Solar is the future and green, distributed energy supply is the way to go. PV solar systems are a very safe technology and for many years they've been built without any major safety issues.
However, the adoption of Module Level Shutdown (MLSD) in the National Electrical Code (NEC) has caused some unintended consequences. Because proper MLSD solutions are not available today, systems actually became more complex, less safe, and less reliable.
This puts a tremendous burden on solar installers and system buyers – and at the end, only helps utilities and non-renewable energy suppliers.
Let's fix Module Level Shutdown and do it the right way, so that solar can prosper!
The National Electrical Code requires shutdown devices to be added to virtually every single module. Such additional components at the module level would usually not be necessary for operating a solar system properly. However, solar installers are now forced to using technologies that have major downsides and unintended consequences:
Added Cost and Complexity
Shutdown devices must be added to every single module in a PV system. This increases complexity and cost of systems, as more hardware and more labor is required. On top of that, a duopoly controls 90% of the market for shutdown solutions, limiting customer choice and competition.
Having to add a shutdown device to every single module increases the workers time spent on the roof significantly, which adds to the risks of falling, slipping, or tripping.
Current solutions for Module Level Shutdown (MLSD) compromise the reliability of systems, because a vast number of sensitive electronics is placed in the harsh environment of a roof. Each of these components has a failure rate and wear rate over the 20+ years of a system's lifetime. This can turn into a big liability for solar installers and cause distrust in our industry.
A majority of systems with shutdown solutions based on DC optimizers and microinverters (90% of residential installations) produces less energy than systems without these module level power electronics.
Recent articles in mainstream media, such as CNBC or Business Insider, regarding solar fires with DC connector issues shine a bad light on the solar industry. They make look solar unsafe or not trustworthy. Ignoring this issue would be bad for the industry, becasue solar is generally a very safe technology!
Let’s fix Module Level Shutdown (MLSD) and promote innovative solutions that eliminate these problems and help grow distributed solar as an energy source. Such solutions are chip-based, module integrated, and based an open industry standard (SunSpec) - allowing for simplicity, standardized safety, reliability, and customer choice.
To prevent the unintended consequences of the current code requirements and to allow for systems that are simple, safe, and more reliable, we request that code makers make the following changes to the National Electric Code:
Request 1: Revert NEC 2020 690.12 (Module Level Shutdown) to NEC 2014 690.12 (Array Level Shutdown) requirements until proper solutions are available on the market, such as module-integrated, chip-based devices with an open industry standard
Request 2: Revert to NEC 2014 690.12 but keep the 1' array boundary
Request 3: Implementing a maximum electrical noise level requirement for rapid shutdown devices in 690.12
Request 4: Require 690.11 (Arc Fault Circuit Protection) to apply to all solar PV DC circuits, not just those above 80V, to detect any potential fire safety issues
I am in favor of safety and reliability. The current solutions for MLSD offer too little for the added cost and long-term solution. Early products literally had to be removed from the installation due to failure, which doubled installation costs. Recent products are more streamlined, but I still question the long-term reliability exposing electronics to seasonal 100°F temperature swings on rooftop installations in our climate. We need a solution, but since the NEC 2014 cycle, the industry has been forced down a path that favors microinverters over string inverters that narrows options and does not serve our industry nor customers well.
We make a solar roofing product and MLSD is a real headache even if done at the string level. Lot’s of instalation issues, call backs etc…. Big issue in the industry which is not requires in many other countries.
Agree fully with the negative issues of having only two manufacturers with technology that meets NEC module level shutdown standards. It adds cost and increases unreliability. It also prevents other better solutions from being implemented.
MLSD was a solution looking for a problem, the rest of the world has not required MLSD nor does the USA require it. We need reliable low cost systems, MLSD takes away from these important values and adds no measurable advantage.
Having joined the solar industry in 2014, I’ve watched the suspicious rise of MLP requirements give undo advantage to particular companies without consideration of long term quality, cost and safety issues.
