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May 30, 2018 0

 

If you’re an architect, new homebuilder or housing developer in California, you’ve probably heard by now that the California Energy Commission (CEC) has updated its Title 24 solar and energy efficiency standards. Effective January 1, 2020, the update specifically mandates that all new California homes under three stories install solar panels on the roof or achieve an equivalent total home energy efficiency reduction through other measures.

To comply with Title 24, new homebuilders, architects and developers will be required to use Title 24’ssoftware for calculating the building’s “Energy Design Rating” (EDR), which not only includes inputs for solar but also for energy storage and other options.

To give builders more flexibility, the EDR is scored like a golf tournament—the lower the score, the better (or, the more “energy efficient” the home is). The goal is to achieve an equal-to-or-less-than EDR for a solar home than a comparable “regular” home, of the same square footage.

Depending on the square footage and climate, new-home solar will range between 2.7 and 5.7 kW DC to meet the requirements, but that doesn’t tell the whole story. Rather than meeting the minimum requirements, builders may be better off designing their Title 24 solar systems with battery storage.

 

Why Builders Should Include Storage with Solar

As mentioned, the EDR software gives homebuilders a score, but there are many ways to meet that score, and one is combining solar with energy storage. Including energy storage will not only meet the minimum solar requirements, but will maximize energy savings for the home, offering customers a financial advantage over other homes.

When solar engineers design a solar system, they typically take into consideration the following factors:

  • The climate
  • The average amount of sunlight for the area
  • The orientation of the roof in relation to the sun
  • The amount of potential shading over the course of the year
  • The pitch of the roof
  • The home’s annual kWh usage

While these parameters are important, equally important are the utility rate considerations that system designers like SepiSolar factor into their plan sets. These rate policies affect the solar system’s ROI and include:

  •  Tiered Rates. Tiered rates vary by utility and charge customers higher rates when they use more energy over a certain monthly amount.
  • Net Energy Metering (NEM). NEM is like rollover minutes for solar. Utilities will credit solar homeowners for any excess solar power that is exported to the grid. The value of NEM varies by the utility and the time of day that the solar is exported to the grid.
  • Time of Use (TOU). TOU rates also vary by utility. Customers incur charges when they use grid energy. During peak times, such as rush hour when the sun is setting and people are coming home, utilities charge solar and nonsolar homeowners a higher rate when they draw power from the grid, making any exported solar energy less valuable during that time of day.

That’s where energy storage (batteries) comes in.

 

Designing Systems for Overall Cost Savings for Solar and Title 24

Due to the above utility rate considerations, home developers that want to design premium homes that maximize utility savings as well as comply with the Title 24 solar mandate should consider including energy storage systems with their solar designs.

Solar+storage with smart battery management software will counteract the cost of tiered rates and TOU through “load shifting,” and “peak shaving.”

With peak shaving, homes using solar+storage will be able to use as much free solar as they can during the highest TOU rates while saving the excess energy in their batteries instead of exporting to the grid. Then, during peak TOU periods, the home will use this free stored solar-generated energy when the utility rates are high.

Additionally, battery management systems can also “load shift” the time when appliances are turned on or off, such as turning on a dishwasher, dryer or charging an EV when utility rates are low or when electricity can be drawn from the battery that was charged by solar.

Both peak shaving and load shifting with solar+storage encourage the home to use more of its own self-generated power, relying less on importing power from the grid. With so many homes using solar after 2020, homeowners with solar+storage will also help stabilize the grid, and can be paid a higher credit for any power the utility draws from the storage system during peak hours.

Another sales advantage for developers is that solar+storage offers some emergency power in case of a blackout. That is not the case with stand-alone solar PV systems. To protect power line repair workers, stand-alone solar systems will automatically shut down during an outage.

 

Things to Keep in Mind About Solar+Storage with Title 24

If you decide to meet your Title 24 solar mandate with energy storage, there are several requirements to keep in mind.

