LOW-CARBON DRILLING SOLUTIONS
COSL Drilling’s Energy Control System displays fuel
consumption and emissions data on a dashboard. As it
is connected to the rig’s control system, the software can
automatically act upon its own advisory without any input
from the rig crew, but users can also override the system in
case of any unforeseen circumstances. The system is now
deployed on all three of COSL Drilling’s contracted rigs in the
North Sea.

reported fuel consumption as low as 7.6 tons/day. CO2 and NOx
emissions have also fallen by around 50% on the two rigs since
installation. “We were almost shocked to see how much energy we were
consuming in normal drilling operations,” Mr Tollefsen said.

“Even when we first developed this, we thought we would need
all of this energy, but in a normal drilling operation, the actual
requirements can fall so low that they’re well within the capac-
ity of one generator. On average, we can run two or three, but
sometimes we’re down to one generator. That’s almost unheard
of in the industry because you always assume you need some
additional reserves.”
COSL Drilling also installed the system on the COSL Pioneer,
operating on the UK Continental Shelf, in December 2021. In the
three months following installation, the semisubmersible saved
904 tons of fuel compared with the previous three months. This
fuel reduction equated to approximately 2.85 tons of CO2 saved.

The Energy Control System is currently running on all three of
COSL Drilling’s contracted rigs in the North Sea. In March 2022,
the COSL Pioneer began work under a new contract with Ithaca
Energy that is expected to last until Q2 2024. The COSL Promoter
is slated to work for Equinor through Q1 2024, while the COSL
Innovator began a new contract with CNOOC Europe in April
2022. While the Energy Control System was developed for use on
COSL Drilling’s North Sea rigs, Mr Tollefsen said the company is
looking to expand its deployment in other regions, as well.

Engine management
Valaris is looking to enhanced power management systems as
a low-carbon offering in its technology portfolio. In October 2021,
the VALARIS DS-12 drillship became the first vessel in the world
to receive the ABS Enhanced Electrical System Notation EHS-E.

Valaris upgraded the rig’s electrical system to secure the notation,
which recognizes improvements in power system redundancy
16 and reliability. The enhanced system enables the rig to safely
operate with as few as two generators online, thereby reducing
emissions. VALARIS DS-12 worked for a major operator in Angola during
Q4 2021 and Q1 2022 and is expected to be working for the operator
offshore Mauritania and Senegal through the remainder of 2022.

During the Angola campaign, Valaris realized a 5% reduction in
fuel consumption and approximately 600-MT reduction in CO2
emissions compared with the pre-upgrade configuration, which
required a minimum of three generators online. Mr Luca noted
that the mild environmental conditions found offshore Angola
made it an ideal proving ground for this new technology.

The company hopes to install the enhanced power manage-
ment system on more of its floater fleet in the future, but further
deployment will also depend on customer demand. “It’s an invest-
ment to take the rig out of operation for a period of time and install
this system, so we hope to find the right partners who are willing
to invest in that enhancement for the rig, thereby making their
own operations more carbon efficient.”
The engine optimization system is one solution within the
Valaris portfolio of options to reduce GHG emissions. For a
fleetwide view and tracking of these emissions, the company
leverages the Valaris Intelligence Platform (VIP), a monitoring
program that aggregates and displays fuel consumption and GHG
emissions for each monitored rig in its fleet.

The program helps establish a baseline of fuel consumption
and emissions by rig and engine type, which can then help the
company quantify the impact of the various solutions it chooses
to deploy across its fleet.

While the VIP system monitors mission-critical rig equipment,
it also provides dashboards for fuel consumption, CO2, NOx and
SOx emissions over time. Understanding power requirements at
the rig site and comparing against the amount of power available
from the rig power plant enables the technical team to optimize
the gap between the two, based on the operating conditions at
any given time.

The VIP system is currently available on more than half of
active Valaris rigs and is on track for deployment to the remain-
der of the active fleet by year-end.

“VIP is really about streaming systems data into an aggregator
and analytic solution to tell us how our rigs are being run. This
enables us to better monitor our systems and our power plants.

From there, we can visualize the loading of a particular engine in
real time, optimize the loads on the engine, optimize the fuel and
determine where we can reduce emissions,” Mr Luca said.

In addition to the VIP system and enhanced power manage-
ment system, Valaris has installed selective catalytic reduction
(SCR) systems on four drillships – VALARIS DS-15, DS-16, DS-17
and DS-18 – and one jackup, VALARIS 123. SCR is an emissions
control technology that filters out certain potentially harmful
elements from the engine exhaust system. An additive is added
to the exhaust fumes, initiating a chemical reaction that converts
NOx into nitrogen, water and tiny amounts of CO2. While NOx
emissions data from the four drillships are not yet available,
Valaris has reported a 90% reduction in NOx from the VALARIS
123 jackup since the SCR installation.

M AY/J U N E 202 2 • D R I L L I N G C O N T R AC T O R