Md. Code Regs. 20.50.09.02 - Definitions

A. In this chapter, the following terms have the meanings indicated.

B. Terms Defined.

(1) "Adverse system impact" means a negative effect, due to technical or operational limits on conductors or equipment being exceeded, that may compromise the safety or reliability of the electric distribution system.

(2) "Affected system" means a utility electric system that is affected by the interconnection of a small generator facility to another utility's electric distribution system.

(3) 'Aggregate generation" means the aggregated net system capacities of all small generator facilities across multiple points of common coupling.

(4) "Applicant" means a person who has submitted an interconnection request to interconnect a small generator facility to a utility's electric distribution system.

(5) "Area network" means a type of electric distribution system served by multiple transformers interconnected in an electrical network circuit, often used in large, densely populated metropolitan areas.

(6) "Certificate of completion" means a certificate provided by a utility to an applicant containing information about the interconnection equipment used, its installation, and local inspections.

(7) "Closed circuit" means an electric distribution system circuit with no available hosting capacity.

(8) "Commissioning test" means one of several tests applied to a small generator facility by the applicant after construction is completed to verify that the small generator facility does not create adverse system impacts, including the test specified in Section 5.4 of IEEE Standard 1547.

(9) "Default utility required inverter settings profile" means a utility set of default smart inverter settings optimized for use across a utility's service territory.

(10) "Distributed energy resource" means any geographically dispersed energy resource located on an electric distribution system that produces electricity or offsets electrical demand including small generator facilities, energy storage devices, energy efficiency devices, and demand response devices.

(11) "Distribution upgrade" means a required addition or modification to the utility electric distribution system, excluding the interconnection facilities, necessary to accommodate the interconnection of a small generator facility.

(12) "Draw-out type circuit breaker" means a molded case switching device that:

(a) Can be inserted into or removed from its enclosure during no-load conditions; and

(b) Is capable of making, carrying, and breaking currents under normal and abnormal circuit conditions.

(13) Electric Distribution System.

(a) "Electric distribution system" means the facilities and equipment used to transmit electricity generally at less than 69 kV to ultimate usage points such as homes and industries from interchanges with higher voltage transmission networks that transport bulk power over longer distances.

(b) "Electric distribution system" has the same meaning as the term Area EPS as defined in Section 3.1.6.1C of IEEE Standard 1547.

(14) "Energy Storage Device" means apiece of equipment that captures energy produced at one time, stores that energy for a period of time, and delivers that energy as electricity at a future time.

(15) "Fault current" means the electrical current that flows through a circuit during an electrical fault condition, such as when one or more electrical conductors contact ground or each other.

(16) "Grid support services" means compensated or uncompensated services unrelated to wholesale markets provided by a small generator facility that support the safety, stability, reliability, or economics of the electric grid.

(17) "Hosting capacity" means the amount of aggregate generation that can be accommodated on an electric distribution system or area, or a system component, without requiring infrastructure upgrades.

(18) "Hosting capacity reporting system" means the information available on a utility website providing reports, tabular data, or maps of hosting capacity available on the electric distribution system.

(19) "Hosting capacity upgrade plan" means a utility plan to promote clean energy interconnection for a particular area or a proposal to open multiple restricted and closed circuits or areas on an electric system in the aggregate through proactive distribution system investments that includes a cost allocation and recovery proposal, under conditions that are approved by the Commission.

(20) "IEEE Standard 1547" means the standard incorporated by reference in COMAR 20.50.02.02C.

(21) "IEEE Standard 1547.1" means the standard incorporated by reference in COMAR 20.50.02.02C.

(22) "Inadvertent export" means the unscheduled export of power from a small generator facility, beyond a specified magnitude and for a limited duration, generally due to fluctuations in load-following behavior.

(23) "Interconnection agreement" means an agreement that contains details regarding the proposed interconnection equipment and its operation to ensure the reliability and safety of the grid, including schedules, rights, obligations, and terms and conditions that become effective on the date the agreement is executed by the utility and the interconnection customer.

(24) "Interconnection customer" means an entity that proposes to interconnect or has interconnected a small generator facility to an electric distribution system.

