Start with a constellation of reflectors that can moderate district-level heat. Scale to peak-heat management across our hottest cities. Eventually, a planetary thermostat.
Engineer solution to premium wedge economics, deploy a HeatShield Zone for a major event or mega-district. Prove reliability, safety, and outcomes.
Target cities where peak MW is expensive and heat-driven. Contract seasonal peak relief and heat-alert cooling.
Scale fleet across multiple cities, seasonally redeploying across hemispheres. Drive down unit costs through manufacturing learning.
The long-term vision: climate infrastructure across major hot cities worldwide. Platform enables broader albedo management.
Interactive model defining the design space for shade economics. Adjust platform costs, fleet size, and revenue assumptions to explore what's viable from premium events to planetary scale.
Explore the model
The full narrative arc: from mycelium materials to atmospheric infrastructure. How finding leverage points led from mushrooms to shade.
Watch on YouTubeWe're looking for the engineers of Spaceship Earth.