KACO relaunches its portal for remote monitoring, now called blueplanet web

KACO new energy has relaunched its Internet portal for the remote monitoring of its solar PV systems. Since December 2018, the portal has appeared in a refreshed look under the name blueplanet web (formerly Powador-web). As part of the modernization, the Germany-based PV specialist is now offering users a mobile app as well as a free version for solar power plants with an output of up to 100 kWp.

kaco blueplanet monitoring
The company says its new monitoring portal serves operators of PV systems to recognize signs of unexpected yield loss and react quickly to that. Customers now have it even easier to keep an eye on the performance of their installation at all times and from anywhere.

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Free PV system monitoring up to 100 kWp

As before, KACO new energy’s PV system monitoring is available in a full-fledged ‘pro’ version as well as a free ‘public’ version. What is new is that blueplanet web public comes free of charge for solar arrays up to an output of 100 kWp; this applies to new registrations from Dec. 1 2018. The company also plans to integrate an alarm function that automatically informs about irregularities.

Full control with the app

In addition to a modern look that promises enhanced data digest, blueplanet web offers an up to date mobile app for iOS and Android. This allows remote monitoring of PV systems both from the desktop computer and at any time with a tablet or smartphone while on the move. After successful registration in the blueplanet web portal, the next step is to download the app free of charge; the login data for the portal then grants access to mobile system monitoring via the app as well.

Blueplanet web pro improves portfolio management as installers and maintenance services can bundle all their customers’ PV systems in one place. The possibility to personalize the user interface allows important data to be arranged according to individual requirements. Alarms are also part of the pro version – as are performance comparisons and reports.

— Solar Builder magazine

Inside the upgrades to the most powerful microinverter on the market (now shipping)

APsystems qs1 microinverter

Today’s solar systems require a more robust communication architecture to manage significantly more data points and in-field software updates, and this need was the driving force behind APsystems’s newest microinverter, the QS1, which is now shipping in the U.S. Despite being the most powerful microinverter you’ll find on the market, the QS1 debuted rather quietly at Solar Power International last year — a debut that even caught director of marketing Jason Higginson off-guard. But hey, when a product is ready, it’s ready.

Key to the QS1 development was incorporating a high-speed wireless Zigbee connection instead of Power Line Communication (PLC). The difference is measured in speed of both installation (75 percent reduction in installation time) and data transmission.

“With the smart grid, and a very smart inverter, there are a considerable number of data points that need to be communicated back from the microinverters through the gateway and to the monitoring platform in the cloud,” Higginson explains. “This means a steady stream of data is constantly flowing from the inverter to the internet. When systems like the QS1 and YC600 apply remote firmware upgrades, this creates a demanding bidirectional data flow and, for MLPE systems, traditional powerline communication isn’t going to cut it.”

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The QS1 employs high-speed wireless Zigbee, which is up to three times faster than conventional powerline communication (PLC), creating a local 2.4GHz mesh network for fast and reliable data communication between the microinverters and the gateway.

The QS1 is positioned to maximize high output PV panels up to 375 W by providing a higher peak output power (a microinverter-leading 300 W AC output per channel) and a wider MPPT voltage range (22V-48V) that allows for bettering tracking and energy harvest during low light conditions of dawn and dusk.

“It also features four individual MPPT so each PV module is managed and tracked separately, which means things that affect a single panel such as shading or debris do not affect the output from the rest of the panel even if they’re connected to the same microinverter,” Higginson says.

Compatibility

An APststems calling card is reducing the number of microinverter units needed per project. Only one QS1 unit is needed for every four modules (instead of the standard 1:1 ratio) while still providing four independent MPPT. This means fewer units to stock, transport and install while costing less than the equivalent of four individual microinverters. There are shared components that reduce the overall cost per watt by comparison.
But it’s not all shiny new performance numbers and doodads — APsystems kept the AC trunk cabling common with its dual-module YC600, which adds a hugely important flexible, mix-and-match compatibility on the same circuit to enhance site design capability and maximize circuit capacity.

“Using an even number of PV modules is ideal, however, with the APsystems 4-in-1 and 2-in-1 cost advantages, even if there are an odd number of PV modules in the array, leaving one side of a YC600 unused doesn’t significantly impact the cost per Watt of the system,” Higginson says.

Both microinverters also utilize the same gateways, so installers can choose the ECU-R for single or multi-residential installations or the ECU-C for applications requiring consumption monitoring and advanced contact/relay features.

“Compatibility with the existing YC600 microinverter system gives the QS1 an unprecedented advantage,” says APsystems chief technology officer Yuhao Luo. “Mixing dual and quad microinverters in the same system adds design flexibility while offering a strong inventory and installation labor advantage over conventional microinverters.”