First, when adding storage to solar, there is a minimum required battery size of 5 kWh. This is a reasonable size that will allow for taking advantage of tiered rates and TOU, and it will provide a minimal amount of backup power in case of an outage.

Second, your solar+storage system designer and engineer will have to select one of three control options for the battery:

  • Option 1 – Basic Control (Title 24, Section JA12.2.3.1): With Basic Control, the battery system can only be charged by the solar system and can only discharge when there’s not enough solar power to meet the home’s current energy usage.
  • Option 2 – TOU Control (Title 24, Section JA12.2.3.2): With TOU Control, battery system will be set up with Basic Control, but will only discharge during the peak TOU hours of the day. This will change from season to season, and must be configured from the battery manufacturer or programmed by the installer at the time of commissioning.
  • Option 3 – Advanced Demand Response Control (Title 24, Section JA12.2.3.3): With this configuration, solar+storage systems will be programmed with Option One or Two. In addition, the battery control system must meet the demand-response requirement of a utility or third-party owner; that is, the utility or third party will be able to remotely control when the battery is charged and discharged. Typically, the homeowner will receive a financial benefit for this utility interaction with the grid.

The rules within each category will most likely be refined over time, so it’s important for your solar designer to be up to date with these standards and make any necessary changes. The above is a summary, so please review the entire Joint Appendix 12 to take full advantage of the above credits.

As longtime solar+storage engineers with thousands of projects, SepiSolar has a great deal of experience designing solar and battery systems that meet the new Title 24 regulations, as well as designing systems that comply with the local requirements of counties and other local authorities having jurisdiction (AHJs). Please contact us if you have any questions about these new Title 24 solar requirements for your new residential solar development projects.

Josh Weiner is President and CEO of SepiSolar, a solar+storage design & engineering firm based in Fremont, CA.

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May 4, 2018 1

Have you seen SepiSolar’s new logo? It used to look like this:


And now it looks like this:

 

When any company goes through a redesign of their brand, customers and frequent visitors can notice and often have an initial reaction (they love it, they hate it, meh.) as well as questions, like “What was wrong with your old logo?” and “What does your new logo mean?” and “What does the number 42 and meaning of life have to do with solar design and engineering?

These are all great questions, so let’s tackle them one by one:

What was wrong with your old logo?

Sometimes our solar engineers can be checking a permit plan set and spot something on the plans that doesn’t match or make sense. That’s how we felt about our old logo. The solar panel array made us look like a solar developer or EPC, and while solar contractors are certainly our customers, a solar array is not a reflection of design or engineering or who we are beyond being in the solar business.

Second, when you look at a brand, it’s supposed to reflect a feeling. Think about Nike and that swoosh of energy. We want the solar industry to recognize SepiSolar in that same way, to see our logo and have a positive feeling, and our old logo never did that. It was “just a logo.”

What does your new SepiSolar logo mean?

Designing and engineering a logo is serious business, and we did consult with a professional who asked us a lot of questions about who we are and what does our SepiSolar name mean?. The short answer is that “Sepi” means “the moment just before the first light of dawn.” So, light and energy emerge and grow from Sepi, and in the same way, solar projects and the power that is later generated emerges out of the plan sets that SepiSolar’s engineers create. Power also emerges out of the engineering solutions we solve as solar consultants.

Our logo designer created several options to have our new logo reflect who we are as a company, but this was the one that immediately resonated with us. Here’s why: 

 

“42 and The Meaning of Life”

As to why we put 42 in the title of this post, if you didn’t catch it immediately, the number 42 is an important but ridiculous part of Douglas Adams’ book “Hitchhiker’s Guide to the Galaxy.”

It’s relevant to our SepiSolar brand because we sometimes feel like we’re part of that ridiculous universe when we deal with the bureaucracy of solar and battery permitting requirements, but it’s not part of our logo. We just thought it would be fun to slip 42 into a blog post title, and fun is part of our community of solar “enginerds,” so 42 is relevant…sort of.

Thanks for reading, and if you’ve missed our latest SepiSolar news and useful info like our SepiSolar Battery Translator Tool, please sign up for our newsletter or check out other news and blog posts! Naturally, please contact us if you’d like a free quote for our engineering services.

