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This article aims to present an evaluation of the environmental performance of a combustion polygeneration plant fed with lignocellulosic material from cardoon (Cynara cardunculus L.) through the technique of Life Cycle Assessment (LCA). The system boundaries encompassed macro-phases of crop production, transportation, and polygeneration processes that were able to produce 100 kW of electricity, a residual thermal energy recovery system and district heating and cooling with 270 kW of heating, and a 140 kW of cooling. The LCA was performed using Cumulative Energy Demand and ReCiPe Life Cycle Impact Assessment methods through midpoint and endpoint indicators. From 2000 h/year, 165.92 GJ of electricity and 667.23 GJ of primary energy were consumed, and 32.82 tCO2eq were emitted. The rates of Greenhouse Gas (GHG) and energy demand per MJ produced were 0.08 MJSE/MJPD, 0.30 MJPE/MJPD, and 0.01 kgCO2eq/MJPD. According to the ReCiPe method, the impact categories with the highest impact loads were Terrestrial ecotoxicity (2.44%), Freshwater ecotoxicity (32.21%), Marine ecotoxicity (50.10%), Human carcinogenic toxicity (8.75%), and Human non-carcinogenic toxicity (4.76%). Comparing the same energy outputs produced by Italian power and gas grids, the proposed polygeneration plant was able to reduce primary energy demand and GHG emissions by 80 and 81%, respectively, in addition to reducing the emissions of the five main categories of impacts by between 25 and 73%.

The focus of this study is to analyze the energy flows related to cardoon oil processing based on the estimated electricity consumption. It was carried out in a prototype oilseed extraction plant located in Umbria Region, Italy. This installation consists of the following processes: seed weight-storage, transportation, sifting, milling, filtering, and oil storage. Approximately 49,000 kg dry basis (DB) of cardoon seeds (Cynara cardunculus) were processed. Cardoon seeds were chosen as a feedstock due to their sustainability characteristics. Before processing, samples of raw material were analyzed in terms of moisture, oil content, impurity, density, and lower heating value. The input–output flows were measured in terms of weight and energy consumption. Its data were used to perform the mass-energy balance and estimate the efficiency of processes. About 8505 kg of filtered oil was obtained from raw material. The efficiency of the process chain was 84.42% concerning the oil content in the seeds. For the same period, the plant required a total of 17,556 MJ of electric energy from the grid for its operation. 321,507 MJ were obtained from oil and 688,875 MJ from oilcake. About 5.48% of the energy produced by oil extraction was virtually used in the process.

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Given the current scenario of increasing environmental problems associated with the need for rapid energy transition, this article aimed to investigate the implementation of Cynara cardunculus L. (cardoon), a plant with high environmental performance, as a source of energy resources. This study presented thLife Cycle Assessment of two energy production chains—for the polygeneration of power, heat, and cooling; and to produce biodiesel—fed with cardoon seeds, in addition to comparing these chains with the use of the traditional Italian grids (power and gas) and with the production of diesel based on palm, soybean, and rapeseed. Approximately 49 t of seeds were cultivated and processed, yielding 8.5 t of oil. The system boundaries encompass three main macro-phases, cardoon production, oil extraction, and, depending on the application, energy generation (polygeneration) or transesterification (biodiesel). The models were developed using the software SimaPro V9.3.0.2, and the inventory was based on the database ecoinvent V3.8. The Life Cycle Impact Assessment was performed using the ReCiPe V1.06 method at the midpoint (H) and endpoint (H/A) levels. Crude cardoon oil showed a global warming of 20–55% lower than other vegetable oils (palm, soybean, and rapeseed). In the case of biodiesel production, cardoon-based biodiesel presented a reduction in the impact burden by 12–57% compared to biodiesel based on palm, soybean, and rapeseed. With the use of oil in Polygeneration, a subtle increase in the impact burden was observed, with 13% more impact than the use of Italian power and gas grids.