For a Solar PV Plant Developer, getting the Inverter up, charging the switchyard and pumping power to the grid has been the primary focus. Installing SCADA ( Supervisory Control and Data Acquisition) which is a computer-based monitoring and control system used to gather and analyse the real-time data from the PV plant is still an ‘optional’ task.
Its only after couple of years after the plant is commissioned, when the O&M team reports issues at the site that the plant owner realizes that monitoring is important to figure out the performance of the plant.
Based on Avi solar’s O&M field experience of more than 800MW PV plants, we analysed why is that most of the plants do not have a reliable plan monitoring system or SCADA. Here is a list of findings why the remote plant monitoring is not effective.
1. Leased line connections not working.
- Most SCADA needs a high bandwidth internet connection like leased lines, which are very expensive to maintain.
2. Developers have not renewed the AMC with SCADA supplier
- Many suppliers sold their system at low prices initially, but owners didn’t know that you need to pay a heavy premium every year.
3. Cables connecting the SCADA systems are damaged.
- Most traditional SCADA systems were interconnected using Kilometers of Fibre Optic / Copper cables, which have been damaged by unskilled labourers at the plant.
4. No Service / Support engineers visit the plant
- Many leading SCADA suppliers provide you telephonic support. But to resolve major issues you need to depute service engineers at these sites which are usually in remote areas.
5. SCADA is limited to control room only
- Many plants have a monitoring system at the control room, which means you are at the mercy of site engineer. Data accuracy and relevance could be at stake if the plant can’t be monitored remotely.
6. No String Level Monitoring
- Data collection is limited to Inverter monitoring only. String level faults cannot be detected.
The good news is that, there are retrofit solutions available which can replenish your existing SCADA and bring the plant data to your remote monitoring centre. IoT being the buzz word today, there are several options to get the data from your plant to the cloud in a cost-effective manner. There are several IoT platforms which can monitor data from PV plants. EagleSun SCADATM is one such platform exclusively developed for Solar PV Plants.
As the PV plant gets older, one needs to watch for performance degradations, losses due to aging of plant BOS like connectors, cables and terminations. Your SCADA needs to be operational and you need to have the plant data. It is strongly recommended that you monitor all the equipments, mainly the Inverter, Weather Station, String Combiner Box, Transformers, VCB and Energy Meters. If cost concerns exist for string-level monitoring, Zonal level monitoring solution can be considered.
The history of your plant will not only give insight into the performance parameters, it can also help you a great deal in forecasting & scheduling.