Can wind really work for oil, and vice versa? This was the challenge put before the industry at the Offshore Technology Conference in Houston (6-10 May 2019). Here, project director, Johan Sandberg, explains the genesis of idea of wind-powered water injection for offshore fields, and how the idea has edged towards a commercial reality.
“We should not be looking back but forward, we should develop a vision for the future - from now until 2050.” This was the challenging brief given to me and my colleagues by then-President and CEO of DNV GL, Henrik Madsen. The occasion was a planning meeting in early 2013 for events and activities to mark DNV GL’s 150th anniversary celebrations in 2014.
That anniversary will be remembered for many things – roundtable discussions with world experts on sustainability; the barge moored on the Oslo fjord at DNV GL’s Høvik campus that housed the celebrations enjoyed by thousands of colleagues and customers, and above all, the ambitious projects and initiatives that were kickstarted.
For me, 2014 was the start of a personal journey, taken together with many expert colleagues, customers and researchers, that today has resulted in a tantalizing lab-tested and fully documented opportunity for the industry to consider. Wind-Powered Water Injection – or ‘WIN WIN’, as we have dubbed it.
Why floating wind?
It was clear to us from the start that the focal point of this vision work should be floating offshore wind. Firstly, the ‘fit’ between DNV GL and offshore wind is a perfect match. It is an industry that encapsulates everything about us; our heritage from the ocean and maritime/shipping, offshore, renewable energy, power systems, and risk and sustainability. With offshore wind we combine not only our decades of offshore technical know-how, but also our extensive and growing expertise in wind power, HVDC, offshore structures, maritime logistics and wind turbine technology.
Why floating wind? Well, because we realised the need to bring offshore wind into deep water for the long-term success of the industry. While we knew, in 2014, it was immature technology its necessity had been brought into sharp relief by the effects of the tsunami following the Tōhoku earthquake in 2011 off the coast of Japan. In the wake of the tsunami and the destruction of the Fukushima nuclear plant, Japan was wrestling with both a power crisis, following its decision to shut down some 40 nuclear reactors, and a major challenge to rebuild and modernize its fishing fleet, which had also been devasted by the giant wave.
A grand vision for Japan ... and the world
A renewably-powered future for Japan faced some major obstacles. Japan’s islands are crowded, limiting the potential for solar parks and onshore wind. Offshore, it has marvellous wind resources, but challenging water depths providing an extraordinary potential for floating offshore wind. Could it be possible, we wondered, for Japan to scale up this technology in just three decades?
If that is going to happen at all, we thought, then it should happen in three broad phases of development:
- 2015-2025: Catalyst market - driving down costs and proving reliability requires a ‘starter’ market where floating wind turbines are the cheapest and best option. Paradoxically, we found that it is offshore oil production which offers most commercial potential for a range of activities to be powered by wind. Better still, we found that water injection is highly compatible with a fluctuating power supply. If offshore Oil & Gas would start using floating wind it would kick start the technical development.
- 2025-2035: Grid balance and energy storage – building floating wind at GW-scale, accompanied by offshore mega scale energy storage options, like pumped storage in enormous bladders on the seabed, compressed air, or even green hydrogen (via electrolysis), to provide reliable “base load” power and inertia to the grid.
- 2035-2050: Integration – in this final phase, the costs of floating wind will have been reduced to a level where it is significant part of energy mix and integrated with other industries like fishing and aquaculture. In this, final vision, offshore wind acts as the backbone of an ocean space strategy where you both protect marine life (with no bottom trawling owning to multiple mooring lines for floating wind) but also sustainably harness marine resources through controlled aquaculture and fixed gear fishing – with the fishing vessels doubling up as offshore services vessels for the wind farms.
The vision is captured in this video:
Step 1 - The catalyst market - Wind powered water injection (WIN WIN)
To realise the vision outlined above, we knew we had to partner with the oil and gas industry at significant scale. This was in 2015, when the oil majors were not as vocal as they are today about diversifying their energy portfolios into renewables. However, our initial research showed that water injection was an obvious candidate for wind power – and we invited the industry to work with us in a Joint Industry Project (JIP). In just a few months, eight companies signed up, including Exxon Mobil, ENI Norge, Nexen Petroleum, Equinor, who were implementing their very successful Hywind commercial floating wind farm off Peterhead in Scotland, and several others. Encouragingly, we also attracted Japanese component suppliers into the JIP.
In this first phase, we were working directly with the owners of oil reservoirs to see if there were any showstoppers. Our conclusion was that it is certainly not possible to apply the concept to all reservoirs, but we found – to the excitement of all – that there is significant potential for many assets and fields around the world. Certain specific conditions are key, and each field needs to be investigated individually to assess the potential. The key characteristics are as follows:
- Wind resources – clearly have to be adequate, and as a rule of thumb, the further from equator the more wind. As with all thumb-based rules, there are exceptions; in this case, the outstanding exceptions are the coast of northern Brazil, and the Gulf of Mexico.
- Depth –There are many bathymetries that work well for floating wind turbines, which can be moored down to 1000 m. For example, the Norwegian Continental Shelf, where many fields are at 200m – 400m, and there are similar conditions off Newfoundland, northern Brazil, etc.
- Cost – there are many parameters to consider, including the age and design of platforms – which may make the cost of retrofitting power plants for enhanced oil recovery (EOR) prohibitive, or require a costly shut-down. Weighed against those costs, WIN WIN has the advantage of being built and installed separately and can be moved to new injections wells if necessary, thus saving significant capital costs.
