December 14, 2023

California Title 24, also known as the California Energy Code, sets energy efficiency standards for residential and non-residential buildings in the state. Oftentimes, customers hire us to satisfy the solar requirements for Title 24 compliance, but what they might not understand is the importance of bringing their solar subcontractor into the project earlier on.

We’ve said this before, and we’ll say it again. The sooner you bring your subcontractor into a project, the more time and money you can save. By considering this one thing from the beginning, you’ll be in a better position to complete your project on time, on budget, and with fewer complications.

If you want to work smarter and not harder to satisfy the code and get your construction permit, look no further. In this blog, we’ll break down what you need to know about Title 24’s solar requirements, and how you can get the most value from your subcontractor by avoiding common mistakes.

What is Title 24?

Simply put, Title 24 is the energy standard requirement for the state of California. It covers everything from the building materials to use, plumbing, water pressure, insulation, and more. It’s a broad reaching document that touches on anything that has to do with energy usage. This not only applies to buildings, but to parking canopies (AKA carports) as well.

Learn more about how we treat carports.

At Sepi, we manage the solar and the lighting requirements of Title 24. Although not every building needs to have solar to be Title 24 compliant, they do need to be “solar ready.” So, even if a building won’t have a solar system, it needs to be designed in a way that could accommodate one in the future. There are ways to do this cost-efficiently and many more ways to do this cost-inefficiently. Guess which approach we prefer to take?

According to Title 24, “solar ready” is essentially defined as a building that has a panel with a breaker that can accept PV. As you can see, this is a bit vague. Title 24 does address system sizing, energy production, interconnection, labeling, and a few other technical aspects, but it still leaves a lot to be interpreted. Because of this, we’re able to recommend a custom solution that best meets your building’s unique needs.

It’s also important to note that all newly-built California homes will require solar photovoltaic (PV) installations, which of course, is more expensive than simply being solar ready. Despite this requirement, we’ve been able to comply successfully with Title 24 in a few instances without solar PV. In these cases, the homeowner only needed to meet the “solar ready” provision, and this is because we discovered more efficient appliances and lighting fixtures to address Title 24.

Although energy efficient appliances are more expensive, they’re still less costly than a full solar system. When we can achieve Title 24 compliance without solar PV, we’re able to save homeowners as much as $30K from not having to build a new system.

Common Title 24 Mistakes

It’s no surprise that making mistakes can lead to expensive issues down the line. Because of this, a major benefit of working with a solar subcontractor is the ability to mitigate pitfalls before they happen. In our experience, these are some of the most common issues we see – all of which can be prevented by bringing in a solar subcontractor earlier on.

Not installing a line-side main breaker
For homes that require solar-ready compliance, we often recommend adding a line-side main breaker. This way, the homeowner won’t need to shut everything down just to facilitate the solar electrical connection. This approach also allows for more flexibility in terms of system size and configuration. Although this does add a small cost upfront, it’ll save money down the road if the homeowner later decides they want to add a solar system. If you address the code by just throwing in an extra breaker into the main panel, future configuration will become much more expensive and burdensome on the owner.

Failing to save wall space
We also recommend keeping extra wall space available in electrical rooms for future wall-mounted equipment. When architects try to minimize the size of the electrical room, it eliminates any chance for hiding the electrical equipment. If this happens, we’ll end up needing to put it outside where it’s visible. Not only does this defeat the entire point of having an indoor electrical room, but it’s a bit of an eyesore.

Forgetting to install stanchions or stand-offs on the roof
This one is a super common mistake. Sometimes, builders will call us to help identify the locations of the stand-offs so the roofer can seal in the attachments. In this scenario, we’ll usually ask the customer how many they need, and oftentimes, they don’t know. We’ll then ask how big their solar system is, and they often don’t have the answer to that either. That’s when we realize that we’ll need to start from scratch.

When this happens, we need to figure out the homeowner’s future load, extrapolate a PV system size, and then design the roof mounting locations based on that size. Sometimes, we even need to do all of this in as little as three weeks before the roofer arrives. We’ll always make sure to get you exactly what you need, but this is a stressful situation you probably won’t want to deal with. So, to save yourself time, money, and headaches, don’t forget to install your stanchions and stand-offs early on.

