In 2006, billionaire technology investor John Doerr announced that “green is the new red, white and blue.” He could have stopped at “red.” As Doerr himself said, “Internet-sized markets are in the billions of dollars; the energy markets are in the trillions.” What he didn’t say is that huge, trilliondollar markets mean ruthless, bloody competition. Others echoed Doerr over and over: in the 2000s, I listened to dozens of cleantech entrepreneurs begin fantastically rosy PowerPoint presentations with all-too-true tales of trillion-dollar markets—as if that were a good thing. Cleantech executives emphasized the bounty of an energy market big enough for all comers, but each one typically believed that his own company had an edge. In 2006, Dave Pearce, CEO of solar manufacturer MiaSolé, admitted to a congressional panel that his company was just one of several “very strong” startups working on one particular kind of thin-film solar cell development. Minutes later, Pearce predicted that MiaSolé would become “the largest producer of thin-film solar cells in the world” within a year’s time. That didn’t happen, but it might not have helped them anyway: thinfilm is just one of more than a dozen kinds of solar cells. Customers won’t care about any particular technology unless it solves a particular problem in a superior way. And if you can’t monopolize a unique solution for a small market, you’ll be stuck with vicious competition. That’s what happened to MiaSolé, which was acquired in 2013 for hundreds of millions of dollars less than its investors had put into the company. Exaggerating your own uniqueness is an easy way to botch the monopoly question. Suppose you’re running a solar company that’s successfully installed hundreds of solar panel systems with a combined power generation capacity of 100 megawatts. Since total U.S. solar energy production capacity is 950 megawatts, you own 10.53% of the market. Congratulations, you tell yourself: you’re a player. But what if the U.S. solar energy market isn’t the relevant market? What if the relevant market is the global solar market, with a production capacity of 18 gigawatts? Your 100 megawatts now makes you a very small fish indeed: suddenly you own less than 1% of the market. And what if the appropriate measure isn’t global solar, but rather renewable energy in general? Annual production capacity from renewables is 420 gigawatts globally; you just shrank to 0.02% of the market. And compared to the total global power generation capacity of 15,000 gigawatts, your 100 megawatts is just a drop in the ocean. Cleantech entrepreneurs’ thinking about markets was hopelessly confused. They would rhetorically shrink their market in order to seem differentiated, only to turn around and ask to be valued based on huge, supposedly lucrative markets. But you can’t dominate a submarket if it’s fictional, and huge markets are highly competitive, not highly attainable. Most cleantech founders would have been better off opening a new British restaurant in downtown Palo Alto.