Reimagining an offshore wind farm #1
In my previous blog, we talked about reimagining ocean developments; I’m based in the UK and one of the biggest areas of ocean development here is set to be in offshore wind, in the form of fixed and floating wind turbines. As we seek to decarbonise our energy provision to use renewable energy, the UK government’s policies have significantly supported siting large wind farms offshore.
In the UK, the target for the capacity of electrical power from offshore wind has been set at 40GW by 2030. The UK government’s Committee on Climate Change has suggested the UK should have installed 100GW of offshore wind by 2050 to help reach net zero GHG emissions.
Let’s put this into a possible physical context: Assuming each turbine is rated at an average generating power of 10MW, then 100GW capacity would require 10,000 turbines to be installed. I’m sure larger turbines are planned, yet 10MW models are commercially available today. Let’s take as a close enough example, the MHI Vestas V174–9.5 which is rated at 9.5MW and has a rotor diameter of 174m. A quite common assumption when working out how far apart to space turbines is 10 times their diameter. This is to allow the wakes, or mixed air behind the turbines to be restored to something similar to the speed and turbulence of the surrounding wind. Using that gap of 10 times the diameter, spacings of more than 1.74km would be needed.
If the turbines were spaced at 1.74km apart, this 100GW of turbines, roughly, could cover an area of 174km by 174km or 30,276km². Although they would not all be sited in one area. For comparison, the area of Dogger Bank is 17,600km² and the land area of the U.K. is 241,930km². Dogger Bank is offered here for comparison as significant farms are planned for Dogger Bank, Eastern Regions, the South East and Northern Wales and the Irish Sea.
Why does this matter?
The amount of ocean area likely to be contained within the farms is about a 12.5% of the UK land area. This is quite substantial when you think about the cultural, economic and physical diversity of the UK. This isn’t vacant space. It is being used by other species and earth’s processes, which keep us alive.
The need for electricity influences the number of turbines we will need. The UK’s peak electricity demand at present is around 45GW. Looking at the UK energy flows, we can see that we have some significant changes to make as we further seek to decarbonise our energy supply, shown by the purple coloured fossil fuel based natural gas stream and the green petroleum streams below. Working with the present demand level, if we shift a large amount of the petroleum used in transport, and natural gas supplied for domestic heating and cooking (around 81 MTOE) to electricity, we will need about 942,030GWh of renewable electricity. If we did this solely via wind turbines, this might mean around 27,000 of the 10MW turbines to be installed, with a combined rated capacity of 270GW. This is just under 3x the 100GW suggestion, and just under 7x the 40GW target at the moment.
This is an example; multiple technological, economic and social solutions will be needed to achieve this decarbonisation, and many scenarios and pathways have been suggested such as by the CCC, the Zero Carbon Britain project, Friends of the Earth.
Our demands on the ocean matter. Our ocean developments meet mostly land-based human need and so land based intention and activity matters: The amount of electricity generating capacity needed is shaped by government policy, but more local actions will also innovate and evolve the scenarios. As more regions and cities work with their own approaches, such as city portraits, whether we have more offshore wind, more land-use change or more carbon capture and storage will evolve. Looking across the water, Amsterdam, for example, has a city target to ‘Utilise two thirds of all solar energy potential (1000MW) from within its area by 2040 — enough to power 450,000 households’.
If the we increase distributed generation on land, close to the place of demand reducing transmission losses, and with a feedback of information on how much is produced developed in the minds of the users, perhaps the number of turbines proposed will not extend beyond the 100GW proposed.
What does this mean for the oceans?
Perhaps, not many of you envisaged km after km of turbines spanning the North Sea, and is this what you want to see? Do you have a vision for the oceans of the future?
I’m imagining an ocean, under the stress we created, but which is abated and supported by our intentions and actions in it as well as those ashore.
What if, with these 10,000 turbines we are planning, we improved the condition of our oceans and our coastlines?
What if out-of-sight was not out-of-mind, and the realities of where we source our energy from was not disconnected from our understanding of it?
Systems which are regenerative restore their own sources of energy and materials, they are designed considering the whole system to be resilient and equitable, they integrate the needs of society with the integrity of nature.
Many of the wind farms developed are not regenerative by design, so here we’re going to experiment to see whether a wind farm development itself can help us move towards an economy fit for the 21st century.
Plunging right in
In the last blog, I introduced an exploration applying Doughnut Economics Action Lab’s approach for an ocean development. Here we explore creating a snapshot for an offshore wind farm.
The targets for a particular type of ocean development, and indeed a specific unique installation requires collaboration with a range of stakeholders, including the wider community. Their view is subjective and this subjective nature is important to capture, as they are decision makers or influencers of the development process. Creating a city snapshot is not just intended as abstract analysis but to generate conversation and understanding from which innovation and changing behaviours follow. So your thoughts and suggestions are valuable, do get in touch!
Let’s dive in: To enable the downscaling of the doughnut, DEAL uses different lenses working with Amsterdam’s residents to examine and craft the Action Plan for Amsterdam. I’ve tweaked this for a wind farm:
Over the next few blogs, we’ll look through each lens, but will start here with:
Local Social
Through the local social lens, the aspirations of the people living in and served by a city are compared with a city’s performance at meeting it. These aspirations are grouped around the themes of:
HEALTHY: Health, Housing, Water, Food
EMPOWERED: Peace & Justice, Social Equity, Political Voice, Equality in Diversity
CONNECTED: Connectivity, Community, Mobility, Culture
ENABLED: Jobs, Income, Education, Energy
This prompts the questions:
What would it mean for an offshore wind farm development to deliver people's needs locally, what would it mean for people involved or living locally to thrive?
I’ve started to suggest some targets, sourcing inspiration from my experience and the aspirations of the residents of Amsterdam. Some of these targets may already be met, others are not and, for many, we don’t know. While reading them I ask you to consider:
What specific goals would we need to bring them to a position where they can be evaluated?
Is this the right language representing the many disciplines in this multidisciplinary approach?
Get in touch with your thoughts and comments here, or via our group on linkedin.
I’m working with the University of Southampton’s Royal Academy of Engineering Chair in Emerging Technologies for Intelligent & Resilient Ocean Engineering. We’re exploring how we can reimagine our relationship with ocean development and how we can change our approach to the oceans to shape mutual and cooperative relationships through our ocean actions.