Not running empty conduits from the roof to the interior of the house
This one is becoming less and less common, but we included it because we still see this on occasion. When you don’t run empty conduits from the roof to the interior, we have to install an ugly conduit on the outside of the house. It’s not the worst thing in the world, but it’s still something that can be easily mitigated with just a bit more planning.

The moral of the story is that we’d love to be involved in your Title 24 project as early as possible. Let’s get together sooner, avoid suboptimal retrofits, and get you the results you need.


November 30, 2023

Last year, we asked several Authority Having Jurisdictions (AHJs) about Underwriters Laboratory (UL)3741 – a code that defines safety protocols for rapid-shutdown PV arrays. Although the latest version of the standard is from December 8, 2020, several AHJs across the country had yet to adopt the 2020 NEC at the time we shared that blog. Now that we’re nearly three years removed from the introduction of UL3741, we thought it would be a great time to revisit this topic.

As you may already know, the purpose of UL3741 is to protect firefighters from electric shock on rooftops with solar panels. While similar safety standards have been in place for years, what differentiates UL3741 is its evaluation for product safety standards when a firefighter is on a building with PV. Because firefighters can’t necessarily protect the PV equipment when doing their jobs, these modules are subject to break. When this happens, electrical conductors can be damaged, which exposes the firefighter to potentially fatal conditions.

To achieve UL3741 certification, PV systems need to pass tests that simulate what happens when firefighters fall on damaged equipment. This also accounts for their standard personal protective equipment, the tools they use to put out fires, and their fire-proof chemicals.

However, the benefits of UL3741 go beyond firefighter safety. This new standard can also open doors for cost management by as much as $0.22 per watt. In this blog, we’ll walk you through the cost advantages of UL3741 and how you can get this certification. For more information on the UL3741 evaluation process, contact us to learn how we can help.

UL3741 Can Help Manage Costs

The key benefit of UL3741 for contractors is that it allows for new approaches to streamline construction. Before this standard, contractors had to work around rapid shutdown requirements that were both costly and time intensive. For a bit of context, the previous code required all installers to use module-level power electronics that could reduce each module’s voltage to 80 volts or less within 30 seconds. This may not be the biggest deal in the world for smaller residential solar systems, but it often creates a much more expensive issue for large, commercial rooftops.

Now with UL3741, the solar industry finally has more control over the cost of these systems, because the code allows for solutions that use fewer Module-Level Power Electronics (MLPE). Now, we’re able to create beyond the limitations of MLPE and consider alternative approaches for addressing firefighter safety. This is a major step forward, because it gives us more flexibility to comply with standards while also being more efficient and cost conscious. It’s a win for everyone.

Now that it’s no longer necessary to buy individual rapid-shutdown modules for each solar panel, we estimate a cost savings of around $0.22 per watt, not including any incremental labor savings. When all of this is added together, it can really make a significant difference! Not to mention, there are fewer components that have the potential to fail.

How to Get UL3741 Certified

To get certified, we’re finding that you need to consider the following.

  • Racking and inverters should be tested and listed together. Right now, PanelClaw and Sollega are compiling a list for all inverters, including Chint, SMA, Sungrow, Solectria, Fronius, and more.
  • The arrays should be less than 150′ x 150′. In addition, the wire must stay within the control boundary between the arrays and subarrays, or you’ll need to put additional inverters and racking at the control boundary.
  • The goal is to keep the arrays as rectangular as possible to maintain the control boundary. The less “regular” the array is, the more likely that traditional rapid shutdown devices might make more sense.

To have the greatest chance of a successful AHJ inspection, it’s also important for contractors to fully understand the requirements of their specific AHJ. This will start becoming more straightforward as the solar industry moves toward wider implementation of UL3741. In addition, more MLPE manufacturers are creating productions that are UL3741 compliant, and racking manufacturers are selling systems that allow for string voltages of up to 1,000 Volts Direct Current without MLPEs.

