April 1, 2021

FREMONT, Calif. — APRIL 1, 2021 — Propelled by growing concerns about electric grid reliability, lithium battery safety, and long charging times for electric vehicles, SepiSolar today announced the results of a six-month search for next-generation EV battery systems. The winner: rechargeable alkaline batteries.

The global alkaline battery market, valued at over $17 billion, is poised for year-over-year growth of nearly 10 percent due to a long cycle life, low cost, and proven hazard-free performance. You can also buy replacements at the neighborhood pharmacy or have them delivered in the mail.

SepiSolar has partnered with leading original equipment manufacturers on electrical system design for rechargeable alkaline batteries for electric vehicles (RABEVs). In Q2 2021, SepiSolar will also debut a Center of Excellence for Rechargeable Alkaline Battery Retrofits in Electric Vehicles (CERABREV) at a location near our company offices in Fremont, Calif., a landmark in automotive history since the 1960s.

“When I was a child, I sat behind the wheel of a 12V two-seater and dreamed of traveling cross country in an alkaline battery-powered car. Today’s announcement brings that vision one step closer to reality,” said SepiSolar CEO Josh Weiner.

SepiSolar will use our engineering expertise to maximize stored energy relative to the weight of the vehicle, leading to increased driving range. The team will also explore opportunities to incorporate alkaline batteries, including AA, AAA, and 12V batteries, into the body of the vehicle for improved structural integrity.

Sign up below to attend the CERABREV grand opening and test drive a AA Class vehicle later this year.

Reserve your place now.


Photo by John Holden on Unsplash


December 11, 2018 1

Update: On January 31, 2019, The CPUC unanimously passed this landmark update to California net metering for energy storage. Read SepiSolar’s white paper to see why this change will “super size” solar with storage.

SepiSolar has released a new white paper that reveals significant financial benefits of a California net energy metering policy decision for DC-coupled energy storage

Download White Paper

FREMONT, Calif. –­ Dec. 11, 2018 – A new SepiSolar white paper reveals the financial benefits of a pending revision to California’s net energy metering (NEM) policy. When finalized, commercial DC-coupled solar-plus-storage installations will not only be able to benefit from NEM, but will also be able to increase solar system size, reduce installation and permitting costs, and quicken interconnection approval time.

On Oct. 5, 2018, the California Public Utilities Commission (CPUC) issued a proposed decision to modify CPUC Decision 14-05-033, the NEM tariff policy for solar and energy storage. Once approved, the change will allow DC-coupled energy storage systems to become eligible for NEM without the need for thousands of dollars in extra hardware costs and burdensome verifications required by California utilities and the IRS for AC-coupled energy storage systems.

To take advantage of this policy change, contractors will need to design solar systems with DC-coupled storage and procure DC-coupled energy storage products that incorporate a new Underwriters Laboratory (UL)-verified inverter firmware solution. NEXTracker’s NX Flow™ energy storage system piloted this firmware solution with UL, and is therefore expected to be the first DC-coupled energy storage product approved for the new regulation.

SepiSolar’s white paper reviews and compares the historical challenges of designing AC-coupled and DC-coupled energy storage systems for NEM. It also describes how the new NEM DC-coupled policy and system design will eliminate the need to purchase the extra equipment required for non-export AC-coupled systems, such as reverse-power relays, an additional utility meter, switchgear and a second inverter.

“This policy does more than just reduce equipment costs,” said Josh Weiner, CEO of SepiSolar and author of the white paper. “Businesses can now store their excess solar power in a battery system and receive demand charge benefits as well as the financial benefits from NEM. Another benefit is that solar systems can now be ‘supersized’ to exceed the 1 MW behind-the-meter interconnection soft limit. With a DC-coupled design using products that have the UL-verified firmware, excess generation over 1 MW can now be stored in the battery and later exported into the grid at favorable or optimized NEM or NEM-aggregate tariff. As a simple example, a 1 MW stand-alone solar system can be increased to 2.8 MW with a complementary DC-coupled 1.8 MW storage system and a 1 MW AC inverter that uses the new firmware.”

The same DC-coupled system design may also eliminate the need for utility infrastructure upgrade costs. These costs are most often charged to the solar asset owner when the solar system’s export generation is over 1 MW. Typically, the owner either pays for the upgrades or decreases the system size. With the new DC-coupled configuration, solar-plus-storage systems can be designed to meet the location’s grid capacity, reducing the need for upgrades. Any excess solar can be stored and later exported at up to 1 MW intervals. In models developed by SepiSolar, adding DC-coupled energy storage under the pending NEM policy is usually much less expensive than the cost of grid infrastructure costs without storage.