Josh Weiner is President and CEO of SepiSolar

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April 25, 2018 0

Attention solar installers! If you haven’t heard the news yet, Schneider Electric recently issued a recall notice on their Square D brand 30A and 60A disconnects due to a defect in the switch mechanism resulting in the connection remaining closed when the handle is in the OFF position.

SepiSolar will be notifying our customers whose designs use these disconnects and offering recommendations on alternative equipment and/or suggesting ways to design around this issue. In the meantime, for your safety and the safety of your customers, we recommend checking any recently-performed installations where these disconnects were used.

You can contact Schneider Electric for information on how to service/replace defective disconnects. Here’s a link to the official CPSC recall notice.

Stay safe!

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April 17, 2018 0

The following guest blog post was contributed by Jim Jenal, Founder & CEO of Run on Sun, a Pasadena solar installer and integrator who often blogs about the Los Angeles area solar permitting, codes and standards. –SepiSolar

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Sweet Relief – LA County Signs-off on Solar for Center-Fed Service Panels

Due to a misreading of the electrical code, many jurisdictions in the Run on Sun service area – and yeah, we are talking about you, LA County – balked at allowing homeowners to install solar if they were connecting to a center-fed panel.  This has resulted in costly, and unnecessary service panel upgrades, and even prevented some homeowners from adding solar at all!

Well, good news – LA County has finally gotten with the program and agreed to interpret the code consistent with the intent of the code’s authors.  Here’s the scoop….

We have written about this problem at some length before – you can see those articles about solar and center-fed panels here.  The confusion arose because the code calls for connecting the solar breaker to the opposite side of the bus from the main breaker.  Since on a center-fed panel the main breaker is in the middle of the bus, there was no “opposite side” to mount the solar breaker, according to that tortured interpretation.  (In the photo on the right, you can see the large, main breaker in the center, with load breakers above and below it.)

To get around this problem in jurisdictions that held to that view of the code’s intent, various approaches were brought forward, all of them more dangerous and/or complicated than simply putting a solar breaker at one end of the bus.  For example, a couple of years ago, San Diego Gas & Electric introduced an adapter ring to fit between the meter socket and the service meter. Soon thereafter, SCE adopted a similar solution, and that became our “go-to approach” for center-fed panels in LA County.

While County would sign-off on the SCE ring (or Generation Meter Adapter, as SCE called it), it was really an awful solution to the problem  For one thing, SCE charged the homeowner just under $500 for the install, and their technician had to do the work in full arc-flash protection gear – a testament to the hazard involved.  Beyond that temporary risk, the connection now left a pair of terminals in the solar disconnect with no over-current protection between them and the power pole transformer.  Short that connection out, and nothing would stop that current from flowing until the wires melted!

A better solution was recently brought to market in the form of the B3-Bypass breaker which we wrote about last Fall.  The B3 fits into center-fed panels and provides a much safer way to interconnect solar than the GMA ring.  But guess what?  Despite it having passed UL certification, LA County will not accept it, as we learned when we attempted to submit plans calling for the installation of the B3!

So, back to square one?  Well not quite.  While on the phone with County’s plan checker, I remembered that a code amendment had been passed in January 2017, which clarified the intent of the code when it comes to center-fed panels. We had cited this amendment to L.A. County last year, only to be told that County had not yet approved the amendment – hence we installed multiple GMA rings with center-fed panels last year.

Here’s the language of the amendment:

A connection at either end, but not both ends, of a center-fed panelboard in dwellings shall be permitted where the sum of 125 percent of the power source(s) output circuit current and the rating of the overcurrent device protecting the busbar does not exceed 120 percent of the current rating of the busbar.

This is what we had been saying all along, and the code amendment makes it clear that this is an acceptable thing to do – as well as being cheaper and safer than any of the alternatives.

So, I asked the plan checker, had County gotten any closer to adopting this amendment?  “Oh,” said the plan checker, “we’ve been accepting it since January 2017!”