The Sepi Standard

At Sepi, we analyze the technical, economic, and regulatory issues to uncover the best approach for your energy infrastructure. This includes revenue analysis, site evaluation, interconnection, and more. To learn how we can help, book a meeting with us today.


November 9, 2023

All too often, we notice developers & contractors think of engineering site surveys as little more than data collection. They go onsite, snap photos, maybe even record a video, and take down relevant data points. After transferring this data to their engineering firm, a slew of follow up questions, action items, and clarifications often ensue, potentially delaying the project, resulting in re-work, and several coordination meetings that bog down everyone’s time. Why does this happen? Keep reading…

Data Errors
We probably don’t need to explain every bad thing that can happen if the information is incorrect, but we’ll give a quick example. For instance, if you provide the wrong service voltage or voltage configuration (delta vs wye!), your project will be designed to that accordingly. And if that happens, your system won’t turn on when it’s finished. If this were to happen, everything would need to be ripped out, redesigned, and reinstalled, and it would cost a pretty penny more than you originally budgeted for. We’ve actually seen this happen.

Sales/Concept Validation

Ever met a sales or development team that put together a concept layout that doesn’t actually work? Yes, we have too. It’s unfortunately the case that there are tons and tons of rules and regulations that govern real estate usage, and it’s unreasonable to expect everyone upstream from the project planning phase to capture 100% of these details that significantly impact final design. And, SepiSolar must know these rules, or else our work products don’t generate permits. Thus, we prefer to impart this knowledge and experience upstream as far as possible to validate and verify these details before proceeding with mission-critical design decisions that can have costly consequences if changed later. For instance, were all fire setbacks taken into account? Ingress & Egress? Underground lines? Civil survey? Equipment clearances? Operations & Maintenance pathways?  Security fences? Shading obstructions from nearby buildings, hills, or vegetation? And so on…

Critical Path Coordination

This is the single, biggest missed opportunity with any engineering site survey – critical path coordination. The job site is a magical place – all the good, hard, honest planning work is done for and around the job site, the future construction will happen here, the owner may be close by, discoveries will be made, and problems to be solved… Basically, what better place is there to meet with the project owner, GC, subcontractors, and other stakeholders to ensure that all major critical paths are mapped out and accounted for? This is how we maximize the value of a site survey – identify critical paths, coordinate them, and put a plan together, all in one place at one time, with all relevant parties represented and involved.

The moral of the story is not to let something missed opportunities fly by you. Take the extra step to get a proper site survey with appropriate parties present, because at the end of the day, a site survey goes deeper than just data acquisition. It’s also discovery, verification, coordination, and planning, and it covers almost every mission-critical area of your project.

Now that you know why you need a detailed site survey, let’s dive into what that process looks like, and how you can get the most value out of it.

Coordinate with Stakeholders

In general, your biggest players will be your electrical Engineer of Record (EOR), your civil EOR, your structural EOR, the construction general contractor and subcontractors, and the project manager.

With these stakeholders in mind, here’s a breakdown of the value each one contributes to the project:

  • Electrical EOR: They’re the project’s authority for all things power. During the pre-construction planning phase, these engineers not only ensure all electrical components will work properly onsite, but they also decide where to place them.
  • Civil EOR: These engineers handle the overall infrastructure, including pipelines, waste management, zoning requirements, and more. They’re also responsible for testing the building materials and soil to confirm the strength of the foundation. As you can imagine, these aren’t things you’ll want to course-correct later, so make sure your civil engineering team is solid.
  • Structural EOR: Structural engineers are a type of civil engineer who help make sure your project is up to code and compliant with standards. They also design and review foundations, walls, roofs, and more to confirm the stability of your project. Most importantly, structural engineers make sure everyone stays safe during the construction process, so it’s unwise to build without one.
  • Project Manager: The project manager is accountable for all activities that are planned and executed on a project. This includes client communication, contract (and subcontract) management, change management, subcontractor coordination, CPM scheduling, budgeting / estimating, procurement, design development, permitting, utility interconnection, construction, commissioning, acceptance testing, as-built’s, and project close-out. Having a good project manager to control and manage scopes, budgets, and schedules is key for project success.
  • General Contractors & Subcontractors: If finding and managing the engineers on this list seems overwhelming, you can hire a team of experts under one roof. That’s what design-build, GC, and EPC firms are for.

