September 8, 2023

Why does technology seem to move so fast, yet so slow at the same time? At this point, you’ve probably seen articles hyping up how tomorrow’s technology is being innovated at lighting speeds. If you have, it always seems like new technology is on track to disrupt and transform your life as you know it, yet you feel like you only experience a slight impact in your day-to-day life.

The reason for this is because of the relationship between technology and regulation. Here’s how it usually breaks down:

  • Technology moves quickly; regulation moves slowly
  • Technology innovates; regulation standardizes
  • Technology is private; regulation is public
  • Technology makes things cheaper; regulation makes things more expensive

The bottom line is this – we need to get technology and regulation to cohesively come together, and we need to understand that we’ll be met with errors along the way. Sure, technology evolves to make our lives better, but anything new always comes with risk. Regulation steps in to help new technologies progress, but with concern for public safety taken into consideration.

This push and pull between technology and regulation is simply the price of human progress. Even though sometimes our innovations get ahead of us from a regulatory standpoint, we need to bridge this gap to usher in the sparkling promises of the future.

Technologists and Regulators Need to Learn Together

The first step is to understand that everything is always a learning process. As new technologies make it to market, we learn how they work and what causes them to fail. Even though learning is essential, we start running into problems when these failures cause the loss of life or property. And when this happens, regulators (understandably) get more involved.

Let’s take lithium batteries for example. Although there are several benefits of these batteries, we’ve also learned that they can cause scooters to explode in people’s apartments, reignite automotive fires, and lead to lung damage. But technology isn’t the only risk-generating component; regulators make their own mistakes as well.

For instance, the lack of differentiation between regulatory bodies leads to both over and under-regulation of key risks. To give you an example, failure to distinguish between toxic and non-toxic chemicals in different flow battery chemistries can cause less expensive technologies to become more expensive. Without cohesive regulatory standards in place, we risk driving up cost with no added benefit to public health or safety.

When you consider both sides, it becomes apparent that we need a balance between technological innovation and regulatory standards.

How We’ve Solved Real-World Regulation Challenges

It probably comes as no surprise to learn that we have first-hand experience with this balancing act. In the early 2010s, we were hired to electrify a rental car company’s fleet at a prominent east coast airport. Because SepiSolar was one of the first to permit a grid-connected lithium battery system, we knew that obtaining that permit was going to be tough.

The reason was because we were installing batteries to add to the site’s electrical capacity. With this airport, we had to factor in the 100-year-old copper wires underneath the city. And as you can imagine, ripping them all out wasn’t an option.

By using a solar battery, we were able to charge the airport’s EVs without adding strain on the grid. However, the regulations for the time didn’t mention anything about lithium batteries. At that moment, we knew that regulators and code books had a lot of catching up to do.

Yes, we successfully electrified the car company’s fleet, but a lot of learning took place in the process.

In this case, our system included a main service panel with a 400 Amp (A) service feed from the utility company into a 400 A service and distribution panel. To electrify the fleet, we needed to add an additional 100 A to charge all the EV chargers.

Since we couldn’t increase the 400 A service from the utility company (without setting the city on fire, apparently), we increased the panel from 400 to 600 A and added a new 100 A circuit breaker from a battery to supply the new EVs. Now to charge the battery, we also had to install a 100 A solar photovoltaic (PV) system.

At this point, we had a 600 A service panel, 500 A of load, 100 A of battery and 100 A of PV, which became a lot of power flowing in different directions. If you’ve ever worked with regulators before, it definitely raises an inspector’s eyebrows to see 600 A worth of load and 600 A worth of supply all being controlled by a computer. They start asking the big questions, like what happens if the energy management system gets hacked? And what happens if the PV and battery fail?

To make this work, we teamed up with city regulators to design and build the lithium battery containerized product. We also tailored the entire project to the relevant standards and intentions behind the health and safety codes that existed at this time. The end result was an out-of-the-box approach to code and standards development that ensured all project requirements and stakeholder concerns were properly addressed.

To learn more about we’ve closed gaps between regulations and new battery technology, check out our Net Energy Metering white paper.

How We’re Preparing for Tomorrow’s Regulations

As we mentioned a previous blog we’re seeing the next phase of infrastructure planning start to take shape when it comes to Electric Vertical Take-Off and Landing (eVTOL) vehicles. Heliports might not be new, but landing a flying car on them most definitely is.

Regarding eVTOLs, SepiSolar led the development of the first skyport permit application in the US. Throughout the process, we learned about Federal Aviation Administration rules and regulations, heliport construction processes, and best practices, which increased our appreciation for the role that regulators play. Regulators come armed with knowledge of the prevailing local, state, and federal codes. Not only that, but their technical competency also allows them to address risks and weigh them against the benefits eVTOL consumers will enjoy.

