Download Grid Requirements - Bahamas Electricity

Bahamas Power &
Light
REQUIREMENTS FOR GRID INTERCONNECTION OF SMALL SCALE RENEWABLE ENERGY
GENERATION SYSTEMS
1.
PURPOSE
This document describes the general provisions and technical requirements for
connec7ng Small Scale Renewable Genera7on ("SSRG") systems up to the kW specified
below for the various Islands, to BPL's electric distribu7on system ("BPL's Grid").
These requirements:
I.
ensure the compa7bility of the SSRG system with BPL's Grid;
II. ensure the safety of the SSRG system opera7ng in parallel with BPL's Grid;
III. facilitate the safety of BPL's employees, agents, customers and the general
public; and
IV. maintain a high standard of power quality.
2.
CONDITIONS OF SUPPLY
2.1.
New Providence
I.
New Providence based residen7al Small Scale Renewable Genera7on
(“SSRG”) systems shall not supply greater than 5 kilowaRs (kW) to the grid.
II.
New Providence based SSRG systems operated by Small Commercial
customers shall not supply greater than BPL’s es7mate of the customer’s
1
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
average peak demand or 50 kW, whichever is the lesser, to the grid unless
otherwise approved by BPL.
III.
This program is available on a “first come first serve” basis up to a maximum
total of 10,000 kW of installed SSRG capacity on New Providence.
2.2.
Abaco, Eleuthera and Exuma
I.
Abaco, Eleuthera and Exuma based residen7al SSRG systems shall not supply
greater than 3 kW to the grid.
II.
Abaco, Eleuthera and Exuma based SSRG systems operated by Small
Commercial customers shall not supply greater than BPL’s es7mate of the
customer’s average peak demand or 25 kW, whichever is the lesser, to the
grid unless otherwise approved by BPL.
III.
This program is available on a “first come first serve” basis up to a maximum
installed capacity of 500 kW, on each of Abaco, Eleuthera and Exuma.
2.3.
Long Island, Bimini, San Salvador,[ North/Central/South ]Andros, Inagua, Cat Island,
Great Harbour Cay, Black Point and Staniel Cay (Exuma)
I.
Long Island, Bimini, San Salvador, North/Central/South Andros, Inagua, Cat
Island, Great Harbour Cay, Black Point and Staniel Cay (Exuma) based
residen7al SSRG systems shall not supply greater than 2 kW to the grid.
II.
SSRG systems operated by Small Commercial customers in these islands shall
not supply greater than BPL’s es7mate of the customer’s average peak
demand or 15 kW, whichever is the lesser, to the grid unless otherwise
approved by BPL.
2
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
III.
This program is available on a “first come first serve” basis up to a maximum
installed capacity of 250 kW, on each island and Cay named above.
2.4.
All other Family Islands
I.
All other Family Island based residen7al SSRG systems shall not supply greater
than 1 kW to the grid.
II.
SSRG systems operated by Small Commercial customers on these islands shall
not supply greater than BPL’s es7mate of the customer’s average peak
demand or 5 kW, whichever is the lesser, to the grid unless otherwise
approved by BPL.
III.
This program is available on a “first come first serve” basis up to a maximum
installed capacity of 25 kW, per island.
2.5.
The following Table sets out a summary of the capacity limita7ons implemented under
this document.
Residen7al
Max.
System
Avg Peak +
Commercial*
Max. System
Avg Peak +
Max
Installa7on
Size
New Providence & Paradise Island
5kW
50kW
100kW
Abaco, Eleuthera and Exuma
3kW
25kW
50 kW
Long Island, Bimini, San Salvador,
[ North/Central/South ]Andros,
Inagua, Cat Island, Great Harbour Cay,
Black Point and Staniel Cay (Exuma)
2kW
15kW
30kW
All other Family Islands
1kW
5kW
10kW
3
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
3.
SUMMARY OF APPLICATION AND INTERCONNECTION PROCESS
3.1.
