How floating wind micro-grids power oil and gas platforms
Knowledge of the micro-grid
When oil and gas companies are looking for microgrids to power their offshore platforms, offshore wind has generally not been the technology of choice.
Traditionally, oil and gas installations have used gas turbine generators to generate the electrical power needed to run their drilling operations, which require several hundred megawatts for heating, pumping, and processing. Many of these operations are also gas producers. Gas is readily available, so it’s an easy choice.
Industry sometimes uses solar energy. For example, ABB plans to install a solar and storage micro-grid for a platform operated by Australia’s largest independent oil and gas company to replace existing gas turbine generators.
A few pilot wind farm projects have been created, but they are all connected to land networks.
Odfjell Oceanwind plans to change all that with its WindGrid technology for microgrids. These are mobile offshore wind units, of 11 MW each, which supply the micro-grids supplying the oil and gas platforms.
Odfjell is currently focused on leasing units in the North Sea, particularly in Norway, which has ambitious targets for reducing carbon dioxide emissions. The region also has high carbon taxes and excellent wind all year round, said Per Lund, CEO of Oddjell Oceanwind, which is based in Norway and develops, owns and operates floating mobile offshore wind units for micro -networks.
The savings outweigh the costs
In Norway, being carbon intensive is expensive because of the fees and taxes levied on emitters. The sum of the national carbon dioxide charge and the European Union’s carbon reduction charge is now over $ 100 (US dollars) per tonne of carbon dioxide, he said. The Norwegian government has proposed to increase this figure to $ 220 (US dollars) per tonne by 2030. The goal is to reduce emissions by 55% by 2030.
“The total monetary savings from saved fuel and taxes normally outweigh the additional cost of rental wind turbines,” Lund said.
The company says its technology reduces carbon dioxide emissions by 70% compared to what conventional fossil fuel generators emit. This is double the reduction in emissions provided by conventional wind farms, as there is more offshore wind to harvest. This statistic was recently confirmed by an independent verification review conducted by DNV, an accredited certification body based in Norway that certifies companies’ compliance with third party standards.
“As the owner and operator of large floating assets ourselves, through Odfjell Drilling, we fully understand the importance of such a radical shift in energy management philosophies,” said Lund. It was important to the company that a recognized third party verified its technology so that customers could trust the company’s products, he added.
Wind turbines are the best option for serving offshore platforms because the wind is easy to harvest from the ocean, Lund said.
Disadvantages of other options
“We looked at the waves, the ocean current and the sun, but they all have their particular challenges in rough waters like the North Sea,” Lund said. Offshore wind resources are better than onshore and coastal wind resources, he added. “Another key to getting the most out of wind power is that our WindGrid solution gives you enough grid stability to shut down gas turbine generators during times of wind power production. “
Oddjell Oceanwind technology combines energy storage, grid converters and floating wind turbines to enable the shutdown of offshore gas turbine generators during peak wind power production. Offshore wind turbines provide power to oil and gas platforms used for drilling, processing and exporting oil and gas. Odfjell’s sister company, Odfjell Drilling, has helped develop technology for its fleet of mobile offshore drilling units.
Solar is generally less attractive for offshore drilling operations because it requires large areas.
“For offshore installations in harsh environments, these areas are rare and very expensive. Solar energy is only used to a very small extent, ”Lund said.
The typical micro-grid on a platform includes two or more gas turbine generators. On the platform are energy-consuming equipment, including pumps, compressors, heating and ventilation, Lund said. Microgrids are generally located several hundred kilometers from the shore. Microgrids can be fixed to the ocean floor or floating, and sometimes many facilities are connected in a single network.
“Basically, they’re big oil and gas processing plants in the ocean, often with hundreds of people moving to and from helicopters,” Lund said.
The company’s business model is to own and operate the floating wind turbines, and lease them to customers who can pay by the day or by the kWh. Lund said leasing is more attractive to customers because they only need the units for five to 15 years before the oil and gas facility is taken out of service.
“In many ways our rental model is energy as a service,” he said. Odfjell prefers to customize the configuration for each customer to maximize the value proposition, he added.
Not just for oil and gas platforms
Floating wind turbines are not only suitable for oil and gas rigs, but also for any application with high energy requirements and close to deep water resources and strong wind. This could include island communities and large offshore fish farms.
Offshore wind turbines produce more wind power and require less space than solar power. But they are also attractive because they are less likely to conflict with fisheries in offshore areas, compared to onshore and coastal wind installations.
“Our main potential conflict of interest is fishing, so we try to choose places that are of less interest to fishermen. Apart from that, we have to be careful not to drop our anchors and moor in the corals of the seabed and avoid bird migration routes, ”Lund said.
By leasing its wind turbines to microgrid users, the company aims to help reduce carbon emissions from the oil and gas industry in Norway and around the world. Floating wind turbines will allow the oil and gas industry to move “green” faster and more cheaply than with other technologies, including onshore wind power, Lund said.
This article originally appeared on Microgrid Knowledge. Reproduced here with permission