(25) Interconnection Equipment.

(a) "Interconnection equipment" means a group of components or an integrated system connecting an electric generator with a local electric power system, or an electric distribution system.

(b) "Interconnection equipment" means all interface equipment including switchgear, protective devices, inverters, or other interface devices.

(c) "Interconnection equipment" includes equipment installed as part of an integrated equipment package that includes a generator or other electric source.

(26) Interconnection Facilities.

(a) "Interconnection facilities" means facilities and equipment required by the utility to accommodate the interconnection of a small generator facility.

(b) "Interconnection facilities" includes all facilities and equipment between the small generator facility and the point of interconnection, and modifications, additions, or upgrades that are necessary to physically and electrically interconnect the small generator facility to the electric distribution system.

(c) "Interconnection facilities" includes any distribution upgrade.

(27) "Interconnection facility cost sharing" means the allocation of distribution interconnection facility upgrade costs among multiple small generator facility projects that utilize the hosting capacity created by an interconnection facility upgrade.

(28) "Interconnection request" means an applicant's request for the interconnection of a small generator facility, or to increase the capacity or operating characteristics of a small generator facility that is already interconnected with the utility's electric distribution system.

(29) "Interconnection study" means an interconnection feasibility study, interconnection system impact study, or interconnection facilities study as described in Regulation .12 of this chapter.

(30) "Limited export agreement" means an agreement for energy supplied to the grid by an interconnection customer that may be managed to specified ramp rates and generation levels for operating conditions, as specified in the interconnection agreement or in a separate limited export agreement.

(31) "Line section" means that portion of a utility electric distribution system connected to an interconnection customer, bounded by automatic sectionalizing devices, or the end of the distribution line.

(32) Local Electric Power System.

(a) "Local electric power system" means those facilities that deliver electric power to a load that are contained entirely within a single premises or group of premises.

(b) "Local electric power system" has the same meaning as the term local electric power system as defined in Section 3.1.6.2C of IEEE Standard 1547.

(33) "Meter collar adapter" means an electronic device that is installed between a residential electric meter and the meter socket, for the purpose of facilitating the deployment of customer-owned or customer-leased technology.

(34) "Minor equipment modification" means a change to the proposed small generator facility that does not have a significant impact on safety or reliability of the electric distribution system.

(35) "Minor system modification" means a change to the distribution system:

(a) Located between the service tap on the distribution circuit and the meter serving the applicant; or

(b) That the utility estimates will entail less than 4 hours of work and less than $1,500 in materials.

(36) "Nameplate capacity" means the maximum rated output of a generator, electric power production equipment or energy storage under specific conditions designated by the manufacturer is usually listed on a nameplate physically attached to the equipment.

(37) "Nationally recognized testing laboratory (NRTL)" means a qualified private organization recognized by the Occupational Safety and Health Administration to perform independent safety testing and product certification.

(38) "Net system capacity" means the total export capacity at a point of common coupling of a small generator facility as measured by the nameplate capacities of all power production units and energy storage devices minus their consumption of electrical power, if applicable, as limited through the use of a control system, power relays, or other similar device settings or adjustments.

(39) "Parallel operation" means the sustained state of operation over 100 milliseconds which occurs when a small generator facility is connected electrically to the electric distribution system, and thus has the ability for electricity to flow from the small generator facility to the electric distribution system.

(40) "Permission to operate notice" means the written permission provided by a utility in the form of an email or letter authorizing an interconnection customer to interconnect and operate its small generator interconnection facility.

(41) "Point of common coupling" means the point of interconnection where the small generator facility is electrically connected to the electric distribution system.

(42) "Point of interconnection " has the same meaning as the term "point of common coupling".

(43) "Primary line" means a distribution line rated at greater than 600 volts.

(44) "Primary voltage hosting capacity upgrade cost" means the equipment upgrade costs of all interconnection equipment, interconnection facilities, protective devices and associated communications systems, and other upgrades that directly increase hosting capacity for multiple primary voltage and secondary voltage interconnection customers while excluding equipment upgrade costs that solely benefit a single interconnection customer, to the extent practicable and material.

