IEEE Power & Energy Magazine - May/June 2017 - 26

the second 2 MW would experience 26.6% curtailment
This significant curtailment increase is due to the coincident nature of all of the PV capacity on the circuit and
would decrease for other types of distributed generation or
LTC sgs Connect
if microclimate effects varied the output of PV systems on
this circuit.
The presented analysis suggests that additional PV capacity and participation in FICS will likely only be economical
in the range of 2-4 MW and is dependent upon the size of
the systems being installed. This assumes an upper limit of
15% of incremental curtailment. We selected this upper limit
DER Site
based on experience, but the true economic limit could be
higher or lower and depends on specific considerations and
MP1
the risk tolerance of the PV developer. Using these assumpsgs Connect
tions, FICS could potentially double hosting capacity from
the original 4.5 to 9 MW of total DER capacity (i.e., two existing biodigesters at 0.5 MW with one under FICS control, one
2-MW
existing 4-MW PV project, and the potential to add 4 MW of
PV Generator
additional PVs).
Figure 8 depicts the curtailment across the year for
the
case with 4 MW of additional PV capacity as a single
MP2
MP3
project. Other additional PV capacity cases present similar curtailment periods but with different magnitudes. As
expected, there is a clear increase in curtailment during the
summer period. This information enables DER developers
figure 5. The use of ANM to manage overvoltage at the POCC.
to assess any curtailment mitigation measures that could
enhance the flexible interconnection operation throughout
If this same 4 MW would connect as two separate 2-MW the year, such as pairing with responsive demand or flexprojects, however, the row presenting the "% incremental ible energy storage.
The curtailment results in Figure 8 are specific to the
curtailment" would instead represent the curtailment each
2-MW project would endure; the first 2 MW would experi- DER and location being studied but are typical of the types
ence 0.6% curtailment, as shown by the first column, and of analysis results for additional flexible PV capacity being
added to distribution systems that
are considered "full" according to
traditional methods. The results
Substation
are also heavily influenced by the
load and other DERs in the area.
MP1
However, it has been shown that
once lost revenue from curtailment
is taken into account, the use of
ANM can reduce the cost of interconnection of up to and over 80%.
This has been confirmed in the
Existing
Existing
Flexible Plug and Play Project,
DER Site
DER Site
led by the distribution utility UK
Power Networks, in the southeast
FICS
of England, United Kingdom, as
DER Site
also reported in the MIT Energy
4-MW
500-kW
sgs Connect
Initiative's "Utility of the Future"
PV Generator
Biodigester Generator
report. Access to the type of study
results shown above provides DER
450-kW
developers with the opportunity to
Biodigester Generator
consider a flexible interconnection
option and explore the impact on
figure 6. The management of thermal capacity constraint at a substation by ANM
the
finances of their DER project.
due to increased distributed generation connection.
Substation

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may/june 2017

Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - May/June 2017