Grid grief: Facing ‘voltage collapse conditions,’ PSE plans millions in investments on peninsula
Powering
the Peninsula, Part 1: Kitsap County’s power grid is becoming more
unreliable and stressed. How does it work, and how will PSE fix it?
Josh Farley
Kitsap Sun
GORST —
Kitsap Peninsula's electrical grid is growing more unreliable and
antiquated and will require tens of millions of dollars in upgrades in
the next decade. That includes proposals to construct power stations
west of Bremerton and add a battery-fed power storage system on
Bainbridge Island.
Research by
Puget Sound Energy, Kitsap County's power provider and the largest
utility in the state, shows it faces a host of challenges in response to
climate change to keep electricity flowing for its one million
customers.
The
peninsula's power grid either needs more electricity sources or
conservation from its customers if it is to avoid the risks of
blackouts, PSE found in one study, performed in 2018. The study also
found that eight of the company's Kitsap transmission lines "exceeded
their emergency limits" for reliability.
Further,
PSE also found local power generation will be necessary to keep the
grid operating in the future at peak times. Failure to act could cause
lines to carry too much load and cause power to go out.
"The
Kitsap Peninsula needs are so great the peninsula load would need to be
reduced by more than 30 percent in the near term to reduce all ...
thermal overload and voltage collapse conditions," the study states.
Thermal
overload is an overheating of power lines that, on a larger scale, is
akin to plugging too many electrical devices into a circuit at home. The
effect can damage the lines and cause low voltage, power outages, and
even the risk of fires, according to Dave Townsend, an electrical
engineer who worked as a transmission system planner for Puget Sound
Energy for three decades.
"Conservation
will still be a big part of PSE’s energy strategy in Kitsap County, but
it will not be enough to accommodate the increasing electrical loads of
the projected population growth and the increasing electrification of a
greener society over the next decade," Townsend said.
Townsend
is a consultant on a project to construct a biodiesel power plant, at
Ueland Tree Farm near Kitsap Lake, which could help take on some of the
power load. (While PSE has invited proposals to help generate power for
its grid, it is not involved in the project, and has not yet commented
publicly about it.)
Yet another project, this one proposed by New York-based Novis Renewables,
would build a bank of batteries off Bremerton's Sand Dollar
Road, totaling 125 megawatts. The energy storage facility, just north of
Gorst, could feed the electricity grid at peak use times, according to
documents filed with the Kitsap County Department of Community
Development.
Aging electrical grids are not unique to Kitsap and Washington. Some, like the century-plus high transmission lines, have led to devastating wildfires like those in California in 2018. But Kitsap County, being surrounded on nearly all sides by water, has a challenge most areas in the United States do not.
"The
geography doesn't help because it limits the options for bringing in
new transmission lines," said Daniel Kirschen, professor of electrical
and computer engineering at the University of Washington.
How Kitsap's power grid works
Kitsap residents from Olalla to Bainbridge Island rely on a network that begins in Gorst. High transmission lines owned by the Bonneville Power Administration bring electricity there, where it is dispersed throughout the peninsula on lines owned by Puget Sound Energy.
Bonneville
also has two massive bulk transformers in Gorst, each capable of
handling 230 kilovolts of power. They're aging: 46 and 57 years old,
respectively. The loss of either would result in widespread
outages. During that time it would "put PSE’s Kitsap load at risk of a
large outage or voltage collapse for the next major contingency during
peak winter conditions," PSE said in its study.
Other
than through the south end of Kitsap, the only other way to bring bulk
power here is via undersea cables near Vashon Island and the
Edmonds-Kingston ferry route. But those routes are old, undersized and
would be cost prohibitive to route power through, Townsend said.
Census records show close to 50,000 more people live in Kitsap since 2000,
placing increasing demands on an electricity grid of 28 substations and
18 transmission lines. More Kitsap residents are also
installing air-conditioning and, thanks the COVID-19 pandemic, working
from home and using more power throughout the day. To top it off, a
small but increasing number of drivers are purchasing all-electric
vehicles, placing further strain on Kitsap's power.
During
harsh winter months, Kitsap County relies on its electrical grid more
than other counties in Puget Sound because natural gas is less available
as a heating source here, Townsend pointed out.
So
Kitsap's electrical grid needs one of two things: a costly new set of
transmission lines into Kitsap, requiring construction and property
purchases, or the construction of a power plant on the peninsula to
generate its own power.
"There
are only two alternatives to supplying Kitsap County with this energy —
another bulk transmission line and generation from another county or
locally owned and controlled generation," he said.
Meanwhile,
PSE has another problem: the growth of renewable sources like wind and
solar power have nowhere near compensated for the closures
of heavy carbon emitters such as the Centralia Power Plant, where the
last coal-fired burner will power down in 2025. Puget Sound Energy still gets almost 50% of its power from coal and natural gas.
“We
are adding more to the grid in an effort to be more green, but we're
also mandating the closure of some sources of power,” said Lynn Eaton,
spokeswoman for Mason County Public Utilities District 3. “At the same
time we’re adding load, we’re reducing our ability to carry that load.”
Renewable sources
like wind and solar tend to be generated on the eastern side of the
state – there’s more sun, and fewer complaints about wind farms – so
costly transmission lines must be built to transport that power west,
which takes time.
And renewable sources aren't always generating power.
"But the sun doesn't always shine and the wind doesn't always blow," Kirschen said.
What
is certain is Puget Sound Energy will have to make investments to
divest its power sources, and that's going to come at a cost to
ratepayers. Earlier this year, the utility proposed to the Washington Utilities and Transportation Commission a nearly 13% increase in electric bills, starting in 2023, which would result in an average increase of $12 per month for customers.
'Resiliency' projects for Bainbridge, Seabeck coming
Kitsap's
needs go beyond its growth, however. The grid needs greater resiliency
in the face of storms and other possible outages. In the electricity
business, engineers measure a grid's reliability by what happens if one
of its main sources of power goes down. In Kitsap, there are three main
transmission lines that arrive at Gorst. If one goes down in the future,
there is concern over whether the other two could handle the load.
So
reliability has become Puget Sound Energy's focus around Kitsap. The
utility plans to make substantial upgrades in Seabeck and also install
the biggest bank of battery power in the history of the utility at the
Murden Cove substation on Bainbridge Island.
"For
both Seabeck and Kitsap County, needs have been identified and PSE is
comparing solution alternatives," PSE said in a statement to the Kitsap
Sun. "In Seabeck, a smaller circuit capacity and reliability need was
identified and in Kitsap County PSE has identified capacity, aging
infrastructure and operational flexibility need."
Puget
Sound Energy did not confirm the power plant project at Ueland, saying
it is still "in the process of studying the solutions."
"Once
that is complete we will be working towards the appropriate solution
and it may or may not include proposals necessary to reinforce the
grid," PSE said in a statement.
On
Bainbridge, Puget Sound Energy plans to build a battery facility at its
Murden Cove substation that will provide 3.3 megawatts of power,
charging those batteries during low demand and using them during peak
times. The utility is also installing new lines and replacing old
equipment in the island's south end to increase reliability to go with a
previously announced project to connect transmission lines between two
substations that will create a loop.
Meanwhile,
PSE said in a statement to the Kitsap Sun it is still working to
identify which solutions fit best for the peninsula.
"No
specific project has been launched because we are in the process of
studying the solutions," PSE spokesman Andrew Padula said. "Once that is
complete we will be working towards the appropriate solution and it may
or may not include proposals necessary to reinforce the grid."
Coming Monday: Ueland Tree Farm plans to build a biodiesel power plant just west of Bremerton.
