“Landscape with a Farm House and Windmill” (1680) / Jacob Isaaksz van Ruisdael
We have always taken a forward-looking approach to the National Electrical Code (NEC) because there is sufficient supply of NEC instructors and inspectors and not enough subject matter experts driving user-interest ideas into it. Today we approach the parts of the 2023 NEC that cover wiring safety for microgrid systems; a relatively new term of art that appropriates safety and sustainability concepts that have existed in electrotechnology energy systems for decades.
Turn to Part II of Article 705 Interconnected Electric Power Production Sources:
You will notice that microgrid wiring safety is a relatively small part of the much larger Article 705 Content. There were relatively minor changes to the 2017 NEC in Section 705.50 — but a great deal of new content regarding Microgrid Interconnection Devices, load side connections, backfeeding practice and disconnecting means — as can be seen in the transcripts of Code-Making Panel 4 action last cycle:
Keep in mind that the NEC says nothing (or nearly very little, in its purpose stated in Section 90.2) about microgrid economics or the life cycle cost of any other electrical installation. It is the claim about economic advantages of microgrids that drive education facility asset management and energy conservation units to conceive, finance, install, operate and — most of all — tell the world about them.
In previous posts we have done our level best to reduce the expectations of business and finance leaders of dramatic net energy savings with microgrids — especially on campuses with district energy systems. Microgrids do, however, provide a power security advantage during major regional contingencies — but that advantage involves a different set of numbers.
Note also that there is no user-interest from the education facility industry — the largest non-residential building construction market in the the United States — on Panel 4. This is not the fault of the NFPA, as we explain in our ABOUT.
The 2023 NEC was released late last year.
The 2026 revision cycle is in full swing with public comment on the First Draft receivable until August 24, 2024. Let’s start formulating our ideas using the 2023 CMP-4 transcripts. The link below contains a record of work on the 2023 NEC:
We collaborate with the IEEE Education & Healthcare Facility Committee which meets online 4 times per month in European and American time zones. Since a great deal of the technical basis for the NEC originates with the IEEE we will also collaborate with other IEEE professional societies.
Mike Anthony’s father-in-law and son maintaining the electrical interactive system installed in the windmill that provides electricity to drive a pump that keeps the canal water at an appropriate level on the family farm near Leeuwarden, The Netherlands.
Best practice literature to be covered in our 11 AM session today are listed below. These codes and standards ensure safety, reliability, and compliance for underground electrical and telecommunications installations:
Relevance: The NEC, published by the National Fire Protection Association, is the primary standard for safe electrical installations in the U.S. Articles 300 (Wiring Methods), 310 (Conductors for General Wiring), and 230 (Services) cover underground wiring, including burial depths, conduit requirements, and direct-burial cables like Type UF and USE-2. For example, NEC 300.5 specifies minimum cover depths (e.g., 24 inches for direct-burial cables, 18 inches for PVC conduit).
Key Aspects: Rules for conductor protection, grounding, GFCI requirements, and conduit types (e.g., Schedule 80 PVC). Adopted by most U.S. jurisdictions with local amendments.
ANSI/TIA-568 Series (Commercial Building Telecommunications Cabling Standards)
Relevance: Governs low-voltage telecommunications cabling, including underground installations. TIA-568.2-D (Balanced Twisted-Pair) and TIA-568.3-D (Optical Fiber) specify performance requirements for cables like Cat6 and fiber optics, including maximum distances (e.g., 100 meters for twisted-pair).
Key Aspects: Ensures signal integrity, proper separation from high-voltage lines, and compliance for plenum or direct-burial-rated cables. Voluntary unless mandated by local codes.
IEEE 835 (Standard Power Cable Ampacity Tables)
Relevance: Provides ampacity ratings for underground power cables, critical for sizing conductors to prevent overheating.
Key Aspects: Includes data for direct-burial and ducted installations, considering soil thermal resistivity and ambient conditions. Often referenced alongside NEC for high-current applications.
UL 83 (Standard for Thermoplastic-Insulated Wires and Cables)
Relevance: Underwriters Laboratories standard for wires like THWN-2, commonly used in underground conduits. Ensures cables meet safety and performance criteria for wet locations.