— Solar Builder magazine

New standard emerging for grid operators to communicate with DER smart inverters

utility communication standard

A collaborative team published a new Application Note to help grid operators communicate with distributed energy resources (DER) and enhance use and value of energy storage and solar generation connected to smart inverters. Led by the Electric Power Research Institute (EPRI), the group includes the DNP Users Group, the MESA Standards Alliance (MESA), SunSpec Alliance, EnerNex, and Xanthus Consulting, and is funded in part by the California Energy Commission (CEC).

“DER are developing rapidly to provide new capabilities in serving customers and the grid. Yet without a standard way for utilities to communicate with new technologies, they cannot reach their full interactive potential,” said Ben Ealey, EPRI senior project manager and the project’s primary investigator. “We closed gaps in older communication models, which didn’t have the ‘words’ to command new capabilities of smart inverters and battery storage. We’ve added ‘new words’ for utility grid operators to use that can unlock emerging capabilities of DER, most specifically within the storage domain.”

This DNP3 application note integrates information from the latest field tests as well as smart inverter functionality and provides a standard information model for communicating with DER using Institute of Electrical and Electronics Engineers Standard (IEEE Std.) 1815TM– 2012 (DNP3) that complies with functional requirements in California Rule 21 and IEEE Std. 1547TM-2018.

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Generally, “application notes” provide examples of and suggestions for implementing standards in a specific domain of the industry. This Application Note contains a standardized list of DNP3 inputs and outputs and the specific mapping of information communicated within each point. It also includes functional definitions and mapping with the internationally recognized information model IEC-61850-7-420.

Given that relatively few newer DER have been installed, there has been limited adoption of standard DER information models for DNP3 systems. However, as the grid integrates more DER such communications models become essential for ensuring that utilities and the public are able to maximize the operational functionality and financial value of distributed and traditional grid assets.

Related developments

Prior to this project’s completion, MESA plans to update the MESA-ESS specification – a standard framework for utility-scale energy storage system data exchanges. The update will address configuration management, operational state, and functions applicable under the DNP3 profile for advanced DER functions. To support the application note’s implementation, SunSpec Alliance is developing a conformance testing framework to validate proper implementation in storage and solar systems.

This project continues through March 2019 and is funded in part by the CEC through the Electric Program Investment Charge (EPC-15-089), which funds clean energy research, demonstration, and deployment projects that support California’s energy policy goals and promote enhanced reliability and safety, at lower costs.

— Solar Builder magazine

Grid Neutral: How this DC transformerless inverter brings affordable off-grid power to the grid

sol-arkThe latest advancements in solar + storage systems have been a departure from the history in this category — mainly, doomsday preppers and hippies getting off the grid, man. No, the solutions of tomorrow are grid-tied but built to reduce a home’s dependency on the grid, using time of use strategies to shift loads to avoid the most punitive electric rates.

The sexiest solar + storage inverter advances in this area are DC transformerless options — a sole inverter capable of handling the PV, grid and battery connections. Because these inverters will be grid-connected, they prioritize continuous power efficiency instead of peak power. This is fine unless a customer is looking for an on-grid system that also can handle battery backup capabilities because that requires high peak power. There’s also the efficiency loss when converting from PV to battery and back to AC. An inverter starting at 97 percent efficiency could be at 92.2 percent or lower depending on the brand by the time the energy finally makes it to its destination.

So, yes, DC transformerless is a streamlined, future-proof architecture, but you will be making a compromise in efficiency somewhere. Well, except with the Sol-Ark inverter.

Peak vs. continuous

Sol-Ark is a new inverter on the block (or grid, I suppose). It is the brainchild of U.S. veterans looking to engineer a solution to help families be less dependent on the grid in an affordable way. They wanted to take the autonomy and top end abilities of the off-grid inverter without losing continuous power efficiency. To do this, Sol-Ark beefed up its hardware to minimize conversion losses. The result: Sol-Ark can deliver 96.5 percent efficiency in on-grid and 93 percent in off-grid and time of use scenarios with minimal conversion losses. On average, Sol-Ark needs 10 to 15 percent fewer solar panels and 5 to 30 percent less storage. That is serious savings.

“On our system, we have an internal 400-volt bus, and we convert high voltage solar panels to that 400 volts, and then that’s converted to AC,” says Tom Brennan, engineering manager for Sol-Ark. “When we go to the batteries, we focused on a super-efficient conversion method that allows us the highest efficiency directly into a 48-volt battery.” The end result is 95.5 percent efficiency from battery to AC.

Where many inverters in this space lag is in AC to battery efficiency. Outback, for example, is rated about 82 percent efficiency. Sol-Ark hits 96 percent efficiency because of a different methodology for pumping power in and out of batteries — a powerful 185 amp DC-to-DC charger.