Rapid Shutdown devices are giving the industry a bad name for all the downtime they are causing. Many installers are dealing with failures every week and some are dealing with them on a daily basis.
I have invested in over 1 megawatts of arrays myself. All arrays installed before the 2017 NEC code was adapted in our state, Wisconsin, are working fine. Many arrays installed after the code change was made, 2019, have issues shutting down falsely due to the rapid shutdown devices. Rapid shutdown devices are a serious issue when it comes to system failure and are putting Distributed Energy Resources in a very difficult position due to extra cost and the system failure that a majority of installers and customers are experiencing. Utilities do not have to incur this extra cost and the failures that are associated with it. Rapid Shutdown devices are giving the industry a bad name for all the failure they are causing. I know many installers that are dealing with failures every week and some are dealing with them on a daily basis. I have renamed these devices. They are now Rampant Shutdown Devices. You never know when they will shut you down, but they will shut you down.
YES, please fix this problem with module level shutdown. One site we installed solar on had all the optimzers melt or burned up. This is not making anything better.
Our experience with MLPE has been horrible. Only one company makes products specifically designed for their inverter and the reliability is horrible. Other companies products don’t consistently work with other companies products, despite the supposed SunSpec compatibility. Clearly this NEC requirement was way too premature for the market to respond.
My husband and father-in-law worked for years to make energy efficient homes more affordable for everyone. This is another step in the process!
Recent Activity
petition signature
Alli Krug signed Sign Now
2021-02-21 14:09:43 -0600
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Donald Long signed Sign Now
2021-02-21 10:39:21 -0600
Energy is required for modern life, Someone needs to be held responsible for the loss of life.
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Cathy Sims signed Sign Now
2021-02-20 14:39:30 -0600
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Justin Contreras signed Sign Now
2021-02-20 14:38:22 -0600
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Ethan Sims signed Sign Now
2021-02-20 14:37:14 -0600
Lets fix solar
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Sabrina Sims signed Sign Now
2021-02-20 14:35:22 -0600
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Michael Shonka signed Sign Now
2021-02-19 16:23:40 -0600
I am in favor of safety and reliability. The current solutions for MLSD offer too little for the added cost and long-term solution. Early products literally had to be removed from the installation due to failure, which doubled installation costs. Recent products are more streamlined, but I still question the long-term reliability exposing electronics to seasonal 100°F temperature swings on rooftop installations in our climate. We need a solution, but since the NEC 2014 cycle, the industry has been forced down a path that favors microinverters over string inverters that narrows options and does not serve our industry nor customers well.
petition signature
Ariel Anoceto signed Sign Now
2021-02-19 11:14:19 -0600
petition signature
Jorge de la Morena signed Sign Now
2021-02-19 11:05:49 -0600
petition signature
Oliver Koehler signed Sign Now
2021-02-19 08:41:09 -0600
We make a solar roofing product and MLSD is a real headache even if done at the string level. Lot’s of instalation issues, call backs etc…. Big issue in the industry which is not requires in many other countries.
petition signature
John Vandervoort signed Sign Now
2021-02-18 20:49:36 -0600
petition signature
Joel Helleso signed Sign Now
2021-02-18 19:01:44 -0600
This change should be permanent, not temporary.
petition signature
Paul Ahern signed Sign Now
2021-02-18 18:03:28 -0600
Yes, this needs to be fixed
petition signature
Keith Stone signed Sign Now
2021-02-18 17:48:10 -0600
Long overdue.
petition signature
Michael Bennett signed Sign Now
2021-02-18 16:16:32 -0600
Agree fully with the negative issues of having only two manufacturers with technology that meets NEC module level shutdown standards. It adds cost and increases unreliability. It also prevents other better solutions from being implemented.
