Keep Watch: How the PV monitoring landscape is evolving

Cloud Computing

Monitoring systems have become an integral and ubiquitous component to any well-functioning PV project for years now. As the industry has matured, monitoring ecosystems have evolved from OEM-provided, HMI-style interfaces reminiscent of traditional Supervisory Control and Data Acquisition (SCADA) systems to modern web apps slinging the latest tech buzzwords.

However, much of the innovation in PV monitoring has been on the software side, with the data collection skeleton remaining largely unchanged. While many of the monitoring software platforms offered to the market have had numerous facelifts and new feature bundles released, the industry as a whole has not successfully utilized many of the new data collection (e.g. low-cost wireless sensors) and analysis techniques (e.g. machine learning) that have gained significant traction in other industries. This lack of true innovation has contributed to a negative perception of monitoring companies throughout the industry.

Equipment-direct

Solutions for monitoring PV systems sit on a spectrum. At one end, corresponding to low-cost and low-touch, is equipment-direct monitoring. Most inverter manufacturers and an increasing number of combiner box and meter manufacturers offer integrated monitoring platforms that consist of a web portal where equipment data is displayed. This is usually provided free of (additional) charge by the OEM, and may have basic features such as alarming, visualization and reporting.

The downside here is monitoring is not the primary goal of the manufacturer. Given the choice between spending a development budget on a better inverter or a top-tier inverter monitoring platform, the inverter manufacturer will usually work on their core technology. The burden to the end user when using these equipment-direct monitoring platforms can be significant. For example, it’s not unheard of to have multiple makes of inverters or combiner boxes at a single site, and it’s nearly impossible to find an operator who is responsible for a fleet of assets that use a single manufacturer. Having to log in to multiple platforms can quickly become unwieldy and does not scale well.

SCADA

On the opposite end of the spectrum from equipment-direct monitoring is a fully custom-built SCADA system. These systems are tailored to a particular plant (a single SCADA system is rarely used to monitor and control multiple plants), and the implementation for a given system is not repeatable for another system.

The combination of equipment required for a SCADA system is unique to a given plant, and the configuration and software to interface with the equipment is custom developed for each implementation. This often results in high costs due to the non-repeatability of the solution. Support for these systems can be limited as the business model is based on one-time integration and setup fees. But many SCADA integrators have years of proven success, and, while not unheard of, it’s rare that significant bugs exist in the delivered solution. The commissioning of a SCADA system is usually robust and thorough, which will catch any configuration errors in the process.

Depending on the size and locality of the PV project, SCADA may be required to allow a third-party (the local utility or reigning RTO, for instance) control over the equipment on site. There may be regulatory requirements to allow these third parties to send commands to the site, ordering inverters to lower their output, increase reactive power, or turn off should the grid require additional stability.

How to optimize performance and profit through O&M monitoring

Cloud-based Remote Monitoring

The space between a low-cost, low-touch, manufacturer-based monitoring system and a high-cost, high-touch SCADA system is inhabited by third-party remote monitoring systems. These are generally software-as-a-service products usually hosted in the cloud. Cloud-based remote monitoring has quite a few advantages over equipment-direct monitoring.

For one, it allows a single operator to monitor and respond to many projects concurrently. Another advantage is that providing monitoring solutions is the primary objective of these companies. If a monitoring company provides a subpar product, there’s little chance for success or repeat business.

There are advantages over traditional SCADA systems as well. Since the cost of development is spread across many customers, they are usually lower cost than SCADA, and many modern systems are now able to offer the same level of control that a SCADA system would.

Cloud-remote monitoring systems are also more flexible, updated more often, and are scalable across fleets of projects. There are concerns about security, however, which in many applications is of paramount importance. Few offtakers are comfortable with cloud-based control systems due to the perceived vulnerability from hackers. Many utilities have a mindset that is distrustful of unproven innovation, and are less likely to accept a solution that has not been proven for years or even decades.

