Electrification
is the most practical solution for decarbonization, especially as renewable
generating capacity increases and momentum to electrify vessels, including
FPSOs, continues to build. However, the industry still faces headwinds,
including high upfront costs, a lack of supporting infrastructure and properly trained
personnel, and gaps in standards.
The marine
and offshore sectors have an important role to play in driving a successful
energy transition. In recent years, significant progress has been made by operators
and original equipment manufacturers (OEMs) to decarbonize operations through engine
efficiency improvements, the use of alternative fuels and alternative energy, Fig.
1. Electrification initiatives also have expanded across many vessel types,
including passenger ferries, tugboats, Offshore Support Vessels (OSVs)—which
can include Platform Supply Vessels (PSVs)—Crew Transfer Vessels (CTVs) and
drilling rigs.
ABS has supported
industry electrification efforts by publishing important guidelines and requirements
for offshore energy generation and distribution, battery energy storage systems,
fuel cells and hybrid electrical power systems. We are now taking the next step
on our roadmap by exploring how electrification technologies and concepts can
be applied to accelerate decarbonization of Floating, Production, Storage and
Offloading (FPSO) vessels.
DECARBONIZING
OFFSHORE OIL AND GAS PRODUCTION
FPSOs have fundamentally
transformed offshore oil and gas production over the last two to three decades,
by allowing operators to exploit reserves in deep and ultra-deep waters and
highly remote locations. Their flexibility and adaptability overcome many of
the limitations of traditional fixed structures, opening up offshore field
development opportunities across the globe that were once considered
economically unviable.
While operators,
engineering firms, and OEMs have made strides to reduce the carbon footprint of
modern FPSOs in recent years, pressure to curb greenhouse gas (GHG) emissions continues
to mount. The FPSO sector will be responsible for an estimated 38 million tons
of CO2 emissions in 2023 and nearly 50 million tons by 2030, unless
steps are taken to curb Scope 1, 2 and 3 emissions.1
In certain
regions of the world—such as the North Sea—carbon intensity per barrel of oil
produced has become a determining factor in whether field development projects
reach final investment decision (FID). It is plausible that this will
eventually be the case in other offshore producing regions of the globe,
including the Gulf of Mexico (GOM) and South America.
FPSO
ELECTRIFICATION
Among all
options, electrification represents the most practical and feasible path
forward when it comes to FPSO decarbonization.
Several
FPSOs under development have embraced electrification strategies in recent
years. However, the sheer complexity and power demand of these facilities
(typically anywhere from 80–150 MW), along with substantial requirements for
process heat, make electrification a much more challenging task when compared
to smaller marine vessels.
The
majority of emissions generated on an FPSO originate from gas turbine
generators (GTGs), which provide electricity to various onboard operations. In
many cases, waste heat from the GTGs also serves as a source of heat for
processing systems. Diesel generators are often used for auxiliary power and
for backup in emergency (i.e., black-out) situations. The first step in
decarbonization is using the GTGs more and diesel generators less, with the
goal to reduce the number and size of the diesel generators.
Significant
emissions reductions are possible by augmenting power generation from GTGs with
alternate sources, such as offshore wind or power from shore, if the FPSO is
within a reasonable distance of land. Doing so allows for the use of fewer GTGs
with rated capacities that are optimized for the electrical requirements of the
facility, resulting in a power plant with higher fuel efficiency.
Even marginal increases in efficiency can
have a substantial impact on the facility’s carbon footprint. For instance, a
1% fuel efficiency increase of an FPSO power plant utilizing four 30-MW
aeroderivative GTs to meet an 80-MW power requirement can result in the
avoidance of around 6,500 metric tons of CO2 per
year.2
Harnessing clean
energy sources also introduces the possibility of implementing new power plant redundancy
schemes, by eliminating the requirement for diesel generators. The intermittent
nature of renewables does mean this would likely require the addition of an energy
storage system (ESS)—such as lithium-ion batteries, supercapacitors, flywheels
or others—to ensure continuous power. Hybrid (i.e., diesel/gas-electric) power systems
with lithium-ion batteries have been applied successfully on several types of
vessels, including PSVs, LNG carriers, offshore drilling rigs and more.
Similar
concepts are being implemented that feature batteries integrated within the
column of offshore floating or fixed wind turbines. In such cases, multiple
floating units can be tied together to form an offshore microgrid that is capable
of supplying clean, stable power to one or more offshore assets, thereby
reducing the duty on conventional generating assets. The wind units also could
be equipped with necessary systems to enable smaller electric or hybrid vessels
to charge their batteries and reduce the number of trips to shore.
Hybrid power
concepts already have shown promise when applied to smaller assets, like
drilling rigs. However, given the extremely demanding requirements for
reliability and production uptime on FPSOs, more work needs to be done to
define requirements and develop guidelines that minimize the risk of their
application.
ABS
ELECTRIFICATION WORKSHOP
ABS is
committed to supporting the offshore industry’s electrification initiatives and
has published several requirements and guides for energy storage systems,
hybrid power systems, offshore substations and electrical services, such as offshore
charging systems, power shore connections and more.
Recently,
we held an offshore electrification workshop attended by an international forum
of oil companies, designers, equipment suppliers and many more industry leaders,
to better understand the challenges associated with FPSO electrification and
answer important questions, such as:
The
workshop proved to be a productive event. Participants were in broad agreement
on the need to advance technologies for offshore electrification, including
connections for offshore and onshore renewable energy sources, ESS and charging
systems. Multiple respondents also cited nuclear as a technology that should be
considered for offshore power generation.
Nearly
two-thirds of respondents cited financial constraints and obtaining a reliable
electrical supply as the primary hurdles to offshore electrification. Other
notable responses were a lack of a standardized interface for offshore power
and low infrastructure readiness, as well as performance and space constraints.
More than
half of workshop participants said that the source of power generation should
not fall within the regulatory scope, if it is located outside of the vessel.
However, the overwhelming majority believed that the interface to the external
power supply should be included. Responses on potential failure points were
mixed, with several participants citing high-voltage transmission lines and
subsea cables. Personnel training also emerged as a concern.
SUSTAINING MOMENTUM
Achieving
carbon neutrality in the marine and offshore sectors will require contributions
from a broad range of technologies. While the use of alternative fuels and
carbon capture, utilization and storage (CCUS) has an important role to play,
electrification is the most practical solution for decarbonization (Fig. 2),
and this will likely remain the case, as renewable generating capacity increases.
Overall, momentum
to electrify vessels, including FPSOs, continues to build. However, the
industry still faces headwinds, including high upfront costs, a lack of
supporting infrastructure and properly trained personnel and gaps in technical
and safety standards. These standards are a task that ABS is committed to solving
by working closely with stakeholders, to ensure that risks of technology
implementation are adequately understood and addressed—including the development
of rules and requirements that help to better support FPSO electrification. WO
REFERENCES
MATTHEW TREMBLAY serves as ABS senior vice president of Global Offshore Markets, based at ABS Corporate Headquarters in Houston. In his current role, Mr. Tremblay holds the global responsibility for strategic planning and client development within the offshore market sector. Throughout his 27-year tenure at ABS, Mr. Tremblay has served in various engineering and leadership positions throughout the United States and Asia, including Pacific Division Vice President of Operations, based in Singapore, and Vice President of Engineering for the ABS Americas Division. Mr. Tremblay graduated from the Massachusetts Maritime Academy with a bachelor's degree in marine engineering. He is also a member of the American Society of Naval Architects and Marine Engineers (SNAME).