Residen7al customers desirous of installing SSRG systems should contact BPL in order
to obtain informa7on on requirements for interconnec7on BEFORE acquiring the SSRG
system. BPL is not obligated to approve or allow the connec7on to the grid of any
installa7on that it considers, non-compliant, unsafe or unfit for purpose.
3.2.
Residen7al customers may obtain applica7on forms, SSRG Interconnec7on Agreements,
and informa7on on SSRG requirements from BPL’s offices.
This informa7on is also
available on BPL's website at www.bahamaselectricity.com.
3.3.
Small Commercial customers may obtain informa7on about the applica7on process,
and the relevant applica7on forms, from offices of the U7li7es Regula7on and
Compe77on Authority (URCA), or from URCA’s website, on or aier 28 February 2017.
3.4.
In order for an interconnec7on to BPL's Grid to be approved, the customer is required
to do the following:
1)
If for an exis7ng system, obtain and complete a SSRG Registra7on Form. This
document should be completed for all systems (on or off grid).
2)
Obtain and review copies of the Requirements for Grid Interconnec7on and
SSRG Interconnec7on Agreement documents before star7ng the project;
3)
Ensure a visible lockable AC disconnect is in an accessible loca7on at or near
BPL's meter and required signage and no7ces are posted.
4
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4)
Complete and submit a SSRG Applica7on Form to BPL, inclusive of all required
suppor7ng documenta7on, so as obtain approval to acquire the desired system.
5)
Once wriRen approval for the acquisi7on of the system is provided, submit all
necessary building and electrical permit applica7ons to the Ministry of Works
with respect to the internal and external wiring, addi7ons, modifica7ons , or
installa7ons done or to be done to facilitate the installa7on of the RGS system,
aRaching a copies of the wriRen approval from BPL;
6)
The installa7on must pass all necessary inspec7ons required by the Ministry of
Works and BPL.
7)
Once all approvals have been obtained and inspec7ons passed, the customer is
required to execute a SSRG Interconnec7on Agreement with BPL to authorize the
connec7on with the grid and provide for the export of energy to the grid under
the terms defined and complete the SSRG Registra7on Form.
For non-grid
connected only the comple7on and submission of the SSRG Registra7on Form is
required.
4.
GENERAL CONDITIONS
Persons desirous of acquiring and connec7ng SSRG systems to BPL's Grid must be
customers in good standing of BPL and the power source must be located at the
customer's owned or rented premises. In the case of rented proper7es the applicant
must obtain and provide to BPL wriRen approval from the property owner authorizing
the installa7on and fully indemnifying BPL with respect to same. The Grid Tied SSRG
must be capable of opera7ng parallel with BPL's Grid (in accordance with the
s7pulated technical requirements) with the intent to offset some or all of the
customer's own electricity usage.
5
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4.1.
Electrical GeneraYon Systems
Unless otherwise approved by BPL, to be eligible to connect and operate in parallel
with BPL's Grid, the SSRG system must be wind and/or solar powered with a maximum
aggregate capacity per facility as outlined in sec7on 2 of this document
The SSRG system may be single phase or three phase but its rated size is limited to 80%
of the size of the main breaker servicing the installa7on. Addi7onally, the phasing of
the SSRG system must match that of the electrical service that is in place.
4.2.
Small Commercial System Approval Requirements
Small commercial customers seeking to interconnect a SSRG system are required to
apply to URCA in accordance with URCA’s SSRG Applica7on Guidelines, which may be
obtained from URCA on or aier 28 February 2017. Sec7on 4.3 of this document shall
not apply to Small Commercial customers wishing to install SSRG systems.
4.3.
ResidenYal System ApplicaYon Process
Residen7al customers seeking to interconnect the SSRG system should complete and
submit the SSRG Applica7on Form, and an Electrical One-Line diagram (see Appendix 1
for sample) specifying all the components of the SSRG to BPL, together with copies of
the opera7on and installa7on manuals for the system components to be installed.
4.3.1. ApplicaYon Fee
An applicant for approval of a Grid Tied SSRG system shall pay a non-refundable
applica7on fee of $50 to BPL at the 7me of submirng the applica7on. BPL will review
the SSRG Applica7on and provide its response either approving or denying the
applica7on within twenty-one (21) days of receipt of a completed applica7on
containing all required informa7on.
