28 March 2018


Operations & Maintenance Data analytics Monitoring systems

Insights into components and plant performance

Author: Mina Mesbahi, Solarplaza

This webinar was organized in the run-up to the 4th annual edition of Solar Asset Management Asia, which will take place on 24 and 25 May 2018 in Tokyo. The full recordings of the webinar can be accessed on the event website

Meteocontrol, headquartered in Germany, is a pre-eminent PV monitoring company in the global market. The company’s track record includes distribution of monitoring systems to more than 43,000 PV plants. Meteocontrol offers additional services such as providing due diligence, consulting, forecasting and technical O&M.

Difference between Japanese and European monitoring

The typical Japanese monitoring systems visualise power generation and produce error alerts when necessary. This builds the foundation to assess the generation capacity and whether the product is functional. On the other hand, European monitoring systems analyse the measured data and evaluate the power generation. Not only does this type of monitoring indicate the amount of energy supplied, but it also examines whether the yield meets the expectations. 

Meteocontrol monitoring system provides all the software and hardware as well as a portal, which is crucial when evaluating the power generation.  All in all, it can be concluded that the Japanese model is not as complete as its European counterpart since it lacks further analysis of the data. Regarding the current party responsible for selecting the appropriate monitoring, 53% of the webinar attendees voted for EPC.

However, the attendees were asked at the end of the webinar about the most suitable party qualified to make that choice, the result of which varied significantly in comparison with their existing practice. 60% of the attendees voted in favour of the O&M service provider. 

This can be due to the fact that O&M providers and asset managers use the monitoring system, whereas EPC merely purchases the system, according to Santoki. Thus, O&M providers and asset managers should help EPC navigate the selection process of the most ideal monitoring system.

Evaluating the power yield from “Irradiation”

Firstly, the irradiation needs to be measured using data collected through pyranometers or weather stations. Furthermore, according to Santoki, this data should be measured in real-time and not based on an estimated value, for instance using extrapolated track record. 
Moving onto portal, the actual irradiation value measured at the site is then utilised to calculate the expected power generation. The final step would be to compare the actual power generation against the expected power generation.

Managing large portfolios

There is an abundance of big data from the PV system, which makes for an optimised overview of the system. According to Santoki, the essential KPIs to measure performance are: 

  • For O&M managers: 
    • Performance ratio (PR)
    • Open alarms, specific yield
    • Data availability
    • System availability
  • For asset managers:
    • Processing time of the maintenance
    • Reaction times of the operator
    • Invested time per “Asset”
    • Number of tickets per Portfolio
    • Fault Statistic

Reporting is the last relevant element and its typical applications consist of:

  • Data analysis
  • Information for investors
  • Portfolio overview for the O&M
  • Automated data extraction via API 

Challenge of automatic fault detection

The extensive amount of data in the system introduces the possibility of many information errors in the system, according to Santoki. For instance, an error on the system level sometimes solely shows the theory, when in reality the actual cause lies just within one single string. The resulting information should come into tickets, generated by the meteocontrol, for O&M operators. In  terms of risk assessment from big data, some statistics can be obtained from the tickets earlier mentioned. These stats can be provided by plant and utilised to identify the root cause as well as differentiating/ categorising in accordance with the corresponding time period.

How to optimise the maintenance process

Suffice it to say that, asset manager and O&M providers aim to minimise the costs of the operation. The meteocontrol system helps with optimising that process and O&M as a whole, through prioritising tickets for specific information errors. Then an engineer can be assigned to be dispatched using a smartphone, which facilitates the communication between the parties involved. The engineers then conduct the repair work at the site. Finally, the system can also provide feedback through a smartphone device. 

Interaction between PR Monitoring and CMMS

Performance Ratio (PR) monitoring along with Computerized Maintenance Management
System (CMMS) and asset management systems feed into the entire plant management pyramid. Santoki ends by highlighting that the aforementioned pyramid makes for the ideal monitoring system. 

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