Energy from the sea: challenges for social, economic, scientific and technological collaboration

by Giuseppe Manzella, OceanHis SrL


This note was stimulated by the article published in OMEGANEWS on July 30, 2022: Mediterranean today and tomorrow. The author, Lavinio Gualdesi, presented a series of problems related to the history of the Mediterranean, a space – movement area (as called by Fernand Braudel) which saw the meeting and clash of different civilizations and, at the same time, a wonderful exchange of cultures. The Mediterranean region was (and still is) a theatre with two voices, one from the West and the other from the East. Gualdesi clearly describes the Mediterranean as a small universe in which the problems of anthropization and pollution take on enormous dimensions: climate change is more evident than in other areas of the global ocean, effects of pollutants of terrestrial origin extremely harmful, especially when associated to extreme events. The challenge is to combine human needs with sustainable development so as humanity can improve the quality of life and protect the environment. The goal can be achieved with a holistic approach combined with continuous monitoring of ‘essential’ environmental parameters in order to verify that development actions do not create adverse conditions for man and the environment in which he lives. This short note is based on the concepts expressed in a book (Ocean Science Data: Collection, Management, Networking and Services) and in particular in chapter 7: How can ocean science observations contribute to humanity? The book postulates a knowledge society in which scientific and civil communities work together (co-production) with the aim of triggering a process of interdisciplinary cross-fertilization, improvement of critical thinking and knowledge-based management skills.

Co-production and interdisciplinarity.

An example of these concepts is very well provided by wind farms at sea. The European Commission funded a study that was defined as a ‘stress test’ for the evaluation of knowledge acquired in the marine environment for the purpose of useful applications to European society. One of these tests was dedicated to ‘wind farm siting’. The authors of the analysis defined the list of data necessary for the evaluation of a wind farm installation:

  1. Atmospheric parameters (wind, pressure, density, humidity, temperature);
  2. Marine parameters (level, temperature, salinity, currents, wave frequency and direction, wave height, maximum expected height;
  3. Biological information (birds, marine mammals, reptiles, fish – species, protection status, migratory trajectories, abundance, breeding areas);
  4. Seabed (bathymetry, bottom and substrate characteristics, sedimentary evolution, coastline evolution, seabed energy, angiosperms, macro algae, seabed fauna, seismic structure and seismic events);
  5. Human activities (fishing, maritime traffic, radar infrastructure, port traffic, coastal use, nautical activities, locations with coast guards, submarine cables, logistical accesses, ports, local, regional, national, European regulations).

In total, the authors found the characteristics of 30 parameters / information at various levels of detail and 30 data sources for environmental data alone. A first conclusion of the ‘stress test’ analysis was the need to have a working group composed byhistorians, mathematicians, physicists, biologists, geologists, chemists and environmental managers in general. A second conclusion does not derive from the experience of the stress test, but from a more general considerations on physics and biology. The wind, with its power of mixing water, is a factor that allows atmospheric oxygen to be transported within sea waters (for simplicity we do not consider other factors such as the dispersion of pollutants and the influence on currents). Subtracting energy ‘upstream’ with a wind power plant of a certain size, means having a decrease in energy ‘downstream’, thus reducing the ability to mix water in coastal areas with consequences also on biology and therefore on activities related to fishery. The example of the wind farm shows how it is not enough to think only in engineering terms, but it is necessary to have an interdisciplinary working group to which continuous monitoring must be added during and after the construction of a plant, to correct errors in the design phase or to evaluate environmental effects not considered in advance.

In other fields, an excellent example of the application of this working method was offered in the construction of the ØresundBridge (between Denmark and Sweden).

We can conclude this paragraph by quoting Friedrich Heinrich Alexander Freiherr von Humboldt (Berlin, September 14, 1769 – Berlin, May 6, 1859), naturalist, explorer, geographer and botanist whose ambition was to understand the phenomena of physical objects in their general connection and to represent nature as a single large whole moved and animated by internal forces (Kosmos, 1845 – 1862).

Energy from the motions of the sea

This note continues with the same title as the last paragraph of the Mediterranean today and tomorrow. It can easily be assumed that the data required for the definition of sites where to install an energy production system are the same as for the wind field with other additions such as oxygen, chlorophyll, transparency, phytoplankton, zooplankton. The initial data for a feasibility study that of the currents, whatever could be their nature: residual, induced by the wind, tides or earth’s rotation. In the Mediterranean the tidal currents are generally not very energetic with the exception of a few areas such as the North Adriatic, the Gulf of Sirte, the Strait of Messina. Energy and sufficiently stable currents were measured on the narrow continental shelf of the Ligurian Sea.

In addition to the problem of intensity, the exploitation of the tides collides in many cases with the factors listed in points 4 and 5 above. Other types of currents could be explored, such as those existing in the straits (such as the Corsica channel) or the so-called ‘coastal boundary currents’, such as those of the Ligurian Sea, where currents ‘trapped’ by bathymetry have also been found, i.e. currents close to the outer edge of the continental shelf (the ‘shelf break’) that are sufficiently energetic, even if their intensity depends on the wind regimes (strong currents in winter – up to about two knots – and weak in summer). In the case of exploitation of ‘coastal currents’ it is advisable to verify that they aren’t associated with upwelling phenomena. These phenomena are very important from a biological point of view, since they bring nutrients to the euphotic zone, where sunlight can trigger productivity phenomena. The conclusion regarding the exploitation of currents remains the same as for wind farms: interdisciplinary studies and constant monitoring of environmental conditions are needed.


I like to finish this note by taking up the content of chapter 7 of Ocean Science Data mentioned in the introduction. Here the problem of training young scholars arose, who must acquire technical-scientific and cultural skills in general in order to be able to answer four fundamental questions for a changing environment:

1) What are the possible short- and long-term changes?

2) What are the risks and implications of these changes for human development and for the diversity of life on Earth?

3) How can a society adapt to the physical, social and ecological consequences of changes and what are the barriers that limit adaptation actions and potential opportunities?

4) How can the integrity, diversity and functioning of an evolving ecological system be sustained in order to sustain life in the oceans and its ecosystems while equally supporting human needs and health?

The formative process is less difficult than one might suppose. Renowned ‘teachers’ have engaged in it, among which I like to quote Immanuel Kant: The sea is the mother not only of all waters, of all sources and of all rivers, to which it provides existence with its evaporation, but also of everything that exists; still today it produces and feeds more animal species than the earth (Physical Geography, 1750 – 1790).

Giuseppe Manzella, OceanHis SrL