Because of this combined, mutual effort between technology and regulation, we can look forward to the future that eVTOLs will unveil. In a few years, a two-hour commute can turn into a five-minute ride, after permitting and siting considerations are accounted for.

For projects bringing innovation and safety together, SepiSolar has the creative engineers from Silicon Valley (and the licensed professional engineers who govern safety) who know how to get it done.


September 1, 2023

When you think of a regular carport, you probably picture a glorified roof. Nothing special or remarkable, just another roof and a few columns that wouldn’t spark a second thought.

But what if we told you that these seemingly-basic structures can (and should) be used to charge EVs? With a well-thought-out solar mounting system, any business with an outdoor parking lot can use the sun to its full advantage, thereby reducing energy costs associated with EV charging.

As EV adoption continues to skyrocket year over year, having available charging stations is becoming more important than ever. With EV ownership expecting to soar to 35% this year, now is the time to think about boosting your business’s charging capacity.

So, if solar-powered carports are on your mind, here’s what you need to consider before you start building to ensure the success of your project.

Foundation Engineering

For most parking lots, a soil analysis or civil survey was completed at some point to detail the specifications of the parking lot. Depending on how recent that analysis took place, it could be useful data for optimizing the carport’s foundation. With this information, your engineering team can help minimize the quantity and size of the columns needed for the carports. This is important because adding unnecessary columns can drive up the overall materials cost.

At SepiSolar, we coordinate this with our civil and geotechnical subcontractors to make sure the structural and electrical elements are working together right from the beginning. We make sure your solar carport is scaled and engineered properly without any unneeded costs, saving you time and headaches in the process.

Lighting and Photometrics

In California, Title 24 and outdoor lighting requirements make photometric analysis a necessity for carport projects. The last thing you want is to be almost through with building your carport, only to find that it’s not up to code. When this happens, you waste time and money backtracking when you could otherwise be moving forward. The photometric analysis process is critical for understanding how light impacts its surrounding space, and failure to address it can lead to accidents in the parking lot. For this reason, photometric analysis should always be done before erecting the carport structure.

SepiSolar routinely delivers photometric analyses so your carport is fully in compliance. We love designing the generation and the load sides of our projects in tandem, because we excel at making the two seamlessly come together.

Architectural Services

Parking lots are required to comply with the Americans with Disabilities Act (ADA). To meet ADA standards, we often need to relocate parking spaces and develop striping plans that accommodate access. In California specifically, each space needs to be 18 feet long by 9 feet wide, with the access aisle on the passenger side. In addition, long distances to building entrances, unpaved traveling paths, and the omission of ramps can bring your carport out of compliance.

At SepiSolar, we believe that everyone deserves universal access to clean, green, renewable electricity, so be sure not to overlook these key details.

EV Charging

When the solar generation, battery, and EVs are all located in the same vicinity, you can get cost savings you would otherwise miss if you didn’t fully plan through the solar layout, demand charge requirements, and EV charger locations. By making sure all of this is properly accounted for, you can set your carport up for long term success.

In our experience, we regularly see developers and engineering, procurement, and construction teams overlook important aspects of these systems. If you want to sleep well at night knowing no requirement, standard, or consideration was missed, SepiSolar has the expertise to get the job done right.


August 1, 2023

When you picture the distant future, do flying cars come to mind? If so, floating your car above rush hour traffic might be closer than you realize.

This past June, Alef Aeronautics broke major ground for the future of EV transportation. The company made history and solidified itself as the first to get permission from the Federal Aviation Administration (FAA) to test its flying electric car, both on land and in air. This leap forward puts us one step closer to flying cars in real life.

With cars now being tested in the sky, the bottleneck for commercializing these cars, otherwise known as Electric Vertical Take-Off and Landing (eVTOL) vehicles, is no longer the cars themselves – it’s the charging infrastructure. Before we can soar through cities, we need to make sure eVTOLs can stay up and running.

Charging Challenges

In a nutshell, we can think of these eVTOLs as EVs on steroids. EVTOLs have larger batteries than regular EVs, but despite their larger batteries, they need to be charged more quickly and more frequently. For context, a typical eVTOL can only travel between 100 and 150 miles on a single charge. That’s about the same distance as Los Angeles to Palm Springs, or from Fremont to Sacramento. This means that to make these flights affordable, we need to fly them often, and we need to fly them efficiently.

To give you a bit more detail, every eVTOL with a typical 300 kWh battery pack needs a 1.5 MW charger just to recharge in 15 minutes. That’s a lot of demand charges, and yes battery project developers, we’re looking at you. We need you now more than ever.

