Aim of the case study
The aim of this pilot study is to define a procedure for integrated and multi-level accounting of the nexus (water, energy, food and land use) in relation at the use of freshwater from desalination powered by windmills to irrigate crops in a farm in Gran Canaria.
This case illustrates how to implement a Water-Energy-Food (WEF) NEXUS assessment using the MuSIASEM 2.0 approach: It shows the usefulness of the tool with some clear evidences as example of the type of outputs obtained. It explains in details the various steps required for quantifying the production of energy, water and food and the associated requirements and resources. It explains how to make a system representation in order to arrange the elements required to represent the various relations of exchange within the WEF system and between the WEF system and outer systems (purchased water, electricity or crops sold to the market). This figure (next page) makes it possible to distinguish between functional and structural elements useful to scale up the information, or to make extrapolations of the analysis to other territories.
The innovative analysis based on the concept of “processor” – a data array describing the profile of expected inputs and outputs, that can be scaled across functional and structural elements - makes it possible to integrate:
- technical analysis (technical coefficients);
- economic analysis (costs and revenues in monetary terms);
- biophysical analysis of the external constraints (requirement of inputs on the supply side and sink capacity).
Policy relevant insights
Even though the contribution of alternative energy to generate an alternative fresh water source improves the productivity of the agricultural system (an important aspect in the Canary Archipelagous) the results of the analysis carried out in this pilot case flags two relevant aspects to consider, when assessing this technology:
- desalination using wind energy is economically viable in this case only because of the existence of high agricultural subsidies making it possible to cover the high costs of this type of freshwater source. So the viability of this system elsewhere depends on the level of water scarcity and the possibility of providing subsidies to agricultural production.
- the considered WEF system is not fully self-sufficient, it still relies on water and electricity from external suppliers.
In the rest of the project we will develop more complex analysis and carry out participatory processes to test the usefulness of this approach in real situations.