The takeaway is that when you partner with a knowledgeable team during the site survey process, you catch and solve problems before they become expensive, draining headaches. Don’t let yourself become the person that needs to correct any million-dollar mistakes.

Consider the Most Important Information

Now that you know who should be involved in your site survey, let’s look at a few fundamental project components you need to keep in mind. Although this is not an exhaustive list, it’s a good place to start for now.

Offtake Agreements
Most lenders require offtake agreements for loan approval, so they’re extremely important to the success of the project. Basically, offtake agreements are proof that a market exists for the byproduct of the work that you’re doing. Most importantly, they allow you to account for profit well into the future. Because this is one of the most pertinent financial documents you’re going to have, it’s smart to make sure your agreement is as sound as possible.

Interconnection Studies
Conducting an interconnection study mitigates issues with information exchange and data transmission, and it accounts for both primary and alternative interconnection points. This also determines any circuit, voltage, or general reliability issues. Like we mentioned in our example, providing the wrong voltage (or really the wrong number for anything, to be honest), can throw your project budget off the rails. The smartest thing to do is make sure your team collects and applies this data, so there are no unhappy surprises later.

The Site Survey Itself
After your team has taken note of the site’s boundaries, utilities, and overarching features, they’ll transfer the layout from the designs to the site itself to verify the accuracy of the measurements. From there, your team will correct any errors to prevent complications during the project.

While these are some of the most pressing things to consider during the pre-construction planning phase, this is just scratching the surface. Successful construction projects include hundreds of moving parts. Fortunately, SepiSolar has a history of tracking every detail.

Decide What to Do Next

Once you understand what the site survey should entail, now you have to decide if you want to have an in-person or a virtual team. Remote surveying can potentially offer some cost savings, but in our experience, it’s a bit deceptive. When you have everyone on-site and in-person, they better understand how to streamline the work and plan around each other’s strengths, which ends up mitigating some of the extra spend. If you optimize the project right from the beginning, you’re not only getting a higher quality outcome, but you’re also saving time on the backend.

By going through the site survey process in-person, you’re able to have your questions answered in real time. In addition, you can review the design, build execution strategies to optimize the timeline and cost, and solidify an action plan that makes sense.

Sepi has the experience and partner network to ensure your site survey is through, well-rounded, and done right the first time. Contact us to learn how we can help get your project off to a great start.


October 25, 2023

If you’ve ever managed a construction project, you may have found it easier to handle fewer professional engineering firms with several areas of expertise, as opposed to multiple that each have niche specialties. When you select firms that offer a wider range of services, you tend to get better coordination, stronger quality management, and a clearer path to making sure your project is completed on time and on budget. So, instead of hiring a separate Electrical Engineering (EE) firm for your building and another for the solar and microgrid system, here’s why we recommend the “one and done” approach instead.

Consolidating the Process

As the GM or architect, consolidating EE efforts allows for a more fluid experience. You have one firm that knows all things electrical, and ideally, they’ll know how to do things right the first time. When the firm is well-versed in all areas of the EE process, you likely won’t be dealing with expensive issues that could’ve been avoided.

EE consolidation is especially important if you’re working on a multi-family home project, because these projects usually involve multiple meters, including a master meter, tenant meters, and meters for common areas. Because of the complexity of the metering, designing the solar or microgrids can raise some difficult questions. For example, should you sit the meters together in a central location, or do you distribute them across all units? And, does this decision change when incorporating batteries, resiliency, and/or microgrid controls? This type of decision on the “demand side” of the site are best made with the “supply side” (i.e., solar and micro grids) in mind, because there’s a direct relationship between the cost- (and revenue-) efficiency of the solar system and the placement and location of the meters.

Other examples like school campuses, curved roofs, hangars (lightweight metal roofs), and load control systems also benefit from having a consolidated EE firm.