Even with all of this considered, the amount of power needed to charge an eVTOL opens its own set of issues. Utility companies are already struggling to meet the charging demand of standard EVs, so accommodating eVTOLs will only be more daunting. While some eVTOL companies plan to handle this by calling the utility companies, paying a high rate, and hoping for the best, it’s not a feasible, long-term solution.

What’s Next?

While a practical way around eVTOL battery range and power challenges doesn’t exist quite yet, eVTOLs can become a commercial possibility if we streamline the charging process. Because eVTOLs need such frequent charging, the path forward is to charge them as quickly and painlessly as possible.

Creating an ideal charging experience will require a combination of batteries, utility grids, and renewable sources. In addition, eVTOLs will require microgrid controls that bridge the gap between their charging needs and the utility companies. This will provide an extra layer of resiliency in case the utility grid goes dark.

We know this works, because we’ve been addressing similar infrastructure problems since our founding in 2010.
One key highlight was our work with a major rental car company. The company wanted to electrify its vehicle fleet at a large east coast airport, but the high cost of energy (kWh), demand (kW), and utility grid capacity stood in its way.

Taking this into consideration, we provided a battery system that mitigated demand charges, as well as a PV system that reduced energy charges and recharged the battery system. By doing this, we enabled the rental car company to electrify its fleet in a way that was cost effective and sustainable.

Because of how we approached this situation, the company didn’t need to pay its regional utility company to upgrade its distribution feeders, nor did it have to pay for high energy and demand costs related to its EV charging systems.

We’ve been solving EV charging challenges for the last 13 years, and we’re well positioned to break barriers for eVTOLs in 2023 and beyond.

The Future of eVTOLs

Transportation and energy infrastructure have already been converging to provide back-up power, vehicle-to-grid services and vehicle charging for regular EVs. We see this with home garages that are taking the place of gas stations, but eVTOLs have their own considerations. Not only are they too big for residential, but the FAA will need to regulate them to ensure they have the proper aviation infrastructure and certifications.

SepiSolar has already done the work of researching the FAA requirements and codes to design and engineer heliports and landing pads for the eVTOLs of the future. We solved the problems of EV charging when demand charge managing batteries didn’t exist, and solar integration was at risk due to utility curtailment issues.

With eVTOLs on the horizon, SepiSolar is providing value-added engineering services to help bridge the gaps that currently exist between eVTOLs, renewables, energy storage, and the utility grid. Take advantage of our expertise, and let us support your skyport and vertiport projects.


July 21, 2023

California AB 2143 – the widely talked-about legislation within the California solar industry – will go into effect on January 2024. This controversial bill requires prevailing wages for all construction workers involved in commercial and non-residential solar projects.

Signed in September 2022, this bill comes with apparent consequences for noncompliance. Most notably, it allows California’s major Investor-Owned Utilities to deny Net Energy Metering (NEM) to such systems if prevailing wages aren’t paid. This can result in significant cost increases to these systems, which in turn, reduces the number of systems that would be financially viable. To ensure compliance, contractors will need to submit payroll records twice per year to the California Public Utilities Commission (CPUC).

With just over five months until the bill goes into effect, let’s take some time to solidify your next steps.

As a Contractor, what are my Options?

Option 1 – Just pay the higher wages

While this may be the most obvious solution, we know that higher interest rates are already making it more difficult to get a reasonable rate of return. On top of that, higher wages will reduce the number of available projects. If your company is working on a commercial or large-scale project that won’t be completed before end of year, it could be time to start planning for increased wages if an alternate solution isn’t feasible.

Option 2— Emphasize selling and installing residential systems

This could be a great option for businesses that can pivot easily, but this approach still comes with its drawbacks. First, working with residential homeowners requires more warehousing, a greater commitment to customer service, and a much larger sales team. Second, the rush to residential could become a popular strategic decision, making the market even more saturated.
Although some companies will surely benefit from this approach, this isn’t a blanket solution.

Option 3 – Sell and install systems that aren’t enrolled in Net Energy Metering

With AB 2143 looming in the background, coupled with the recent shift to NEM 3.0, it’s clear that the CPUC wants to halt new solar PV installations. But despite government efforts, renewable energy isn’t going away – it will only continue to grow.

To learn how to maximize solar savings under NEM 3.0, check out our previous blog.

As the new bill goes into effect, the logical next step is to focus on energy storage. With NEM 3.0’s reduced daytime credits and AB 2143’s prevailing wage requirements, systems will benefit from being predominately self-consuming. This means the solar PV will get used immediately or stored in a battery, but it won’t go back on the grid. The battery will also be used to meet the building’s power needs until it runs out, and this cycle will repeat daily.

