The top 21 startups to watch that are disrupting the energy industry - Business Insider

VCs flooded the clean-tech industry with nearly $10 billion in 2019, according to PitchBook. It's the second-highest investment sum in a decade.While investors are betting big on clean tech, only five startups have reached unicorn status, with a valuation of $1 billion or more, according to PitchBook and reporting by Business Insider. Here are the 21 startups with the highest valuations, based on data from PitchBook, Crunchbase, and our reporting. We didn't include startups that focus on electric vehicles (EVs), EV infrastructure, or biofuel production.Click her to subscribe to Power Line, Business Insider's weekly clean-energy newsletter.Click here for more BI Prime stories.Around 2008, clean tech was declared dead. Over the next year, venture investments in the industry tumbled.Now, the industry is bouncing back. According to data from PitchBook, global venture capital (VC) funding in 2019 neared $10 billion, after hitting $14.1 billion in 2018.That's great news for the thousands of startups in the sprawling clean-tech industry, which has fusion energy in one corner and carbon capture and utilization in another.

VCs flooded the clean tech industry with nearly $10 billion in 2019, according to PitchBook. It's the second-highest investment sum in a decade.

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But while investors are betting big on clean tech once again, the industry hasn't produced many unicorns — or startups with a valuation of $1 billion or more.Why aren't there more billion-dollar startups？ One possible explanation is a shortage of funding, relative to other industries like healthcare. Another is that clean tech companies don't generate, as one investor calls it, “a network of users.” “In most cases, these companies are not creating the things that cause a lot of social media and other companies to sizzle, which is new networks,” said Tom Blum, a member of the Clean Energy Ventures Group, which funds clean tech startups. “In most cases, you're actually just replacing commodities that already exist.”There are, however, some noteworthy exceptions.Business Insider compiled a list of the most valuable startups in clean tech, based on data from PitchBook and Crunchbase, and our own reporting. The list reveals five unicorns — three of which make batteries — in addition to several startups with a valuation of greater than $400 million. Startups are listed below by their latest post-money valuations, based on data from PitchBook or company comments, except for where marked with an asterisk. The list doesn't include startups that make electric vehicles (EVs) or scooters, EV infrastructure, fuels from biomass, or those that provide services to highly localized markets. Unless otherwise noted, the data come from PitchBook.