Remote monitoring and supervisory control

Remote monitoring refers to the real-time observation of key characteristics of a
production station that are relevant to the Network Operator and other market
participants, such as Aggregators Remote control involves intervening in the operation
of a station to adjust its performance based on target commands. For RES stations,
standard adjustments typically involve limiting the plant’s maximum active power output
to a specified value, known as the (‘active power setpoint’).”

The obligation to install remote monitoring and remote control systems shall, in
principle, apply to independent producers’ plants with electricity compensation and an
installed capacity exceeding 400 kW, connected to the interconnected grid, regardless
of the generation technology or activation date For self-consumer stations, remote
monitoring and control will be carried out at a later stage.

The installation of equipment for remote monitoring and remote control in power
stations with an installed capacity exceeding 400 kW is mandatory by Law 5106/2024.
Specifically, Articles 111 and 118 of the law outline the obligation, specify deadlines for
equipment installation and make provision for penalties in case of non-compliance by
the producer.

Stations with an installed capacity exceeding 400 kW and up to 1000 kW are required
to install the equipment within eight (8) months from the notification of the requirements
of HEDNO, i.e. by 13/02/2025.
Power plants with an installed capacity exceeding 1000 kW are required to install the
equipment within eight (8) months from the publication of Law 5106/2024, i.e. by
31/12/2024.

In the event of failure to install the equipment within the prescribed time limit, Article
111 provides for the deactivation of the connection of the station to the Network. In
addition, for stations with a capacity exceeding 1 MW, Article 118 also provides for
financial penalties.
After 31/12/2024 and after 13/02/2025, the Operator will decline connection to the grid
of stations with capacity exceeding 1000 kW and stations in the 400-1000 kW power
range respectively, in which the required equipment has not been installed.

Within the time limit provided for in Law 5106/2024, the producer must submit to the
RES/CHP platform a signed Declaration of Compliance stating that they comply with
the requirements for remote monitoring and remote control as specified in the latest
version of the text “Equipment used in the reception and execution of remote
monitoring/control commands for RES & CHP Stations” of HEDNO as part of the
application of articles 111 and 118 of Law 5106/2024. The Declaration of Compliance
may also be submitted by the station’s Technical Manager, as designated by the
producer. To confirm it, the signed and fully completed ‘Equipment–Station Control
Protocol’ and ‘Equipment–SCADA/DMS Control Protocol’ must be attached.
HEDNO will carry out the necessary tests and checks in order to verify compliance and
in case of false or inaccurate Declaration, in addition to the deactivation of the
connection of the station, the declarant will have the consequences stipulated by the
Law.

The costs of installation, maintenance and operation of the equipment shall be borne
by the producer.
The operation of the remote monitoring and remote control equipment requires the
telecommunication connection with the command system of the Network Control
Centers of HEDNO.

HEDNO has published the equipment specifications and their intended purpose on its
website. The equipment will be installed downstream of the HEDNO/producer
ownership boundary, i.e., within the production station. The selection of the equipment
type is the producer’s responsibility. HEDNO does not intend to recommend or verify
the suitability of equipment from any specific type or manufacturer. The only exception
is the router, which is provided by the Operator.

The equipment installed for remote monitoring and remote control is provided by the
producer. Specifically, the router is supplied by HEDNO in order to meet the increased
cyber-security requirements that have been specified.

The technical requirements published on HEDNO’s website include:
i) The commands to be received by the production station and the signals and
measurements to be sent by the station to the SCADA/DMS of HEDNO
ii) The communication protocol between the station and the SCADA/DMS of HEDNO
iii) The equipment’s programming requirements
iv) The Specifications for Telecommunications equipment, excluding the router.
The requirements that have been published do not concern self-consumer stations and
stations connected to Non-Interconnected Islands.

The commands to be provided by HEDNO to the production station are as follows:
i) command for the maximum permissible injection power (“active power
setpoint”) specified as either a fixed value or a %;
ii) command for complete power shutdown;
iii) command to open the Automatic Disconnect Switch (in emergency situations
only).
In the future, there is a provision to send commands for the regulation of reactive
power/power factor/voltage and frequency support for those Stations that have the
capacity and/or the obligation under EU Regulation 2016/631 (“RfG”).
It is clarified that the Equipment must comply with the current legislative framework for
the operation of RES Stations as well as with the Final Connection Offer. These
determine the maximum permissible injection power into the Network. If any active or
reactive power setting commands (specified as either a fixed value or a percentage)
are received from HEDNO’s SCADA/DMS that result in non-compliance, the equipment
must adjust accordingly to ensure compliance at all times.
For example, in stations with a permanent 27% power limitation (see question 24), the
command to specify active power as a percentage refers to the maximum allowable
injection power, which is already restricted by the 27% limit. Therefore, an active power
setting command of 50% results in a limitation of (100 – 27) × 50% = 36.5%.

