Clean technology can be a dirty phrase. Often, venture capitalists won’t invest because they’ve been burned in the past, as many clean tech startups haven’t been sustainable (pun intended), and frankly, no company has really taken hold of the entire industry by storm.

But there are some great leaders in the cleantech sector — from scientists, to technologists, to investors, to entrepreneurs — and they’re making real impacts during a time when renewable energy finally has gained some momentum and startups are focusing more on their environmental efforts.

Here are eight important leaders — some pioneers, some newbies — in the clean technology sector to know about.

1. Dr. Ruihong Zhang

Dr. Ruihong Zhang, a researcher at UC Davis, invented the Renewable Energy Anaerobic Digester, which captures methane (biogas) and turns it into electricity. She has won many awards in the fields of clean technology and bioenergy, and her technology is now worth millions of dollars and is utilized by startups that want to tackle problems like waste production. Earlier this year, the university decided to use it for their on-campus waste.

2. Sarah Kearney

Sarah Kearney created Prime Coalition, which helps private companies invest in energy-related startups. Kearney founded it after serving on several energy boards at MIT and other companies. It is a nonprofit, and it helps philanthropists find investment opportunities that address climate change. Really, it’s trying to make philanthropy more like venture capital.

3. Billy Parish

Billy Parish is the founder and CEO of Mosaic, a crowdfunding platform for solar energy. Mosaic has gotten a lot of press this year, and has really propelled the rooftop solar movement forward in California. Parish has been working in clean energy for years — he dropped out of Yale to found Energy Action Coalition and was named a “Climate Hero” by Rolling Stone Magazine. Mosaic, for him, is a business opportunity and a scalable way to address climate change.

4. Miles Barr

A few years ago, Miles Barr started Ubiquitous Energy, which developed ClearView Power technology, allowing surfaces like the backs of electronic devices (such as an iPhone) or window glass to transform into solar panels. The tech is starting to catch on as an option to use surfaces other than roofs to generate solar power, and Barr was recently named one of MIT’s innovators under 35.

5. Lyndon Rive

Lyndon Rive is the co-founder and CEO of SolarCity, probably the most well-known solar provider. The company has recently made many acquisitions in all areas of the supply chain for solar power, and has moved into manufacturing and solar loans, making it the leader in solar power companies and an example of a really successful one.

6. Emily Cole

Emily Cole is the co-founder of Liquid Light, which uses electrochemistry to convert carbon dioxide to industrial chemicals that can be used productively. This helps companies reduce their carbon footprint while helping reduce their waste stream to landfills by turning the trash into fuel and other chemicals, and giving them low-cost chemicals to use if they need. Cole is the chief science officer, and according to MIT, the startup is trying to make ethylene glycol, which is a chemical used to make plastics, as early as 2017.

7. Ian Monroe

Ian Monroe is the founder and CEO of Oroeco, an app that tracks your carbon footprint by using to track your purchases and where they came from. It turns carbon tracking into a game — and rewards you for lessening your footprint. But beyond that, Monroe is trying to crowdsource information about investment companies by looking at their environmental policies and carbon footprints. The startup is working with some finance world partners (Confluence Capital and Trucost) to launch a new type of fund called diversified exchange traded funds (ETFs) that look at climate and financial performance. Monroe is also a lecturer at Stanford, where he teaches about climate change decision making and energy processes.

8. Lisa Jackson

Lisa Jackson is the VP of environmental initiatives for Apple. She’s gotten quite a bit of attention as of late, but it’s for good reason. Jackson has set an example for environmental efforts at big tech companies, and the company itself has become a leader for tech giants by committing to 100% renewable energy in their data centers and starting to work toward lessening their supply chains’ carbon footprints. Before Apple, Jackson was the EPA administrator from 2009 to 2013.

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