FOCUS
Natural resources andenergy
Special
Connectionof generators to
Eskom’s
low voltagenetwork
T
he South African customer’s per-
spective on electricity usage is
evolving. This is a result of a num-
ber of factors, including the rising
electricity prices, the threat of load curtail-
ment at a time when South Africa is faced
with capacity constraints, the need to be
energy efficient and also the ever-rising
need to demonstrate good citizenship by
usinggreen energy.
These factors have resulted in some cus-
tomers (large and small) considering al-
ternative sources of energy. Among these
alternative energy sources considered,
is the increasing public interest to install
an own generator. There is particularly an
increasing interest by residential custom-
ers to connect PV installations on their
roof tops.
This article sets out the current challenges
that must be resolved first to enable such
a connection in a sustainable andmanage-
ableway. Thesegeneratorsmaynot begrid
tied, i.e. the customer generator operates
in parallel with the Eskom grid and supple-
ments the energy that would have other-
wisebeen imported fromEskom.
If the intended installation is planned to
be grid tied, permission is required from
Eskom as there are legal, safety and power
quality implications, whether energy is ex-
portedonto thegridor not.
Eskom is in the process of setting up the
legal, technical, metering and tariff frame-
work for the connection of small-scale gen-
erators to the low voltage network. There is
an existing approved process to allow gen-
erators connected to Eskom’smedium volt-
age andhigher voltagenetworks.
Customers are required to convert to
Eskom’s large power tariffs. The large
power tariffs have unbundled energy rates
and metering which supports time of use
(TOU) measurement. No premium is paid
for this energy – it is credited at the TOU
energy rateswhich reflect Eskom’s average
cost of energy.
TheEskomprocess formediumvoltageand
higher connections is available at
http://
-
SiteForIPPs/Pages/Guide_To_Independent_
Power_Producer_IPP_Processes.aspx.
Small and micro-generator
connection framework
Eskom’s framework for connecting small-
scale generators is in the process of
being developed and until such time it has
been completed, no small-scale generator
may be grid tied for safety, tariff and tech-
nical reasons.
This frameworkwill consider:
Resources tomanage the additional cus-
tomer requests (humanand financial).
Metering decisions – meters must be
capable of measuring the imports and
exportsof energy.
Customer understanding of implica-
tions that such installations can pose a
safetyand fire risk for thecustomer, and
that the necessary national standards
andaccreditationneeds tobe inplace in
order for such an installation to be safe
and that it is installedby accredited and
authorisedpersonnel.
Administration andbilling implications.
Revenue impacts, tariff structures, tariff
ratesand rates for creditwhichwill need
to be approved by the National Energy
Regulator of SouthAfrica (NERSA).
Technical issues – Eskom’s present low
voltage network operating and mainte-
nancepractices arenot compatiblewith
the connection of low voltage micro
generators, and the connectionof these
generators (even if they are not export-
ing into the grid) presents a safety risk
for Eskom’s field staff andhence cannot
be connected until the low voltage op-
erating procedures have been revised
to ensure the safety of utility staff and
thepublic.
Processesarebeingput inplace for cus-
tomers to apply and make the connec-
tions legal.
Rules regarding month to month bank-
ing (carry-over of energy).
Contracting – comprehension of cus-
tomer andEskomobligations in compli-
ance with the Consumer Protection Act
andother technical legislation.
Safety of Eskom field workers and
customers.
Until the framework is in place, customers
connected at low voltage are not allowed
to connect any generator that is grid tied,
as this places the safety of the public and
Eskom employees at risk. Eskom will not
allowmeters to turnbackwards andhas the
right todisconnect any supply that does not
havepermission tobegrid tied.
Enquiries
An Eskom work team is working on the
framework to be approved within Eskom
and, where required, by NERSA. Eskom is
alsoworking closelywith the SouthAfrican
Local Government Association (SALGA) to
ensure consistent application and connec-
tionprocesses.
For any queries for these types of connec-
tions, please refer them directly to the Cus-
tomer Services Group, Grid Access Unit
which is sponsoring the project – contact
Ravi Moonsamy (project leader for the low
voltagesmall-scalegenerator framework) at
.
RAVI MOONSAMY,
project leader for the low voltage, small-scale generator framework, Eskom
November 2014
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