Is the future of the blue sea red, brown or green?
Energy Blog, 3 June 2020
In these extraordinary times, we have been thinking a lot about biomimicry, which, as you probably know, is an approach of taking innovations, patterns and solutions that already exist in nature and applying them to technology.
The core idea is that Mother Nature who has spent billions of years being creative by necessity, has already solved many of the problems humanity is facing so we can helpfully learn from her successes and avoid her mistakes.
A good example of this is the humble seaweed which is the collective noun for a range of species of multicellular algae. All seaweeds share a common ancestor with trees and mosses and belong to one of three groups commonly known as reds, browns and greens.
For such a small and unassuming plant, seaweed could play a big part in the battle against climate change.
The answer is diverse yet simple. Seaweed aquaculture, the fastest-growing component of global food production, offers various solutions to mitigate climate change.
We already know that our “underwater forests” of seaweed are one of the planet’s largest CO2 sinks, absorbing at least 25 percent of the atmospheric CO2 we emit each year thereby reducing the effect of global warming. Seaweed also contributes to climate change adaptation by protecting shorelines, reducing ocean acidification and damping wave energy.
But the magic doesn’t stop there. As you might know, emissions from livestock produce a major source of methane, which warms our planet up to 86 times as much as CO2. In recent years, researchers found that by adding seaweed to animal feed, they could cut methane production by nearly 60%. One particular type of red algae called Asparagopsis seems particularly suited for this and subject to regulatory approval it could be appearing in cow’s diet in the near future.
It is likely that seaweeds, being rich in minerals, will become a vital ingredient for the global animal food industry. This development coupled with global population growth has doubled worldwide production in the last 10 years and it now stands at 2.2 million tones. Global industry has an estimated market value of USD 10 billion (2016), with China, Indonesia and the Philippines representing almost 95% of global production, while Europe represents about 1% delivering mostly wild harvest production.
As well as animal feed production, seaweed can also play a significant role in crop fertilization. With the expected future freshwater shortages in parts of Europe as well as the ecological debate about the negative impact of excess fertilizers on soil, we are likely to see a significant reduction in the amount of water and fertilizer used in agriculture.
Crop-based bio stimulants based on seaweed have shown to have a positive impact on the amount of water and fertile used by crops resulting in a strong demand for these products from the horticulture sector.
What does this mean for offshore wind?
As we are already seeing with offshore wind, developers are looking to the oceans as a place to develop decarbonized energy systems which reduce CO2 emissions and air pollution. However, there’s only so much suitable ocean space available near to shore. We will need to optimize the use of our oceans as potential sites will become scarcer in the longer term. This scarcity is leading to a growing emphasis on multi-use solutions which combine offshore wind with a synergistic technology such as hydrogen production or seaweed cultivation.
All of these developments mean that the global demand for seaweed is likely to continue and it is possible that seaweed farms could be installed in parts of offshore wind developments provided the business case is economically viable. However, like many seemingly simple ideas, it is not that straightforward. Building and running offshore winds farms is already a tricky, technically challenging business and the offshore wind developer and seaweed farmer will have to assess the impact on construction and operations by combining this with a seaweed farm as well.
It is likely that the construction of the seaweed farm will have to be performed by the offshore wind developer, given that the existing seaweed farmers do not have the expertise or capabilities. Returns on offshore wind farms are already falling and careful consideration will need to be given as to whether the additional job creation and positive impact on CO2 reduction could translate into a monetary advantage for the offshore wind developer taking on the additional costs and risks of adding a seaweed farm.
Seaweed farmers and offshore wind developers will also have to carefully decide on operations and management of safety issues. Furthermore, transparent agreements on who will be responsible for lost income due to downtime or damages are necessary to avoid future disputes.
However, despite these challenges, governments are debating the challenge to find sustainable solutions in the North Sea in conjunction with food production (fisheries and aquaculture) and the restoration of biodiversity. The European Commission already promotes the development of seaweed practices due to its various environmental benefits and economic potential.
Consequently, we may see that future offshore wind energy tenders in certain countries (e.g. Netherlands and Belgium) might require tenderers to include a solution for food or nature restoration as part of the bidding criteria.
What are we currently doing?
We have been carefully tracking these developments and in collaboration with a nonprofit making seaweed think tank, Stichting Noordzee Boerderij, we are developing a business case for seaweed farmers, outlining the many possibilities and necessary actions for each member of the value chain. The results of our work will also lay out the next steps required in order to combine the seaweed farm with an offshore wind farm.
In conclusion, small red, brown or green seaweed may have a big part to play in a green future for the planet. By mimicking Mother Nature we can use these little plants to absorb CO2, reduce methane emissions from livestock and develop crops that require less water and fertilizer. Given the scarcity of suitable farming sites near the shore, combining seaweed cultivation with offshore wind developments seems like a sensible idea. However, there are considerable challenges along the way and in a world of falling returns, experienced wind farm developers remain wary of incurring additional expenditure unnecessarily. Governments may have a role to play here in stimulating seaweed production as part of the bidding criteria for future offshore leases. In the future, seaweed cultivation coupled with offshore wind may mean that the North Sea may be red, brown or green as well as blue.