petition signature
Bobby Price signed Sign Now
2021-02-18 14:09:54 -0600
petition signature
randy dunton signed Sign Now
2021-02-18 14:02:27 -0600
MLSD was a solution looking for a problem, the rest of the world has not required MLSD nor does the USA require it. We need reliable low cost systems, MLSD takes away from these important values and adds no measurable advantage.
petition signature
Ian McCluskey signed Sign Now
2021-02-18 13:41:22 -0600
Having joined the solar industry in 2014, I’ve watched the suspicious rise of MLP requirements give undo advantage to particular companies without consideration of long term quality, cost and safety issues.
petition signature
Raven Stevenson signed Sign Now
via John Kivlin
2021-02-18 06:13:11 -0600
Rapid Shutdown devices are giving the industry a bad name for all the downtime they are causing. Many installers are dealing with failures every week and some are dealing with them on a daily basis.
petition signature
Keith Kahlow signed Sign Now
via John Kivlin
2021-02-17 19:39:40 -0600
Not enough reliable products we try to do more ground mounted solar to avoid RSD and reluctantly moved to AC micro inverters for roof mounted solar.
petition signature
Cal couillard signed Sign Now
via John Kivlin
2021-02-17 13:02:37 -0600
I have invested in over 1 megawatts of arrays myself. All arrays installed before the 2017 NEC code was adapted in our state, Wisconsin, are working fine. Many arrays installed after the code change was made, 2019, have issues shutting down falsely due to the rapid shutdown devices. Rapid shutdown devices are a serious issue when it comes to system failure and are putting Distributed Energy Resources in a very difficult position due to extra cost and the system failure that a majority of installers and customers are experiencing. Utilities do not have to incur this extra cost and the failures that are associated with it. Rapid Shutdown devices are giving the industry a bad name for all the failure they are causing. I know many installers that are dealing with failures every week and some are dealing with them on a daily basis. I have renamed these devices. They are now Rampant Shutdown Devices. You never know when they will shut you down, but they will shut you down.
Cal Couillard
The Couillard Solar Foundation and SpeedSolar
petition signature
James Kerbel signed Sign Now
via John Kivlin
2021-02-17 12:45:58 -0600
YES, please fix this problem with module level shutdown. One site we installed solar on had all the optimzers melt or burned up. This is not making anything better.
petition signature
Kristopher Schmid signed Sign Now
via John Kivlin
2021-02-17 12:42:14 -0600
petition signature
Burke O'Neal signed Sign Now
via John Kivlin
2021-02-17 12:37:07 -0600
Our experience with MLPE has been horrible. Only one company makes products specifically designed for their inverter and the reliability is horrible. Other companies products don’t consistently work with other companies products, despite the supposed SunSpec compatibility. Clearly this NEC requirement was way too premature for the market to respond.
petition signature
Trevor Sumner signed Sign Now
via John Kivlin
2021-02-17 12:20:41 -0600
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Randal Morris signed Sign Now
via Clayton Hanks
2021-02-15 22:13:57 -0600
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Kathy Verduin signed Sign Now
via Clayton Hanks
2021-02-15 21:36:04 -0600
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Jaime Peralta signed Sign Now
via Clayton Hanks
2021-02-15 18:30:41 -0600
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Denise Romano signed Sign Now
via Clayton Hanks
2021-02-15 17:28:43 -0600
petition signature
Brittany Menzel signed Sign Now
via Clayton Hanks
2021-02-15 16:04:08 -0600
My husband and father-in-law worked for years to make energy efficient homes more affordable for everyone. This is another step in the process!
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Module Level Shutdown in the National Electric Code has made #solar systems more complex, less safe, and less reliable. Let's #FixMLSD and do it the right way. Sign the petition:
Make Solar Simple, Safe, and More Reliable
Module Level Shutdown in the National Electric Code has made #solar systems more complex, less safe, and less reliable. Let's #FixMLSD and do it the right way. Sign the petition:
Cal Couillard
The Couillard Solar Foundation and SpeedSolar