Maximizing the Potential of Your Solar PV Assets
InSolPark is committed to optimizing your Solar PV assets for maximum generation efficiency and superior long term return on your solar investment.
With Solar Plants, It’s Not that Simple
“Set it and forget it”
This phrase was made popular by Ron Popeil in his counter-top oven infomercials. It’s a great selling point for a kitchen appliance.
Unfortunately, too many solar plants are operated in this very same way.
This approach has largely been dictated by the current state of solar technology.
In a world of “big data” and “intelligent” everything, solar plants have largely been left behind.
The truth is, solar plant stakeholders have very little visibility into the operational performance of their solar plants. For all of their sophistication, and for all of the hope that they build for a sustainable future, solar plants are still pretty “dumb” by today’s standards.
Times are starting to change, and there are more offerings in the market that provide some level of operational visibility into a solar plants operations. But, for the most part, this visibility is at the string or inverter level of granularity.
While better than no information, string level visibility does not provide the necessary depth of information into the performance of the solar modules themselves.
And visibility, in and of itself, does nothing to correct power degradation caused by solar module mismatch – a common and pervasive condition resulting from normal module aging, cloud cover, uneven soiling, and a host of other factors.
What if you could have both real time module level visibility and a system that corrects for mismatch situations?
The answer is you can!
Since 2007, an innovative new “impedence matching” technology has been installed on solar plants around the world – improving their power production performance from 3% to 25% or more.
This technology also provides the visibility you need – in real time, at the module level, and on the device of your choice.
Not only does it correct for common and highly variable mismatch situations, it can easily identify technical failures such as broken modules, disconnects, varmint damage (e.g. chewed wires), or any other type of breakdown.
If a module is not working in whole or in part, you’ll know – Immediately!
Mean time to respond (MTTR) to these failures can now be measured in hours and days instead of weeks or even months.
And when you make the informed decision “roll a truck”, the maintenance crews can be sent directly to the modules or strings that need attention.
With this planned O&M methodology, you can save upwards of 15% on maintenance costs, in addition to the potentially significant gains in energy production and overall financial performance.
Think of it in this way – one catastrophic failure that remains undetected for any length of time can potentially erase all the realized returns from the plant for the entire year.
When you plunk down $30 bucks for a toaster oven, it’s a great feature to be able to “set it and forget it”.
For a multimillion dollar solar investment, it’s probably not such a good idea.
Visit our website (www.insolpark.com) to learn how you can implement a strategic asset management plan and increase your ROI as a result of continuous peak plant performance.
1. Even Perfectly Architected Systems Under-perform
Your operational Solar Plant may have been designed and built by the best in the business, but even perfectly architected systems under-perform.
Why? Here is one reason.
Solar modules experience production decline as a result of the normal aging process. This is even reflected in solar panel warranties.
Shockingly, in a study on solar module performance degradation conducted at Arizona State University on 1900 solar modules from 8 different manufacturers,~86% of these modules did not meet the 20% degradation over 20 years (20/20) warranty requirements. What hurts a solar plant is the variable nature of this degradation.
The variability of degradation rates leads to increased mismatch.
What is mismatch?
Mismatch occurs when individual solar modules perform differently, or experience different operating conditions than surrounding panels. Mismatch is one of the major contributors to solar plant under-performance.
With degradation rates documented as ranging from .6% to 2.5%, it is easy to see why severe mismatch and the resulting under-performance occur.
It may be the case that panels manufactured more recently will perform better (i.e. degrade less), but the issue becomes will they perform identically better. Remember, it is the variability that hurts.
2. One Bad Apple (i.e. Solar Panel) Can Spoil the Whole “Bunch”!
Why is mismatch so bad for solar plant operations?
Most solar plants are designed and built with strings of individual solar modules connected in serial fashion (“in series”).
When mismatch occurs, it is generally not limited to one module alone. The total current of a string is equal to or lower than the lowest current producing module of that particular string.
When one module in a string is under-performing (e.g. it is shaded), it can drag down the production of the rest of the modules connected in that string even though they may be operating perfectly.
To illustrate how bad this can get, shading that covers 5% of the total area of an array can lead to a 20% loss in energy production of the entire plant.
And in the same ASU study mentioned above, real world results show that mismatch power losses at the string level ranged from around 15% to 26% with a weighted average of about 22%. (Graphic created using data from the ASU Study)
Can you afford this loss in production?
3. Solar Plant Under-performance Can Be Cost-effectively Mitigated
One of the most difficult parts of correcting an under-performing solar plant has been discovering what exactly needs to be done.
Even with readily available monitoring systems, sending out O&M teams (i.e. “rolling a truck”) to manually check each panel, string, connection, bypass diode, and inverter is not only costly, it’s an overall inefficient process.
Fortunately, there are capable retrofit solutions in the market. But most of them still fall short of a truly viable fix for an existing solar plant.
In the end it generally boils down to financial considerations.
If starting from scratch (e.g. building a new plant), many of these optimization offerings can make sense depending on the individual circumstances.
But if the fix is a retrofit, and it requires that you have to make wholesale changes to existing equipment or potentially even go through a moderate system re-design, then the decision to do so becomes harder.
Some other drawbacks of these solutions include:
Cost effective solutions are available. But you need to do your homework when assessing the type of solution you should use to optimize your existing solar plant.
 Investigation of 1,900 Individual Field Aged Photovoltaic Modules for Potential Induced Degradation (PID) in a Positive Biased Power Plant; Jaspreet Singh; November 2011
 Source: PHOTON International Study and Tigo Energy, Inc.