The simpler DC-coupled design also will allow solar+storage systems to qualify for expedited interconnection, reducing difficult verification requirements for utility interconnection, expediting interconnection. Finally, with the UL-verified firmware, tax equity investors and utilities receive independent verification that the storage system is only exporting solar generation and not charging batteries from the grid. This verification is important for qualifying energy storage systems to receive the 30% investment tax credit.

The proposed CPUC ruling for NEM for DC-coupled solar-plus-storage systems is expected to gain final approval by the end of 2018 or early in 2019.


September 6, 2018 0

Power Technology Magazine interviewed SepiSolar’s CEO Josh Weiner about a new battery net metering policy proposal.

Currently, any energy produced by solar and stored in a connected storage system is not allowed to be exported to the grid for net metering credits, but that’s about to change.

Working with NEXTracker, SepiSolar’s Josh Weiner proposed an inverter firmware solution that, if approved, will allow customers to store solar for self-consumption or export the stored solar power to the grid for the current net metering credit.

Power Technology’s Molly Lempriere explains the reasoning behind the proposal and how solar+battery net metering will be a win-win-win for customers, utilities–and the duck curve. Read the full story here!

Have more questions about solar+energy storage or need a design quote? Contact us.


September 4, 2018 0

Got solar permitting challenges? Recently, Solar Builder Magazines’s editor Chris Crowell interviewed SepiSolar’s CEO Josh Weiner and our project manager, Tiffany Hanson, for “Shadow costs: How outdated local processes stifle the true solar market.

Chris covers an important topic about how jurisdictional red tape can delay projects, add unnecessary “soft costs” and delay a project’s ROI, not to mention delay payments to the contractor.

In addition to interviewing SepiSolar about our 10 years of dealing with solar permitting challenges throughout the U.S., Chris also highlights some solar permitting solutions.

In a case cited by SepiSolar’s Tiffany Hanson, a permit was being denied because the solar panels would be visible from the street. In that case, the solution was already in place because the building was located in California and protected by The Solar Rights Act, which restricts jurisdictions from denying permits due to aesthetic considerations.

There are more examples–and solutions–in the Solar Builder article. Read it here.



July 7, 2018 1


We’re delighted to share the news that SepiSolar’s CEO, Josh Weiner, has been named to Renewable Energy World’s inaugural “Solar 40 under 40” list.

What does it mean to be on the list?

According to Renewable Energy World’s editors, “Solar 40 Under 40 recognizes these individuals and their unparalleled accomplishments within the solar industry. Their mission is to bring solar far into the 21st century and build on the roots of the solar industry and those who have come before them. They are, and will continue to be, advocates for solar. Each one is unique, shows a great deal of passion and has achieved accomplishments within the industry.”

We recently posted a blog about Josh’s solar origin story. It began with Akeena Solar in 2004 and eventually led to founding SepiSolar in 2009.

While growing SepiSolar into a national solar + storage design, engineering and consulting firm with over 6.5 GW of residential, commercial, and utility designs, Josh co-founded Green Charge Networks, managed NRG Home’s engineering department, and has consulted with many solar asset owners and manufacturers on developing and commercializing cost-effective energy storage.

With SepiSolar’s membership in CALSSA, Josh has also been instrumental in developing solar+storage policies that are a win-win-win for utilities, contractors, and solar customers. Josh is also dedicated to educating the next generation of solar PV designers, and has taught advanced solar design courses at UC Berkeley.

If you’ll be attending Intersolar, you can meet Josh in person at Renewable Energy World’s honoree ceremony, Tuesday, July 10, at 3:30 pm on the ees Stage on Level 2; at the Intersolar Tweetup; as well as at our Intersolar edition of Ask SepiSolar Anything.

Congratulations, Josh!


June 26, 2018 2

Intersolar Tweetup

If you’re heading to Intersolar, be sure to meet with “@SepiSolar” and the people behind other solar brands on Twitter at the 8th Annual Intersolar Tweetup!

Intersolar Tweetup-Kiterocket Experience

What’s a Solar Tweetup? It’s a happy hour gathering of all the solar and energy storage people on Twitter. However, instead of limiting conversations to 280 characters, these people get to meet each other in person at a beautiful waterfall setting and actually speak!

Aside from people behind solar brands, you’ll often meet Tweeting solar reporters from Greentech Media, Solar Power World, and PV Magazine, Suncast, and many more.