Traditional Monitoring Challenges

In addition to the challenges each technology faces, there is a physical consideration as well. The majority of traditional solutions require hardwired connections to collect and transport data to either the point of consumption or a data backhaul. This adds additional cost to purchase the wires over which the data will be transmitted and adds in an additional possible breakpoint. The main barrier to adopting wireless communication networks has been reliability and security.

Another weakness of these traditional monitoring and management systems is the methods by which data is transferred. Most traditional monitoring systems use communications protocols that were intended for humans to communicate to one another via devices. Extraneous metadata is often included in these

data transfers, which inflates the size of the messages and thus the bandwidth requirements per datapoint sent. By moving to a machine-to-machine protocol, better efficiency can be achieved in data transfer, which helps to reduce operational costs of data collection. It can also assist in reducing latency of data and commands, which leads to a more responsive and safer site.

Modern Monitoring

All of those concerns have been major drivers of the adoption of Internet of Things (IoT) technologies across other industries. These lessons can be translated to the PV industry. Optimizing data transfer for PV plants is not a simple task though. Bandwidth requirements vary from project to project. If string data is being captured at a particular site, the amount of data being transferred can be orders of magnitude larger than a site where only inverters and meters are being monitored; if panel-level data is available (from microinverters, DC optimizers or other MLPEs), the amount of data can be orders of magnitude larger yet. To ameliorate these issues, many IoT platform providers utilize modern machine-to-machine communications protocols like MQTT that help to reduce the size of data packets allowing for more data to be sent over the same bandwidth.

Further complicating data transfer is both the location and the topology of the project. Many large-scale PV projects are located in remote areas, which may not have readily accessible ISP coverage or cell service. Local communications interference can also be a problem, whether this interference stems from electrical sources, such as the feedback coming from the inverters, or physical sources, such as being blocked by panels.

These concerns can be alleviated by using a combination of technologies within a single plant’s network topology. Such technologies can include WiFi, cellular 2G/3G/4G, Zigbee mesh networks, and even low power WAN technology such as LoRa. However, this concept contrasts with traditional monitoring providers, who generally only use a single communications technology across all of their customers regardless of plant topology and location; since these solutions are nontrivial to implement, it’s often only cost effective for these providers to choose the most applicable communications technique and stick to it.

IoT-based Solutions

Applying IoT concepts to PV monitoring can help alleviate some of the challenges that stem from traditional monitoring applications. Most IoT platforms give users the ability to deploy logic to edge devices — the inverters, meters and other equipment located on site. Granted, this isn’t a new development as many monitoring and SCADA providers are already deploying intelligence to the devices in the field, but in an IoT environment, rather than utilizing expensive dataloggers or industrial computers, edge intelligence can be provided via an inexpensive Raspberry Pi, Arduino, or similar small computing device.

Moving diagnostics to the edge provides additional benefits when used in conjunction with an IoT-based monitoring application. For instance, there are a subset of faults that will always require a site to be disconnected from the grid. By moving to an IoT-based solution using lower-cost edge computer hardware, the latency between fault occurrence and shutdown can be reduced relative to that achieved with a high-cost SCADA system. When edge computing is coupled with machine-learning and cloud-based analytics, PV monitoring systems can become more autonomous, allowing not only automated investigation to the root cause and failure area of fault events, but actions such as technician dispatch or site-level disconnect.

The trend of monitoring system evolution over the past 10 years has been to bring prices down, resulting in a commoditized solution that favors innovations in flashy software features rather than a rethinking of the framework around which a monitoring system is built. By looking to emerging technologies, monitoring providers can challenge these assumptions yielding a lower-cost yet higher-functioning monitoring solution. Such an evolutionary step is now coming to the market in the form of IoT-based solutions, which will enable better efficiencies and lower operational costs in monitoring and managing a PV project.

Beau Blumberg is solution director swiftPV, infiswift.

