POWER April 2016 - 62

OPERATIONS & MAINTENANCE
Preparing for a Heavy Spring Outage Season
We were headed into one of our toughest
spring outage seasons when we decided to
apply a system view, through a Brittleness
Assessment / Resilience Design workshop.
Resilience engineering was a new concept
to this group, so we began with the basics
of what brittle and resilient looked like
along with a little bit of systems science. In
addition to Calpine, I've held similar workshops
with an original equipment manufacturer
(OEM) field service group.
First, establish a common understanding
between planning and all resource groups
(people, tools, and parts) of the situation
and plans.
Second, create a system view (typically,
on a whiteboard) that shows outages
and resources (people, tools, parts) along
with constraints and interdependencies
(Figure 1).
Third, probe the following:
to arrive and depart just in time.
■ What have we assumed (especially in planning)?
We found that different groups
had different assumptions about load.
We found assumptions that all outages
would complete on time even though a
significant percentage of outages historically
ran long.
■ Which outages are double-constrained
(with hard start and end dates)? We
found four double-constrained outages:
hard start and finish dates; constraints
caused by turning parts from one unit,
and repairing them, to go into another
unit; or regulator constraints to finish
outages at one plant before bringing the
other down.
■ Which outages are tightly coupled or interdependent?
Tight coupling means effects
spread quickly, leaving limited slack or buffer.
We found cases of no buffer for outages
running long; people and parts were timed
tor yield points to give us a chance to adapt
and reconfigure so we can handle additional
load without failing. Different conditions can
bring us close to a yield point, such as a certain
level of deployment (for example, 85%
deployed is sustainable, but more than that
may not be); three or more significant issues
on a project; piling up stressors such as foul
weather, a holiday, and change-out of people;
or novel or complex work.
There are signs that indicate we are approaching
a yield point. One is that people
62
■ Which outage, if it ran long, would be
most disruptive and cause the most ripple
effects? We identified one outage that
was clearly the most complex and with
the highest resource requirements.
■ Where are potential single-point failures
(such as key people or critical tools for
which there is no backup)? We found turn
times for critical tools for which there
was no backup, yet work was expected
to go perfectly each time.
■ Who is most likely to become stretched to
the point that they can't keep up?
■ What don't we know yet? Identify and
bound uncertainties.
The first time you hold such a workshop,
all that may come out of it is the ability
to notice brittleness. This is not a panacea,
but it's a first step toward becoming more
resilient. We can safely say we went into this
begin acting differently. We can look for
signs that the mood or situation has changed:
progress stalls, schedule slips, people don't
return calls or emails, or people are irritable.
What signs have you noticed when approaching
a yield point? Who is in a good
position to monitor for change? Sometimes
when you're sick, it's hard to decide when to
call the doctor. Similarly, people off site may
be in a better position to notice changes at a
big picture level while people on site are immersed
in regaining control.
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outage season better prepared. Early on, one
outage with a hard end date ran into a significant
problem, which led to outage extension
with significant downstream impacts.
The outage season was tough-despite the
workshop. Such are the challenges in a resource-constrained
environment.
At the OEM site, actions taken after a
Brittleness Assessment / Resilience Design
workshop included negotiating 24/7 engineering
support; creating a special team to
stay in close touch with outages, monitor
risk level, and remove obstacles; and bringing
in a highly experienced retiree to support
a team that was stretched the thinnest.
We've tended to hold these workshops
late-roughly a month prior to outage season-which
limited our ability to respond.
Ideally, workshops should be held several
months prior to outage season to allow time
to plan for, design, and implement strategies
and tactics to increase resilience.
Principle 3: A System View Is
Necessary
A system view of work simply means stepping
back and looking at the big picture from
a level that makes sense-a power plant, a
fleet of power plants, or a set of outages-
considering that components within a complex
system have interdependencies. We have
a natural tendency to attempt to simplify systems,
focusing on individual components (X is
broken, fix it!). This can cause us to miss the
more nuanced influences related to system inPOWER
| April 2016
1. Get a system view. Whiteboards can help to develop a system view of an outage
before developing a formal plan. Courtesy: Calpine
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POWER April 2016

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