Electrification is plan A, but what is plan B if you can’t electrify your asset?

In the quest to decarbonise offshore energy assets, where power generation accounts for almost 80% of the UK Continental Shelf (UKCS) emissions, electrification stands as the primary strategy.

Significant advancements are being made to floating offshore wind technology. By 2030 it is estimated offshore wind will provide almost 7% of the EU’s electricity, and almost 91% of this contribution will be supplied from the North Sea.

However, electrification is not always viable due to factors such as asset age, location, available space on the platform, or prohibitive costs.

So, what else can be implemented to reduce emissions from power generation?

Power management through correctly sizing turbines for current operations and downsizing is an option, but replacing what is already installed is expensive.

Optimisation and digitalisation present immediate, albeit incremental, benefits. Digital power management systems can enhance efficiency by balancing power needs in real-time, aligning energy production with actual demand.

Whilst these incremental gains move assets towards decarbonisation, a more substantial shift involves transitioning to low carbon fuel solutions. A phased approach to replacing diesel with bio-diesel can yield significant emissions reductions. Furthermore, retrofitting existing fuel gas or dual-fuel turbines, to operate on alternative e-fuels presents a promising avenue.

E-fuels come in many forms such as methanol, diesel and kerosene but the starting point is always the combination of green hydrogen and captured carbon dioxide. The process involves taking hydrogen gas and converting it into a liquid fuel, which removes one of the largest challenges of hydrogen as a fuel – its low volumetric energy density.

Biggest impact with the newest approach

Retrofitting existing equipment and running it on alternative fuels represents the biggest impact where electrification isn’t feasible. This not only aids in reducing emissions but also extends the life and utility of current assets.

The adoption of e-methanol (produced from renewable electricity and captured CO2 from a coal power plant) as a fuel over natural gas would provide an emissions reduction of approximately 74%.

At Net Zero Technology Centre (NZTC) we’re proving it’s feasible and scalable. In a world-first pilot, along with Siemens Energy we successfully demonstrated a green methanol-powered aero-derived gas turbine; the SGT-A20, first used industrially in 1964. Minimal retrofitting was done on the turbine which supports the analysis that we’ve done up until now, which shows there are no real technical barriers to conversion to use it offshore. The modifications were also still compatible with other fuels, which increases the operational flexibility of the turbine.

However, as this is a new approach and the technology is still nascent, it introduces challenges such as ensuring safe storage and handling, managing logistics, cost of e-fuels and securing a steady supply chain.

Floating production storage and offloading or FPSOs are best placed to address many of these issues due to the existing storage tanks, which are already sized at the capacities needed.  For fixed assets, especially those powered by low-cost produced natural gas, this can be more difficult. However, retrofittable subsea liquid storage systems are being developed for offshore platforms, and the large uptake of synthetic fuels from other industries means the supply chains are forming to produce green fuels at scale. In terms of synthetic e-kerosene, adoption has already been vastly integrated into the aviation industry.

For green methanol, the marine industry is driving the global production, with over 220 large methanol compatible ships on order. The global production of bio-methanol and e-methanol is set to increase from 0.8 Million tonnes in 2024, to an estimated 19.7 million tonnes by 2029, from over 130 projects currently underway. None of which, are in the UK.

Green ammonia is also a promising alternative fuel due to the feedstock availability and the low feedstock volume requirements.

The notable differentiator between ammonia and methanol is the storage conditions. Methanol is a liquid at ambient pressure and temperature whereas ammonia needs to be either refrigerated past its boiling point of around -33°C or pressurized to remain in a liquid state. This makes the substance more challenging to handle, although there is extensive onshore experience in handling and transportation of ammonia via its use in the fertilizer industry.

Whilst ammonia is a completely carbon-free fuel in comparison to carbon-neutral methanol, ammonia is significantly more damaging to the environment on NOx emissions. Although this greenhouse gas has a shorter life expectancy in the atmosphere, in comparison to CO2, its global warming potential over a twenty-year period can be up to three hundred times more potent. NOx gases in the atmosphere also contribute to respiratory issues in humans, as well as smog and acid rain.

Boosting the adoption of alternative fuels requires tackling supply challenges to achieve cost competitiveness with conventional fuels. Transporting methanol is similar to current fuel logistics, yet establishing green methanol production in the UK is crucial for market competition within Europe.

In an ideal world, Plan A would be electrification, however, a robust Plan B that combines digital optimisation, equipment modification and alternative fuels will still help in achieving emission reduction targets.

NZTC’s Horizon Scanning service provides regular bespoke insights on emerging technologies, industry trends, global projects and policy. Short and long-term profile scanning enables organisations to stay ahead, future-proof their business and support their diversification strategy by providing a clear understanding of the technology and global landscape.