Key Aspects: Specifies insulation durability, temperature ratings, and suitability for direct burial or conduit use. NEC requires UL-listed cables for compliance.
OSHA 1910.305 (Wiring Methods, Components, and Equipment)
Relevance: U.S. Occupational Safety and Health Administration standard for workplace electrical safety, including underground installations in industrial settings.
Key Aspects: Specifies approved wiring methods (e.g., armored cable, conduit) and enclosure requirements for underground cable trays or boxes. Focuses on worker safety during installation and maintenance.
CSA C22.1 (Canadian Electrical Code)
Relevance: Canada’s equivalent to the NEC, governing underground electrical installations. Similar to NEC but tailored to Canadian conditions and regulations.
Key Aspects: Defines burial depths, conduit types, and grounding requirements. For example, low-voltage cables (<30V) require 6-inch burial depth, like NEC.
Notes:
Regional Variations: Always consult local building authorities, as codes like the NEC or AS/NZS 3000 may have amendments. For example, some U.S. states reduce burial depths for GFCI-protected circuits (NEC 300.5).
Low-Voltage vs. High-Voltage: Standards like TIA-568 and ISO/IEC 11801 focus on low-voltage (e.g., <50V) telecommunications, while NEC and IEC 60364 cover both power and telecom.
Practical Compliance: Before installation, call 811 (U.S.) or equivalent to locate underground utilities, and obtain permits/inspections as required by local codes.
Critical Examination: While these standards are authoritative, they can lag behind technological advancements (e.g., new cable types like GameChanger exceeding TIA-568 limits). Over-reliance on minimum requirements may limit performance for cutting-edge applications.
The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) is an ANSI-accredited continuous-maintenance standards developer (a major contributor to what we call a regulatory product development “stream”). Continuous maintenance means that changes to titles in its catalog can change in as little as 30-45 days. This is meaningful to jurisdictions that require conformance to the “latest” version of ASHRAE 90.1
Among the leading titles in its catalog is ASHRAE 90.1 Energy Standard for Sites and Buildings Except Low-Rise Residential Buildings. Standard 90.1 has been a benchmark for commercial building energy codes in the United States and a key basis for codes and standards around the world for more than 35 years. Free access to ASHRAE 90.1 version is available at the link below:
Chapter 9: Lighting, begins on Page 148, and therein lie the tables that are the most widely used metrics (lighting power densities) by electrical and illumination engineers for specifying luminaires and getting them wired and controlled “per code”. Many jurisdictions provide access to this Chapter without charge. Respecting ASHRAE’s copyright, we will not do so here but will use them during today’s Illumination Colloquium, 16:00 UTC.
Keep in mind that recently ASHRAE expanded the scope of 90.1 to include energy usage in the spaces between buildings:
Education industry facility managers, energy conservation workgroups, sustainability officers, electric shop foreman, electricians and front-line maintenance professionals who change lighting fixtures, maintain environmental air systems are encouraged to participate directly in the ASHRAE consensus standard development process.
Univerzita Karlova
We also maintain ASHRAE best practice titles as standing items on our Mechanical, Water, Energy and Illumination colloquia. See our CALENDAR for the next online meeting; open to everyone.
Issue: [Various]
Category: Mechanical, Electrical, Energy Conservation, Facility Asset Management, US Department of Energy, #SmartCampus
Colleagues: Mike Anthony, Larry Spielvogel, Richard Robben
N.B. We are knocking on ASHRAE’s door to accept proposals for reducing building interior power chain energy and material waste that we cannot persuade National Electrical Code committee to include in the 2026 revision of the National Electrical Code.
“…The solar panels will populate the gothic chapel roof, producing an approximate 105,000 kWh of energy a year – enough to run the chapel’s electricity, and saving around £20,000 in energy bills per year. The college confirmed that any excess energy would be sold off to the national grid.