With the installed equipment, the following statuses must be monitored:
i) The status of the Automatic Disconnect Switch (closed or open) and its
ability to be controlled remotely or locally (remote or local)
ii) The status of the earthing (closed or open)
iii) The control status of the equipment (remote or local), communication or
loss of communication between the equipment and the production units and
the health status of the relay and the equipment
iv) Decoupling protection alarms
n) Confirmation that the relevant command has been received from HEDNO or
other operator.
vi) Relevant signals relating to reactive power/power/voltage factor determination
and frequency support modes.

The measurements sent to HEDNO relate to:
i) The active and reactive output power of the whole station;
ii) The current and the voltage per phase;
iii) The frequency, and
iv) The power factor.

Limiting active power is generally required for allocation purposes, in which case
generating stations or their Aggregators may need to reduce their production capacity
during certain hours. This is necessary when the energy they are producing exceeds the
demand of the Greek Interconnected System and the energy the country is permitted to
export. However, an active capacity limitation may also be requested for reallocation
purposes, such as when congestion in the System or the Network necessitates further
reduction of capacity from RES stations.
Finally, power limitation may also be provided as a service to IPTO, which operates the
balancing market, when stations are called upon to supply a ‘downward frequency
restoration reserve,’ i.e., a real-time power reduction, to help regulate the System’s
frequency.
Depending on the purpose of the limitation, the production station may or may not be
compensated for the lost output, or may even be compensated for providing downward
frequency restoration redundancy.

HEDNO is focusing on modernizing its network through digitalization and active
management.
Remote monitoring and control applies to all RES plants exceeding 400kW,
irrespective of their participation in the market, and will cover the requirements for
system stability and better management of the Network. With stations exceeding 400
kW expected to be integrated into HEDNO’s control centers, the operator will be able to
remotely manage over 70% of the RES capacity currently connected to the network (as
of 2024). In addition to the Law, the option to install the equipment is outlined in the
producer Connection Contracts and the HEDN Code (Article 75)

The disconnection of a station from the Network by opening remotely operated or nonremotely operated Network switches is an emergency measure. In addition to the
infrastructure for generating energy, the generating station features consumption
infrastructure critical to its operation. Through the remote monitoring and control
system, in addition to ensuring the continuity of critical loads at the station (e.g., alarms,
telecommunications, and network monitoring for automatic restoration), the station can
continue producing energy—albeit at a reduced level—rather than being fully
disconnected as it has been in the past.
The operator reserves the right, in exceptional circumstances, to disconnect the station
from the network using network means if the station fails to comply with the given order
for any reason.

The remote monitoring and control systems that a generating station may have, as
required by an Aggregator for market participation, covers only some of the operational
requirements set by HEDNO. HEDNO does not only specify requirements for
monitoring the active power of a power station or only commands to reduce it, but also
sets additional requirements related to the operation of the Network. Therefore, a
producer must ensure that the equipment they install meets all the requirements
outlined in HEDNO’s specifications. While most of the requirements will be utilized
immediately, others are expected to be implemented in the future. The Operator has
specified equipment that will serve the current and future Network, and producers will
be able to participate in the current and future energy market.

The Operator, or any other entity, issues a command to a station to adjust the injection
power to a maximum value (in percentage or absolute value). The station shall comply
with the command and adjust its power to a value less than or equal to the command
given. Stations without equipment for continuous regulation and with multiple
generating units may disconnect some units to adjust their output to a level equal to or
below the specified command. For the installation and operation of the remote
monitoring and remote control system there is no requirement
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for the replacement of the existing power generation equipment (power inverters or
generators).

Law 5106/2024 does not exempt CHP stations with an electrical capacity exceeding 400
kW from the obligation to install remote monitoring and control equipment. Similarly, EU
Regulation 2019/943 as well as Article 9, par. 1B of Law 3468/2006, which identifies the
stations that do not have priority allocation (i.e. the stations that may be required to
disconnect), does not exclude CHP stations.

