Thistle: a new energy source?

Southern Italy and, more generally, the entire Mediterranean area, may have discovered a new source of biofuels: thistle. This plant not only grows spontaneously, but has been traditionally cultivated as a vegetable since Roman times. It thrives in environments with irregular water levels and requires little artificial irrigation. Its growth cycle is from autumn to spring, which enables it to make maximum use of water derived from natural precipitation. The roots of the thistle are particularly rich in sugars and therefore have considerable potential for use in the production of energy from biomass. The roots of the thistle are particularly rich in sugars and therefore offer notable prospects for use in the production of energy from biomass. It is also possible to produce biodiesel using oil extracted from the seeds of this “home-grown” plant.

Currently a 20-hectare area is being used to grow thistle in Calabria, as part of an experimental project by ISAFoM (Institute for Mediterranean agricultural and forestry systems). The yield is about 15 tonnes per hectare, from which it is possible to obtain, by combustion, between 16,500 and 17,000 kilojoules of energy per kilogramme (kJ/kg).The fact that thistle easily adapts to soil with low moisture content, helps to eliminate competition for arable land that can be used for food crops. It is an energy resource which, if the ongoing studies and trials report positive results, could prove to be important for the sustainable development of Italy and all countries in the Mediterranean basin.

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