Solar panels perform better when listening to music:
A 2013 study by researchers at Imperial College London and Queen Mary University of London showed that solar panels actually work better when exposed to music, of multiple genres. Scientists at the university proved that when exposed to high pitched sounds, like those found in rock and pop music, the solar cells’ power output increased by up to 40 percent. Classical music was also found to increase the solar cells’ energy production, but slightly less so than rock and pop, as it generally plays at a lower pitch than pop and rock. Whether they know it or not, British band Coldplay are just one of the artists benefitting from this research. During their 2021 tour, they installed solar photovoltaic panels in the build-up to each show, “behind the stage, around the stadium and where possible in the outer concourses”…
To determine how much electrical power and lighting 12 kilowatts (kW) will provide for an educational facility, we need to consider the following factors:
Power Distribution: How the 12 kW will be distributed across different electrical needs such as lighting, computers, HVAC (heating, ventilation, and air conditioning), and other equipment.
Lighting Requirements: The specific lighting requirements per square foot or room, which can vary based on the type of facility (classrooms, libraries, laboratories, etc.).
Efficiency of Lighting: The type of lighting used (e.g., LED, fluorescent, incandescent) as this affects the power consumption and lighting output.
We start with lighting.
Lighting Efficiency:
LED lights are highly efficient, typically around 100 lumens per watt.
Fluorescent lights are less efficient, around 60-70 lumens per watt.
Lighting Power Calculation:
12 kW (12,000 watts) of LED lighting at 100 lumens per watt would provide: 12,000 watts×100 lumens/watt=1,200,000 lumens
Illumination Requirements:
Classroom: Approximately 300-500 lux (lumens per square meter).
Library or laboratory: Approximately 500-750 lux.
Area Coverage:
If we target 500 lux (which is 500 lumens per square meter), we can calculate the area covered by the lighting: (1,200,000 lumens)/ 500 lux=2,400 square meters
Now we need to allocate power to other loads.
Lighting: Assuming 50% of the 12 kW goes to lighting:
Lighting Power: 6 kW (6,000 watts)
Using the previous calculation: 6,000 watts×100 lumens/watt=600,000 lumens
Area Coverage for lighting (at 500 lux): (600,000 lumens)/500 lux=1,200 square meters
Other Electrical Needs:
Computers and equipment: Typically, a computer lab might use around 100 watts per computer.
HVAC: This can vary widely, but let’s assume 4 kW is allocated for HVAC and other systems.
Breakdown:
Lighting: 6 kW
Computers/Equipment: 2 kW (e.g., 20 computers at 100 watts each)
HVAC and other systems: 4 kW
Summary
Lighting: 12 kW can provide efficient LED lighting for approximately 1,200 square meters at 500 lux.
General Use: When distributed, 12 kW can cover lighting, a computer lab with 20 computers, and basic HVAC needs for a small to medium-sized educational facility.
The exact capacity will vary based on specific facility needs and equipment efficiency.
Should every campus building generate its own power? Sustainability workgroups are vulnerable to speculative hype about net-zero buildings and microgrids. We remind sustainability trendsniffers that the central feature of a distributed energy resource–the eyesore known as the university steam plant–delivers most of the economic benefit of a microgrid. [Comments on Second Draft due April 29th] #StandardsMassachusetts
“M. van Marum. Tweede vervolg der proefneemingen gedaan met Teyler’s electrizeer-machine, 1795” | An early energy storage device | Massachusetts Institute of Technology Libraries
We have been following the developmental trajectory of a new NFPA regulatory product — NFPA 855 Standard for the Installation of Stationary Energy Storage Systems — a document with ambitions to formalize the fire safety landscape of the central feature of campus microgrids by setting criteria for minimizing the hazards associated with energy storage systems.
The fire safety of electric vehicles and the companion storage units for solar and wind power systems has been elevated in recent years with incidents with high public visibility. The education industry needs to contribute ideas and data to what we call the emergent #SmartCampus;an electrotechnical transformation — both as a provider of new knowledge and as a user of the new knowledge.
Transcripts of technical deliberation are linked below:
Comment on the 2026 revision received by March 27, 2025 will be heard at the NFPA June 2025 Expo through NFPA’s NITMAM process.
University of Michigan | Average daily electrical load across all Ann Arbor campuses is on the order of 100 megawatts
A fair question to ask: “How is NFPA 855 going to establish the standard of care any better than the standard of care discovered and promulgated in the NFPA 70-series and the often-paired documents NFPA 110 and NFPA 111?” (As you read the transcript of the proceedings you can see the committee tip-toeing around prospective overlaps and conflicts; never a first choice).
