Fronius Smart Solution: Introducing the Next Generation of Solar Systems

Wednesday, Aug. 23 at 2:00 PM EST

FroniusIntroducing the next generation of solar systems to the industry, the Fronius Smart Solution. The Smart Solutuon satisfies all needs for residential and commercial systems: flexible system design, shade mitigation, NEC compliance, high performance and state-of-the art monitoring while keeping the number of components low and installation easy.

In this webinar we cover the flexibility this solution provides and how to adapt it to your installations.


— Solar Builder magazine

Fronius offers up to $100 cash back on purchases in 2017 Summer Promotion

Fronius summer promotion

In honor of the solar summer season, Fronius is including a cash-back incentive on sales of Fronius inverters and Rapid Shutdown Boxes, directly provided to solar installers across the United States, as part of its Summer Promotion, running from on June 1 through August 31.

“Based on the success of last year’s Summer Promotion, Fronius knows that installers appreciate this incentive. As a result Fronius has decided to run a promotion again and this time include our commercial inverter, the Fronius Symo, as well,” says Wolfgang Niedrist, Director of Solar Energy.

The cash back is provided for every Fronius Primo, Symo and Rapid Shutdown Box that is installed, registered and connected to Fronius Solar.web between June 1 and August 31.

The Fronius Primo: $100 for every Primo 

With power categories ranging from 3.8 kW to 15.0 kW, the transformerless Fronius Primo is the ideal compact single-phase inverter for residential applications. The sleek design is equipped with the SnapINverter hinge mounting system, which allows for lightweight, secure and convenient installation.

The Fronius Symo: $100 for every Symo

Featuring various models ranging from 10.0 kW to 24.0 kW, the transformerless Fronius Symo is the ideal compact three-phase inverter for all commercial applications. The high system voltage and wide input range ensure maximum flexibility in system design.

The Fronius Rapid Shutdown Box: $50 for every box

The Fronius Rapid Shutdown Box provides the ultimate NEC 2014 code (690.12) compliant solution while enhancing rooftop and firefighter safety. With the Fronius Rapid Shutdown Box, Fronius offers a reliable and easy to install solution for Fronius SnapINverters.

Keys to inverter service: Data granularity, remote updates, customer relations

Fronius Solar.web

Fronius Solar.web is a free online monitoring platform for Fronius inverters. Remote diagnostics and alerts such as proactive email notifications and state code awareness are just two examples. The ability to view state codes remotely helps determine whether a truck roll is truly necessary or not. Recently added, Remote Update via Fronius Solar.web eliminates another category of O&M complexity and cost – making Solar.web the most useful manufacturer-designed platform on the market.

— Solar Builder magazine

Ask an Expert: Inverter manufacturers give us their best troubleshooting advice

Christopher Barrett

Christopher Barrett

Wi-Fi Can Cause Communication Issues

Christopher Barrett, director of technical services, APsystems

We often see issues our installers are facing related to communication, often due to misplacement of the gateway or an unreliable internet connection. Following best practices recommended by the manufacturer will help installers reduce repeat site visits to fix communication problems. Some of these best practices include installing a gateway in the correct location, which is typically a direct connection to the service panel in which the PV array home-run is landed (often a dedicated PV sub-panel). We also recommend using a wired ethernet connection whenever possible to better ensure reliable communication and minimize returns to the jobsite.

Ryan LeBlanc

Ryan LeBlanc

Double-check those Airways, String Lengths

Ryan LeBlanc, senior applications engineer, SMA America

  1. Over-voltage, strings that are too long, are the fastest way to kill an electrical device.
  2. Blocking airways, installing inverters too close to walls or other inverters, and not inspecting inverters regularly for a blocked air intake are both common. This results in less production, but it’s hard to say if it kills them earlier.
Frank O’Young

Frank O’Young

Pro Tip: Try Different Cable Colors

Frank O’Young, associate VP, Darfon

Our tech team sees that often the polarities of the DC lines from a PV module or string are incorrectly connected to the inverter due to the fact that same color cables (mostly black) are used for the + and – of the module or string. This can be avoided by using different cable colors for different polarities or checking the polarities before inverter connection. Our tech team also sees of that the L1 and L2 lines of the AC circuit are incorrectly wired when tying the inverter to the grid. Caution should be taken when connecting the L1 and L2 and instructions from the inverter manual should be followed.

