Importance of Condition Monitoring in Renewable Energy Asset Management (Photovoltaic Solar Plants)
Asset management – Myth Vs Reality
Shining sun and cleaned modules are the basic requirements to make the PV solar system work effectively but that is not all. When we think about the minimal maintenance and operational efforts, most of us forget about the risk involved in financial, operational, and technical aspects of it. Shining sun and an active asset manager are necessary but are not enough to experience the robust operation of the system. Reducing volatility, through the stabilization of operations, and enhancing performance, through the optimization of the sites to increase their longevity can give the best results and power generation at the highest capacity.
Currently followed practices in RTPV Asset Management
Cleaning of Modules
Current practice
It is being understood if the modules are cleaned and weather conditions are good the generated energy will be high. This is not untrue but it is not completely true. Cleaned modules help in better energy generation but are not solely responsible for it.
Generally, modules are being cleaned based on the cycle & time period they are told by the companies.
Corrected practice
It is important to follow the cycle mentioned but following it irrespective of focusing on other important parameters can be a problem. Loss of generation can’t be possible due to the dirt factor only. The following mentioned factors can also be responsible
- Angle of temperature
- Analysis of the generation report
- Irradiance level
- Availability of cleaning resources like water supply, manpower/robot
By considering above mentioned parameters along with the generation pattern the cleaning cycle can be decided and followed for an effective outcome.
Extraction of Online Report
Current Practice
Normally the online generated report is been compared with the commitments provided by the O&M consultant and only the energy generated parameter is being focused on. No doubt it is the most important factor.
Corrected Practice
Focusing on only generated energy is not going to help as it doesn’t define the overall condition of the system. Proper and continuous analysis regarding
- Overall performance of the system/plant
- Thermal/fault pattern of the equipment
- Aging for equipment/system
- Environmental parameters like pollution, climate, etc
Should be there to figure out the reason for the generation loss. Through this analysis, one can take corrective actions to prevent the overall system from damage.
Carryout Compliance based Condition Monitoring/Testing
Current Practice
Normally, compliance-based testing is carried out to match with the laws and regulations in an appropriate manner. Companies follow it or get it done based on the timeline given.
It is necessary to carry out compliance-based testing but not at the cost of losses the required downtime is incurring. Companies fail to perform analysis before going for compliance-based testing.
Corrected practice
Before opting for compliance-based testing it is crucial to analyze some factors. Let’s understand it in a simple way –
| Parameters | Scenario 1 | Scenario 2 |
| Downtime | 100 Hours | 80 Hours |
| Number of Faults | 25 | 3 |
| Generation Loss | 30,000 Units | 37,000 Units |
| Replacement Expense | 4.5 Lacs | 12 Lacs |
| Water Usage | 2.5 Lac Litre | 2.3 Lac Litre |
Case l
Generation Loss – 30,000 Units * 4.30 (Per unit charge) = Rs. 1,29,000
Replacement expense Rs. 4.5 Lacs
Water Usage – 2,50,000 Litre * 0.033 (Per litre price) = Rs. 8,500
Total – 5,87,500
Downtime 100 Hours, No. of faults 25, other expense Rs. 5,87,500
Case ll
Generation Loss – 37,000 Units * 4.30 (Per unit charge) = Rs 1,59,000
Replacement expense Rs. 12 Lacs
Water Usage – 2,30,000 Litre * 0.033 (Per litre price) = Rs. 7,590
Downtime 80 Hours, No. of faults 3, other expense Rs. 13,66,590
Analysis
Now from the above-mentioned data, one can select scenario 2 over scenario 1 thinking of less downtime and a smaller number of faults.
But from the calculations performed in case 1 and case 2 it is clearly visible that the other expense incurring in case 2 is much higher than what is incurring in case 1.
So practically one should go ahead with case 1 and not with case 2 just by thinking of lesser downtime and faults.
Condition Monitoring of Assets
Normally fault analysis is done and power outages are figured out when the gap in the power generation or the overall system performance is seen. But this practice can result in severe damage to the equipment or system which can cost heavily to the asset owner be
The best practice is to perform condition monitoring on a regular interval basis to identify changes that could indicate a developing fault. It is a major part of predictive maintenance as implementing condition monitoring allows for maintenance to be scheduled and preventive actions are taken to prevent further failure and subsequent unplanned downtime.
Traditional condition monitoring was mainly based on vibration analysis, but more modern, innovative techniques use sensors to measure different parameters in real-time and can send an alert when a change is detected.
While condition monitoring solutions may require some investment, these expenses are returned by preventing costly unplanned downtimes as a result of machine failure, as well as eliminating the unnecessary maintenance costs associated with scheduling maintenance based on operating hours rather than the actual condition.
When used with connected systems, condition monitoring allows users to make the most of planned maintenance downtime, servicing multiple machines and addressing all problems simultaneously.
Proactive condition monitoring is also important from a safety perspective, as the effective monitoring and maintenance of machinery prevent accidents from occurring.
Advantages of following the corrective measures
- Protect the other connected assets
Failure in a single piece of equipment can cause damage in other connected systems compounding the problem further while also multiplying repair/replacement costs. While in case of condition monitoring as the condition is monitored on a continuous basis you can get forewarned in case of any repair/replacement needed in time to avoid any unexpected failure.
- Avoid unplanned downtime
One needs to manage the performance of the system to fulfill the commitments to the client. But what if you face unplanned downtime due to unexpected failure in the system which ultimately results in delayed operations. As planning is the heart of everything with the condition monitoring you can plan to avoid any additional costs incurred due to any emergency maintenance staff.
- Maximizing ROI
Using condition monitoring as part of a predictive maintenance program can increase the return on investment (ROI) of mechanical assets. Preventive maintenance programs are set at regular intervals or after a set number of operating hours, irrespective of whether the maintenance is required or not. Through condition monitoring, it is possible to eliminate unnecessary maintenance and downtimes by only scheduling repairs when required. This means that you can get more working value from each machine, reducing the total cost of ownership and maximizing the ROI for your equipment.
- Improved Safety
Working in an unsafe environment could pose a threat to employees working nearby. In condition monitoring as the failures are detected before the system breaks safeguards employees’ safety and ensures a safe work environment.
- Efficient Maintenance
You can treat it better when you know where the fault lies. In condition monitoring, fault location is identified which saves time also the cost which is paid to the maintenance engineers.
- Improved asset performance
Condition monitoring can also improve the efficiency of assets. By having a record of which parts are running poorly, you can focus efficiency improvement efforts on those specific parts, thereby improving the overall capabilities of your equipment.