Suffice to say, the NFPA Standards Council has due process requirements for new committee projects and, obviously, that criteria has been met. Market demand presents an opportunity to assemble a new committee with fresh, with new voices funded by a fresh set of stakeholders who, because they are more accustomed to advocacy in open-source and consortia standards development platforms, might have not been involved in the more rigorous standards development processes of ANSI accredited standards developing organizations — specifically the NFPA, whose members are usually found at the top of organization charts in state and local jurisdictions. For example we find UBER — the ride sharing company — on the technical committee. We find another voice from Tesla Motors. These companies are centered in an industry that does not have the tradition of leading practice discovery and promulgation that the building industry has had for the better part of two hundred years.
Our interest in this standard lies on both sides of the education industry — i.e. the academic research side and the business side. For all practical purposes, the most credible, multi-dimensional and effective voice for lowering #TotalCostofOwnership for the emergent smart campus is found in the tenure of Standards Michigan and its collaboration with IEEE Education & Healthcare Facilities Committee (E&H). You may join us sorting through the technical, economic and legal particulars and day at 11 AM Eastern time. The IEEE E&H Committee meets online every other Tuesday in European and American time zones; the next meeting on March 26th. All meetings are open to the public.
University of California San Diego Microgrid
You are encouraged to communicate directly with Brian O’Connor, the NFPA Staff Liaison for specific questions. We have some of the answers but Brian is likely to have all of them. CLICK HERE for the NFPA Directory. Additionally, NFPA will be hosting its Annual Conference & Expo, June 17-20 in San Antonio, Texas; usually an auspicious time for meeting NFPA staff working on this, and other projects.
The prospect of installing of energy storage technologies at every campus building — or groups of buildings, or in regions — is clearly transformational if the education facilities industry somehow manages to find a way to drive the cost of operating and maintaining many energy storage technologies lower than the cost of operating and maintaining a single campus distributed energy resource. The education facility industry will have to train a new cadre of microgrid technology specialists who must be comfortable working at ampere and voltage ranges on both sides of the decimal point that separates power engineers from control engineers. And, of course, dynamic utility pricing (set by state regulatory agencies) will continue to be the most significant independent control variable.
Finding a way to make all this hang together is the legitimate work of the academic research side of the university. We find that sustainability workgroups (and elected governing bodies) in the education industry are vulnerable to out-sized claims about microgrids and distributed energy resources; both trendy terms of art for the electrotechnical transformation we call the emergent #SmartCampus.
We remind sustainability trendsniffers that the central feature of a distributed energy resource — the eyesore known as the university steam plant — bears most of the characteristics of a microgrid. In the videoclip linked below a respected voice from Ohio State University provides enlightenment on this point; even as he contributes to the discovery stream with a study unit.
Ohio State University McCracken Power Plant
Issue: [16-131]
Category: District Energy, Electrical, Energy, Facility Asset Management, Fire Safety, Risk Management, #SmartCampus, US Department of Energy
Colleagues: Mike Anthony, Bill Cantor (wcantor@ieee.org). Mahesh Illindala
Artificial lighting was first introduced to theater dramatic performance stages in the 17th century. The use of candles and oil lamps initially provided a means to illuminate the stage, allowing performances to take place in the evening and enhancing the visibility for both actors and the audience. Before this development, theatrical performances were typically held during daylight hours due to the reliance on natural light.
In the early 17th century, theaters in England began experimenting with various lighting techniques. Thomas Killigrew’s Theatre Royal, Drury Lane, in London, is often credited as one of the first theaters to use artificial lighting. The use of candles and later oil lamps evolved over time, leading to more sophisticated lighting setups as technology advanced.
The 18th and 19th centuries saw further innovations in stage lighting, including the use of gas lamps. Eventually, the introduction of electric lighting in the late 19th and early 20th centuries revolutionized stage lighting, providing theaters with a more reliable and controllable source of illumination. This allowed for greater creativity in the design and execution of lighting effects, contributing significantly to the overall theatrical experience.
