Welcome to Extensible Energy

Headquartered in Berkeley, California, Extensible Energy was founded in 2010 by John Powers, an energy economist and software entrepreneur, and Ari Halberstadt, a solar software architect and engineer. 

Our mission is to promote the expansion of the commercial solar market through developing intelligent software that is always adapting with energy, technology, data, and the grid.



Co-founder & CEO

Experienced entrepreneur; 25+ years of energy experience: utilities; energy consulting; economist, MA

Director of Engineering

15 years software architecture experience: software architect, Agile trained, NRG Home Solar software engineering, energy resources engineer, MS

Technical Buildings and Control Expert

10 years HVAC Design & Engineering experience including: modeling and controls engineer, Model Predictive Control, Mechanical Engineering PhD

Co-founder & CTO

20 years of software and energy experience: software engineer & cloud computing architect; solar energy expert, MS/MBA

Director of Products

10 years clean energy product and finance experience: solar+storage product development, venture capital, investment banking, MS

Engineering Team

Software Engineer

Experienced software developer and systems architect

Software Developer and Data Analyst

Backend and machine learning developer

Data Scientist

Efforts include Antarctic neutrino experiments, gamma-ray-burst observatories in the US, a Kuiper belt observatory in Taiwan, and HIV experiments in San Francisco.

Software Engineer

Fullstack developer with over 15 years of experience

Communications and Finance


20+ years CFO for venture backed companies, 15 years of Commercial Real Estate; JD

Product Manager


Content and Partnerships Manager

25 years experience with partnerships, marketing, branding

Business Partnership Manager



Our Values


When it comes to load flexibility and demand charge management challenges for solar and storage, we will always  be improving our solutions.


Our software and services are always easy to install and nearly invisible. Customers should only notice us when they see how we’ve reduced their utility bills.


Our software is adaptable in real-time, and so are we. We’ll happily adapt to new technology, rates, markets, policies, and opportunities.


You can trust us to deliver on our promises. Whatever we do, we’ll always make it right.


We are energetic, always moving forward, always improving, always looking for new opportunities to deliver more.


Data is good. Harnessing and using data improves our products, our business, and our vision for transitioning the world to 100% clean energy.

Extensible Energy Careers

If you are passionate about buildings, solar, and load flexibility and have skills to contribute to our team of energy industry disrupters, contact us.


We are always hiring. If you believe you would be a good fit for our team please get in touch. 

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2120 University Avenue Berkeley CA 94704

© 2020 by Extensible Energy.