In a future blog post, we’ll compare different strategies to address energy storage.

Conclusion: Setting Yourself up for Success

Now more than ever, the clearest path to renewable energy is through storage. At SepiSolar, we’ve consistently found that sales strategies focused on solar and storage combined are the most effective for navigating California’s ever-changing solar energy industry.

With 13+ years of experience in designing microgrids, we also understand the unique engineering challenges that are inherent these systems. This is because we excel at combining technologies like solar PV, energy storage, electric vehicles, and hydrogen and fuel-based generators to create complex microgrids that meet customer requirements.

As the future of solar unfolds, we help our customers thrive through the changes.


April 13, 2023

The California Public Utilities Commission (CPUC) recently passed the NEM 3.0 bill, which brings significant changes to the state’s net metering policy compared to the previous NEM 2.0. As a homeowner or business owner interested in solar, it’s essential to understand the differences between the two policies and the new opportunities they present. In this blog post, we will explore the key differences between NEM 2.0 and NEM 3.0, and how to effectively sell solar panel systems to maximize savings under the new policy.

NEM 2.0 vs. NEM 3.0: Key Differences

The Value of Export Rates

Under NEM 2.0, customers received a full retail rate for any excess electricity they exported to the grid, allowing for a faster return on investment (ROI) in solar energy systems. With NEM 3.0, export rates have been reduced by about 75%, meaning customers will receive less money for the energy they sell back to their utility company. As a result, it may take longer for homeowners to recoup their investment in solar energy.

Instantaneous Netting

NEM 2.0 calculated electricity rates every hour based on a user’s net generation and usage during that hour, which was more favorable for solar customers. NEM 3.0 introduces instantaneous netting (or rapid cycling), allowing meters to communicate in real-time instead of hourly. This change may result in less financial benefit for solar customers and more complex calculations.

Grid Participation Charge

NEM 3.0 introduces a “Mandatory Grid Participation Charge” that requires all participants to pay a fee for using the network’s resources and services. Solar customers can expect to pay an extra $8 charge per kilowatt (kW) of solar power capacity, resulting in an average additional cost of $48 per month for homeowners, further reducing solar energy savings.

Strategies for Maximizing Solar Savings under NEM-3.0

Emphasize long-term savings and environmental benefits

Despite the policy changes, solar energy systems still offer significant long-term savings on electricity bills and environmental benefits. Communicate the long-term advantages and the positive environmental impact of solar energy investments, such as reducing greenhouse gas emissions and conserving natural resources.

Promote solar+storage solutions

With NEM-3.0 encouraging battery storage adoption, solar providers can promote solar+storage solutions to maximize self-consumption, take advantage of time-of-use (TOU) rates, and provide backup power during outages. By incorporating battery storage, customers can offset the reduced export rates and increased grid participation charges under NEM 3.0, achieving substantial long-term savings.

Offer tailored solar+storage solutions

With NEM-3.0 encouraging battery storage adoption, solar providers can promote solar+storage solutions to maximize self-consumption, take advantage of time-of-use (TOU) rates, and provide backup power during outages. By incorporating battery storage, customers can offset the reduced export rates and increased grid participation charges under NEM 3.0, achieving substantial long-term savings.

Leverage available incentives and financing options

Despite the higher initial costs of solar+storage systems, customers can still take advantage of various incentives, such as the federal solar Investment Tax Credit (ITC), California’s Self-Generation Incentive Program (SGIP), and other state and local incentives. Additionally, offering flexible financing options like solar loans, leases, and power purchase agreements (PPAs) can make these systems more accessible to a wider range of customers.

Build trust through transparency and education

Establish credibility with your customers by being transparent about the costs, savings, and potential challenges associated with solar+storage installations under NEM-3.0. Provide honest and accurate information, and educate your customers about how solar+storage systems can help them maximize their savings and reduce their environmental impact. By fostering long-lasting relationships built on trust and transparency, you will position yourself as a valuable partner in their clean energy journey.

Conclusion: Learn to thrive in California’s dynamic solar energy market

Although the NEM 3.0 policy brings significant changes to California’s net metering landscape, there are still opportunities for solar providers to help customers maximize their savings. By understanding the key differences between NEM 2.0 and NEM 3.0, promoting solar+storage solutions, offering tailored recommendations, and leveraging available incentives, you can help your customers make informed decisions and achieve long-term savings. By adapting your sales strategies and focusing on the benefits of solar+storage, you can continue to thrive in California’s dynamic solar energy market.


March 8, 2023

In today’s rapidly changing world, companies are always looking for ways to streamline their processes and provide their customers with the best possible experience. SepiSolar is no exception. As a leading provider of renewable energy engineering and planning, the company is constantly seeking new and innovative ways to improve its services and stay ahead of market demand.

