IEEE Power & Energy Magazine - May/June 2017 - 73

for the entire solution. In this case, the role of the distribution system operator is to coordinate the integration of these
microgrids by a control platform where the boundary and
responsibilities are clearly identified at the point of common
coupling. The economic viability of this solution is defined
by the owner's business model. This doesn't imply a major
change in the tariffs because all investments are the responsibility of the owner. Nevertheless, a high penetration of
this solution will impact the distribution system operator's
business because of a lower infrastructure requirements.
Examples of these type of applications are community-based
microgrids and campus microgrids.
In the second track, in the multiple-agent microgrid
scheme, the ownership of different microgrid assets is not
unique. In fact, some DG assets (e.g., residential PV panels)
could be owned by private homeowners and/or small businesses, and others could be owned by a local authority and/
or an entire community. While the DG facilities can have
several owners, the distribution system operator is the only
owner of the network infrastructure used by the microgrid.
It is important to note that additional devices installed to
enable microgrid operation, such as batteries, on-load tap
changers, control and communication infrastructure, can be
owned by different actors.
The multiple-agent microgrid is implemented in a subset of
the existing distribution system infrastructure (i.e., using the
existing network as a starting point), and therefore the distribution system operator is responsible for managing the resources
(e.g., DG units, and battery systems). Here, it is important to
note that the quality of supply inside the microgrid must satisfy all distribution system regulatory requirements. In this
framework, the microgrid can be integrated through one or
more points of common coupling.
From a business perspective, microgrids are usually not
economically viable in Chile. In fact, Chile does not subsidize
the installation of residential PVs; power injections into the
system are accounted through a net billing scheme. Considering current energy prices, residential PVs are not profitable
as the capital recovery time can be approximately ten years.
Hence, the implementation of a microgrid in Chile usually
requires financial help from third parties such as private companies (i.e., mining companies in towns close to their extractive operations) or from government subsidies.
The resilience of microgrid systems during low-frequency, high-impact events can help justify subsidies. The
size of the subsidy will depend on the level of self-supply
that the policy maker wishes to achieve. A system designed
to supply only critical loads when the main grid connection
is lost requires less investment than a system designed to
supply normal community consumption.

Summary
Communities benefit from more robust distribution systems
that can endure technical, social, economic, and environ-

may/june 2017

mental disturbances without losing functionality and can
quickly be restored to normal operating conditions. This
characteristic may be achieved through the implementation of smart grids solutions such as microgrids. Lessons
learned from the isolated microgrids discussed here contribute to the development of a design methodology for larger
smart grid solutions at the distribution level, as shown by
two major projects to be developed in Chile. The experience and learning outcomes from these projects have led to
the production of two transition schemes for the integration
of microgrids at the distribution level that can provide a
starting point for distribution planners, policy makers, and
other stakeholders.

Acknowledgments
This work has been partially funded by joint ConicytChile/RCUK-UK project: Disaster management and resilience in electric power systems (Newton-Picarte/MR/
N026721/1) by CONICYT/FONDAP/15110019 and Ayllu
Solar project.

For Further Reading
J. C. Araneda, H. Rudnick, S. Mocarquer, and P. Miquel,
"Lessons from the 2010 Chilean earthquake and its impact on electricity supply," in Proc. Int. Conf. Power System Technology (POWERCON), China, 2010, pp. 1-7.
M. Panteli and P. Mancarella, "The grid: Stronger, bigger, smarter?," IEEE Power Energy Mag., vol. 13, no. 3, pp.
58-66, 2015.
M. Panteli and P. Mancarella, "Modeling and evaluating the resilience of critical electrical power infrastructure
to extreme weather events," IEEE Syst. J., no. 99, pp. 1-10,
Feb. 2015.
G. Jiménez-Estévez, R. Palma-Behnke, D. Ortiz-Villalba,
O. Núñez, and C. Silva, "It takes a village," IEEE Power Energy Mag., vol. 12, no. 4, pp. 60-69, July/Aug. 2014.
K. Ubilla, G. Jiménez-Estévez, R. Hernández, L. ReyesChamorro, C. Hernández, B. Severino, and R. PalmaBehnke, "Smart microgrids as a solution for rural electrification: Ensuring long-term sustainability through cadastre
and business models," IEEE Trans. Sustain. Energy, vol. 5,
no. 4, pp. 1310-1318, Oct. 2014.

Biographies
Guillermo Jiménez-Estévez is with the Universidad de
Chile, Chile.
Alejandro Navarro-Espinosa is with the Universidad de
Chile and Systep, Chile.
Rodrigo Palma-Behnke is with the Universidad de
Chile and SERC, Chile.
Luigi Lanuzza is with Enel Green Power, Italy.
Nicolás Velázquez is with Universidad Autonoma de
Baja California, Mexico.
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