6
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
Aier receiving wriRen approval from BPL to acquire the specified system, the
customer should make an applica7on to the
Ministry of Works for the required
electrical and building permits, including with these applica7ons a copy of the wriRen
approval from BPL.
4.4.
InterconnecYon
4.4.1.
Within six (6) weeks of receiving the completed applica7on, approved Electrical
Inspec7on Cer7ficate and all other required documenta7on, BPL will carry out
inspec7ons and tests in accordance with Sec7on 6 of this document, and will advise the
applicant in wri7ng whether or not the SSRG system qualifies for interconnec7on to
BPL's Grid. BPL may, if deemed necessary, apply addi7onal labelling and markers to
iden7fy the site as an approved SSRG installa7on.
4.4.2.
Where the SSRG system has been approved and passes all required inspec7ons, the
customer is required to complete the SSRG RegistraYon Form, and execute a SSRG
InterconnecYon Agreement with BPL prior to commencement of parallel opera7on.
The SSRG InterconnecYon Agreement outlines the applicable terms condi7ons for
opera7on of a grid 7ed SSRG system, including all applicable rates and charges.
4.5.
Unauthorised ConnecYons
BPL or URCA must grant approval in wri7ng, and the customer must have executed a
SSRG Interconnec7on Agreement with BPL, before any SSRG system is connected to
BPL's Grid. For the purposes of public and u7lity personal safety, BPL reserves the
right to disconnect the service to any customer who connects or has connected a SSRG
system to the electrical grid without wriRen authorisa7on from BPL.
Where BPL
decides to disconnect a SSRG system from the grid, it shall no7fy URCA within two (2)
days of effec7ng the disconnec7on, giving reasons for the disconnec7on. A customer
whose system has been disconnected pursuant to this power may have the maRer
reviewed by URCA by making a wriRen complaint to URCA.
7
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4.6.
Metering
BPL will furnish metering to measure the energy supplied from BPL's Grid to the
customer and the energy supplied to BPL's Grid by the customer whose SSRG system
has been approved by BPL or URCA, as the case may be, and installed by the customer
(“Customer-Generator”). Sample diagrams showing various configura7ons are shown
below.
8
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
SAMPLE METERING CONFIGURATION
Images courtesy of Aladdin Solar
9
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4.7.
Labelling
Any structure or building with a SSRG system that is not connected to a supply service
source and is a stand-alone system shall be marked in a conspicuous, legible, and
permanent manner to indicate the loca7on of the system disconnec7ng means and
that the structure contains a stand-alone electrical power system.
Buildings and structures with both a u7lity supply service and a SSRG system shall,
where prac7cable, have the disconnec7ng means grouped (in accordance with the
electrical code), or where such an arrangement is not prac7cable, shall have a
permanent plaque posted on or near each disconnec7ng means, indica7ng the
loca7on of all other service boxes supplying power to the building.
A permanent plaque or directory iden7fying all electrical power sources on or in the
premises shall be installed at each service equipment loca7on and at the supply
authority meter loca7on.
SSRG systems that store electrical energy shall be labelled in a conspicuous, legible,
and permanent manner with a suitable warning sign at the loca7on of the service
disconnec7ng means of the premises.
4.8.
Insurance
Customer-Generators are reminded that there are inherent risks related to any
electrical system. It is recommended that the Customer-Generator obtain and
maintain general liability insurance with respect to their system, however it is not a
requirement to do so. Obtaining and maintaining insurance is therefore in the
Customer-Generator's sole discre7on and BPL does not accept responsibility for any
losses suffered or liability incurred by the customer as a result of the CustomerGenerator’s SSRG system.
10
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4.9.
IndemnificaYon
Customer-Generators are advised to note carefully the provisions regarding mutual
indemnifica7on between the Customer-Generator and BPL, with respect to the design,
installa7on and use of SSRG systems.
BPL will not honour any damage claims submiRed with respect to the SSRG system
itself, or arising and demonstrated to arise out of the opera7on by the CustomerGenerator of an SSRG system.