That’s why we are excited to announce that we are now able to perform in-person site surveys! Led by Peter Florin, our resident electrical contractor of 45 years, SepiSolar is now able to perform site surveys for projects in California.

In-Person Surveys Reduce Project Costs

In the past, SepiSolar relied on 3rd parties or remote surveying techniques to gather information about potential sites for renewable energy installations. While these methods were fast and cost-efficient in the beginning, they had their limitations and impacts to cost and schedule further down the project timeline. For example, remote surveys often lacked the detail and accuracy needed to provide a comprehensive assessment of a site. This could lead to clarifications that are found late in the design process, which could lead to issues during planning and construction that ultimately lead to change orders, impacting project costs and schedules.

With in-person site surveys, SepiSolar is able to gather much more detailed and accurate information about a potential site. The survey team will visit the site in question, assess the physical and environmental conditions, and gather data on factors such as potential electrical interconnection locations, electrical upgrade needs, conduit paths, and even roof details for structural feasibility analysis. This information will be used to streamline the design process, mitigate negative impacts to cost and schedule, and reduce construction risks.

site survey

SepiSolar is Committed to Strong Industry Relationships

In-person site surveys also provide SepiSolar with the opportunity to interact with the site owners and other stakeholders. This allows the company to answer any questions they may have, address their concerns, and provide a more comprehensive and personalized solution. This level of customer engagement and support is essential for building strong, long-lasting relationships with clients.

The addition of in-person site surveys to SepiSolar’s services is just one of the many ways that the company is driving innovation in the energy industry. With a commitment to providing the best possible experience for its customers, SepiSolar is poised to continue growing and evolving to meet the ever-changing needs of the market.

SepiSolar Leads the Way for Renewable Energy Design and Engineering

SepiSolar’s ability to perform in-person site surveys is a major step forward for the company and a significant development in the energy industry. With more accurate and detailed information about potential sites earlier in the process, SepiSolar can minimize project costs while designing the most effective and efficient renewable energy systems. By putting the customer at the center of its services, SepiSolar is positioning itself for long-term success.


December 23, 2022

Last month we launched a Thanks/Giving program that expressed gratitude to our clients for their loyal business in 2022. With that gratitude we wanted to give back. We searched for an organization that fit not only the mission and goals of SepiSolar, but also the missions and goals of most of our clients so that, in a way, we were donating on their behalf. We searched for an organization that supported the growth of the solar industry, and alleviated burdens of low income and disadvantaged communities.

On Wednesday, November 23rd, we announced that 1% of SepiSolar’s expected 2022 net income would be donated to GRID Alternatives. In this month’s blog post, we’d like to tell you more about Grid Alternatives, and why we feel they’re a good fit for our Thanks/Giving program.

About Grid Alternatives

GRID Alternatives is a non-profit organization that works to promote and provide access to clean, renewable energy for low-income communities. Its mission is to make renewable energy technology and training accessible to underserved communities, and to promote the use of renewable energy as a means of addressing social, economic, and environmental issues.

GRID Alternatives works on a variety of projects in the United States and internationally, including the installation of solar panels on the homes of low-income households, the development of community solar projects, and the implementation of energy efficiency measures in affordable housing. The organization also provides job training and education programs for individuals from underserved communities, helping them to enter the renewable energy industry.

GRID Alternatives’ work has a number of impacts, including reducing greenhouse gas emissions, improving public health by reducing air pollution, and providing affordable access to clean energy for low-income households. The organization’s job training programs also help to create career opportunities in the growing renewable energy industry, particularly for individuals from underserved communities who may have previously had limited access to these types of jobs.

GRID Alternatives Helps Low Income Families

GRID Alternatives has a number of specific impacts on low-income families:

1. Reduced energy bills: By installing solar panels on the homes of low-income households, GRID Alternatives helps to reduce energy bills and make energy more affordable for these families. Solar panels can generate a significant portion of a household’s energy needs, which can result in significant savings on monthly energy bills.

2. Improved health: GRID Alternatives’ work helps to reduce air pollution, which can have a number of health benefits for low-income communities. By promoting the use of clean, renewable energy sources, GRID Alternatives helps to reduce the negative health impacts of air pollution, such as respiratory issues, heart disease, and stroke.

3. Economic benefits: GRID Alternatives’ job training programs can provide economic benefits for low-income families by helping individuals from these communities enter the renewable energy industry and gain access to well-paying, stable jobs.