Improving Efficiency and Quality

When you choose the “one and done” approach, you’re able to optimize the complete electrical system – supply AND demand. This also tends to be a more cost-effective approach, since sometimes it pays to adjust the grid system to fit the load, and other times, it pays to adjust the load to fit the grid system.

When we’re engaged in this process, we employ both options to bring you the best system possible. To us, “best” is defined as finding the ideal balance between the highest efficiency, lowest cost, and fastest development timeline.

Bringing us in as the sole EE of record also allows us to speed up your project by coordinating all relevant disciplines to the best critical path management schedule. If there’s a critical path that’s not under our control, the project can be delayed when certain predecessor activities are not completed within the proper sequence. To put that another way, if you have multiple firms working in silos, you may end up lighting dollars on fire trying to backtrack. This is especially true when engineering firms need to be brought in after several major design and electrical decisions have already been made.

The takeaway is to not put yourself in the position of solving impossible electrical issues. You’ll have a much more efficient project if you make sure everything is correctly addressed from the beginning.

What Not to Do

We don’t want to be the one to scare you, but not consolidating your electrical engineering efforts can lead to problems ranging from minor cosmetic issues, all the way to major safety concerns. Fortunately, these problems can be avoided, but let’s look at what can happen when they’re not.

  • Aesthetic Shortcomings: We once worked on a project that involved using solar panels as a façade to hide unattractive mechanical equipment. The issue was, the design of the façade kept changing, and those changes weren’t necessarily the most optimal. Because of this, we had to install “dummy” solar modules that weren’t connected to anything just to make the façade look a bit nicer. If we were involved from the beginning, we could have used smaller solar panels and adjusted the length of the façade to make sure we electrically connected all the solar panels the customer had to buy. This isn’t the worst thing in the world, but it’s an inconvenience and lost generation opportunity that could have been dodged with better planning.
  • Spacing Issues: If we’re not consulted nor hired to work on the building’s electrical distribution system, we often won’t find space in the electrical room for any new solar / microgrid wall-mounted equipment. As a result, we’d need to put equipment in other less-efficient, less-aesthetic, and sometimes, less-ideal conditions to appease the code, project budget, and timeline. It would’ve been far better to design the electrical room with flexibility in mind, or at the very least, with all components considered beforehand. Another example of this is with buildings that have vents and equipment throughout the roof. When we’re the EE of record, we make sure we leave enough real estate available for solar panels before the roof becomes too crowded.
  • Safety Modifications: Sometimes, the EE for a building will spec equipment for the main service panel or switchgear and coordinate that with the local utility company. If this is done without consideration of the solar and microgrid connections, we end up needing to modify the expensive new switchgear to accommodate those connections. This basically entails “breaking” and “fixing” the brand-new piece of electrical gear, then sometimes getting it re-certified and re-listed for safety and compliance purposes. If we were involved from the beginning, we would’ve designed the electrical system for the entire building and ordered the proper gear from the start, with no downstream modifications nor re-designs required.

Making Better Load Decisions

The EEs for the building usually decide how to run load calculations, and often, we notice they could be executed better. For instance, we’ve seen EEs who add heating and air conditioning loads together to determine the building’s full electrical requirements. The issue here is that most people don’t run their heating and air conditioning coincidentally, so they don’t need to be added together. Instead, the EE can take the larger of the two values and use that for load calculation, or at a minimum, discount the sum of the two loads with industry standard discretion.

You might be thinking – okay sure, this could’ve been caught with a bit more scrutiny, but what’s the big deal? The reason is because if load calculations are over-stated, it can impact the microgrid sizing, leading to a miscalculated cost-benefits analysis of the owner or architect’s offset goals. Typically, we like to take into account appliance efficiencies and utilization rates of various loads in order to recommend the most cost-advantageous microgrid design that brings the building’s net demand under the line. This analysis is a bit more involved than simply what a “demand side” EE (for the building) or “supply side” EE (for the microgrid) would do independently of one another, since it’s a multivariate optimization problem when the two are combined into one.