— Solar Builder magazine

Project of the Year 2017 voting: Commercial & Industrial category

California Department of Franchise Tax Board

Sacramento, Calif.  |   3.6 MW

Baja Construction Franchise Tax Board Aerial - 1

The Franchise Tax Board complex is one of the largest business campuses in northern California, which makes this the state’s largest carport installation (10,400 PV panels), covering 1,276 employee parking spaces, spanning over 622,000 sq ft! Baja’s specialization in pre-engineered, pre-fabricated high-tensile light gauge steel structures for solar carports made the project possible.

Developer: DGS-Building Property Management
Contractor: Ecoplexus, Inc.
Modules: SolarWorld [SW 280 Mono]
Inverters: SMA STP
Mounting: Power Solar Frames

Head to the voting booth


 

Kam Man Foods

North Hanover, N.J.  |  600 kW

Kam Man Foods, the leader in Asian supermarkets in the Northeast United States, began solar-powering its buildings in 2012 with a 265 kW system. Fast forward to 2017, and Amergy Solar was contacted by the company to work on a new project that would maximize roof space and get as much power as possible. This project moved away from traditional South facing systems and used an East/West orientation. The racking used was Everest Solar’s third generation of the D Dome ballast system, which was specifically designed for an East/West orientation and higher density without needing roof penetrations. In the end, the project hit 600 kW.

Developer: Amergy Solar
Contractor: United Solar Associates
Modules: REC
Inverter: Solar Edge
Mounting: Everest Solar Systems

Head to the voting booth


 

Mission Park Funeral Chapels and Cemeteries

San Antonio  |  530 kW

project of the year solar

project of the year solar mission

Freedom Solar installed more than 530 kW of solar power across seven locations of Mission Park Funeral Chapels and Cemeteries, the largest and oldest privately owned funeral company in San Antonio. Because funeral homes operate 24 hours a day, seven days a week, electric bills are a large portion of their operating costs. The new solar projects will offset more than 55 percent of Mission Park’s electricity needs at the seven locations, which include two mortuaries, its corporate office, three funeral chapels and cemeteries and a funeral home. One of the most unique designs was the 80-kW system installed at the Mission Park North Funeral Home. Freedom used SunPower panels that were laid out and slightly raised in a “helix design” to eliminate inner row space and shadows.

Developer: Freedom Solar
Contractor: Freedom Solar
Modules: SunPower
Inverters: SMA
Mounting: SunPower

Head to the voting booth


 

Ohio Northern Array

Ada, Ohio

Ohio northern solar array

Single Axis tracker array on 12 acres of ground supplying 10% of electricity for Ohio Northern University. Also used on campus for educational purposes. ONU educates engineering students based on 21 century project based learnings around the principals of photovoltaics and solar practical experience.

Developer: GEM Energy
Contractor: GEM Energy
Modules: First Solar
Inverters: SMA
Racking: SunLink

Head to the voting booth

 


Old Port Parking Garage

Portland, Maine  |  194 kW

Quest Renewables - Fore St_10

The 194-kW system is the first solar parking garage canopy in the state of Maine. The system is on the top level of the Fore Street Garage and provides shaded parking and cover from the elements for vehicles and provides clean, local, renewable energy to the Hyatt Place. The highly efficient, 90 percent ground-level construction of QuadPod allowed the system to be built in just eight days from start to finish – record time for a parking canopy. The system will offset more than 23 percent of the hotel’s electrical consumption.

Developer: East Brown Cow Management
Contractor: ReVision Energy
Modules: Hyundai 350
Inverters: Chint String
Mounting: Quest Renewables

Head to the voting booth


 

Urban Health Plan “Solar Wall”

Bronx, N.Y.

Urban Health solar wall

The solar wall is innovative because it solved the urban solar problem of insufficient roof space.
New York City solar installation leader Quixotic Systems has designed an innovative solar solution in the heart of the Bronx at Urban Health Plan’s Simpson Pavilion. Unlike most rooftop systems, the 37-kW array has been installed on the side of the building – a “solar wall.” The PV system designed and installed by the team at Quixotic foregoes limited roof space in favor of the Bronx building’s south-facing four-story façade. The high-efficiency array features 104 SunPower 327 panels mounted on a custom vertical rack.