RELATED: 2017 Solar Inverter Buyer’s Guide 

Mark Cerasuolo

Mark Cerasuolo

Storage is Complex – Get Trained to do it Right

Mark Cerasuolo, director of training and marketing, OutBack Power

Since our products and systems typically either include or interact with batteries, some training beyond what most grid-tie installers have is really necessary to ensure a safe and reliable installation. Even then, we really encourage installers to use pre-wired systems to ensure that the system is complete and wired correctly.

Ed Heacox

Ed Heacox

Top 4 inverter installation issues from CPS

Ed Heacox, GM, CPS Americas

  • “Grid V Out of Limit.” This is when the customer forgot to check that AC switch is on, so the inverter thinks the AC grid voltage is out of limit.
  • String mis-match. An inconsistent number of panels per string on one MPPT.
  • Exceeding DC/AC ratio recommendations. This can lead to occasional intermittent faulting.
  • Installing the DC string from left to right when it would be more ideal to balance the load across two MPPTs. This can lead to one MPPT too far out of balance from other MPPTs (e.g. four strings in No. 1 and one string into No. 2).
Peter Mathews

Peter Mathews

Watch your Connections, System Design

Peter Mathews, North American general manager, SolarEdge

Two very common errors are the improper mating of the connectors or reverse polarity. Other items that relate to the connectors include leaving connectors open during the installation process, which can lead to water penetration, or not fully crimping the wires. Another area in which we see support issues arise is in system design. For example, SolarEdge enables the installation of longer strings, so installers who are used to standard design constraints may out of habit design short strings instead of the 11.25-kWp strings that are available with the SolarEdge solution.

Brian Lydic

Brian Lydic

Inverter Integrity Starts with a Correct Installation

Brian Lydic, senior standards and technology engineer, Fronius USA

The most common installation oversights we see are related to torqueing, inverter location and moisture management. The mounting bracket must be installed on a surface to ensure there is no bowing or warping of the bracket. The wiring compartment must be wired as per guidelines to ensure a flush mating of the inverter body to the mounting bracket chassis. If wire routing or conduit fittings are not considered, there may be a loss of integrity in this seal. Pay special attention to the DATCOM cover. Make sure it “clicks” or “snaps” in place before screws secure it. If the cover is simply screwed in, there may be bowing and slight gaps between the inverter body and DATCOM cover, allowing water ingress.

— Solar Builder magazine

Inverter experts explain how to best calculate levelized cost of energy


Photo courtesy of APsystems.

Levelized cost of energy (LCOE) is one of the most important metrics used for judging the value of a PV system. It is also less easily understood and seemingly open to interpretation. How am I really calculating this figure? What is sitting outside this calculation?

Ask five inverter companies, and you might get five answers. So, we asked them all to get all of the answers.

Factor for Failure

A recurring theme when calculating LCOE for a PV system is getting a full understanding of its potential for failure and its ability to mitigate those losses: How many components are there? How likely are they to fail? When and how often could they fail? How much production will be lost during those failures? How much work is involved in getting it running again? This means keeping in mind variables like inverter replacement cost, system engineering cost, interconnection updates (adoption of new codes) and re-inspection cost.

Fronius Diagram

Fig. 1: Courtesy of Fronius USA.

Fronius did a study, examining the costs associated with replacing or repairing inverters 15 to 20 years from the present to account for that full PV system cost of ownership. An example they gave: If the original system cost is $10,000 and the extended cost factor is 1.10, then the total cost of the system over its lifetime is $10,000 x 1.10 = $11,000. Within this study, its SnapInverter resulted in 1.05 cost factor, while a generic string inverter hit 1.19 and a microinverter hit 1.26. The important variable in this calculation was mean time between failure (MTBF), defined in this study as the failure rate during the intrinsic failure period (see Fig. 1).

“Since the industry has grown so rapidly in recent years, the majority of PV systems in the United States are less than five years old, with typical standard inverter warranties being five to 10 years in length,” says Brian Lydic, senior standards and technology engineer at Fronius. “The majority of inverters installed in the field are still under warranty, and the industry has not needed to address large numbers of inverter replacements or repairs due to end of lifetime, though this will become commonplace.”

Yaskawa – Solectria Solar notes the correlation between the number of components and a higher MTBF, which makes sense intuitively. This makes the MTBF discussion a big part of the operations and maintenance (O&M) and LCOE calculation.

“The capability to service your inverter efficiently and in the most effective manner is crucial to keeping uptime high and calculating LCOE,” says Danielle Kershner, channel sales representative, Yaskawa – Solectria Solar, which keeps component count low by integrating AC/DC disconnects and integrates modular power stages to minimizes time and cost for service. The company has also revamped its customer service department to reduce downtime.

