Currently we are working on a project for a boat design, which features a zero emission sustainable source of electricity for the on-board systems. Wonderful endeavour, great project to contribute to.
The highest aspiration, of course, is to become fully sustainable. To accomplish that, we have to look at the total ecological impact: construction, operation and dismantling. The ‘ecological footprint’ is a measuring tool that can help us with this. But what is it? How is it measured?
The ecological footprint of an object (person or thing) is the total area of biologically productive land and water needed to produce all the resources and energy flows used by this object (food, energy, material), and to break down or compensate for all the waste produced by that object. The unit in which we measure a footprint is hectares. See the figure below showing the footprint of a human being and his consumption in order of magnitude:
For reference, the Earth’s biological productive surface offers 1.6 hectares per inhabitant (2018 figures). However, the footprint of the average human is now 2.8 hectares. Since 1970, we have consumed more globally than Mother Earth can regenerate. Not a sustainable situation. Work to do!
The ecological footprint of a boat consists of 1) the production (materials, parts, energy used during construction), 2) the use (maintenance, energy use) and 3) the demolition after decommissioning, and the disposing or recycling of all materials and parts.
The starting point is to calculate the total production footprint of a boat in the design phase. Nowadays, with the help of available databases, we can track all kinds of facts and figures for each component such as weight, energy consumption for energy balance, cost, and required maintenance. In the same database, we can also record the footprint of the components and materials used. Combine this with the footprint for assembling all these components and materials and there it is: the actual production footprint of a turnkey boat.
Second step is to calculate the footprint of the ship in operation. If electrical energy is used for the propulsion and other ship operations, there will be no direct emission. But still the generation and transport of electricity counts. Using wind and solar power, again there are no direct emissions. Nevertheless, the relative footprint of the wind turbine or solar panels needs to be added. Is electricity coming from a coal fired power plant? In that situation, an electric boat actually runs on coal. Same story for your Tesla or any electrical/hybrid car! When calculating the footprint, we also need to include the relatively footprint for the coal plant and the mining, transport and burning of the coals. Including the direct emissions from the coal plant.
Lastly, we need to analyse the dismantling of the boat to determine the end-of-life footprint. Recycling can be implemented to reduce the ecological impact. Determining options for recycling in the design stage can bring a positive impact to the overall footprint of the boat.
But anyway, work to be done: for each boat to be produced, let us start to establish the actual footprint of production, use and demolition in the design stage.
Comments on this topic are appreciated! How do you see the footprint of ships? How can we all – designer, yard, supplier, owner and scrapper – contribute to reducing the ecological impact of shipping?
Currently, there is a lot of focus on reducing the footprint of the propulsion system. But how big of a contribution does propulsion make to the total footprint? If you have data, please share!