June 20, 2018 0

If you missed our first Ask SepiSolar Anything with SepiSolar’s CEO Josh Weiner answering solar+energy storage questions, you can’t ask any more questions, but you can listen to the whole session here:

Josh tackled some great questions from people tuning in to this live and interactive program:

  1. What are some of the common KW inverter sizes for C&I solar+storage? (at 11:12)
  2. When you’re doing solar PV plus storage, what kind of interconnection requirements, like 120 percent rule, do people face? Are you seeing more AC or DC coupling on the system? (at 13:20).
  3. For commercial solar+storage, who are the customers that would benefit the most from solar+storage, and who are the customers that aren’t yet ready? (at 20:40)
  4. What type of energy storage is available and viable for the Florida residential and commercial market? Which brands? Also, does storage benefit from the 30% ITC credit if installed in conjunction with solar? (at 26:00)
  5. For O&M requirements for lithium-ion batteries for C&I solar+storage applications, is there maintenance required on a yearly basis? Or is it bi-yearly? What kind of components need to be serviced? What kind need to be replaced? (at 30:15)
  6. Is there an unbiased accurate chart from an independent testing lab of expected life cycles of all that all the battery brands? (Short answer, yes, but there’s only one that’s public.) (at 38:02)
  7. How does energy solar PV and energy storage work with virtual net metering and aggregate net metering? (at 43:22)
  8. What is the unit based cost for battery O&M? (at 47:10)

Join us for our next Ask SepiSolar Anything

If you have more questions about solar+storage, or energy storage or anything related to solar, join us for our July edition of Ask SepiSolar Anything. You can be in the audience and ask your questions live at Intersolar North America or tune in virtually.

Topic: Ask SepiSolar Anything about energy storage technologies. Josh will be answering questions with our special guest, Matt Harper, Chief Product Officer of Avalon Battery.

When: Thursday, July 12, at 1pm Pacific.

Where: Sign up to get a link to watch via the web or join us live at Intersolar. Get all the info and a reminder here!

P.S. If you’re on Twitter and want to meet other solar people behind the solar brands on Twitter, RSVP for the 8th Annual Intersolar Tweetup, which @SepiSolar is sponsoring. Space is limited.


March 6, 2018 0

The following blog post was contributed by CivicSolar’s Conor Walsh, Senior Account Manager at CivicSolar.



This article is a follow-up to a previous Civic Solar article discussing UL 1741 & Rule 21: Advanced Inverter Tests. We suggest you start with that article first.

Seemingly discontent to be left out of the advanced inverter functionality game, ISO New England (ISO-NE) recently announced new requirements for interconnected PV inverters in Massachusetts. Similar to California’s Rule 21, the new ISO-NE settings requirements are designed to maintain grid stability and resilience during both normal and abnormal operating conditions in the presence of a large volume of interconnected dynamic PV systems.

To achieve this mandate ISO-NE has promulgated a set of inverter ride-through requirements to be manually adjusted on UL 1741 SA  inverters that specify voltage and frequency trip settings and ride-through capability described in the ISO-NE Inverter Source Requirement Document. Implementation of these setting requirements vary by system size:

  • < 100kW: All inverter-based solar PV projects 100kW or less with applications submitted on or after June 1, 2018 are subject to ISO-NE Ride-through Requirements.
  • > 100kW: All inverter-based solar PV projects greater than 100KW with applications submitted on or after March 1, 2018 are subject to ISO-NE Ride-through Requirements.
    • Inverter-based solar PV projects with applications submitted prior to the above dates are encouraged to comply with ISO-NE Ride-through Requirements with the approval of the interconnecting utility.

Don’t fret. ISO-NE is actively engaging inverter manufacturers to ship units with a pre-programmed NE Regional Setting Group, that when selected, defaults to the required setting described in the ISO-NE Inverter Source Requirement Document.

What does this mean for your next PV project in the Commonwealth? First, be sure you are purchasing and installing UL 1741 SA compliant inverters. Below is a short list of compliant manufacturers. Secondly, begin to become comfortable with the ins-and-outs of the new setting requirements and how they are made. It may be several months until a default setting is available.

  • Enphase
  • Fronius
  • SMA
  • SolarEdge
  • Yaskawa – Solectria

For additional readings, please see below:

  1.  What is UL 1741 SA Advanced Inverter Testing and Rule 21?, UL Laboratories, 2016
  2.  2018 Regional Electricty Outlook, ISO New England, 2018

SepiSolar Editor’s note: While UL 1741 SA is a great standard that allows “smart” inverters to work dynamically with the utility grid, SepiSolar is excited about further developments in firmware architecture beyond UL 1741 SA. For instance, with upcoming new solar PV + storage systems, inverter firmware can be modified to allow PV to continue to stay on, beyond the sunset, or in spite of grid instability, without requiring ramping down the real power export of PV. Stay tuned.