4. Environmental benefits: GRID Alternatives’ work helps to reduce greenhouse gas emissions and protect the environment. By promoting the use of clean, renewable energy sources, GRID Alternatives helps to reduce the negative environmental impacts of fossil fuel use, such as air pollution and climate change.

Overall, GRID Alternatives’ work helps to improve the quality of life for low-income families by reducing energy costs, improving health, providing economic opportunities, and protecting the environment.

GRID Alternatives Trains the Next Generation of Solar Professionals

GRID Alternatives provides a variety of training programs to help individuals enter the renewable energy industry and become solar professionals. These programs include:

1. Hands-on training: GRID Alternatives provides hands-on training opportunities through its solar installation projects, where individuals can work alongside experienced solar professionals and learn about solar panel installation and other related skills.

2. Formal education programs: GRID Alternatives offers a range of formal education programs, including courses and certification programs, to help individuals learn about renewable energy and gain the knowledge and skills needed to become solar professionals.

3. Apprenticeship programs: GRID Alternatives offers apprenticeship programs that provide on-the-job training and education, allowing individuals to learn from experienced professionals while also earning a wage.

4. Job placement assistance: GRID Alternatives provides job placement assistance to help individuals who have completed its training programs find employment in the renewable energy industry.

Overall, GRID Alternatives’ training programs are designed to provide individuals with the knowledge and skills needed to enter the renewable energy industry and become solar professionals, with a focus on helping individuals from underserved communities gain access to these types of careers.

During this season of giving, we encourage everyone to give generously to an organization they believe will make the world a better place. We chose GRID Alternatives. Whatever your focus or beliefs, let’s all find ways to contribute, to give back, and to uplift those less fortunate than us.

From all of us here at SepiSolar, Happy Holidays and Happy New Year.


September 1, 2022

This summer, the California Public Utilities Commission rolled out a new set of rules for utilities to decide when solar and energy storage projects get permission to interconnect with the grid. We’ll share some information that has helped us understand what’s happened, plus a short Q&A we put together with support from the Interstate Renewable Energy Council (IREC), an advocate for regulations supporting clean energy adoption and a driving force for the new rules.

Interconnection is a mission-critical step in renewable energy project development. To get interconnection approval, projects have to show they can operate safely and reliably and prevent grid disruptions. Projects need an interconnection agreement before they can start exporting energy to the grid.

California, like many states, has had long-standing rules to screen projects for potential to compromise grid reliability so projects can be approved to interconnect faster when the risk of grid disruption is de minimis. But as more renewable energy projects come online, fewer projects are passing this screen.

Out: 15% limits on annual peak load

Under the old rules, projects passed this screen, avoiding additional time-consuming studies by the utility, if distributed energy made up less than 15 percent of the annual peak load on the nearest electric distribution lines. Once distributed generation topped the 15 percent limit, projects could be held up for further review. In a recent PV Magazine article, one project developer said commercial and industrial solar projects often wait more than three years for interconnection approval.

California’s new rules ditch the 15 percent threshold and replace it with a more precise analysis of the grid’s operational limits, known as a hosting capacity analysis (HCA). The analysis, as described on the IREC website, shows where distributed energy projects can seamlessly interconnect to the grid. It also shows where solar and storage can add value to the grid and where network upgrades are needed most.

Want to find out how suitable a project site would be for solar and energy storage projects? Here are maps with results from the latest analyses for California’s three investor-owned utilities.

PG&E and SDG&E require you to register and login before viewing their maps. PG&E provided instant access. SDG&E granted us access after a six-day wait.

The Sepi team would like to smooth the transition for the California contractors we work with, and help inform the manufacturers, contractors and consultants we’re in contact with throughout the industry. See our Q&A with IREC Communication Director Gwen Brown below. Responses have been edited for length. If you have more questions, share them with us on LinkedIn.

What should California contractors do to get prepared for the new interconnection process before it takes effect?

Familiarize yourselves with the hosting capacity analysis of the investor-owned utilities in the territories where you operate.

In: Hosting capacity analysis

How easy is it for contractors to view a hosting capacity analysis to know how a project might be affected by grid constraints in the interconnection process?

Searching an HCA map is like searching any online map, like Google Maps. Just enter the address to view a section of the grid and select the data you want to display. Each map has a legend and user guide for reference.

Here’s a map of the grid closest to the SepiSolar office in Fremont, California, showing the amount of PV generation that can be installed without any thermal, voltage, distribution protection or operational flexibility violations at the time the HCA analysis was performed. Lines with no capacity are colored in red. Lines with more than 2 MW of capacity are green. Purple and light blue show transmission and feeder lines.

Sample of a hosting capacity analysis map

Using tables, you can also view HCA data to find out precisely how much capacity is available for new generation.

Which projects will be eligible for expedited review?

