IEEE Electrification Magazine - June 2017 - 46

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Power Profile (kW)

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Power Profile (kW)

Figure 22. The power profile of the Keating Nanogrid.

Time (h)
Figure 23. The power exchange with the IIT Microgrid.

4 p.m. and 6 p.m., and it even exports power to the IIT
Microgrid from 1 p.m. to 4 p.m. when the building loads can
be fully fed by on-site PV power output. Additionally, batteries are charged either when the building loads are light or
when the PV power output is sufficient to serve the building loads, and they are discharged either when there is no
solar energy to serve heavy building loads or when the PV
power output cannot fulfill the requirement of supplying
the building loads.
In the case of an outage in the IIT Microgrid, the Keating
Nanogrid can intentionally isolate itself from the microgrid.
Upon intentional islanding, both ac and dc subsystems will
instantaneously provide adequate power to their connected
loads by utilizing the associated battery storage, resulting in
only a momentary fluctuation (on the order of several
cycles) in power quality. Then, the Keating Nanogrid will
run autonomously as an island and continue to power its
loads by utilizing on-site available resources. In fact, the
battery energy storage together with the PV generation system included in the Keating Nanogrid can provide uninterrupted power to all the critical loads for up to 24 hours.

Conclusions
A nanogrid is a technologically simpler microgrid, but its
implementation and operations are more flexible than a
microgrid. Meanwhile, the diversity and modularity of

46

I E E E E l e c t r i f i c ati o n M agaz ine / j un e 2017

nanogrids make them ideal for forming the basis for a
microgrid. The Keating Nanogrid is a successful demonstration of how a self-controlled nanogrid can benefit both
microgrid operations and local building loads. Accordingly,
nanogrids open a new door to implementing a smart grid
in a bottom-up manner. With the prevalence of nanogrids,
power systems will inevitably undergo structural and
behavioral changes. Through strategically interconnecting
individual nanogrids, power system operations will gain a
significant improvement in efficiency, sustainability, reliability, and resilience.

For Further Reading
M. Shahidehpour and J. F. Clair, "A functional microgrid for
enhancing reliability, sustainability, and energy efficiency,"
Electr. J., vol. 25, no. 8, pp. 21-28, Oct. 2012.
M. Shahidehpour and M. E. Khodayar, "Cutting campus
energy costs with hierarchical control: The economical and
reliable operation of a microgrid," IEEE Electrific. Mag., vol. 1,
no. 1, pp. 40-56, Sept. 2013.
OSIsoft. (2017). PI system: From data to knowledge to
transformation. [Online]. Available: http://www.osisoft
.com/software-support/what-is-pi/What_Is_PI.aspx
Aquion Energy. (2015). BMS-200 battery monitoring system
technical manual. [Online]. Available: http://www.solarpanelsplus.com/solar-battery/Aquion_Energy_BMS-200_Technical_
Manual.pdf
Aquion Energy. (2015). Aspen 48S-2.2 battery. [Online].
Available: http://info.aquionenergy.com/hubfs/01_Product_
Documentation/Aquion_Energy_Aspen_48S-2.2_Product_
Specification_Sheet.pdf
Schneider Electric. (2015). Xantrex™ XW MPPT 80 600:
Operation guide. [Online]. Available: http://pdf.wholesalesolar.
com/controller%20pdf%20folder/semppt80600-ChargeCon
trollermanual.pdf
Schneider Electric. (2015). Conext™ XW+ inverter/charger:
Conext XW+ 6848 NA owner's guide. [Online]. Available: http://
solar.schneider-electric.com/wp-content/uploads/2014/08/
Conext-XW-Owners-Guide-NA-975-0240-01-01_Rev-E_
ENG.pdf
Schneider Electric. (2015). Conext™ ComBox communication and monitoring device: Owner's guide. [Online]. Available: http://www.xantrex.com/documents/Accessories/
Combox/975-0704-01-01_RevA(Vendor).pdf
Solectria Renewables. (2014). PVI 14TL installation and
operation manual. [Online]. Available: https://solectria.com//
site/assets/files/1426/docr-070351-e_manual_installation_
and_ operation_ pvi_14_-20tl.pdf
Aris Wind. (2015). Wind/solar off-grid lighting solution.
[Online]. Available: http://ariswind.com/wp content/
uploads/2015/10/Aris-RPU-Oct15.pdf

biographies
Mohammad Shahidehpour (ms@iit.edu) is with the Illinois
Institute of Technology, Chicago.
Zhiyi Li is with the Illinois Institute of Technology,
Chicago.
Wenlong Gong is with the Illinois Institute of Technology,
Chicago.
Shay Bahramirad is with ComEd, Chicago, Illinois.
Marc Lopata is with Azimuth Energy, St. Louis, Missouri.
http://www.osisoft http://www.solarpanel http://www.splus.com/solar-battery/Aquion_Energy_BMS-200_Technical_ http://info.aquionenergy.com/hubfs/01_Product_ http://www.pdf.wholesalesolar http://http:// http://solar.schneider-electric.com/wp-content/uploads/2014/08/ http://www.xantrex.com/documents/Accessories/ https://www.solectria.com// http://www.ariswind.com/wp
Table of Contents for the Digital Edition of IEEE Electrification Magazine - June 2017