Developer: Quixotic Systems Inc.
Contractor: Quixotic Systems Inc.
Modules: SunPower
Inverters: Fronius
Mounting: Custom

Head to the voting booth


 

Worcester Greenwood Landfill

Worcester, Mass.  |  8.1 MW

worcester landfill solar project

This is the largest municipally owned landfill project in New England. Stretching across 25 acres, the Greenwood Street Solar Array is a $27 million project that is expected to pay for itself in six years and save the city $60 million over its expected 30-year life span. It will produce enough energy to power 1,340 homes per year.

Developer: Borrego Solar Systems
Contractor: AJ Virgilio
Modules: LG Electronics
Inverter: SunGrow
Mounting: SunLink

Head to the voting booth

— Solar Builder magazine

Project of the Year 2017 voting: Commercial & Industrial category

California Department of Franchise Tax Board

Sacramento, Calif.  |   3.6 MW

Baja Construction Franchise Tax Board Aerial - 1

The Franchise Tax Board complex is one of the largest business campuses in northern California, which makes this the state’s largest carport installation (10,400 PV panels), covering 1,276 employee parking spaces, spanning over 622,000 sq ft! Baja’s specialization in pre-engineered, pre-fabricated high-tensile light gauge steel structures for solar carports made the project possible.

Developer: DGS-Building Property Management
Contractor: Ecoplexus, Inc.
Modules: SolarWorld [SW 280 Mono]
Inverters: SMA STP
Mounting: Power Solar Frames

Head to the voting booth


 

Kam Man Foods

North Hanover, N.J.  |  600 kW

Kam Man Foods, the leader in Asian supermarkets in the Northeast United States, began solar-powering its buildings in 2012 with a 265 kW system. Fast forward to 2017, and Amergy Solar was contacted by the company to work on a new project that would maximize roof space and get as much power as possible. This project moved away from traditional South facing systems and used an East/West orientation. The racking used was Everest Solar’s third generation of the D Dome ballast system, which was specifically designed for an East/West orientation and higher density without needing roof penetrations. In the end, the project hit 600 kW.

Developer: Amergy Solar
Contractor: United Solar Associates
Modules: REC
Inverter: Solar Edge
Mounting: Everest Solar Systems

Head to the voting booth


 

Mission Park Funeral Chapels and Cemeteries

San Antonio  |  530 kW

project of the year solar

project of the year solar mission

Freedom Solar installed more than 530 kW of solar power across seven locations of Mission Park Funeral Chapels and Cemeteries, the largest and oldest privately owned funeral company in San Antonio. Because funeral homes operate 24 hours a day, seven days a week, electric bills are a large portion of their operating costs. The new solar projects will offset more than 55 percent of Mission Park’s electricity needs at the seven locations, which include two mortuaries, its corporate office, three funeral chapels and cemeteries and a funeral home. One of the most unique designs was the 80-kW system installed at the Mission Park North Funeral Home. Freedom used SunPower panels that were laid out and slightly raised in a “helix design” to eliminate inner row space and shadows.

Developer: Freedom Solar
Contractor: Freedom Solar
Modules: SunPower
Inverters: SMA
Mounting: SunPower

Head to the voting booth


 

Ohio Northern Array

Ada, Ohio

Ohio northern solar array

Single Axis tracker array on 12 acres of ground supplying 10% of electricity for Ohio Northern University. Also used on campus for educational purposes. ONU educates engineering students based on 21 century project based learnings around the principals of photovoltaics and solar practical experience.