Sigh. So not true. At least none of the plan checkers that we encountered in 2017 were accepting the amendment.  And for that matter, this plan checker did not volunteer the information.  Instead, he was about to sign-off on the GMA ring without ever bothering to mention that there was a safer and cheaper way for us to meet the needs of our client!  Is it too much to ask that a plan checker point out policy changes of which s/he is aware when discussing plans with a contractor?

Here’s the bottom line:  If your solar project meets the interconnection requirements set forth in the quoted language above, you do not need to upgrade your panel, and you don’t need a GMA ring to attach solar to your center-fed panel in LA County territory.  (And if it satisfies LA County, presumably every other jurisdiction should go along as well.)

If you need documentation – either as a homeowner to provide to your solar contractor who is trying to sell you an unwanted service panel upgrade – or as a solar contractor trying to convince a recalcitrant AHJ – here’s the link to the California Building Standards Bulletin that approves the amendment, and here is Bill Brooks’ write-up explaining the need and justification for the amendment.

Here’s the money quote from the latter:

The fact that several thousand center-fed panels in good repair have required replacement over the past two years when, in fact these upgrades are unnecessary, presents a real and unnecessary hazard to the field workers required to perform these replacements. Any time a service equipment replacement is performed on a dwelling, utility service must be interrupted and significant electrical work must be performed to replace the equipment. This exposes the electrical worker to hazards of potentially live conductors and inadvertent errors that could even be fatal. The hazards of these upgrades is appropriate when the existing service equipment is damaged or has outlived its useful safe operating life. Performing these upgrades on perfectly good equipment that is not a safety hazard to the dwelling is an unnecessary risk.

We couldn’t agree more!

Jim Jenal is the Founder & CEO of Run on Sun, a Pasadena solar installer and integrator. Follow Jim and Run on Sun on Twitter at @RunOnSun.  

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April 10, 2018 2

“What does the SepiSolar name mean?”

“Josh, how did SepiSolar get started?”

“What makes SepiSolar different from other solar design and engineering services?”

Since founding SepiSolar nearly 10 years ago, those have been the most frequent questions I’ve been asked when people hear about SepiSolar. If you’re learning about us for the first time, or you’ve been a customer and wondered about those same topics, here’s the story:

“What Does the SepiSolar name mean?”

The short answer is that while searching for a name, I discovered that “Sepideh” is a Persian name that is often shortened to “Sepi.” Roughly translated, Sepi means “the moment just before the first light of dawn.” In other words, every morning, anywhere in the world, light and energy emerge and grow from Sepi.

In the same way, solar projects begin with solar design, and all of the clean power that is later generated emerges out of the plan sets that our designers and engineers create.

The Sepi “emerging light and power” concept also suggests infinite clean power generation. Even through the darkest solar coaster times, the sun always rises, and more plans for solar and storage are continually being generated for our customers. Moreover, our engineers are continually thinking about how to improve solar and storage technology, policies, business processes and grid models. The clean energy innovation never stops.

“How did SepiSolar get started?”

I founded SepiSolar in 2008, but my solar career started in 2004 with Andalay Solar (fka Akeena Solar). As one of the first national solar installation companies in the U.S., I learned a lot about the internal operations of a large engineering department, and realized there was a huge need for third-party independent design and engineering services to help growing solar companies during certain seasons, as well as for solar product development.

My vision was that SepiSolar would not only provide extra help to solar contractors with a high volume of designs and plan sets, but that we could also fill in the gaps for structural or PV electrical engineering needs that may be outside of the company’s core competencies, such as architecture firms or commercial building contractors.

I also wanted SepiSolar to be extremely flexible so that we could deliver a full menu of on-demand, seasonal or ongoing solar design and engineering services, such as installation feasibility evaluations, sales-focused drawings for proposals, P.E. stamps, product evaluations, or even develop salesforce modules for tracking inventory and the paperwork for projects.