4.10.
Future ModificaYons and Expansion
The Customer-Generator must obtain wriRen approval from BPL and the Ministry of
Works Electrical Inspec7on Department, prior to modifying, expanding or altering the
approved SSRG system.
An approved electrical inspec7on cer7ficate must be
presented to BPL and the Customer-Generator must obtain wriRen approval from BPL
before interconnec7ng the modified SSRG system to BPL's Grid. Where necessary the
customer may be required to execute a new versions of the SSRG Interconnec7on
Agreement.
4.11.
Renewable Capacity on BPL's Grid
For the overall safety and protec7on of BPL's Grid, the interconnec7on of all SSRG
systems, is limited to total installed capaci7es indicated in sec7on 2 as amended from
7me to 7me by BPL subject to URCA’s approval. The interconnec7on of any SSRG
system which exceeds the said limits shall require the prior approval of BPL and URCA.
4.12.
Customer-owned Equipment ProtecYon
It is the Customer-Generator's sole responsibility to protect its facility loads and
genera7on equipment and comply with the requirements of all appropriate and
relevant standards, codes and local authori7es.
11
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
4.13.
AddiYonal Fees
Customer-Generators may be required to pay BPL addi7onal fees for services related
to the installa7on of the SSRG system. Addi7onal costs payable by the CustomerGenerator to BPL above and beyond the Applica7on fee, if any, will be cost-based. A
Customer-Generator may apply to URCA for a review of any such fee charged by BPL.
12
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
Diagram 1
13
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
5.
BPL OPERATING CONDITIONS
This sec7on describes typical BPL distribu7on opera7ng and power quality condi7ons
within which the SSRG system should operate. These are representa7ve values that
BPL aRempts to maintain and includes some abnormal condi7ons that the SSRG
system should be designed to withstand. It is the Customer-Generator's responsibility
to ensure that all equipment operates correctly in this environment.
1.
System Frequency
BPL's Grid operates at 60Hz. Frequency devia7ons typically range from 58.5 to 61.5 Hz
for small con7ngencies resul7ng in modest disturbance where the SSRG system is
expected to remain connected to BPL's Grid.
For larger con7ngencies, broader
frequency varia7ons may occur such as when major genera7on or transmission is lost
and load shedding occurs.
The SSRG system protec7ve systems are expected to
operate as outlined in the Technical Interconnec7on Requirements sec7on below.
2.
System Voltage
BPL’s LV distribu7on Grid typically operates at voltages of 120/240V single phase and
120/208V or 277/480V three phase. Voltage devia7ons typically range from 112.8V to
127.2V (L-N on 120V base, 6%) for small con7ngencies resul7ng in modest disturbance
where the SSRG system is expected to remain connected to BPL's Grid. For larger
con7ngencies, broader voltage varia7ons may occur such as when major genera7on or
transmission is lost and load shedding occurs. The SSRG system’s protec7ve systems
are expected to operate as outlined in the Technical Interconnec7on Requirements
sec7on below.
14
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
6.
6.1
TECHNICAL INTERCONNECTION REQUIREMENTS
This sec7on provides the technical requirements to be met by the SSRG system in
order to qualify for interconnec7on to BPL's Grid and lists typical condi7ons and
response to abnormal condi7ons that the system is required to meet.
Except as
modified herein, the SSRG System must confirm to IEEE Standard 1547 "Standard for
Interconnec7ng Distributed Resources with Electric Power Systems".
All components, inclusive of but not limited to, Inverters, panels, charge controllers
and baReries, must be accompanied by the manufacturers’ specifica7ons sheets,
installa7on/opera7on manuals, and other details relevant to the inverters func7on.
These documents must be available at the 7me of applica7on, ini7al installa7on
inspec7on, and all subsequent inspec7ons/reviews. Voltage, current and power limits
and opera7ng points are key parameter sets must also be available for review. To
maintain system safety and compliance, Underwriters Laboratories (UL) lis7ng is
required for all electrical components UL 1741 is required for all inverters, converters,
controllers and Interconnec7on System Equipment and all Solar Modules are required
to be listed under UL 1703
All small wind turbine systems must meet UL 6142 requirements as well as any
applicable local code requirements.