Developer: GEM Energy
Contractor: GEM Energy
Modules: First Solar
Inverters: SMA
Racking: SunLink

Head to the voting booth

 


Old Port Parking Garage

Portland, Maine  |  194 kW

Quest Renewables - Fore St_10

The 194-kW system is the first solar parking garage canopy in the state of Maine. The system is on the top level of the Fore Street Garage and provides shaded parking and cover from the elements for vehicles and provides clean, local, renewable energy to the Hyatt Place. The highly efficient, 90 percent ground-level construction of QuadPod allowed the system to be built in just eight days from start to finish – record time for a parking canopy. The system will offset more than 23 percent of the hotel’s electrical consumption.

Developer: East Brown Cow Management
Contractor: ReVision Energy
Modules: Hyundai 350
Inverters: Chint String
Mounting: Quest Renewables

Head to the voting booth


 

Urban Health Plan “Solar Wall”

Bronx, N.Y.

Urban Health solar wall

The solar wall is innovative because it solved the urban solar problem of insufficient roof space.
New York City solar installation leader Quixotic Systems has designed an innovative solar solution in the heart of the Bronx at Urban Health Plan’s Simpson Pavilion. Unlike most rooftop systems, the 37-kW array has been installed on the side of the building – a “solar wall.” The PV system designed and installed by the team at Quixotic foregoes limited roof space in favor of the Bronx building’s south-facing four-story façade. The high-efficiency array features 104 SunPower 327 panels mounted on a custom vertical rack.

Developer: Quixotic Systems Inc.
Contractor: Quixotic Systems Inc.
Modules: SunPower
Inverters: Fronius
Mounting: Custom

Head to the voting booth


 

Worcester Greenwood Landfill

Worcester, Mass.  |  8.1 MW

worcester landfill solar project

This is the largest municipally owned landfill project in New England. Stretching across 25 acres, the Greenwood Street Solar Array is a $27 million project that is expected to pay for itself in six years and save the city $60 million over its expected 30-year life span. It will produce enough energy to power 1,340 homes per year.

Developer: Borrego Solar Systems
Contractor: AJ Virgilio
Modules: LG Electronics
Inverter: SunGrow
Mounting: SunLink

Head to the voting booth

— Solar Builder magazine

Vote here for the 2017 Solar Builder Project of the Year

Solar Builder Project of the Year awards

Finally, a vote in which there are no losers.

From remote islands to abandoned mines, from sprawling plains to dense urban areas — this year’s crop of Project of the Year Award nominees might be our most varied yet. This year, we decided to break out three separate categories – commercial & industrial, utility-scale, solar + storage – to best capture the breadth of entries and to let their unique attributes shine. After two weeks of voting – on Sept. 22 — we will close those polls, tally the votes and declare winners.

But then [twist!] we will reopen the polls and have the three category winners battle it out for a one-week, winner-take-all vote to choose the true Project of the Year, which will be displayed on the cover of our November/December print magazine.

The polls are on this page. Please click through to the three category links below, read about the nominees, and then come back here to cast your ballot.

Commercial & Industrial nominees

Utility-scale nominees

Solar + Storage nominees

2017 Project of the Awards round 1







— Solar Builder magazine

Vote here for the 2017 Solar Builder Project of the Year

Solar Builder Project of the Year awards

Finally, a vote in which there are no losers.

From remote islands to abandoned mines, from sprawling plains to dense urban areas — this year’s crop of Project of the Year Award nominees might be our most varied yet. This year, we decided to break out three separate categories – commercial & industrial, utility-scale, solar + storage – to best capture the breadth of entries and to let their unique attributes shine. After two weeks of voting – on Sept. 22 — we will close those polls, tally the votes and declare winners.

But then [twist!] we will reopen the polls and have the three category winners battle it out for a one-week, winner-take-all vote to choose the true Project of the Year, which will be displayed on the cover of our November/December print magazine.

The polls are on this page. Please click through to the three category links below, read about the nominees, and then come back here to cast your ballot.

Commercial & Industrial nominees

Utility-scale nominees

Solar + Storage nominees

2017 Project of the Awards round 1







— Solar Builder magazine