The HCA is the new form of expedited review for all distributed energy resource projects, including solar and energy storage on both sides of the meter. From IREC’s press release: “Under the newly adopted rules, projects that do not exceed 90% of available capacity as shown in the ICA (a conservative buffer requested by utilities) will be able to pass the new screen. Projects that do not pass this improved screen will be subject to supplemental reviews; however, the rule changes also include significant improvements to the supplemental review process that are expected to allow a greater amount of DERs to be integrated through the screening process.”

All projects are now eligible for this review process. If you know a project will fail the HCA screen (that is, it exceeds 90 percent of available capacity), you might want to take another path, such as going directly to supplemental review.

When will contractors notice a difference in the interconnection queue?

Good question. Nobody truly knows the answer yet. It depends how the utilities manage the transition. Review times may vary from one utility to the next. In theory, at least, HCA maps can allow for rapid approval where the grid shows capacity for new projects.

The future of interconnection in California and beyond

Will there be differences in the way projects are treated across California’s three investor-owned utilities, its munis, and other electric service providers?

The process should be the same for each of the investor-owned utilities. Munis and other providers may not have the resources to perform an HCA. The details for each utility can be found in utility advice letters submitted during regulatory proceedings. Here is PG&E’s 342-page advice letter. The advice letter from Southern California Edison can be found here. A search for the file from SDG&E, Advice Letter 3677-E-B, on the utility’s web page hosting electric filings to the CPUC produced no results.

Is there any indication that another state will soon follow in California’s footsteps on streamlined interconnection?

According to IREC’s records on hosting capacity adoption in the US, last updated in February, 16 states are using HCA data in some form or another. The group includes New York, New Jersey, North Carolina, Michigan, Colorado, and Hawaii. A major limitation here is that the HCA has to be of high quality in order to be used for grid interconnection. California was the first to develop HCAs and has the best systems. A handful of other states (see HCA page linked above) have HCAs but most still have further work to do to get them to the point that they are ready for this application.

What other changes can California and other states make going forward to further simplify interconnection?

In the future, the plan per prior proceedings is that hosting capacity data will be used to allow developers to propose seasonal operating profiles for their projects so they could limit export in times when the grid has excess generation (such as spring, before load increases with AC use), and export more during times when that generation is needed on the grid (in summer). That concept was approved in Sept. 2020. Further work is needed to iron out the details. The timeline for that proceeding remains unclear. To learn more about emerging standards for scheduling the import and export of solar, energy storage, and other distributed energy resources, see Chapter 9 of IREC’s BATRIES toolkit for storage and solar-plus-storage interconnection.

Feature image by PG&E, accessed Sept. 1, 2022. PG&E updates ICA values on a monthly basis when significant changes to the feeder occur. Register for an account and login to see the most up-to-date maps in your service territory.


June 8, 2022

Fire safety has always been a hot topic in commercial and industrial solar, now as much as ever.

First responders need to know that crews won’t be put in harm’s way in the event of an emergency. Section 690.12 of the National Electrical Code has led many C&I projects to adopt extra equipment that can reduce system voltage at the flip of a switch.

Contractors have to adhere to safety standards. But they also have to look for opportunities to simplify construction and keep costs under control. Compliance can increase system costs, requiring additional hardware, longer installation times, and time-consuming operations and maintenance.

Manufacturers are starting to bring forward solutions that aim to address safety, simplicity, and cost. Inverter maker SMA America and mounting system supplier Sollega have obtained certification showing that the Sollega FastRack 510 and the SMA Sunny Tripower CORE1 meet the Underwriters Laboratory (UL) 3741 definition of a Photovoltaic (PV) Hazard Control System, as first reported by Solar Builder.

The finding is significant. It means projects can meet rapid shutdown requirements without needing module-level power electronics or mid-circuit interrupters. With permitting approval, contractors can look forward to a whole new category of system design options for rapid shutdown compliance. Sepi provides system design among our project planning services.

But one big question remains: What will the authorities having jurisdiction do?

AHJs are key stakeholders

Developers and asset owners invest a lot of time and money in C&I projects. Investors want to mitigate risk. You increase the risk of project delays any time you stand first in line for approval with a new solution.

The US has more than 20,000 cities and counties. Naturally, we couldn’t ask each one for an opinion on PV Hazard Control Systems. But as a service to the industry, we selected 15 AHJs in communities that install high volumes of solar projects. We included municipalities from the East Coast, the Midwest, the Rocky Mountains, the Pacific Coast, and Hawaii.

We contacted agencies where our communications team had direct contact information for at least one senior official in the department. Many did not respond during the one-week response period we provided.