Another way to look at this is operational expenditure (Opex). The question answered here is “How much value am I losing during downtime?” So, Opex would include equipment failure, maintenance, repairs, materials and labor lead-time, restructuring, capacity change and so on. This analysis can favor microinverters in certain applications as any failures will only affect small portions of a system in a single moment, versus the entire system in the case of a string inverter failure. As mentioned in our feature on service on page 20, web-based monitoring services can be crucial for improving timeliness and efficiency of O&M functions.

“Since downtime is tied to the loss of generation, this variable must not be taken lightly when trying to maximize the LCOE,” says Frank O’Young, associate VP for Darfon. “The LCOE may be lowered by as much as 20 percent if the system uses equipment that is easy to maintain, quick to troubleshoot and requires minimal repair time.”

Look at Lifetime

Establishing all of the variables that add and subtract from the economic value of a PV system is step one. Establishing a timeframe is step two. Is your LCOE calculation really looking at the broad picture?

“When you compare two systems with a calculated LCOE, be sure the warranties are equivalent because the cost to replace a major component like a string inverter can have a serious impact on that calculation, particularly when those needed replacements occur once, or often twice within a 25-year period,” says Jason Higginson, senior director of marketing, APsystems, which has 10- and 25-year warranty options for its microinverters.

Adjacent to the warranty is service recovery speed. Ed Heacox, GM of CPS America, a leading commercial inverter company, says a key for them is having ready-to-go spares or RMA inverters available. “We are offering service speed commitments as well as onsite spares to help customers reach nearly zero downtime. Innovation of these commercial programs is a big part of our work on LCOE for customers,” he says.

Pika Energy Diagram

Example of “future-proofing” an install with a Pika Energy inverter.

Max Efficiency

Enough of all of this failure talk. Most of the time the system is going to be on and working, and when it is, it needs to be kicking ass and improving LCOE.

“One of the potential drawbacks is that LCOE calculations do not effectively differentiate between upfront and variable costs,” says Peter Mathews, North American general manager for SolarEdge.

His example: The fixed cost of a system, including customer acquisition, permitting and design, are realized regardless of the size of the PV system. Each added module can be installed for a much smaller variable cost.

“The trade-off between fixed and variable costs is more advantageous for systems with more PV modules since they can generate a disproportionately greater amount of energy versus the initial upfront costs,” he says. “LCOE calculations are therefore only part of the financial return. The calculation for return on investment (ROI) should also factor in the revenue generating potential of any site to generate cash from the PV system. The LCOE only calculates the expense. The returns can also vary based on region, rate structure or the ability to switch rate structures. Having a highly flexible PV solution that can add more modules onto projects is a powerful tool in maximizing the return on PV projects.

SolarEdge’s philosophy is to allow for the installation of modules in shaded areas and on roofs with varying angles. This degree of design flexibility means more modules per roof.

Marv Dargatz with HiQ Solar recommends stacking string powers high enough to maximize ROI while the system is up and humming. To do this right, he cautions to be wary of STC ratings.

“STC ratings for modules tend to be optimistic, partly because they are measured with a cell temperature of 25° C. In the real world, cell temperatures in direct sunlight are more likely to be at 60 or 70° C, yielding less power,” he says. “Overall, when orientation to the sun, temperature, time of year, soiling and aging are taken into account, strings put out a lot less power than STC leads you to expect. It’s therefore important to stack the inverter to make sure it is operating as near to its max output as possible to maximize ROI.”

He also says having a single MPPT per string rather than paralleling helps maximize harvest.

RELATED: How to achieve low LCOE utility-scale solar without cutting costs 

Seriously, Really Look at Lifetime

Pinpointing the lifetime of a system at 25 years from 2017 puts you into 2042. We did the math three times just because that number looks insane. We might all be in an Escape from New York post-apocalyptic future, but those PV systems will still be kicking, and one has to assume energy storage is going to be in a completely different position than it is now. And assuming that, you must assume your customers are going to want to move to upgrade to solar+storage, if they haven’t already, which throws all of your previous LCOE forecasting out the window of your 2042 flying car.

So yes, understanding cost and performance metrics for batteries is an important factor to consider today. Batteries introduce multiple new variables into the financial model and can have a positive or negative impact on LCOE depending on the technology used and how it is sized relative to the PV array and loads.