Other DC transformerless options out there like Pika and SolarEdge are designed for newer 380-volt Lithium batteries. But Brennan notes these batteries are still 50 volts internally and require a double conversion every time going in or out of the battery. It’s why Sol-Ark has focused on just making 48 volt batteries more efficient.

Your on-grid customers might want storage as backup and to have power when the grid is down. This again is when peak power is crucial to handle motors starting up. For example, SolarEdge and Outback Skybox are not off-grid solutions. They only deliver 5 kW on the battery and little additional peak power means they can’t start up A/C or well pumps. Pika has a per string optimizer, and if you don’t use it, it won’t work off grid because it’s not an AC-coupled system.

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The reason Sol-Ark has so much peak power is it packs in twice as many components as its competitors. It is literally designed to survive a solar flare or EMP attack, which was the goal for these U.S. vets at the outset.

“We didn’t just focus on the person who wants to save on an electric bill but focused on emergency responders and state government, but in an affordable manner,” Brennan says. “To do this, we basically built a 20-kW inverter and throttled it down. We don’t have heating issues because we are not taxing the system.”

Providing the most powerful, efficient inverter for on or off-grid solar + storage does come with some new school drawbacks, at least right now. For example, Sol-Ark does not meet California’s Rule 21 criteria.

“That has not been an issue because we just don’t export power in California,” Brennan says. “We use the solar during the day, batteries at night and grid as a backup.”

On-grid extras

Sol-Ark comes ready to perform the typical on-grid capabilities like time of use and grid sell back but also has a few unique options:

Limited home mode. CTs or current sensors are placed on the mains of the house, and instead of just full grid selling or only powering critical loads, limited home mode is an in-between option. The CTs sense when any other circuit not on the critical loads panel kicks on and ramps up the solar power as much as it needs to zero the meter if it can.

“Maybe you don’t have a net meter agreement to sell back power to the grid, but you can push power to your whole house as long as the grid is up,” Brennan says. “If it’s down, you can only run critical circuits. We designed Sol-Ark 8K for seamless on-grid capability.”

A lot of people in rural areas take advantage of this because they either don’t want to deal with the electric company or have no incentive to deal with it, so they use that to push as much power as they can to the house.

Smart loads. This is a programmable load that’s not based on time but rather the batteries’ state of charge or how much PV power is being produced. Brennan explains: “We can turn on A/C or the hot water heater at 100 percent battery and solar is producing 2,000 W during the 9 a.m. to 3 p.m. time range when I’m producing excess solar. And if the solar stops producing [or batteries get to 95 percent], they shut off automatically. It’s perfect for on-grid time of use and off grid for preserving battery life.

Hot water heating takes about six panels of energy a day, and air conditioning can take about 12 panels a day, so if just those can be run from PV alone and without the batteries, that will extend the life of the batteries by at least 50 percent or more and probably reduce the battery bank size by 30 percent. The Sol-Ark system will also account for and adjust to the degradation of battery health over time.

What’s old is new again

Another question Brennan asks: Why are solar + storage customers waiting for lithium prices to drop when they will be connecting to the grid anyway? Sol-Ark’s goal is make an off-grid approach to solar + storage work on the grid without doubling the cost of a system.

“We don’t think customers need lithium if it’s just sitting there for backup; it’s a waste of money,” he says. “If you are on the grid, then take advantage of it. You can go with lower cost AGM batteries that last 10-plus years. If you have the grid where you are, get AGM batteries and use them as backup or slightly used and don’t necessarily deep cycle them. If you’re totally off grid, then we recommend lithium or carbon-based AGM that have four to five times the cycle life. You can minimize your usage of the grid, but do it to keep your battery bank at a reasonable cost/size. If you were to try going completely off grid with a traditional size home, the battery cost would make you cry.”

Chris Crowell is the managing editor of Solar Builder.

— Solar Builder magazine

SolarEdge EV-charging inverter now works with Google Assistant

SolarEdge EV charger inverter

SolarEdge says its EV-charging solar inverter — already the first of its kind out there — now works with Google Assistant to make EV charging simpler for consumers and to better integrate all smart home solutions.

“Smart homes have mainly been about convenience and interconnectivity, but the next step of the smart home is integrating smart energy management, such as EV charg-ing,” stated Lior Handelsman, SolarEdge’s Founder and VP of Marketing and Product Strategy. “By merging the simplicity of smart homes with the value of smart energy through this collaboration with Google, SolarEdge is leading the way in making the power of smart solar energy more accessible to more people”

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Consumers can now tell the Google Assistant to start and stop EV charging. SolarEdge plans to add functionality to the Google Assistant commands, including inquiring about charging status, checking average miles charged in the charging session, and pre-schedule charging.

SolarEdge’s EV charging solar inverter offers up to six times faster charging than standard Level 1 chargers through its innovative solar boost mode.

— Solar Builder magazine