The variety of responses and the response rate, at 20 percent, underscores some of the industry’s perennial challenges with project permitting. Not only the inconsistency from one jurisdiction to another but sometimes a lack of transparency.

Here are the responses we received.

UL 3741 approval in Sacramento, California

Michael Bernino, Sacramento’s supervising building inspector, consulted with an electrical plan reviewer and concluded that PV Hazard Control Systems would be treated as a design choice which is allowed by code.

“Given the fact that the proposed product is UL listed, it would be approved as code compliant,” Bernino said.

Alternative review process in Tampa, Florida

Florida has not yet adopted the 2020 NEC, which includes the UL 3741 standard for PV Hazard Control Systems. The Florida Building Code incorporates the previous 2017 code.

Until Florida adopts the 2020 NEC, JC Hudgison, Tampa’s construction services center manager and chief building official, suggests an alternative. Try an Alternative Means & Method Request (AMMR) to get projects with PV Hazard Control Systems approved.

The AMMR process gives building officials discretion to approve system designs that satisfy and comply with the intent of existing code. Designs must also provide at least an equivalent measure of fire resistance and safety.

Alternative review in Napa County, California, too

The City of Napa’s Building Division issues permits for commercial solar systems. But a senior building inspector, when asked about UL 3741, directed us to inquire with the county Fire Marshall.

Fire Plans Examiner Adam Mone explained that the Fire Marshall’s review would be limited to a comparison of system designs as presented against the 2019 edition of the California Fire Code. Mone encouraged us to talk with Napa County’s Building Division about compliance with the 2019 edition of the California Electrical Code.

We will update this post if we get Napa County’s perspective on UL 3741 PV Hazard Control Systems. UPDATE: According to Interim Chief Building Official Harvey Higgs, Napa will also accept UL 3741 PV Hazard Control Systems as an alternate means until January 1, 2023, when the 2022 edition of the California Electrical Code takes effect and the devices are explicitly allowed by code.

We will post additional responses from other jurisdictions too.

Ask an AHJ

Want our communications team to ask an AHJ in your community about approval for PV Hazard Control Systems? Send a message through our contact page or email us at

Also keep an eye on our LinkedIn page. We post daily content for renewable energy professionals, including our new monthly feature: Ask an AHJ.


May 2, 2022

Forum, the Consumer Attorneys of California’s bimonthly magazine, discusses how engineering expertise can protect the interests of solar project owners in its latest publication. Sepi CEO Joshua Weiner, a member of the Consumer Attorneys of California (CAOC) expert witness referral network, wrote the article.

CAOC is a 61-year-old professional association based in Sacramento. It provides support and continuing legal education for over 3,000 lawyers. CAOC members represent plaintiffs and consumers on a wide range of claims, including those involving product safety and product defects.

Weiner’s article tells the story of a growing issue for property owners who produce solar energy. After installation, these systems do not always generate the expected financial returns. Consumers then wonder if their contractors can or should be held accountable. The article describes a representative case in Southern California that Sepi handled as an expert.

When expectations go unmet

At an RV park with 434.7 kW of solar generating capacity, Sepi found a system that was producing about 93 percent of its expected energy output but only 58 percent of expected year-one cost savings. Technical performance had hit the mark. Financial performance was amiss.

Utility rate tariffs, it turns out, were both the cause and the solution.

The contractor modeled financial performance based on one of many utility rates offered by Southern California Edison (SCE). The interconnection agreement, a contract that gives permission for solar project owners to interconnect with the utility grid, specified a different rate.

A change in net energy metering, which sets out compensation and fees for solar energy supplied to the grid, led SCE to switch the utility rate once again.

Finally, Sepi analyzed SCE’s utility rates and recommended a different rate that would restore most of the lost savings.

Expertise as a service

Sepi’s engineering team provides expertise for three groups of customers: companies creating solar and energy storage projects, companies creating solar and energy storage products, and various professionals, including attorneys, who need consulting services from an industry expert.

Expert witness services are an important part of our work for attorneys, representing both plaintiffs and defense. We fulfill discovery, analysis, and fact finding for projects that result in financial loss, technical failure, or contractual claims. Areas of expertise include project development, construction agreements, energy technologies, policy, finance, codes, and industry standards.

For free access to the entire March/April edition of Forum magazine, including our article on solar expertise for conflict resolution, visit the CAOC Forum 2022 article index.

To learn more about CAOC’s expert witness referral network, go to the CAOC Vendor Directory. Select ‘Expert Witness Referral’ in the ‘Services Provided’ drop-down menu. Leave all other fields blank, and click on the Search button.

Feature photo by Rachel Brown at Spring Green Graphics

CA Small Business Enterprise

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NAICS Codes:
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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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