6.1.
Over Current ProtecYon
The SSRG system must detect and promptly cease to energize for over-current fault
condi7ons within its system.
6.2.
AnY-Islanding
For an uninten7onal island condi7on, where the SSRG system energizes a por7on of
BPL’s Grid, the SSRG system shall detect the island condi7on and cease to energize
BPL’s Grid within a maximum of two seconds aier the forma7on of the island.
15
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
6.3.
Voltage Flicker
Voltage Flicker is an increase or decrease in voltage over a short period of 7me and is
normally associated with fluctua7ng loads or motor star7ng. A Flicker problem is sitespecific and depends on the characteris7cs of the changes in load. A Flicker is
considered objec7onable when it either causes a modula7on of ligh7ng levels
sufficient to be irrita7ng to humans or it causes equipment to malfunc7on. The RGS
shall not cause objec7onable Flicker for other customers on BPL’s Grid.
6.4.
Harmonic DistorYon
SSRG systems are to employ pure sine wave inverters and are expected to comply with
IEEE Standard 519 current distor7on limits with regard to harmonic current injec7on
into BPL’s Grid. The harmonic current injec7on arising from the SSRG system shall not
exceed the values listed in the table below – (excluding any harmonic currents
associated with harmonic voltage distor7on present on BPL’s Grid without the SSRG
system connected). Total current harmonic distor7on shall not exceed 5% of rated
current.
Total Harmonic Distor7on Limit
5.0%
Maximum Distor7on
Harmonic Numbers
6.5.
Even Harmonics
Odd Harmonics
h < 11
1.0%
4.0%
10 < h < 17
0.5%
2.0%
18 < h < 23
0.4%
1.5%
24 < h < 35
0.2%
0.6%
h > 35
0.1%
0.3%
Inverter Response to Abnormal Voltages and Frequencies
The SSRG inverter must be able to meet the disconnec7on criteria set out below:
16
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
6.6.
Voltage Condi7on (% of Nominal Voltage)
Maximum Time to Disconnect
V <50%
0.16 sec – (10 cycles)
50% <V< 88%
2secs – (120 cycles)
110% <V< 120%
1 sec – (60 cycles)
V> 120%
0.16 sec – (10 cycles)
Frequency
Maximum Time to Disconnect
F <59.4
0.16 sec – (10 cycles)
F >60.6
0.16 sec – (10 cycles)
Voltage Imbalance
Only three phase SSRG systems may be grid 7ed to incoming three phase services. In
these cases approximately equal amounts of genera7on capacity should be applied to
each phase of the three phase circuit.
6.7.
DC InjecYon
The SSRG system shall not inject a DC current greater than 0.5% of the unit’s rated
output current at the Point of Delivery aier a period of 6 cycles following connec7on
to BPL’s Grid.
6.8.
SynchronizaYon
SSRG systems that can generate an AC Voltage Waveform independent of BPL’s Grid
shall be connected in parallel only in combina7on with its synchronizing capabili7es.
The SSRG system shall synchronize to BPL’s Grid while mee7ng the Flicker
requirements previously indicated and causing no greater than a 5% voltage varia7on
at the Point of Delivery. Synchroniza7on may occur once BPL’s Grid is stabilized.
6.9.
InterconnecYon ProtecYon FuncYon Requirements
17
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
The system shall incorporate the following protec7ve func7ons:1) AC disconnec7ng;
2) An7-Islanding;
3) Automa7c synchronizing (inverters with stand-alone capability);
4) Under-voltage trip (on each phase for 3-phase equipment);
5) Over-voltage trip (on each phase for 3-phase equipment);
6) Instantaneous over-current trip (on each phase for 3-phase equipment);
7) Timed over-current trip (on each phase for 3-phase equipment);
8) Under-frequency trip; and
9) Over-frequency trip.
18
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
GLOSSARY
AlternaYng Current (AC): An electric current that reverses its direc7on at regularly occurring
intervals, known as the frequency which, in the case of The Bahamas, is 60 7mes per second.
