David
Lu

The Kid Who Noticed the Sky

June 2012. David Lu steps off a plane in the San Francisco Bay Area, eighteen years old, arriving from Shanghai. He doesn't reach for his phone. He looks up. The sky is blue - unnervingly, almost aggressively blue. He had never seen it that color before. Not with that kind of clarity. Not without the gray particulate haze he had grown up treating as weather.

That wasn't a metaphor. That was the whole product.

A year later, Lu returned from a trip to Beijing with a sore throat. He was by then a sophomore at UC Berkeley studying atmospheric science - a degree that sounds like what you choose when you've already decided to spend your life thinking about what's in the air. He started asking a question nobody had a good answer to: why is accurate air quality data so expensive, so sparse, and so slow? The monitors that governments relied on cost hundreds of thousands of dollars each. You'd deploy a handful per city. A handful per city to cover millions of lungs.

In 2014, Lu and his co-founders - Paolo Micalizzi (CTO), Baljot Singh (VP Hardware), and Meiling Gao (COO) - started Clarity Movement Co. through UC Berkeley's CITRIS and Banatao Institute. They wanted a sensor that cost a fraction of the incumbent hardware, worked anywhere - solar power, cellular connectivity - and could be deployed in under five minutes. What they built looks like a tissue box. What it does is map the invisible.

A Tissue Box That Changed London's Emission Zones

The Clarity Node-S is solar-powered and cellular-connected. It measures particulate matter, nitrogen dioxide, ozone, carbon monoxide, and more - seven pollutants in total. It talks to the cloud automatically. It costs a fraction of a traditional reference monitor. You put it on a pole, a roof, a school fence, and it starts sending data.

London took notice. The Breathe London project deployed over 450 Clarity sensors across the city, generating the kind of hyperlocal air pollution data that hadn't existed before - not at that density, not at that cost. That data directly informed policy decisions around London's expanding Ultra Low Emission Zone. When a city changes what vehicles it allows on which roads, it helps to know what the air actually reads at street level, block by block.

The LA Unified School District came next, deploying more than 200 outdoor Clarity sensors across its campus network. Then Singapore. Then the Philippines. Then 85 countries' worth of deployments, adding up to over 500 million individual measurements. That's a lot of chess pieces on a board that used to be invisible.

Before Clarity: Greenpeace and the Fossil Fuel Fight

Before Lu was building sensor hardware, he was a Greenpeace intern running the North American Arctic Campaign. He also led UC Berkeley's Fossil Fuel Divestment Campaign - student environmental activism at its most organized and confrontational. He was trying to move institutions with protest and persuasion.

What he found, over time, was that his instincts ran toward the data problem underneath the political problem. You can argue about air quality. You can also measure it, make the measurements irrefutable, and hand them to policymakers, school districts, and city councils who can't argue with a graph.

Running the Company

Lu is methodical in a way that runs counter to startup mythology. He doesn't glorify chaos. He organizes each day into three tiers of tasks: must-do, day-to-day, and nice-to-do. He's calendar-driven. He runs intentional team meetings. He thinks marketing and PR belong in the founder's job description, not delegated away when there's product work to do.

After board meetings, he goes hiking. Not as a metaphor - physically, into the hills, backpacking. Nature is both the subject of his company's work and his personal pressure valve. He comes back, he says, with mental clarity restored. The man who built a business around measuring the air also uses the air to reset.

His favorite management principle comes from John Doerr: "If you can't measure it, you can't manage it." For a person who founded a company because nobody was measuring the right thing, that one lands.

The Funding Story

Clarity Movement raised its $9.6M Series A+ in August 2022, co-led by Amasia and the Active Fund, with participation from Spero Ventures, SOSV's HAX program, Launch Fund, and The Climate Syndicate. Total funding stands at $16.2M. The company had by then proven the model at scale across 60+ countries - the round was about acceleration, not survival.

Career Timeline

What TIME Saw

In October 2025, TIME added David Lu to its 100 Most Influential Climate Leaders list. The selection wasn't for rhetoric - it was for infrastructure. Clarity had built something that environmental advocates had been asking for for decades: cheap, accurate, dense, real-time air quality data available to governments and communities that couldn't afford the $200,000-per-monitor status quo.

The investor Amasia, which co-led the Series A+, put it plainly in their October 2025 newsletter: the recognition reflected a decade of execution on a problem that the industry had decided was too hard to solve affordably.

The Product Philosophy

Lu's clearest articulation of why Clarity exists: "You are essentially trying to play chess without really seeing the chess board." Air pollution kills an estimated seven million people per year globally. The data that could guide intervention has been locked behind equipment costs that kept it in research labs and wealthy-city monitoring stations. Clarity's play was to collapse that cost and democratize the board.

The Clarity Node-S measures PM1, PM2.5, PM10, NO2, O3, CO, and CO2 depending on configuration. It's solar-powered - no grid connection required. It transmits via cellular - no local network required. It uses machine learning to correct for temperature and humidity interference, which is part of why it achieves the accuracy it does at the price point it does. You can put it in rural India or on a school fence in Los Angeles and it works the same way.

The company's early Optical Particle Counter sensor design was so good that Sensirion - a major global sensor manufacturer - licensed it. That's not a typical outcome for a startup's first hardware generation.

What He's Building Toward

Lu's aspiration is blunt: a world where every person, in every city, on every continent, has access to real-time, accurate air quality data. Not aggregated national averages. Not once-a-day readings from a monitor fifteen miles away. Hyperlocal data - the kind that tells a parent whether it's safe to let their kid play outside, the kind that tells a city which blocks are above the safe threshold and which aren't.

Clean air, in Lu's framing, is a fundamental human right. Currently, it's more accurately described as a function of where you were born and what your city can afford to measure. Clarity is trying to change the denominator on that equation - not by lobbying or protesting, but by making the sensors ubiquitous enough that ignoring the data becomes impossible.

The company is 30 people, $4M annual revenue, and running global infrastructure. Lu still hikes after board meetings. Still uses a three-tier to-do list. Still thinks execution beats originality, every time.

That contrast - Shanghai smog to Berkeley sky - is still the engine. He just built it into a company instead of a memory.