The producer must ensure that their telecommunications connection remains
operational. After a command has been sent, the producer shall acknowledge receipt.
Penalties for failing to execute a command, along with acceptable tolerance limits for
magnitude and frequency deviations in network stations, will be defined and
established in the next period.

Disconnections are currently imposed to meet primarily market requirements and
system stability, and secondarily Network requirements. Market-related disconnections,
concerning both supply (generation) and demand (load), are not within the
responsibility or competence of the Operator. For Network needs, stations will be
disconnected or limited due to maintenance or damage to Network elements, with the
same frequency as currently, to ensure the proper functioning of the Network.

In general, the Operator shall open the Interconnection Circuit Breaker (ICB) of the
Station in exceptional cases associated with avoiding the phenomenon of islanding in
the Network, ensuring the safety of people, the environment and technical equipment,
as well as in cases of non-compliance with the commands received by the Operator.
In cases where the Switch is opened by the Operator, it will be closed by the Producer
or the Technical Manager of the station, after consultation with the Operator. It is
recommended that the Producer or their Technical Manager continuously monitor
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the status of the ICB to ensure they are promptly aware if it is opened at the Operator’s
request, however rare that may be.
The Operator shall not be obliged to compensate the Producer for any loss of revenue
due to the opening of the ICB in the above exceptional cases.

The limitation of the power of a RES station may be imposed not only for allocation but
also for reallocation purposes due to congestion in the System or the Network, where
no distinction is made between RES Stations with and without priority allocation. In
addition, remote monitoring and remote control will enable the Operator to monitor
power flows in real time, allowing better management of its Network, which will also
allow for even greater penetration of RES. Law 5106/2024 outlines the obligation to
install remote monitoring and control systems, not the purpose for which they will be
installed.
Article 9, para. 1B of Law 3468/2006 refers to the priority of allocation only. It does not
refer to the priority to be given for reallocation purposes or to necessary disconnections
due to the management of the Network.

The restriction imposed by Article 10 of Law 4951/2022 and specified by relevant
Ministerial Decision, is a limitation applied on a permanent basis in order to make
better use of the existing RES margins in the Network. Any market limitations that may
be imposed, which depend on the total production and load in the country at any hour
of the day, are additional to the permanent limitations. Any exceptional limitations due
to congestion on the System or the Network shall also be additional.

The protection relay featured in each station, from which the required measurements
could be taken, is powered by the protection windings of the voltage and voltage
transformers, which usually have a maximum error of 1% and 0.5% respectively at
nominal values, so taking into account the error of the relay itself (of the order of 0.5% at
nominal values), it follows that the measurement accuracy requirement of the technical
description (<1.5% at nominal values) is met.
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Thus, based on the specifications set, the accuracy of measurement of active and
reactive power for the purposes of remote monitoring can be achieved with the normal
installed equipment in the MV.
However, for some older relay types, the error may be larger (around 2%). To achieve the
required measurement accuracy of less than 1.5%, an independent meter with appropriate
specifications should ideally be added, or the controller should be replaced with a more
modern one. Nevertheless, it is recommended that measurements are taken from the
existing protection relay in order to be able to verify the correct operation of the individual
protections in future incidents. Therefore, and for the convenience of the producers, it is
acceptable to take measurements from the existing relay, even if the required accuracy
cannot be achieved with an old-type relay.

If the production station already has a system with which it is remotely
monitored/controlled by the Energy Control Centre of Crete, there is currently no such
requirement for the producer.

The announcement of HEDNO and the publication of the technical specifications for
the remote monitoring/control systems concerns the owners of RES and CHP Stations
of the Interconnected Network with electricity compensation and an installed capacity
exceeding 400 kW.
Stations with net metering or virtual net metering are not compensated, as the injected
energy is offset against the absorbed energy. At present, these stations are not
required to install remote monitoring and control systems. Article 111 of Law 5106/2024
makes provision for the Operator to issue specifications for remote monitoring/control
systems for this category of stations as well. Therefore, the 8-month compliance period
will apply to these stations when the relevant specifications are issued and published
on the website of HEDNO.

The control of the communication of the equipment with HEDNO’s SCADA will be
conducted at the final stage of the station’s connection to SCADA. Tests for the
exchange of signals and commands can be
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executed using protocol Simulator IEC 60870-5-104.

According to the second edition of the technical requirements for equipment used to
receive and execute monitoring/control commands, storage space for recording timestamped events is not required.

Simultaneous dispatch can be performed, as the values of active and reactive power,
while related, can be determined independently.