With that flexible full-service mindset, SepiSolar has grown to become a leading national design and engineering company with a team of NABCEP certified designers and engineers working out of our Fremont, California offices, not overseas.

“What makes SepiSolar different from other engineering or design firms?”

I think of SepiSolar as a community of passionate “solar enginerds.” Everyone here looks at design and engineering through the lens of the entire solar and storage value chain. We don’t just draft line diagrams and crank out plan sets. For some design firms, that’s where the service starts and ends, but for SepiSolar, our services include our community of knowledge about the latest solar and storage technologies, policies, manufacturer relationships, and our experience with AHJs around the U.S. and abroad.

As a community of engineers, we’re also great communicators with each other and our clients. We regularly share information and complement each engineer’s knowledge base. And while some firms may chain their engineers to CAD monitors with MC4 connection cables, our SepiSolar engineers can also act as independent engineering consultants, visiting solar project sites, ensuring quality, improving O&M or troubleshooting commissioning. We also consult with manufacturers, developers, asset managers and storage companies, providing the entire SepiSolar team with a comprehensive and continuous feedback loop of information from all over the solar industry.

In addition to formal consulting, our designers also informally consult with clients at the start of every project. During these calls, we take into consideration the company’s preferences and various skill sets. For example, a roofer who installs solar may feel comfortable drilling holes into a commercial rooftop but prefer microinverters for simpler electrical work. Similarly, an electrician may be very comfortable with optimized string inverters, but prefer a ballasted roof design to avoid roofing issues.

***

Naturally, there’s much more to tell about how SepiSolar grew over the last 10 years and why we’re so passionate about everything we do. Perhaps the best way to learn more is to set up a free consultation with me or just get a quote for your next solar or storage project. You can also join our SepiSolar community by simply following us on LinkedIn, Twitter or Facebook, or joining our mailing list. Please reach out for any questions or comments.

Josh Weiner is President and CEO of SepiSolar.

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March 27, 2018 2

 

Typically, the first figure developers and asset managers use to compare energy storage technologies is its dollar per kilowatt-hour ($/kWh) cost. But that seemingly simple metric may not be an accurate apples-to-apples one unless you’ve asked your battery manufacturer some important engineering questions.

To fairly compare the $/kWh cost of selected energy storage systems, we recommend your energy storage system designers ask the following four questions. In Part 2 of our series, we’ll explore technology considerations, applications and bankability.

Question 1: Is the battery vendor defining $/kWh in DC or AC watt-hours?

Storage, like solar, is becoming commoditized, so we need a common metric for pricing energy storage systems. Just like solar system dollars per watt pricing, you’ll need to have all vendors offer you pricing in either AC or DC kilowatt-hours. Their answers will lead to more questions; however, how are AC or DC kWhs defined? Which one includes the percentage of depth of discharge (DoD)? Are any parasitic loads included? What about DC-coupled systems, which may only have one inverter for both the PV and storage systems? Your engineer should know the answers to these questions to make a fair comparison of batteries.

Question 2: What about OpEx?

With batteries, it’s difficult to talk about capital expenditure (CapEx) without also talking about operating expenditure (OpEx). For instance, batteries are more expensive to maintain than PV systems due to their sensitivity to things like:

  • Temperature (battery HVAC systems require routine maintenance)
  • Fire suppression systems
  • Augmentation schedule (e.g., “capacity maintenance agreement” to replace degraded and failed battery modules over time as they wear out)

The last category mentioned above is particularly problematic due to the replacement schedule of batteries being closely tied to their use-case application. Some projects may require battery replacements within 5 years, while others in 12 years, and some last well beyond 20 years. Therefore, it’s important to take into account different duty cycles, technology choice, and specific use cases to determine the appropriate OpEx.

In addition, recent data has become available showing that actual battery performance is often different than what’s warrantied, which unfortunately translates into shorter-than-expected battery life spans, and, therefore, more cost to the project owner.

