Handbook of Energy Storage for Transmission or ... - W2agz.com

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T&D SYSTEM ENERGY STORAGE SYSTEM APPLICATIONS
standby power losses associated with maintaining the PCS in a “hot” condition. This
application is functionally equivalent to the 6MW NAS installations at TEPCO’s Ohito
and Tsunashima substations in Japan. Where appropriate for the user’s needs, grid
interactive power electronics may be incorporated so that the same energy storage system
can be utilized for both load leveling and AGC. The economics of such a case are
discussed in Section 4.
2. 10MW distribution substation for up to 30 seconds power disturbance mitigation
(utilizing 40 NAS PQ Modules): Growth in businesses relying on automated processes
and digital transactions that are sensitive to power disturbances has created a demand for
equipment to mitigate events such as voltage sags. In the future, the automation of T&D
systems in concert with utility deregulation is expected to increase demand for equipment
to maintain grid stability. DSTATCOM-type power conversion and grid interface
systems utilizing energy storage provide a static alternative to rotary systems. Such
applications also require both the PCS and energy storage media to be capable of full
power within a few milliseconds. This application provides the grid support functions
accomplished by D-SMES, plus sufficient energy to address 99+% of power disturbances
and bridge to fast starting generation options. Where appropriate for the user’s needs,
this application and the previous application (load leveling) may be combined. The
economics of such a case are also discussed in Section 4.
3. 26MW transmission substation installation for 1 hour AGC (utilizing 200 NAS PQ
Modules): AGC equipment contributes to controlling power interchange and
interconnection frequency regulation between grid control areas by automatically
adjusting the supply of power. Energy storage systems comprised of fast response energy
storage media and grid interactive power electronic interfaces can contribute to enhanced
grid stability. This application requires full power within a cycle for up to one hour
equivalent discharge duration during periods of potential grid instability. It is
functionally similar to the 40MW Golden Valley Electric Association Battery Energy
Storage System at Fairbanks, Alaska, which is designed for 15 minutes grid support.
Economic comparisons with the GVEA Battery Energy Storage System (BESS) are
provided in Section 4.
4. 2MW energy storage stabilizing a 20MW wind farm (utilizing 40 NAS PS Modules):
The intermittent nature of wind resources inhibits economic utilization within a power
marketing framework. That is, economic risks associated with uncertainties in wind
patterns may limit the commitment to provide firm power during periods of peak demand
to a small fraction of rated wind generation power. Energy storage systems can stabilize
wind generation; however, identifying an economically viable configuration entails
assessment of site specific factors including diurnal and seasonal variations in the wind
resource, the wind farm interface with the utility grid, the prevailing electricity rate
structure and viable business models. The application described herein is based on data
from a wind turbine site. While detailed characterization of the wind resource is beyond
of the scope of this Handbook, key elements of the assessment are insightful. These
include:
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