(45) "Primary voltage interconnection customer" means an interconnection customer with a point of interconnection at greater than 600 nominal volts.

(46) Proposed Use.

(a) "Proposed use" means the operational control modes of a small generator facility upon which the applicant's technical review is based and under which the small generator facility is bound to operate upon the execution of the interconnection agreement.

(b) "Proposed use" for a small generator facility includes a combination of electric generators and energy storage devices operating in specified operational control modes during specified time periods.

(47) "Queue position" means the order of a completed interconnection request, relative to all other pending completed interconnection requests, that is established based upon the date and time of receipt of the completed interconnection request by the utility.

(48) "Radial distribution circuit" means a circuit configuration in which independent feeders branch out radially from a common source of supply.

(49) "Reserve hosting capacity" means the amount of hosting capacity reserved for small generator facilities on an electric distribution system circuit.

(50) "Restricted circuit" means an electric system distribution circuit with reserve hosting capacity.

(51) "Rightsizing" means to increase the size, scope, and cost of an electric utility hosting capacity upgrade project, following a distributed energy resource interconnection request, to account for both the immediate interconnection customer's needs and future hosting capacity needs that are identified by the electric utility through a distributed energy resource forecast.

(52) "Scoping meeting" means a meeting between the applicant and utility conducted for the purpose of discussing alternative interconnection options, exchanging information, including any electric distribution system data and earlier study evaluations that would be reasonably expected to impact interconnection options, analyzing information, and determining the potential feasible points of interconnection.

(53) "Secondary line" means a service line subsequent to the primary line that is rated for 600 volts or less, also referred to as the customer's service line.

(54) "Secondary voltage hosting capacity upgrade cost" means the costs of all primary voltage and secondary voltage interconnection equipment upgrades that directly increase secondary voltage hosting capacity available to multiple secondary voltage interconnection customers while excluding all primary voltage and secondary voltage interconnection equipment upgrade costs that solely benefit a single interconnection customer, to the extent practicable and material.

(55) "Secondary voltage interconnection customer" means an interconnection customer with a point of interconnection at less than or equal to 600 nominal volts.

(56) "Shared transformer" means a transformer that supplies secondary source voltage to more than one customer.

(57) "Site-specific utility required inverter settings profile" means a set of smart inverter settings optimized for use at a specific site on a utility's electric system.

(58) Small Generator Facility.

(a) "Small generator facility" means the equipment used to generate or store electricity that operates in parallel with the electric distribution system.

(b) "Small generator facility" includes an electric generator, a prime mover, energy storage device, and the interconnection equipment required to safely interconnect with the electric distribution system or local electric power system.

(59) "Smart Inverter" means any inverter hardware system certified to be compliant with IEEE 1547-2018 or subsequent revisions to these standards.

(60) Spot Network.

(a) "Spot network" means a type of electric distribution system that uses two or more inter-tied transformers to supply an electrical network circuit.

(b) "Spot network" is generally used to supply power to a single customer or a small group of customers.

(c) "Spot network" has the same meaning as the term is defined in 4.1.4 of IEEE Standard 1547.

(61) "Statewide utility required inverter settings profile" or "grid code" means a set of smart inverter settings optimized for use Statewide that can be used by utilities and manufacturers in establishing defaults.

(62) "Utility monitoring and control plan" means a plan to monitor and control, in the aggregate, a set of small generator facilities in multiple locations that includes a cost recovery method, under conditions that are approved by the Commission.

(63) "Utility required inverter settings profile" means smart inverter settings for a small generator facility that are established by a utility.

(64) "Witness test" means, for lab-certified or field-approved equipment, verification either by an on-site observation or review of documents by the utility that the interconnection installation evaluation required by Section 5.3 of IEEE Standard 1547 and the commissioning test required by Section 5.4 of IEEE Standard 1547 have been adequately performed.

Notes

Md. Code Regs. 20.50.09.02

Regulation .02 amended effective 45:20 Md. R. 920, eff. 10/8/2018; amended effective 47:8 Md. R. 436, eff. 4/20/2020; amended effective 51:24 Md. R. 1082, eff. 12/12/2024.