Operational emissions at oil and gas facilities can be low hanging fruit for companies wanting to lower their carbon footprint, with rig electrification and the use of renewable energy increasingly transforming offshore power generation.
With the increased focus from regulators, investors, and the public, there is a need for the oil and gas industry to operate sustainably if it wants to remain part of the energy mix. Offshore oil and gas production emits large amounts of greenhouse gases, during exploration and extraction, processing and refining, as well as when the fuel is ultimately burned.
At current rates, lifecycle emissions from offshore oil and gas are estimated to reach more than eight billion tonnes of carbon dioxide equivalent by 2050. In August last year, Norwegian-owned Equinor opened its Hywind Tampen wind farm, which is the world’s largest floating offshore wind farm and is powering the Gullfaks and Snorre oil and gas platforms in the North Sea.
These oil and gas facilities were the first in the world to receive power from offshore wind, which is expected to cover about 35 per cent of annual electricity consumption across five individual platforms.
Hywind Tampen is about 140 kilometres from shore in water depth between 260 and 300 metres and consists of 11 wind turbines with a system capacity of 88 megawatts. Equinor has also partnered with Australian company Oceanex to pursue floating offshore wind opportunities in New South Wales, including the Novocastrian offshore wind farm in the Hunter, as well as with Nexsphere to progress the Bass offshore wind energy project in the Bass Strait.
Thomas Hansen, Senior Director for Offshore Wind Australia at Equinor, said Hywind Tampen was making a significant contribution to further developing the technology at scale and reducing the future cost of floating offshore wind in a growing global market, including Australia.
He said: “Hywind Tampen was completed in five years, with 60 per cent of the contract values in the project awarded to Norwegian suppliers. “This has contributed to new activity, green jobs, local spinoffs and technology development for future floating offshore wind projects in a growing industry. “Equinor is bringing this experience to Australia, as we mature floating offshore wind projects in NSW with our local partner.”
With Hywind Tampen operational, Equinor is now operating nearly half of the world’s offshore floating wind capacity. Last year Equinor also successfully electrified its offshore facilities at the Gina Krog project, also in the North Sea, as part of its wider transition to lower-emission production.
Due to electrification, among other initiatives, Equinor’s Johan Sverdrup field now has carbon emissions of just 0.67 kilograms per barrel, compared with an average of nine kilograms. Most of the measures implemented are related to energy efficiency, as the electrification of plants already in operation requires major rebuilding and is only economical for plants with long lifespans.
The process of electrification generally involves laying cables from a clean power grid on land to the areas where replacing gas turbines is most effective. United Arab Emirates’ state oil company ADNOC is also in the process of electrifying its offshore operations by connecting to a clean onshore power network through subsea transmission cables, with the project aiming for commercial operation in 2025.
Costing US$3.8 billion, the project will see clean energy sent from two onshore locations to two islands via subsea cables, both more than 130 kilometres long, from where it will be distributed to other offshore installations.
The power will replace electricity currently generated from gas turbine generations and will reduce ADNOC’s offshore carbon footprint by up to 50 per cent. According to the company, it implemented more than 40 sustainability projects in 2022, as well as using grid-imported power, that collectively reduced emissions by 5.4 million tonnes of carbon dioxide equivalent across its operations.
Another example of renewable power generation is Woodside Energy’s proposed 500-megawatt solar farm near Karratha, which would supply renewable energy to industrial customers on the Burrup Peninsula including Woodside’s Pluto LNG export facility. In December, Western Australia’s Regional Joint Development Assessment Panel gave planning approval to Woodside for the $300-million project, which will see an initial 100-megawatt photovoltaic facility developed that can then be expanded in stages up to full capacity.
The project also includes up to 2,000 megawatt-hours of battery storage, however this will need separate development approval. Woodside has estimated that every 100 megawatts of renewable electricity supplied to customers through the North West Interconnected System (NWIS) is expected to reduce carbon emissions by 100,000 tonnes a year, as well as reducing emissions of other pollutants such as nitrogen and sulphur oxides.
The solar farm is proposed to be built on a 975-hectare site in the Maitland Strategic Industrial Area, about 15 kilometres southwest of Karrath. Woodside entered into a bilaterial Indigenous Land Use Agreement and a modern benefits-sharing and relationship agreement in late 2022 with the Ngarluma Aboriginal Corporation for the areas that come under the project.