“A battery has both an instantaneous power rating [in watts or kilowatts] and an energy capacity rating [in kilowatt-hours] and they both factor into the financial model,” says Paul Dailey, director of product management, OutBack Power. “In addition, battery life is often expressed either in cycles or calendar life, but you need both metrics to determine the value of the battery in your application over time.”

The future of energy storage is why Chip Means, director of sales development, Pika Energy, says DC voltage is by far the most underrated and under-appreciated variable in LCOE.

“Too many solar inverter products use a low voltage range, typically 48 volts. Solar is rapidly changing to require the addition of battery storage behind the meter. Using 48-volt equipment simply doesn’t make sense for this evolving reality,” he says. “Low-voltage inverters are typically AC-coupled to add a battery to grid-tied solar, which requires using two inverters. This clunky, 48-volt arrangement means the customer’s roundtrip efficiency will be typically around 80 percent.”

Pika Energy’s products use an internal bus voltage of nominally 380 Vdc, and all of its components — PV Link solar optimizers, Islanding Inverters and Pika-compatible smart batteries — use this bus voltage to connect, communicate and transmit power. This results in a system with roundtrip efficiency of closer to 90-92 percent. That 12 percent increase on roundtrip efficiency pays major dividends in terms of LCOE.

Magnum Energy’s MicroGT inverter also comes ready to talk to the MS-PAE inverter/charger, to ease that solar-plus-storage transition.

“Installing storage-ready PV systems now will save significant time and resources when returning in the near future to add energy storage,” says Mike Dixon, sales and marketing director, Magnum Energy. “Not only considering current equipment investments, but future equipment investment — which doesn’t fall under the O&M umbrella — can save on the most expensive part of the solar formula.”

Unless all of these lifetime costs and realistic max output calculations are included and explained clearly to customers, a backlash will occur once they are surprised by replacement costs or any other unforeseen variable. And no one wants a line of customers wielding lightsabers outside their door in 2042, demanding satisfaction. 

This feature is from our March/April “Inverter Issue.” Get your FREE subscription to print here or digital versions here.

— Solar Builder magazine

The Holistic Home: We peer into the future of home energy generation, usage


The mid-term growth of the U.S. residential solar-plus-storage market will be nothing short of phenomenal, as the seamless melding of generation, storage and energy management emerges in single, overarching systems.

Yes, we might finally be headed there — the 1950s vision of the all-electric GE kitchen of the future, but driven by a touchscreen-controlled solar+storage system.

“The vision of the de-carbonization of both the energy grid and transportation is toward integration and aggregation,” says Wes Kennedy, a senior field application engineer at Fronius, based in Portage, Ind. “The homes of the future will have a solar system, a stationary storage system, networked appliances and an EV in the garage. These will be connected to a monitoring and control system that is grouped together with the neighboring homes and businesses.”

The aggregator, whether a utility company or a third party, will be able to use the distributed resource to stabilize and optimize the grid. The system owner will of course be compensated.

“Ultimately, using the network approach to energy, optimized with a communication and control backbone, is what will allow higher and higher levels of renewable energy to support the grid,” Kennedy continues.

RELATED: Primer for buying, installing residential solar+storage systems 

Storage System Boom

According to market research firm IHS, the energy storage market is set to explode to an annual installation size of 6 GW in 2017 and to over 40 GW by 2022 — from an initial base of only 0.34 GW installed in 2012 and 2013.
A handful of leading storage companies have already developed such solutions, but the current market may yet seem like a hodgepodge of confusing options for consumers.

“We’ve seen significant growth in the past few years related to energy storage. We expect the market to continue to grow over the next year, at a steady pace, and reach an inflection point somewhere between 2018 and 2022,” says Catherine Von Burg, CEO of SimpliPhi Power.

The smooth integration of solar panels, inverter, battery and software will elevate the current standard of residential solar-plus-storage solutions and inspire rapid market expansion.

“The solar-plus-storage market has been poised for significant growth, and from our vantage point, working on the solar and the storage side, we’re seeing the convergence of the technology, the pricing and the market drivers all materializing now,” says Chip Means, the director of sales development at Pika Energy.

The remaining limiting factor, Means suggests, has been finding the correct technology architecture for making solar-plus-storage simpler to install and with a more efficient yield for the customer’s maximized ROI over the lifetime of the system. For Means, the future is a single inverter solution with a DC bus that the batteries and PV share.

