Wind farm off Norfolk beach

Six vital questions for the UK offshore wind sector

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From the technical challenges of connecting with the onshore grid to the consequences of Brexit, the UK will have to negotiate a number of obstacles if it is to achieve its hopes for developing offshore wind’s contribution to the national electricity supply.

Generating more electricity from offshore wind than anywhere else in the world, the UK is at the forefront of exploiting the fastest-growing source of energy. However, with an ever-more congested onshore grid, supply chains under pressure and an increasingly competitive global scene, there are several major issues that industry needs to consider as it enters the next phase of developing infrastructure.

As demand increases, what will offshore-to-onshore connection look like?

More than 20 years after the first offshore wind farm was installed in the UK, many of the connection points to the onshore grid are becoming saturated, so there is a question as to what shape the offshore part of the network will take. National Grid ESO has identified within the Holistic Network Design for 2030 onwards how a more coordinated approach between onshore and offshore network design will benefit consumers and stakeholders.

This is just one option put forward in a competitive pan-European marketplace. The industry needs to consider whether a densely interconnected meshed DC grid, often suggested as the universal panacea for congestion at connection points, but still largely untested, is optimal for an island nation like the UK.

A meshed ‘supergrid’ network in the North Sea using offshore wind farms as nodes has been in discussion for around 15 years and while, on paper, DC mesh has seemed like a great idea, for many technical and commercial reasons it has not yet taken off.

Is the period between now and 2030 the time where a meshed concept gains momentum throughout Europe, or is the commitment required just so large that we will continue to build the network one long radial piece at a time? Should an element of central planning return to the EU electricity network?

How can we improve offshore to onshore grid integration?

Whereas the US started with a blank sheet of paper, there are already 25 years of water under the bridge for the European network with regards to international links and integrating offshore wind power. This has created a complicated, multilayered network that can’t be entirely ‘untangled’ without significant changes to the network configuration and the ensuing public and political stakeholder concern. No single technology offers a ‘magic bullet’ solution, so which of our technical tools - such as DC transmission networks, energy storage, and load control with deferment - do we deploy and where?

With so many assets halfway through their working life and other assets getting towards the end of their design life, we need to explore whether system elements can be repurposed, or if they must be simply replaced. It seems unlikely that future networks will be based on a revolutionary technology, so are we faced with sporadic evolution? Can we focus such an evolutionary approach and pick the winners early?

How will offshore transmission projects be financed?

There have been a few shifts between public and private finance for the offshore wind sector in the UK. The industry went through a period of initial government supported funding, followed by a period of private consortium funding. Now we are back to reduced public support for offshore renewables through price control and support mechanisms.

On the one hand, the costs of offshore wind are being driven down the technology learning curve, as the increasing size of turbines and ambitious dimensions of projects have led to reduced installation costs and economies of scale. The expectation is that the rest of the supply chain costs will continue to come down as expertise grows, albeit at a slower rate, and the latest techniques, vessels and equipment are incorporated.

However, it has been noted that one of the challenges in executing the Department for Business Energy & Industrial Strategy’s new British Energy Security Strategy (BESS) is the scale of investment required to continue to reduce or even stabilise prices, with the low-hanging fruit of technology development already taken. BEIS recognises the need for private investment and the requirement for the current contracts for difference process to be changed in order to deal with the significant change in the volume of renewables being generated.

Whilst oil and gas players have acknowledged that carbon is on its way out by 2050, the political and social agenda is pushing the renewables market to become cost competitive, bringing in large economies of scale and requiring deep pockets to drive development. The picture is therefore by no means clear, particularly as governments might waiver on commitments to reduce carbon emissions given recent global events.

Can we expect some investment certainty for particular energy strategies to a 20 or 30-year timescale so we can make a relentless push to decarbonise?

Is it time to develop deeper penetration of floating wind in deeper water?

As the shallower parts of the continental shelf become saturated with fixed-bottom turbines, the industry must consider whether it is time to develop much greater penetration of floating wind generation in deeper water. If this transition is made, it will be important to learn lessons from the US on how to make this a success, as the US wind in deep water sector is about to receive a large amount of investment, particularly as a result of Californian pull-through of desire to control and stabilise the cost of energy. This will likely result in the US descending the technology learning curve at a faster pace than the EU. Is this a repeating pattern, where the UK and EU performs the hard miles of Research & Development but then under-funds deployment to capitalise on savings through ambition and scale?

The UK and Europe should pay attention to what is happening across the Atlantic to learn from the inevitable mistakes that will be made and the solutions which result. The upcoming ScotWind programme, which will lease areas of the sea bed around Scotland and looks to create up to 25GW of new generating capacity, will be built over the next decade and is likely to be the largest floating wind project in Europe. For the UK to stay ahead of the curve, the industry needs to start thinking about how hard to push scale-up where the UK has weaker pull-through, so that the UK matures geographically relevant technologies.

What effect does the global resource shortage have on UK development?

A corollary question for the industry globally is whether there will be enough resources to meet the global demand for floating wind energy generation. Countries such as Japan and China have massive demand for new energy sources and vast amounts of deep water just off their coasts. The moment the technology becomes available, they will want to replicate it. This could cause a global resource problem, both in terms of the parts and raw materials but also people and technical expertise, which in turn could affect the UK’s ability to develop and progress. Other territories such as the US, where the energy price is higher per delivered megawatt per hour, can afford to invest more in offshore wind projects, whereas the cost/price balance in the UK is lower.

In addition, there is the issue of brain drain and personnel resources. At the moment, the leading players in this area are from the UK and Europe, but they are being pulled to regional offices in the US and the Far East. The industry therefore needs to consider how it can work to control the aspirations elsewhere, impacting the aspirations here in the UK.

All parts of the UK and EU supply chain will come under even greater stress. Which nations will break first and who will stay the course?

With the UK having left the European Union, what does our trading relationship look like for energy?

Exactly how the UK leaving the European Union will affect the offshore wind sector remains to be seen. Domestic policies, trade deals and our relationships with our European partners will affect everything from regulation to raw materials. The full impact from current international volatility, which has been particularly impactful on energy supply, also remains to be seen. This final question is not for technologists or engineers but rather for economists and politicians; however, it will be key to the future of the industry.

Tony Appleton is offshore wind director and David Slee is submarine cable manager at Burns & McDonnell.

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