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
My family’s foundation has installed over 9MW of solar in communities in WI. The cooperative I consult with, Legacy Solar Co-op is also at the forefront of DER development in WI communities. 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. RSD add extra cost to projects and impact system design and location, and these systems are experiencing a tremendous amount of failure with both installers and customers. 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. These devices are not serving the safety code they are meant for. It’s time to update the code and better train utility field staff and first responders how to safety disconnect rooftop PV equipment.
We are a Wisconsin based nonprofit and our mission is to help other Wisconsin nonprofits such as schools, churches, service and community organizations get solar. We want solar to be affordable, safe and easy to install in order to promote as much solar as possible in our state.
Thank you Alliance for understanding reality of PV!
Also, Most AHJ’s (based on their interruptation of NEC intent) forcing ’blanket’s code requirements, to shut down an array on 1/2 of a residential hip roof, is unwarranted (not a safety issue) & just extra cost to homeowner!
Let’s get these changes to allow the customer and contractor to have safe and cost effective systems without enriching the module, optimzer and microinverter manufacturers
Remote module shutdown devices are not necessary at all for fireman safety. The only thing that needs to be done is isolate the array negative terminal and Earth ground.
That way no shock can occur when touching the positive line and the roof structure. Then have a separate conduit for both positive and negative separated by 3 ft. In this way the fireman cannot cut through both of the lines with his chainsaw at the same time so he cannot cause a short. To shut the array down, a simple cut off at the inverter is all that is needed to stop the current flow.
It doesn’t need to be any more complicated than that.
Hope Hodges signed Sign Now
via Ben Zook
2022-08-19 11:03:44 -0500
petition signature
Victoria Lauretta signed Sign Now
via Ben Zook
2022-08-18 20:35:10 -0500
Please make the proper changes
petition signature
Quinn Weber signed Sign Now
2022-08-09 15:43:46 -0500
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Elise Couillard signed Sign Now
2022-08-09 14:25:04 -0500
My family’s foundation has installed over 9MW of solar in communities in WI. The cooperative I consult with, Legacy Solar Co-op is also at the forefront of DER development in WI communities. 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. RSD add extra cost to projects and impact system design and location, and these systems are experiencing a tremendous amount of failure with both installers and customers. 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. These devices are not serving the safety code they are meant for. It’s time to update the code and better train utility field staff and first responders how to safety disconnect rooftop PV equipment.
Elise Couillard
Couillard Solar Foundation and Legacy Solar Co-op
petition signature
Jackie Harrison-Jewell signed Sign Now
2022-08-09 10:39:30 -0500
We are a Wisconsin based nonprofit and our mission is to help other Wisconsin nonprofits such as schools, churches, service and community organizations get solar. We want solar to be affordable, safe and easy to install in order to promote as much solar as possible in our state.
petition signature
Michael Champagne signed Sign Now
2022-08-09 05:29:00 -0500
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Gaylen Atkinson signed Sign Now
2022-08-08 19:56:26 -0500
I am now a retired electrical engineer that during my career I designed and contracted many PV and other solar energy systems
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Jim Tucker signed Sign Now
2022-08-08 18:20:45 -0500
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Cole Van Horn signed Sign Now
2022-08-08 14:33:22 -0500
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Kenny Blemel signed Sign Now
2022-08-08 13:43:33 -0500
Witnessing several recent off grid residential 24 volt fires in New Mexico has shown me the need arc fault detection for energy storage.
petition signature
Sean Griesenbeck signed Sign Now
2022-07-18 19:57:28 -0500
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Charles Ferguson signed Sign Now
2022-07-18 17:19:56 -0500
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Blake Cmajdalka signed Sign Now
2022-07-18 14:39:31 -0500
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beau dingler signed Sign Now
2022-07-11 17:25:37 -0500
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George Andrews signed Sign Now
2022-07-08 13:25:21 -0500
Thank you Alliance for understanding reality of PV!
Also, Most AHJ’s (based on their interruptation of NEC intent) forcing ’blanket’s code requirements, to shut down an array on 1/2 of a residential hip roof, is unwarranted (not a safety issue) & just extra cost to homeowner!
petition signature
Tyler Arana signed Sign Now
2022-07-07 10:01:46 -0500
petition signature
Jonah Whitten signed Sign Now
2022-07-06 21:03:53 -0500
Thanks
petition signature
Jeff Max signed Sign Now
2022-07-06 17:17:22 -0500
petition signature
John Palm signed Sign Now
2022-06-29 22:07:09 -0500
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Mark Connolly signed Sign Now
2022-06-29 19:31:41 -0500
Let’s get these changes to allow the customer and contractor to have safe and cost effective systems without enriching the module, optimzer and microinverter manufacturers
petition signature
Fidel Jimenez signed Sign Now
2022-06-29 11:34:13 -0500
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Robert Shaw signed Sign Now
2022-06-29 10:59:45 -0500
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Daniel Phillips signed Sign Now
2022-06-29 06:05:04 -0500
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Wayne OQuin signed Sign Now
2022-06-28 17:13:30 -0500
Many years of good experiences show no need for the additional regulations.
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Joe Utasi signed Sign Now
2022-06-28 16:07:29 -0500
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Steven Lesak signed Sign Now
2022-06-28 15:01:09 -0500
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Dennis Hawkins signed Sign Now
2022-06-24 09:59:22 -0500
Remote module shutdown devices are not necessary at all for fireman safety. The only thing that needs to be done is isolate the array negative terminal and Earth ground.
That way no shock can occur when touching the positive line and the roof structure. Then have a separate conduit for both positive and negative separated by 3 ft. In this way the fireman cannot cut through both of the lines with his chainsaw at the same time so he cannot cause a short. To shut the array down, a simple cut off at the inverter is all that is needed to stop the current flow.
It doesn’t need to be any more complicated than that.
petition signature
Carsten Donohue Moll signed Sign Now
2022-06-23 14:33:59 -0500
petition signature
Dan Dean signed Sign Now
2022-06-22 16:29:43 -0500
Module Level shutdown is not necessary. String level we have with fuses and breakers.
If technology advances to accommodate module level, let’s do it. It is way too early yo try this.
Thanks!
Dr. Daniel Dean
Design Engineer
Earth Wise Solar Technologies
petition signature
Joseph Thaickal signed Sign Now
2022-06-21 20:08:41 -0500
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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:
Elise Couillard
Couillard Solar Foundation and Legacy Solar Co-op
Also, Most AHJ’s (based on their interruptation of NEC intent) forcing ’blanket’s code requirements, to shut down an array on 1/2 of a residential hip roof, is unwarranted (not a safety issue) & just extra cost to homeowner!
That way no shock can occur when touching the positive line and the roof structure. Then have a separate conduit for both positive and negative separated by 3 ft. In this way the fireman cannot cut through both of the lines with his chainsaw at the same time so he cannot cause a short. To shut the array down, a simple cut off at the inverter is all that is needed to stop the current flow.
It doesn’t need to be any more complicated than that.
If technology advances to accommodate module level, let’s do it. It is way too early yo try this.
Thanks!
Dr. Daniel Dean
Design Engineer
Earth Wise Solar Technologies