If you’re looking for an EE firm that gets the details right, contact us to learn how we can help bring your project to life.


October 4, 2023

There’s no real way to sugarcoat this, so we’ll just come out and say it. Development is a risky process. It involves a great deal of discovery, analysis, and risk-adjusted decision making. As a result, if you don’t consider the right details at the right time, it could lead to serious cost and time overages, or lingering and long-term liabilities.

Because development is the first phase in the project lifecycle, doing a thorough job is essential for mitigating the “snowball effect.” Without the foundation of strong development engineering, you could be faced with expensive and stressful problems down the line. This can potentially put your project’s planning, execution, and asset operations phases at undue risk.

We don’t want you to experience the pain of poor planning, gaps in due diligence, or the stress of missing pertinent details, so we put this blog together to familiarize you with how SepiSolar approaches the development engineering process. If you agree with what you read here and you’re starting a new project, be sure to contact us for a consultation.

Development Engineering vs Development Project?

Here’s how we see it. All projects require three things: a seller, a buyer, and a transaction. With renewable energy projects, we typically call these three things a site, an offtaker, and a Power Purchase Agreement (PPA) respectively. Each of these follow different timelines and cost streams that require their own due diligence and set of controls. Development engineering is the work involved for discovering, analyzing, and supporting decision-making around these due diligences and controls to create a new project.

How Does Sepi’s Development Engineering Process Work, and What Work Products are Included?

Work Product #1: Fatal Flaw Analysis
(Hint: think of this like a 0% analysis)

Initially, our goal is to kill the project. Why? Because more development projects fail than succeed.

Believe it or not, there are many ways for a project to fail, but only a small handful of ways for it to succeed. Therefore, if a project is going to fail, our goal is to identify the failure as quicky as possible. This is what we call the fatal flaw analysis. It’s when we try to find out if we should move forward, or if we should just “lose fast.” If the project fails the fatal flaw analysis, it allows us to stop spending money on due diligence and redirect those funds toward more fruitful projects.

We promise – nothing is more painful than discovering a fatal flaw too late in the process. When this happens, all the work completed up to that point is essentially wasted. Differentiating between failure and success may not be immediately obvious, but it’s critical for reaching the final work product.

To help us reach our conclusion, we ask questions like:


  • What is required for site control and/or exclusivity?
  • Is it buildable?
  • Is it accessible?
  • What are the land use restrictions or easements?
  • What are the applicable Authority Having Jurisdiction (AHJ) regulatory requirements?
  • What are the utility’s requirements, costs, and timelines?
  • What are the project economics?


  • What is their credit worthiness?
  • What is the project pricing, and is it competitive?


  • What are the liabilities, warranties, and guarantees?
  • How bankable is it?
  • What is the scope, schedule, and value?
  • How is ownership and title treated?
  • What risks and obligations are each party accountable for?
  • What incentives (federal, state, and local) or other benefits apply, and how are those treated?

If you’re wondering what constitutes a bad project, it usually involves an unchangeable condition that prevents the project from being as successful as we’d like it to be. The fatal flaw analysis goes hand in hand with the feasibility analysis as far as the things we’ll need to consider, but like we mentioned, a fatal flaw will indicate that you shouldn’t proceed.

Some common fatal flaws include permitting issues, geological concerns, unfavorable market conditions, unreasonable costs, among others. At the end of the day, we’ll make sure that proceeding with the project is a sound idea.

Work Product #2: Critical Path Analysis
(Hint: think of this like a 30% analysis)

Congratulations! More than 35% of the projects we look at fail by the time they reach this point. If your project has made it this far, it means it’ll take a higher degree of scrutiny to uncover any potential failures.

Now, we’re asking ourselves if there any hidden “gotchas” that could present more risk or cost than the project owner can tolerate. To answer this question, we’ll need to get deep into the project details to understand any latent failures that may exist. This is what we call a critical path analysis.

Naturally, we don’t want to spend all the development funds on every detail of the potential project. So instead, we only focus on the key barriers that might prevent the project from achieving its critical paths. If those paths check out, then the project is worth investing more resources into.