The 2020 National Electrical Code (NEC) contains significant revisions to Article 625 Electric Vehicle Power Transfer Systems. Free access to this information is linked below:
Mighty spirited debate. Wireless charging from in-ground facilities employing magnetic resonance are noteworthy. Other Relevant Articles:
Article 240: Overcurrent Protection: This article includes requirements for overcurrent protection devices that could be relevant for EV charging systems.
Article 210: Branch Circuits: General requirements for branch circuits, which can include circuits dedicated to EVSE.
Article 220: Load Calculations: Guidelines for calculating the electrical load for EVSE installations.
Article 230: Services: General requirements for electrical service installations, which can be relevant for EVSE.
Article 250: Grounding and Bonding: Requirements for grounding and bonding, which are critical for safety in EVSE installations.
Technical committees meet November – January to respond. In the intervening time it is helpful break down the ideas that were in play last cycle. The links below provide the access point:
We find a fair amount of administrative and harmonization action; fairly common in any revision cycle. We have taken an interest in a few specific concepts that track in academic research construction industry literature:
Correlation with Underwriters Laboratory product standards
Bi-Directional Charging & Demand Response
Connection to interactive power sources
As a wiring safety installation code — with a large installer and inspection constituency — the NEC is usually the starting point for designing the power chain to electric vehicles. There is close coupling between the NEC and product conformance organizations identified by NIST as Nationally Recognized Testing Laboratories; the subject of a separate post.
Edison electric vehicle | National Park Service, US Department of the Interior
After the First Draft is released June 28th public comment is receivable until August 19th.
We typically do not duplicate the work of the 10’s of thousands of National Electrical Code instructors who will be fanning out across the nation to host training sessions for electrical professionals whose license requires mandatory continuing education. That space has been a crowded space for decades. Instead we co-host “transcript reading” sessions with the IEEE Education & Healthcare Facilities Committee to sort through specifics of the 2020 NEC and to develop some of the ideas that ran through 2020 proposals but did not make it to final ballot and which we are likely to see on the docket of the 2023 NEC revision. That committee meets online 4 times monthly. We also include Article 625 on the standing agenda of our Mobility colloquium; open to everyone. See our CALENDAR for the next online meeting
Issue: [16-102]
Category: Electrical, Transportation & Parking, Energy
Technical Committee 82 of the International Electrotechnical Commission is charged with preparing international standards for the full length of the solar energy power chain The span of the power chain includes the light input, the cell itself, and the fittings and accessories to the end use (utilization) equipment.
The USNA/IEC and participates in its standards development processes; typically collaborating with global research and application engineers in the IEEE Industrial Applications Society and the IEEE Power and Energy Society. To advance its agenda for lower #TotalCostofOwnership for US real asset executives and facility managers Standards Michigan also collaborates closely with subject matter experts who contribute to, and draw from, the knowledge base in the IEEE Education and Healthcare Facilities Committee (E&H).
The IEC permits public commenting on its draft standards; though you will need to establish login credentials:
Your comments will be reviewed by the IEC National Committee of the country you live in, which can decide to propose them as national input for the final draft of the IEC International Standard. This approach makes it easier for individual nations to participate in IEC standards development processes because the resources that national standards bodies need to administer participation resides in Geneva and is managed there.
“The Eclipse of the Sun in Venice, July 6, 1842” | Ippolito Caffi
We collaborate with the IEEE Education & Healthcare Facilities Committee which has its own platform to tracking commenting opportunities:
As of this posting, no interoperability redlines have been released for public consultation. In large measure, IEC titles contribute to a level playing field among multi-national electrical equipment manufacturers so we should not be surprised that there are no redlines to review. When they are released we place them on the agenda of the IEEE E&H Committee which meets 4 times monthly in European and American time zones.
Contact: Mike Anthony, Jim Harvey, Peter Sutherland
LEARN MORE:
[1] US Commenters must route their comments through the USNA/IEC.
[2] Many product and installation standards are developed by the Association of Electrical Equipment and Medical Imaging Manufacturers (NEMA): CLICK HERE
New update alert! The 2022 update to the Trademark Assignment Dataset is now available online. Find 1.29 million trademark assignments, involving 2.28 million unique trademark properties issued by the USPTO between March 1952 and January 2023: https://t.co/njrDAbSpwBpic.twitter.com/GkAXrHoQ9T