If you’d like to contribute your thoughts about solar or storage design, engineering, codes, and standards, please send your articles to  


August 3, 2017 0

August 2 was Earth Overshoot Day, and while it sounds like one of those quirky internet holidays, it is not one that our solar consulting services company celebrates. In fact, it’s a day no one will celebrate. It’s the date when the population’s demand for natural resources in a given year exceeds the planet’s capacity to replenish them. Formerly known as Ecological Debt Day, it marks the point when the yearly deficit truly begins.

The Concept

Earth Overshoot Day is calculated by the Global Footprint Network. This international group strives to changes how the world manages climate change and its ecological resources. They developed the Ecological Footprint, which measures the natural resources remaining on our planet against demand. To determine Earth Overshoot Day, they calculate how many days of the year that the Earth’s biocapacity can fulfill the population’s demand. The remaining number of days left during that year represents the overshoot.

Since Earth Overshoot Day fell on August 2, this means that every day until 2018, we are operating at a deficit of natural resources. This means that all the natural resources used from now until then are unsustainable. It’s a scary prospect considering we are barely halfway through the year.
The first Earth Overshoot Day was devised by Andrew Simms of the New Economics Foundation in London. In 2006, the think tank partnered with Global Footprint Network to launch the first campaign for the overshoot concept. That year, Earth Overshoot Day happened in October. If you do the math, you’ll find that in just over 10 years, we’ve already “lost” two months.

Contributing Factors

Much research shows that the three major factors affecting our dwindling natural resources include deforestation, overfishing and the emission of greenhouse gases. A way you can quickly contribute towards reducing this resource deficit is to go solar! Solar panels use no combustion and therefore emit no greenhouse gases to generate power. Going solar will reduce your carbon footprint and ultimately save you money on utilities.

Click through for information about our solar consulting services.


June 30, 2017 0


You are invited to meet the real people who will be doing your solar drafting work at SepiSolar. We will be awaiting you at Booth # 8520 at the front of the hall at Moscone West 2nd floor at 2017 Intersolar North America, the largest solar gathering in the USA.


Tuesday July 11 – Thursday July 13
Intersolar San Francisco
Josh Weiner’s
SepiSolar Solar Drafting Experts and Consultants


Receive the most personalized service on your solar drafting work with SepiSolar, where your account manager is also your designer.


solar drafting experts



June 29, 2017 0

It’s Energy Week—the perfect time to consider our residential or commercial solar services if you haven’t already. While the Trump Administration’s goal is for our country to become “energy dominant,” you can make a difference just by going solar. While plans to boost fossil fuel production may harm our environment, if we promote energy efficiency and sustainable resources, we can offset some of the harmful effects of greenhouse emissions.

The Plan for Energy Dominance

The Administration recently shared its plans to become self-reliant from other nations. This would make us a secure nation, free from dependency on the countries who use energy as an economic weapon. We would no longer be impacted by geo-political turmoil endured in these regions of the world. Since 1953, the United States has be a major net energy importer; with technological advancements, this can change. The Administration’s goal is to use these innovations to make our great nation a net exporter of natural gas by 2028. This would mean more job growth and expansion across the industry. Yet what will the environment impact be?

How to Make a Difference

What we can focus on now as individuals and business owners is utilizing sustainable energy sources and overall efficiency practices. It’s more important than ever to reduce our collective carbon footprint—and going solar is the perfect way to do this. When you install solar panels, combustion is unnecessary to power your home or building. This means no gas emissions and no environmental repercussions. You’ll also decrease your personal or business’ dependence on energy generated by fossil fuels, which reduces demand on utility companies.

Another way to help the environment and conserve resources is to employ energy efficiency on a personal level. Efficient technologies reduce waste and provide the same level of service using less energy. For example, many have taken to using compact fluorescent bulbs in lieu of traditional incandescent ones, as the former uses less electricity. This kind of practice helps even if you have solar, as it can contribute to your overage. Another great example of energy efficiency is insulation. Insulated homes and buildings require less energy to cool or heat.

If you’re ready to make a considerable difference, contact us now for information about our residential and commercial solar services.


April 20, 2017 0

Saturday, April 22 is Earth Day. It’s the perfect time to consider going solar if you haven’t already. Solar energy was first harnessed

CA Small Business Enterprise

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541330 – Engineering services
541340 – Drafting services
541490 – Other specialized design services
541618 – Other management consulting services
541690 – Other scientific and technical consulting services
541990 – All other professional, scientific, and technical services

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811024, 81101701, 81101516, 81101604, 43232614, 81101505

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