It’s also important to note the importance of the feasibility analysis during this phase, which should consider the following:

  • AHJ: An AHJ is part of the city government, and it’s responsible for enforcing regulatory standards and approving the materials and installation required for your project. We’ll set up a meeting with regulators to make sure what we’re designing and building can be cleared. If clearance doesn’t happen, we’ll need to understand what obstacles must be overcome.
  • Interconnect Requirements: We’ll also want to ensure the project can be connected to the local utility grid infrastructure. To check on this, we’ll submit pre-applications to the electric company and investigate the interconnection capacity.
  • Cost Analysis: This part is obvious, but it’s important to get a sense of the costs for all areas of construction. This will generally include materials, equipment, and labor costs.
  • Revenue Analysis: There are two main types of revenue analysis to be aware of – FTM and BTM. FTM, or Front-of-the-Meter, is largely a discovery process. FTM revenue often involves complex analyses and varying levels of volatility, depending on the market participation. BTM, or Behind-the-Meter, revenue is more straight forward. BTM revenue involves calculating the avoided costs of paying the utility company for power.
  • Incentives: There are incentives all over the place, including depreciation, tax abatements, electrification incentives, agricultural, health, education, and so many more. For that reason, it helps to have a broad understanding of these incentives, both at the federal and local level. Usually, local incentives are administered by a utility company, the state, a township, or a community program.
  • Economic Analysis: This is the point where we’ll take everything we learned about cost, revenue, and incentives and combine them into an indicative pro forma — or a projection of future revenue and expenses. This will gauge the expected Return on Investment (ROI), Net Present Value (NPV), and Internal Rate of Return (IRR).
  • Concept Analysis: This provides a basis for discussion on all the above topics, and it helps visualize the project for all stakeholders.

Work Product #3: Cost Engineering & Constructability
(Hint: think of this like a 60% analysis)

At this point, we’ve determined that this project is more likely to succeed than to fail. We’ve evaluated the critical paths, we’ve identified the risks and benefits, and we’ve agreed that it’s worth quantifying the remaining risks. This part of the process is what gives us clarity on where the project stands commercially, economically, and technically before any binding agreements are put into place.

Now, instead of trying to “fail” the project, we’re rooting for its success. We’re solving problems, reducing and estimating costs, verifying means and methods with licensed contractors and experts, and putting risk mitigation plans into place.

The end result of this work is a full concept design with civil, electrical, interconnection, environmental, and architectural considerations. All of this can be shared with stakeholders to gain their approvals, put executed agreements into place, and start the initiation and planning phases of the final project.

Work Product #4: Contract Negotiations & Applications
(Hint: think of this like a 90% analysis)

Now, we’ve officially settled on a final project cost, revenue, NPV, IRR, and ROI. We understand the regulatory landscape, time, and cost involved. The landowner, offtaker, and any third-party financiers are all on-board.

This is when we’ll call the attorneys and begin executing agreements. During this stage, SepiSolar is largely focused on submitting and processing the two most significant critical paths in any project – the AHJ and the utility company.

We’ll submit the interconnection application and permit application, and we’ll negotiate with the various parties involved, including utility engineers and project managers, zoning and planning departments, building and safety, fire, and more. This allows us to maintain costs, revenues, schedule, and scope. We’ll also support any contract review and negotiation processes with all involved parties, including suppliers.

Work Product #5: Approvals
(Hint: think of this like a 100% analysis)

This is largely an administrative stage that closes out the development stage of the project. After negotiating and working through the contracts and applications, we’ll package all project data, analysis, executed agreements, and final documents and turn them over to the project executive, board, and/or project manager for the planning and execution phases of the project.

This also includes executing on the agreements and purchase orders, as well as maintaining regular communication with key team members. In addition, people will be assigned to support roles for future planning and operations, and for ongoing performance engineering, contract disputes, and warranty claims.

Luckily, SepiSolar has a tried-and-true process for managing the development process. We’ll help you understand and assess risk, and we’ll consult with you on how to approach your project in a way that’s cost and time effective. Contact us to discover how we can help kill the bad projects and support the successful ones.


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.

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