- Distance – from injector well to production platform is critical. The further away from the platform, the greater the potential for the field itself to act as a ‘battery’ for wind-powered water injection. Variable power, and hence variable rates of injection, builds up pressure over time, and fluctuations are of less concern. Distance also impacts the cost of flow lines from the platform to the injector site, which is also where direct, in situ, wind powered injection makes a lot of sense.
Lab testing the WIN WIN concept
With the positive conclusions from Phase 1, we had a fair wind propelling us into the second, more technical, phase. This time, we were joined by Exxon Mobil and Vår Energy (ENI) as core partners, supplemented by support from the Norwegian Research Council (NRC).
With the aim of producing a commercial case for WIN WIN, the partners sat down to figure out what is truly new and untested about the WIN WIN concept. Turbine technology is proven; floating wind is no longer novel (as demonstrated by Equinor’s Hywind). Also, pumping technology is established. And so, what is new is the integration of these technologies and the design of an autonomous microgrid for wind-powered EOR.
The biggest challenge we faced is that large turbines are designed to be connected to stable power grids. In this case, we need a microgrid that copes with variable power from a single turbine, with continuous power requirements for functions like lighting, communications and control & instrumentation. Our major insight was that continuous power is not needed for uninterrupted pumping – the reservoir itself can function as a ‘battery’ for the system, as long as reservoir pressure can be built up and maintained over time. But a smaller, conventional battery is required for ancillary power requirements when the wind isn’t blowing.
With the aid of a NOK 10 million grant from the NRC, we bought hardware and built a simulated microgrid for testing at DNV GL’s power laboratory in Arnhem, in the Netherlands. There, we were able to design and test an optimal control system for stability of the microgrid, able to handle unforeseen events, like a pump failure or turbine malfunctions.
We have shown that the WIN WIN concept is not only technical feasible, but it pays
Accepting that each system needs to be customised for specific fields, we designed a prototype system around a fairly typical ‘virtual’ injection site at a water depth of 200 m, 30 km distance from platform to injector, and with target injection of 44 000 barrels of water per day at average wind speeds of 9.6 m/s. In other words, a very familiar North Sea scenario, with a 6 MW turbine – the workhorse of offshore wind industry today.
We were also able to show that the design has flexibility – the system can be tuned for different scenarios. For example, a bigger turbine and pump can be installed for heavier injection work, and vice versa for smaller fields.
The net result of Phase 2 is that we now have concept that is fully tested against reservoir requirements, and a lab-tested microgrid. The JIP partners are justifiably proud of the achievement, and the stage is now set for…
In my view, potentially substantial rewards await a first mover willing to build a prototype to increase technology readiness and optimize system integration.
Remi Eriksen - Group President & CEO, DNV GL
The concept was launched at OTC 2019 and we are holding follow-on technical seminars and meetings with owners, operators and OEM suppliers with the aim of finding a partner – or consortium – to take this concept into physical reality. In other words, someone to build a prototype to mature the technology further. In fact, given the appetite for corporate venture capital these days, this could be an ideal project for investors / venture capitalists.
As DNV GL Group President & CEO stated at OTC, there is no doubt in our minds that a first mover on this could gain real advantage. Firstly, we have shown that the WIN WIN concept is not only technical feasible, but it pays. Simply put, under the right conditions – and there are many possible scenarios – wind powered water injection can save millions of dollars.
To aid the construction of a prototype, a first mover also has free access to our test data as a well as a comprehensive Guideline document produced by DNV GL covering critical aspects of the application, including regulatory considerations.
A new mindset
Clearly, I have ‘lived’ with this concept since its inception – and I am well aware that there can be some sceptical reactions to this novel concept that need to be overcome.
There is a tendency – still – by many to associate renewables with subsidies and compromise. But offshore wind is now a proven, cost effective technology, and expanding at an incredible rate. There is also often an assumption that you need continuous power for water injection; in fact, under the right conditions, the reservoir itself provides the energy storage required. Finally, there may be a tendency for an engineer to think that it’ll never work on ‘my’ field, with its unique characteristics – and I can’t emphasise enough that there is considerable flexibility in the WIN WIN concept, and like any system it will be designed to meet the requirements for each specific application.
On the other hand, I do feel a new mindset is taking hold in oil and gas. There is the realisation that radical transformation is happening in the industry – both for survival and to ensure that the industry itself adapts to the energy transition that is playing out. I believe that WIN WIN could be the beginning of a successful and deep integration of oil and gas with renewables. Beyond water injection, there could be several other processes that are amenable to wind power, with the addition of ever-cheaper energy storage at small and large scale.
A broad, but personal, view
It is inspiration that unlocks the future - technology will catch up!
A continued development of the integration of offshore wind and oil and gas brings us back to the grand vision we developed for offshore wind, a part of DNV GL’s 150th anniversary celebrations. Oil and gas operators can play a big role in the pervasive uptake of floating wind from 2025 onwards – the industry has the scale and competence to do so, but even more importantly, there are clear commercial advantages.
But let me make this a bit more personal – because, after all, even the biggest companies are made up of individuals. I think there are many engineers out there who, like me, feel that, right now, we need to challenge ourselves – we are motivated by working for a higher purpose, and that we get a kick out of bringing together smart and experienced individuals to solve problems that edge the world a step closer to sustainability. We need to be brave, bold, innovative and creative. We need to challenge written and unwritten rules in our industries, we need to ask ourselves, colleagues, managers and customers some uncomfortable questions, and we need to support others who dare to explore new ideas. We need to become a part of the solution and few industries, if any, have as much to contribute with to the climate crisis as the oil and gas industry.
And remember: It is inspiration that unlocks the future - technology will catch up!