“That’s exactly why Pika made the Energy Island system — that’s the concept behind our approach, and that’s been helping to accelerate the market both on the installer and consumer sides. It’s all accelerating now,” he says.
One formidable task when incorporating storage is finding solutions that are agnostic as far as battery chemistry is concerned. One such solution is Pika’s new B Link, unveiled at Intersolar NA in 2016.

“Until now, broad adoption of solar-plus-storage has awaited mature battery solutions with the right mix of features, form factor and pricing. With B Link, virtually any conventional battery technology ranging from lead acid to lithium ion can be used to make a highly efficient, compact smart battery ideal for load shifting, demand response and backup power applications,” says Pika Energy president Ben Polito.

Tesla’s new PowerWall 2.0 has nominally doubled the energy density of the prior version, with 7 kW of power capacity and 14 kWh of energy storage; the inverter is supplied by three companies thus far: SolarEdge, Fronius and SMA. However, now that the SolarCity acquisition is complete, Tesla may build its own inverter for the residential market.

After three months, this solar-plus-storage estate in New York, powered by SimpliPhi Power and Lotus Energy, exceeded production estimates by as much as 23 percent.

After three months,
this solar-plus-storage estate in New York, powered by SimpliPhi Power and Lotus Energy, exceeded production estimates by as much as 23 percent.

Changing Behavior

The potential is there to change how homeowners think about and interact with their energy usage. The Energizr 200 from JLM Energy is one such example — a holistic solution that works in harmony with solar power and the conventional grid to meet a predetermined budget set by the homeowner.

“A significant benefit of the system is that it provides customers the ability to manage self-supply and time-of-use scenarios by combining solar and storage,” said JLM Energy founder Farid Dibachi, at the unveiling of the new system at InterSolar North America in July. “This is especially important in states like California, Arizona, Hawaii and Nevada where net metering is going away and residential demand charges are being added.”

JLM’s patent-pending Symmetric DC Regulation technology permits energy flowing from solar panels to charge batteries directly or directs it to bypass the batteries for immediate home use, eliminating unnecessary cycling and enhancing battery life. The system is managed by the company’s cloud-based software platform, Measurz, which automatically determines when energy should be used or stored and acts behind the scenes to meet a monthly budget set by the homeowner. The software analyzes user habits to come up with efficiency recommendations.

The Measurz mobile app enables remote control of appliances including HVAC systems and pool pumps that often cost the most to run. Energizr 200 tracks real-time energy consumption to create efficiencies that can be monitored from home or remotely, which can lead to more informed energy use decisions and cost savings.

Pricing in Free Fall?

Apart from ease of use, lower cost inevitably drives adoption. In the past two years, SimpliPhi has reduced the costs of its products by 30 percent, and this will only continue as economies of scale and production ramp up.

“We have been working with innovators in lithium ferrous phosphate chemistry, and others, to continue improving our performance profiles on energy density, cycle life, efficiencies and operating temperature range, such that we will be able to offer greater density and increased power output in the future, per kilogram and per square foot,” Von Burg says. “Also, we are forecasting even greater longevity with our products.”

Some companies have achieved even deeper cost cuts. Between 2011 and 2016, sonnen reduced its prices by 80 percent, and expects prices to decrease in the future.

“New financial incentives will also continue to help make storage even more affordable, while we expect to see the global production of batteries and storage systems, in particular, increase,” says Jannik Schall, the U.S. director for sonnen.

Pika’s Energy Island Inverter.

Pika’s Energy Island Inverter.

EV to play critical role

The U.S. adoption of electric vehicles has been slow, but long term, urban planners expect the EV to become the dominant form of transportation, and thus a cornerstone of the residential solar-plus-storage system.

“Integrating EV as a DC load or storage asset is a huge opportunity when you have a bidirectional DC bus. The car becomes an energy asset when it’s part of the nanogrid,” Means says.

The EV will not only be an important asset in the garage, but also away from home. “The fact that electric vehicles have the potential to become a two-way mobile power source and aid in a catastrophic event or provide backup power anywhere the car is opens up a world of new possibilities for storage and utilizing clean renewable power on the go,” Von Burg says.

In short, residential solar-plus-storage presents opportunities for energy efficiency and control like nothing that has come before.

“We expect smart storage to be the heart of a digitalized, energy efficient smart home while also providing the connection to the outside world: the grid,” Schall says.

This feature appeared in our January/February Innovations Issue. Be sure you have your FREE subscription.

Charles W. Thurston is a freelance writer who covers solar energy from Northern California. Reach him at

— Solar Builder magazine