Moreover, considerations such as auxiliary loads, thermal management and round-trip efficiency (RTE) also degrade over time, resulting in higher battery system losses, and, therefore, less return on investment. These are all OpEx costs that can be carefully calculated and accounted for, but only when a thorough understanding of project economics and underlying product configuration and technology are combined to identify the true costs of ownership (more about this in question 3).

Question 3: Does your $/kWh figure include DoD and efficiency factors?

Similar to a solar panel’s STC and PTC ratings, batteries can also be subject to a lower kWh production when deployed outside the ideal conditions of a test laboratory. In addition to different temperatures, your battery’s actual $/kWh will also depend on its usage profile, recommended depth of discharge, power-to-energy ratio, calendar life, and other factors that an engineer should evaluate. Therefore, when calculating $/kWh, the kWh figure in the denominator needs to be corrected for the actual usable energy of the battery, not the nameplate.

For example, a 100 kWh battery that’s limited to a recommended 80% DoD will need to be calculated as 80 kWh. Additionally, your engineer should account for the battery’s 1-way efficiency, which could be as low as 86% in California, according to the 2016 Self Generation Incentive Program (SGIP) iTron report of average lithium-ion RTEs.

In this 100 kWh example, for the nameplate rating price of $500/kWh for a lithium-ion battery system in California, we could use the following formula to reveal the adjusted $/kWh that accounts for usable kWh energy for a $500/kWh quoted price:

$500/(80/100 x 86/100) ≈ $725/kWh … a 45% price increase!

Consequently, when someone quotes you a price in $/kWh, always ask the above questions, or at least ask if the price is calculated to include discounts for RTE and DoD. If their answer is, “Yes, we absolutely took that into account in that pricing,” then you’re set to compare apples-to-apples pricing. If they aren’t sure what you mean, or it’s not showing up in any purchase agreements or POs, then that’s a good indicator you need to double-check the fine print and perhaps do your own calculations or consult with an engineer to evaluate all the factors in your battery choice.

Question 4: What’s your levelized cost of energy (LCOE)?

As we’ve seen, regardless of whether the $/kWh number offered is in AC or DC watt-hours, or defined as OpEx or CapEx for tax purposes, the total cost of ownership picture is still incomplete.

As with total dollars-per-kilowatt solar PV system pricing, you’ll want your engineers to evaluate the total turnkey price that includes everything needed to be placed in service. In addition to the cost of the actual energy storage hardware, your LCOE figure will need to account for the cost of labor, engineering and feasibility studies, permits, utility interconnection applications and field studies, protection relays, total kWh throughput (including annual degradation of capacity and RTE), etc.

As long as your engineer has accounted for the above kWh questions and typical project costs, you’ll at least be able to make a somewhat-simple price comparison to evaluate your energy storage system. Of course, if you’d like the help of SepiSolar’s “solar enginerds” to evaluate your energy storage choices, please contact us.

To read Part 2 of our series about evaluating technology, applications and bankability, sign up for SepiSolar’s newsletter, or follow us on LinkedIn, Twitter or Facebook.

Josh Weiner is CEO and Founder of SepiSolar. Follow Josh on Twitter at @SepiSolarJosh

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March 15, 2018 0

Solar engineers love a good mystery to solve. A few months ago, our engineers overheard a phone call between one of our team members and a customer who was on a job site in Oregon. They were discussing the utility service and voltage of some very old, unlabeled service equipment. With zero photos from the site and not even so much as a voltmeter available to the field tech, we wrote down everything the field tech said, which amounted to a rather short description:

There are two lines coming in from the pole, then a big transformer and a small transformer. I can’t read the voltages, but then three lines go out to the main disconnect.

At this point, most engineering companies would dig their heels in and insist on knowing the line-to-line as well as line-to-neutral voltages (among other things) before proceeding with the designing. But SepiSolar didn’t balk; we jogged our brains together while sketching on the white board and searching the web, but were initially stumped.