Whether or not you or your solar company are on Twitter, join us as “@SepiSolar’s” guest! Space is limited, however, so please RSVP! We’d love to see you there.

When: 4:30 pm to 5:30 pm on Wednesday, July 11th

Where: The Samovar Tea Lounge (known as “The Kiterocket Experience” during Intersolar.)

How: Register on Eventbrite to be on the list.



June 21, 2018 1

If you’ve never sat down and had a drink with SepiSolar’s CEO Josh Weiner to get to know him, here’s the next best thing: Listen to his 3-Part Suncast podcast interview with host Nico Johnson.

Nico’s intimate weekly podcast has interviewed solar luminaries such as Jigar Shah, Dan Shugar, and Stephen Lacey, so Josh was honored to be invited to be another guest on Nico’s show.

Josh and Nico didn’t exactly have a beer together, but they talked as if they did. They not only discussed solar and energy storage best design practices, but also about the influences in Josh’s life growing up and his vision for the solar+storage future. They talked so long that Nico had to break up the interview into three parts.

All three Suncast episodes are embedded below. You can also subscribe to Suncast on ItunesStitcher, or your favorite streaming service.

Here’s a rundown of what Josh and Nico discussed:

Episode 81: Tactical Tuesday with Josh Weiner

Episode 88: Battery Net Metering Changes Everything

  • SepiSolar’s foundation story and what separates them from others
  • Lessons learned from Akeena Solar’s IPO and dramatic growth
  • The not-so-strange connection between Music & the Solar Industry?
  • The incredible impact a neighbor can have on a young mind

Episode 89: How a Downed Boeing Dreamliner and a NY 7/11 Store Influenced the Solar Industry

  • How a 7/11 in New York became the pivot point for the storage industry
  • How a downed Boeing Dreamliner changed Josh’s career trajectory
  • A clear case for including energy storage in the solar Investment Tax Credit
  • According to Nico, one of the best answers to his Crystal Ball question in the history of SunCast


Hope you enjoy these episodes and get to know Josh and why he’s so passionate about solar and energy storage. Oh, and if you want to meet Josh in person…

Register for the Intersolar Tweetup

The Intersolar Tweetup is a bi-annual Happy Hour event where the solar Twitter tribe gathers in one place to meet each other in person.  See the faces behind the solar industry’s brands.

Aside from @SepiSolarJosh, you’ll meet Tor “@SolarFred” Valenza, our Director of Marketing who Tweets for @SepiSolar. The event is free to attend, but there’s limited space in a private venue across from Intersolar, so be sure to RSVP!


June 20, 2018 0


SepiSolar’s CEO Josh Weiner was recently interviewed by David Brearley in SolarPro Magazine’s In-House versus Outsourcing Solar Engineering Services in the May/June 2018 issues.

Not every solar company needs to be outsourcing solar engineering and design, but Josh comments on why quality design firms can be the most efficient and cost-effective solar service solutions for many solar contractors, developers, and EPCs.

SepiSolar engineers aren’t just NABCEP solar+storage design experts, they’re also requirements experts, producing designs that meet the detailed requirements of of any AHJ or utility across the U.S.

Read the Interview Here




April 5, 2018 3

As California energy storage becomes more widespread, utilities have been concerned about battery owners charging their systems from the grid at a lower price and then selling that same utility power back to the utility at a higher price and receive net energy metering (NEM) credit.

To address this important policy issue, our CEO Josh Weiner has been working with the California Solar and Storage Association (CALSSA) and our client NEXTracker to suggest a technical firmware solution for inverters that would prevent batteries from charging from the grid, thus allowing DC-coupled PV plus storage systems to participate in utility NEM programs.

We’re proud to say that Josh’s technical firmware solution has been embraced by both CALSSA and the utilities and appears to be on its way to being approved by the California Public Utilities Commission. (CPUC).

You can read the full Greentech Media article, “The Time Has Come for Battery Net Metering” by Julian Spector here.


March 5, 2018 0

SepiSolar’s Josh Weiner was recently interviewed about trends in solar+storage design and engineering by Barry Cinnamon on “The Energy Show,” a radio program on KDOW Radio AM in San Jose California, as well as a popular solar industry podcast.

Josh and Barry have a long solar and storage relationship together going back to when Josh was leading Barry’s engineering department at Akeena Solar, the first national solar installation company. Their lively conversation talks about solar and storage trends, which includes a conversation about some new and improved alternatives to Lithium Ion-based storage systems.

Click below to listen to the show on SoundCloud, or you can also download it as a podcast on Itunes here.

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