With what technical standards should mini-grids comply?

Speeches Shim

Short Answer

International codes and standards govern the design quality, safety and reliability of mini-grid installations. Mini-grid system design and installation should meet applicable international electrical code requirements, such as those established by the International Electrotechnical Commission (IEC) or National Electric Code (NEC). The IEC is the global leader in international specifications for electrical, electronic and related technologies. IEC’s standards serve as the basis for national standards and as references for international contracts.

The NEC was developed in the United States and was intended to provide safety regulations to prevent electrical fires. While NEC guidelines are mandatory across the United States, some other countries like Colombia, Mexico and Venezuela also have adopted the guidelines. Worldwide, however, IEC regulations are more commonly used.

Electrical Design Standards

Safety Standards

Mini-grids should comply with safety standards, even if the standards are more extensive than those for conventional electric power grids. Mini-grids use complex technology that sometimes includes energy storage, and they pose greater hazards. Experienced mini-grid system developers understand these hazards and have developed safety measures to mitigate them. In particular, mini-grids must be able to shut down rapidly and safely in an emergency.

Technology-specific Standards

Certain energy technologies have specific technical standards. For example, mini-grids systems that use photovoltaic (PV) arrays require overcurrent protection to protect conductors and equipment from carrying current beyond what they are designed to take. PV codes are changing quickly and may not be consistent across standards. Common standards for wind energy come from the Small Wind Certification Council (SWCC), which has a rating for small wind generators, and the American Wind Energy Association (AWEA).

A wide range of codes govern other energy sources and generators. Prominent standards organizations include the IEC, NEC, Underwriters Laboratory (UL), National Electrical Manufacturers Association, National Fire Protection Association, Institute of Electrical and Electronics Engineers, American National Standards Institute and International Standards Organization.

Energy Storage Standards

Codes, standards and regulations for energy storage systems are still evolving, and a comprehensive list was developed by the Sandia National Laboratory. Liability issues make storage standards particularly challenging. If improperly designed and used, batteries can overheat and explode, causing damage, leaking chemicals and endangering humans. Not only do legal bodies struggle to adopt uniform regulations for categorizing and assessing fault in these cases, but battery technology is currently changing so rapidly that regulators are unable to keep up with them.

Further Explanation of Key Points

What Does It Mean for a Component to Be “Listed?”

Rated or “listed” mini-grid components are those which have received approval from independent certified laboratories acceptable to the authority with jurisdiction in the area. Two examples listings are the UL listing and the Japan Electrical Safety and Environment Technologies Laboratory (JET) standards. Other common markings, such as the European Conformity marking, indicate that the manufacturer declares the product meets the requirements, but that an outside agency has not verified the claim. Mini-grid systems must use rated components only for their approved uses. For example, a listed direct current (DC) fuse or circuit breaker can only be used for DC wiring, not alternating current (AC).

What Challenges Do Technical Standards Pose?

Establishing standards will not, by itself, ensure technical soundness or safety. Rapidly changing codes and a lack of trained inspectors pose challenges for mini-grid developers and regulators. Few developing countries have enough inspectors to enforce codes, and many of those inspectors lack experience applying codes to renewable energy systems. For rapidly evolving technologies like mini-grids, codes may become outdated after just a few years. Developers, regulators and inspectors should review codes regularly.

Putting it Into Practice

Standards and Listings for Electrical Systems and Components

The list of resources below outlines some of the most widely used standards and listings for different types of mini-grid projects and locations. This list is not exhaustive; developers will need to determine the appropriate standards and listings for their mini-grid locations and technologies. Please note that payment may be required in order to access some of the resources.

Resources

Common Renewable Energy Electrical Product Test Standards

AWEA (2009). AWEA 9.1: Small Wind Turbine Performance and Safety Standard.
This document describes standards for small wind turbines’ performance, safety, and durability.

International Electrotechnical Commission (IEC) (2012, 2013). IEC 61730: Photovoltaic (PV) Module Safety Qualification, Parts 1 & 2, Amended.
This document describes the construction (Part 1) and testing (Part 2) requirements for PV modules for electrical and mechanical safety, including mitigating the risk of electrical shock, fire hazards and personal injury.

IEC (2016). IEC 61215: Terrestrial Photovoltaic (PV) Modules – Design Qualification and Type Approval.
This document provides standard for mini-grid module quality and establishes design and type requirements for terrestrial, flat-plate PV systems. It also includes general requirements, specific requirements for different types of PV technology and quality-testing requirements.

IEC (2004). IEC 61727: Photovoltaic (PV) Systems – Characteristics of the Utility Interface.
This document includes requirements for PV systems interconnecting to a central grid.

IEC (2006–2015). IEC TS 62257: Recommendations for Renewable Energy and Hybrid Systems for Rural Electrification.
This document establishes a methodology for applying standards in setting up, managing and implementing rural, decentralized electricity systems.

IEC (2005–2015). IEC 61400: Wind Turbines.
This document establishes standards for wind turbines, including design, noise, power performance, mechanical loads, sound, power level, tonality values, power quality, testing and certification, lighting protection and communications.

UL (2010). UL 1741: Standard for Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy Resources.
This website shows requirements for inverters, converters, charge controllers and interconnection equipment.

Sandia National Laboratory (2015). Energy Storage System Safety – Codes & Standards Presentation.
This is a compendium of Energy Storage System (ESS) safety standards, including ESS components, installation, commissioning, operations and maintenance, incident preparedness, safety codes and certification programs.

UL (2002). UL 1703: Standard for Flat-Plate Photovoltaic Modules and Panels.
This websit describes requirements for flat-plate PV systems.

Certified Electrical Markings for Listed Products

BSI Group is the UK national standards body that produces technical standards and certification for products and services.

CSA Group is a non-profit standards organization, previously known as the Canadian Standards Association. CSA develops a wide range of standards covering 57 different areas and provides training and advice.

DIN - German Institute for Standardization is the German national standards organization, with about thirty thousand standards across a wide range of technology fields.

Electrical Test Laboratory of Intertek Group is a part of Intertek Group and focuses on electrical product safety testing, electromagnetic compatibility (EMC) testing and benchmark performance testing.

JET is Japan’s testing services body, advancing safety in electrical equipment and facilities.

SWCC is a certification body for wind turbines. SWCC has established a standardized system for reporting wind turbine energy and sound performance in North America.

UL, previously Underwriters Laboratories, drafts safety standards for electrical devices and components and serves as an independent safety science company.