But it was something about the different sizes of the transformers that stuck with us; we knew that was the key data point. In about 10 minutes, we were confident the site was utilizing an ‘Open Delta’ service from the grid, which taps only two phases of the utility grid but delivers a three-phase circuit to the facility. Knowing that a service like this is meant to handle most of the power demands on the two phases that come from the larger transformer, we opted to interconnect all the PV power to these two phases, leaving the power leg and smaller transformer alone. Solar engineering mystery solved.

Solving engineering and design mysteries and optimizing the system for a unique site like this is exactly the kind of challenge that SepiSolar’s engineers thrive on. In under an hour, we had a full system design for this customer and explained to him exactly how he needs to install this project safely.

If you’ve got a solar mystery that needs solving, call a SepiSolar “enginerd.” We’d love to solve it for you.

Click here to learn more about our solar consulting services.

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March 6, 2018 0

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

 

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

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

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

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

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

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

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

For additional readings, please see below:

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

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

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

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February 28, 2018 0

 

My fellow solar designers and engineers, make no mistake: We have been and will continue to be an important part of the world’s transition from fossil-fuel-based energy to a world that will be powered by interconnected and networked solar, wind, storage and integrated micro-grids. For those of you who don’t know what you’re getting into, welcome to the renewable revolution and hold on; it’ll be a bumpy ride! For those of you who already know the solar coaster, congratulations and thanks for your contributions! But … our contributions are far from over.

Energy analysts say that our full transition is inevitable, and that clean energy destiny can be accelerated by innovation, efficiency and improved designs, or just as easily decelerated by flawed, fossil-fuel biased or outdated policies, soft costs and careless designs that lead to bad publicity and damaged customers.

My fellow technical subject matter experts, you and I both know that such a transition is impossible without the minds and efforts of professionals like us doing our part. The sort of work we do is based on sound and well-understood scientific principles of math, engineering and technology.

Having studied these materials for quite some time, we know the power they can bring, as well as our responsibility to accelerate them—we are in a unique position to leverage these principles and the tools our industry has developed in order to make them ubiquitous and accessible to all through more streamlined and easy-to-use products and services.

Newton’s first law of physics states: “An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.” Similarly, I would say that the U.S. is transitioning toward 100% renewable energy at the same speed and direction that, while positive in direction, is not moving at a speed that will mitigate the worst effects of climate change, let alone pollution and its health effects.

Consequently, we need an unbalanced force to accelerate that transition, and my fellow solar designers and engineers, that unbalanced force can be you and me. We have the technical ability to accelerate solar + storage adoption and reduce its costs through better and more efficient designs, advocating for better policies, and combining our engineering thoughts. The more we can share best practices, surface the sometimes-nuanced and subtle policy roadblocks that slow our work, and educate policymakers and AHJs throughout the U.S. who are just beginning to see an interest in solar and storage, the faster solar and storage will be deployed and make a difference.

In short, engineers and designers must do our part and lead with our ideas and technical abilities, as well as contribute ideas to changing codes and standards. (Wouldn’t it be nice to one day actually have a truly national solar code?)

It’s for this reason we’re rededicating this SepiSolar blog to sharing solar and storage design and engineering best practices. We also know that this must be a collective effort, so we are opening our blog forum to any solar designer or engineer who also wants to share best practices and thought leadership toward our energy transition.

To contribute your thoughts, please email your posts to blogs@sepisolar.com. As long as it’s useful information (under 1000 words plus any related images, please) that helps to forward thought leadership on design, engineering or permitting for solar, energy storage or the grid, we’d love to publish it here, as well as share it on our social networks and email list. You’ll be fully credited—regardless of which company you happen to work for. From our perspective, solar designers and engineers are not competing against each other, we are competing against fossil fuels, dirty energy, apathy and current policies that stagnate our industry’s growth.

Thank you in advance for contributing, and we look forward to more solar design and engineering leadership.

Josh Weiner is CEO and Founder of SepiSolar

CA Small Business Enterprise

Certification ID:
2015743

Bidder/Supplier ID:
BID0068933

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

D-U-N-S number:
065817064
CAGE:
8F5K7

UNSPSC Code:
811024, 81101701, 81101516, 81101604, 43232614, 81101505




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