IEEE Electrification Magazine - December 2016 - 52

TECHNOLOGY LEADERS

Stochastic Impacts of Metaheuristics
from the Toaster to the Turbine
By Mark R. Knight

KAY, LET'S BE HONEST-
there's pretty much nothing on metaheuristics in
this article other than one short section, so don't let the title distract you.
The focus of this issue of IEEE Electrification Magazine and of this article is
on understanding and demonstrating how transactive energy systems
can have an impact on nonbulk
power applications. So what does
that include? Well, as it turns out, a
lot. The bulk power system with its
larger generators and high-voltage
transmission lines requires lots of
planning, investment, and maintenance. These are assets that have
lives measured in decades, and much
of their topology is relatively fixed.
The bulk system is also well monitored and heavily networked, i.e.,
there are multiple paths for the electricity to flow, and therefore alternative paths for power flow in the event
of a disturbance.
It can still have failures, and we
have seen many examples of that,
where equipment becomes overloaded or fails due to defects or poor
maintenance or where the monitoring was either not sufficient or where
available technologies were not adequately leveraged. Even though it is
more resilient than the distribution

Digital Object Identifier 10.1109/MELE.2016.2614218
Date of publication: 5 December 2016

system, the power still has to find a
path to flow, and it must be balanced
in real time, which, especially after a
failure, adds to everyday challenges,
like congestion.
While the practices for measuring
the economic cost of congestion are
specific to each market, "those pesky
laws of physics" are still the same
(Erich Gunther-interoperability,
transactive systems, and smart grid
guru). Transmission congestion is a
critical challenge to the nation's electricity infrastructure that costs billions of dollars each year. This is why
the Pacific Northwest National Laboratory (PNNL) is developing innovative high-performance-computing
techniques that can assess unused
power transmission capacity in real
time to better manage congestion in
the power grid. If successful, PNNL's
real-time transmission-rating technology could save businesses and
consumers billions of dollars per year
by reducing power generation costs,
reducing transmission losses, minimizing transmission congestion
costs, and deferring investment in
costly new infrastructure. This is
nice, but it is not something that we
can apply to the distribution system.
Yet the distribution system is changing, and we need ways to optimize it.
Distribution systems, with the
exception of the heavily networked
metropolitan areas, are typically radi-

IE E E E l e c t r i f i c ati o n M agaz ine / DECEMBER 2016

al in nature, with sectionalizing
switches that can be used to do some
reconfiguration in the event of disturbances or planned work. But it is
this limited networking and susceptibility to unexpected or unanticipated
changes that makes the distribution
systems of the United States the
ideal places to implement transactive
systems, and, as we shall see, buildings represent excellent opportunities to make this happen. Why is
this? Transactive systems can stimulate innovative services and products
with clear time and location value.
These can be used to create increasingly flexible and resilient distribution systems, and smart buildings
provide the potential to create platforms or transactive ecosystems to
enable this.

Metaheuristics
Metaheuristics are applied to I-knowit-when-I-see-it problems. They're
algorithms used to find answers to
problems when you have very little
to help you: you don't know beforehand what the optimal solution
looks like, you don't know how to go
about finding it in a principled way,
you have very little heuristic information to go on, and brute-force
search is out of the question because
the space is too large. But if you're
(continued on page 40)

Table of Contents for the Digital Edition of IEEE Electrification Magazine - December 2016