Shouldn’t the same hold true for PV installations?

Commercial PV projects are increasingly seen as secure long-term investment opportunities. Like any financial asset, PV systems must be monitored and managed to realise their full potential.

With traditional string inverters, O&M providers have access to limited information. String level or system level monitoring can indicate underperformance of the array, but little else. In order to inspect system issues, skilled technicians have to perform inefficient onsite troubleshooting on inverters operating under load and on DC lines at nearly 1,500V. They connect expensive equipment to the arrays in an effort to ‘sift through the tea leaves’ of complex IV trace curves to detect issues.

Fortunately, the standard in PV monitoring has been optimised. With MLPE (Module Level Power Electronics) devices, like power optimisers, O&M providers can remotely manage many of the issues. MLPE devices report module-level Voltage and Current at Max Power Point values on cloud-based monitoring platforms. This provides O&M companies high-resolution data on module-level performance to diagnose many issues, without the need to be onsite.

The most advanced PV monitoring and management solutions have the potential to take O&M from a manual, resource-intensive process to an automated, at-a-glance service. More than just a system overview, MLPE solutions deliver module-level insights and ensure a plant is performing to the best of its ability at all times. Intelligent, MLPE-supported cloud-based solutions also offer automated reports and alerts:

  • In-depth analytics and reporting on energy yield, system uptime and financial performance
  • Automated, pinpointed alerts for immediate fault detection
  • Remote diagnostics for smarter maintenance planning

For example, figure 1 identifies module 17 in string 1 of inverter 3 as underperforming compared to its neighbours. Module-level monitoring systems are able to detect underperformance like this and may be programmed to send automated alerts to the service providers.

Figure 1
  Figure 1

Once alerted to the underperformance, the solar installer, with just a couple clicks of the mouse, can gather more data on the power, voltage and current output of the problem module (figures 2 and 3). By comparing this module with others in the same array that are performing properly, the O&M provider can make determinations as to the possible failure modes.

 

Figure 2              Figure 3

Figure 2                                                                               Figure 3

With such precise data at their fingertips, solar professionals and system owners can now easily and accurately identify performance challenges (in the above case, likely a failed diode) and rapidly resolve problems. The result is a win-win; solar installers can more efficiently manage portfolios from a central location and identify problems before setting foot at the project site. This gives O&M providers a “Know Before You Go” advantage. They can load the ute with the correct parts to fix the issue the first time. Less on-site maintenance calls (also known as “site visits”) for the professional means a lower support cost and the ability to support more sites more efficiently. Plus, system owners win, with less system downtime eating into their profits.

Since the MLPE devices are persistently connected to the array, they are able to store data in the cloud for the system’s entire lifetime. By analysing historical project data in a monitoring platform (figure 4), such as SolarEdge’s cloud-based monitoring platform, module-level monitoring and management tools can also help stakeholders evaluate and predict system performance, and financial returns, for a given period. This comparative year-over-year snapshot enables smarter financial planning for the system owner.


Figure 4

Figure 4. Comprehensive performance data, with year-over-year comparisons

With a mature yet growing solar market, Australian solar PV owners and installers have recognised the need to minimise risk and make better-informed decisions on how to support their PV assets for 25 years or more. With the breadth of capabilities offered, it’s no wonder that MLPE devices connected to cloud-based monitoring platforms are taking root as a de-facto, dashboard-like solution for efficient problem solving, and an indispensable component of lucrative long-term PV investments.

 

Mr Lior Handelsman, VP Marketing and Product Strategy and Founder, is responsible for SolarEdge’s marketing activities, product management and business development. Prior to founding SolarEdge, Mr Handelsman spent 11 years at the Electronics Research Department (‘‘ERD’’), one of Israel’s national labs, which is tasked with developing innovative and complex systems. At the ERD he held several positions including research and development power electronics engineer, head of the ERD’s power electronics group and manager of several large-scale development projects and he was a branch head in his last position at the ERD. Mr Handelsman holds a B.S. in Electrical Engineering (cum laude) and an MBA from the Technion, Israel’s Institute of Technology in Haifa.