AutomaYc Reclosing: This refers to the automa7c restora7on of power by devices following a
fault. It may involve a sequence of short interrup7ons before permanent restora7on or
cessa7on of power.
Capacity (gross): The full-load con7nuous ra7ng of the Renewable Genera7on System, under
specified condi7ons, as designated by the manufacturer. It is usually indicated on the nameplate
aRached to the equipment.
Customer-Generator: The person or en7ty accep7ng responsibility for the electricity account
associated with the Small Scale Renewable Genera7on (SSRG) system.
Delta (Δ) connecYon: A method for connec7ng three phase supply where each phase is
connected in series with the next, separated by a phase rota7on of 120 degrees. Compare with
Wye (Y) (star) connec7on.
Direct Current (DC): An electric current that flows in a constant direc7on. The magnitude of the
current does not vary or has a very slight varia7on.
DistribuYon System: The local poles, wires, transformers, substa7ons and other equipment
used to deliver electricity to consumers. (See Grid also)
Flicker: Flicker (voltage) is an unsteady visual sensa7on associated with changing ligh7ng
luminance caused by sudden and repe77ve increases or decreases in voltage over a short
period of 7me. It is normally associated with fluctua7ng loads or motor star7ng.
Frequency ProtecYon (over/under): Use of relays or other devices to protect lines or
equipment by causing circuits to open based on the degree by which the measured frequency
varies from a set value.
GeneraYon (Electricity): The process of producing electric energy from other forms of energy;
also, the amount of electric energy produced, expressed in WaRhours (Wh).
Grid: A network for the transmission of electricity throughout a region. The term is also used to
refer to the layout of an electric distribu7on system.
19
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
Grounding: An electrical connec7on to the earth or a body that extends from an earth
connec7on for the purposes of safety and voltage reference.
Harmonics: Distor7ons in the sinusoidal voltage and current waveforms caused by the
overlapping of the fundamental waveform at 60 Hz with other waveforms of integral mul7ple
frequencies of the fundamental waveform. Total harmonic distor7on (THD) is summa7on of all
the distor7ons at the various harmonic frequencies.
Hybrid System: A self-genera7on system that combines mul7ple power sources (such as solar
and wind) and is located behind a single electric u7lity service meter. Energy storage systems
such as baReries do not cons7tute a power source for the purpose of this defini7on.
SSRG InterconnecYon Agreement: The legal document authorizing the flow of electricity
between the facili7es of BPL and a Customer-Generator. SSRG systems must be permanently
interconnected and opera7ng in parallel to the electrical distribu7on grid of the u7lity serving
the customer’s electrical load.
InterrupYng Device RaYng: The highest current that a device is intended to interrupt safely at
rated voltage.
Inverter: A device that converts dc electricity into ac electricity. Some types are used for standalone systems (not connected to the grid) and others are designed as u7lity-interac7ve (grid7ed) systems to operate in parallel with the u7lity to supply common loads and may deliver
power to the u7lity.
Islanding: Islanding is a condi7on which occurs when an interconnected Renewable Genera7on
System con7nues to energize the facility (and the grid) aier a u7lity power interrup7on.
Industry prac7ce requires that the Renewable Genera7on System be disconnected promptly
according to applicable standards to avoid equipment damage and safety hazards to personnel.
Overcurrent ProtecYon: Use of a device or relay to protect the system by tripping it offline
based on the degree by which the measured current varies from a set value. The trip may be
instantaneous or aier a pre-set 7me.
Kilowag (kW): A measure of instantaneous power equal to one thousand WaRs of electricity
(See WaR).
Kilowaghour (kWh): A quan7ty of electricity usage equal to one thousand WaRhours.
20
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
Manual Disconnect switch: A manual switch required for interconnec7on to disconnect the
renewable genera7on source from the u7lity line.
Net Metering: An arrangement that permits a facility to offset its electrical consump7on against
energy delivered by the grid at the retail value and sell power in excess of its local consump7on.