The command that will be executed will be the one that leads to the minimum absolute
value of reactive power, in the case of reactive power control, or to the closest absolute
value to one (1) for the power factor, in the case of power factor control.

The default value for the command with S/N: 60 of Table 4 in the Technical
Specification is “Ο” (Status: Inactive). Active power control is independent of the value
of the S/N 60 command

The 4G/5G interconnection with a SIM card is provided by the HEDNO router. If
the producer has an existing telecommunications medium for Internet connectivity, they
have the option to interconnect the provided router with the existing Internet connection
via Ethernet, instead of using a SIM card and external antennas.

The provision of the required antennas is at the discretion of the producer, provided
that the antenna’s characteristics and its connection to the network equipment meet the
requirements specified by HEDNO. As regards the SIM card, the choice of the
telecommunications provider is at the discretion of the producer. It is recommended to
select the appropriate telecommunication provider depending on signal strength and
quality at the point of installation of the equipment and on the infrastructure of the RES
producer.
The specific solution with the antennas will be used if the producer interconnects the
network equipment via a SIM card. If the interconnection is made with another
telecommunication medium (e.g. DSL) then the installation of antennas is not required.

The router is powered via redundant dual input with 2 pins per terminal. It
supports +12V to +125 V DC and -12 V to -125 V DC. DC power supply and
cables are not included in the equipment package.
• The maximum power consumption of the router is 20 W and the average
power consumption is 18.3 W.
• The maximum dimensions of the router are: Height: 15 cm, Width: 12 cm,
Length: 13 cm.
• The router can be mounted on a DIN rail.

These are the step to be followed:
1. Please visit https://ape.deddie.gr/apewebportal-ws/ and log in using your TaxisNet
login credentials.
2. Select “Manage Connection Requests”.
3. From the list of displayed applications, select any area in the row of each
application, except for the application’s S/N, to navigate to the section of the screen
with the Producer/HEDNO Actions.
4. Select “Add Producer Energy” and from the list of available options choose
“Supply Router for remote control” as the energy type.
5. After selecting the action, a screen will appear prompting you to fill in the router’s
shipping information and your phone number.
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6. Then, select the RF generation button to generate the RF and type “Submit”.
The cost for the acquisition of the router is €1736, including VAT. Please note that after
submitting your router supply request, you will receive an email confirming the payment
amount and the RF.
You are required to pay the router prior to the submission of the Responsible
Declaration of Compliance and the accompanying protocols.

The steps for submitting the Declaration of Compliance and the accompanying
protocols are as follows:
1. Please visit https://ape.deddie.gr/apewebportal-ws/. and log in using your TaxisNet
login credentials.
2. Select “Manage Connection Requests”
3. From the list of displayed applications, select any area in the row of each
application, except for the application’s S/N, to navigate to the section of the
screen with the Producer/HEDNO Actions.
4. Select “Add Producer Energy” and from the list of available options choose “Supply
Router for remote control” as the energy type.
5. On the next screen, you will be asked to submit the Declaration of Compliance, the
Station Equipment Control Protocol and the SCADA Equipment Control Protocol
separately.
6. If the Station is represented by an Aggregator, then from the list of Aggregator
options, please select the Aggregator that represents you or if there is no
Aggregator available in the options, enter the name of the Aggregator. If there is no
Aggregator representations, please select “I am not represented by an Aggregator”.
7. Finally, please select “Submit”.
You are required to pay the router prior to the submission of the Responsible
Declaration of Compliance and the accompanying protocols. Otherwise, it is not
possible to complete the “Installation of Remote Monitoring/Control Equipment”
procedure.

According to the router manufacturer, a data service intended for network equipment
(not a mobile phone) that supports the automatic configuration of internet settings
(automatic APN) should be used, and it must be associated with a contract rather than
a prepaid service.
More specifically, the SIM card should have the following features:
• Voice and Data Contract card that supports both voice and data services (rather than
just data) with a contract rather than a prepaid card
• Public ΙΡν4 address (avoid CG-ΝΑΤ): do not use the provider’s CG-NAT. The SIM
card should have its own public IPN4 address
• IPSEC VPN creation support: the card should support the creation of IPSEC VPN
tunnels without restrictions
• Embedded ΑΡΝ: the card shall have a pre-configured (embedded) APN for the data
service.
These specifications ensure that the router will operate seamlessly, providing a
secure connection and access to all necessary remote management functions.