Page 55 - Energize May 2022

TECHNICAL

Energy storage microgrid controls away from top-down hierarchical approaches to a more distributed
A variety of different systems are now approach to automation and control. Distributed device-level intelligence, such as power
in use including Li-ion batteries and electronics embedded in smart inverters attached to solar PV and batteries, favours modular
their variations, flow or redox batteries, microgrids.
and compressed air systems. Energy Standardised designs mean a microgrid can be constructed, tested and deployed with
storage systems (ESS) include smart minimal special engineering and installation. In this instance, microgrid systems can be
controls which manage the state of built to include microgrid controls, ESS and switchgear in a single standard ISO container
the battery. Having the ability to store arrangement. These systems can be designed for modular growth. Engineering is handled at
energy onsite has a wide range of the manufacturing location and only onsite integration engineering would be required. The
benefits for C&I facilities. Acting as modular nature and containerised structure of modular microgrids make them more suitable
part of a UPS, energy storage can help for C&I applications than individually designed and constructed units. Figure 2 shows a
support resilience against a utility grid typical modular C&I microgrid.
outage, in coordination with backup
generators, CCHP and renewables. ESS Containerised construction
could maximise the value of renewable In addition to modular switchgear designs, pre-packaged management software includes
energy generation by saving excess pre-engineered AI-driven algorithms to support all important decision-making and control
energy for use when solar generators are applications, such as managing the grid connection, managing any DER in grid-connected
not producing electricity. Stored energy and island mode, and safety assurance. It can also include a variety of decisions and
can also be dispatched for peak demand actions to minimise cost and maximise sustainability, such as avoiding demand penalties,
management, helping reduce the amount tariff management, demand response participation and optimizing self-consumption of
of energy consumed from the utility renewables.
grid during periods of high energy cost.
Although capital intensive, energy storage Microgrid-as-a-service (MAAS)
is a good option to address load peaks. In the MAAS model the microgrid is owned and operated by a third party, which supplies
energy to the user at a rate based on consumption. The microgrid operator acts in parallel
Grid connection to the utility and may be located on or off site. This means that the operator owns the
The grid connection may be permanent, microgrid and is accountable for the capital investment and the delivery of predefined
or could allow islanding, depending on the outcomes that meet a customer’s goals for sustainability, reliability, resilience and cost-
type of microgrid chosen. Where there is a effectiveness.
permanent connection, the grid provides Microgrid-as-a service partners allow the customer to focus on the business and not
the main source of electricity. The grid the operation or management of the microgrid. MAAS delivers a fully managed, data-driven
may also be used as an alternative supply solution to help with power delivery requirements. Advanced data gathering from numerous
to the primary generation system. operational microgrid deployments improve decision making and proactive service.
The vast majority of challenges in MAAS have already been overcome. Improved service
Microgrid management system level agreements (SLAs) ensure optimal operation alongside promised levels of resiliency and
This is the most important component uptime. For example, advanced microgrid systems are truly connected in the sense that they
of a microgrid and has developed into a leverage data, machine learning and data analytics to proactively maintain optimal operating
complex system capable of a wide range of environments.
control functions.

Modular microgrids
Traditionally, microgrids have been custom
engineered, with every design being
unique and tailored for the specific facility.
This potentially makes design, installation
and operation time consuming and costly.
The maturing of the microgrid market
has created a new range of microgrid
solutions, based on standardised, pre-
packaged system components. These
building blocks, together with predefined
architectures, enable configured-to-order
microgrid systems.
Another important trend affecting Figure 2: Mounting of control units, ESS system and protection switchgear in a container simplifies
modular microgrids is the transition of construction and makes application easier (Microgrid knowledge)

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