Net billing: Arrangement that permits the u7lity (using two meters or one meter that separately
measures inflows and ou|lows of electricity) to sell power delivered to the customer at the
prevailing tariff, and buy excess power from the customer’s SSRG at a rate contracted by the
u7lity. The u7lity issues a net bill for each billing period.
Peak Wag: A manufacturer's unit indica7ng the amount of power a photovoltaic cell or module
will produce at standard test condi7ons (normally 1,000 waRs per square meter and 25 degrees
Celsius).
Photovoltaic (PV) Cell: An electronic device capable of conver7ng incident light directly into
electricity (direct current)
Photovoltaic (PV) Module: An integrated assembly of interconnected photovoltaic cells
designed to deliver a selected level of working voltage and current at its output terminals,
packaged for protec7on against environment degrada7on, and suited for incorpora7on in
photovoltaic power systems
Point of Common Coupling: The point where the electrical conductors of the u7lity’s
distribu7on system are connected to the customer’s conductors and where any transfer of
electric power between the customer and the distribu7on system takes place.
Point of Delivery: The point where the Renewable Genera7on System is electrically connected
to the electric u7lity for metering purposes.
Point of DisconnecYon: The point at an accessible loca7on where the disconnect switch used to
isolate the Renewable Genera7on System from the u7lity is located.
SSRG System: Small Scale Renewable Genera7on system. These are systems with the ability to
generate their own energy from acceptable renewable acceptable sources using approved
technologies.
Renewable Energy: Energy flows that occur naturally and repeatedly in the environment (such
as solar, wind, biomass) and can be harnessed for human benefit.
21
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
ResidenYal: Electrical Service category of dwellings single or mul7-unit, low rise, not being
operated as a resort, townhouse, hotel or condominium with each unit having it’s own metered
supply.
Root Mean Square (RMS): Used for AC voltage and current, this quan7ty equals the square root
of the average of the squares of all the instantaneous values occurring during one cycle. It is
considered as the effec7ve value of AC BPLause, for a fixed resis7ve load, the AC rms voltage
will produce the same hea7ng effect as a DC voltage of equivalent value.
Small Commercial: A commercial business customer which has a peak demand less that 50kW.
Solar Energy: The radiant energy of the sun, which can be converted into other forms of energy,
such as heat or electricity. Sunlight can be converted to electricity directly, as in the case of
photovoltaic (PV) applica7ons or indirectly as in the case of solar thermal applica7ons.
SynchronizaYon: The process of connec7ng two previously separated ac sources such as the
customer’s private genera7on system and the u7lity’s grid, to allow them to operate in parallel
(aier matching frequency, voltage, phase angles etc.).
Total Harmonic DistorYon (voltage and current): This is a single number representa7on of the
amount of distor7on of a voltage or current electrical waveform from a true sine wave.
Voltage protecYon (over/under): Use of relays or other devices to protect lines or equipment
by causing circuits to open based on the degree by which the measured voltage varies from a
set value.
Voltage (current) Waveform: The varia7on of voltage (current) over one cycle indicated by the
paRern which results when the instantaneous value of voltage (current) is ploRed with respect
to 7me over a cycle. Ideally, AC waveforms are represented by sinusoids and DC waveforms are
constant over 7me.
Wag (Electric): The electrical unit of power represented by the rate of energy transfer of 1
Ampere of electric current flowing under a pressure of 1 Volt at unity Power Factor.
Waghour (Wh): The electrical unit of energy represented by 1 WaR of power supplied to, or
taken from, an electric circuit steadily for 1 hour.
Wind energy: Energy present in wind mo7on that can be converted to mechanical energy for
driving pumps, mills, and electric power generators.
22
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.
Wye (Y, star) ConnecYon: A method for connec7ng three phase supply where each individual
conductor is connected to a common point, which may be grounded or ungrounded. Compare
with delta (Δ) connec7on.
23
Note:
BPL reserves the right to require addi7onal informa7on, if considered necessary, to process the Small Scale Renewable
Generator (SSRG) Applica7on.
Note: These SSRG Interconnec1on Requirements are subject to change.