Life Cycle Assessment of a Commercially Available Organic Rankine Cycle Unit Coupled with a Biomass Boiler

Abstract

Organic Rankine Cycle (ORC) turbogenerators are a well-established technology to recover from medium to ultra-low grade heat and generate electricity, or heat and work as cogenerative units. High firmness, good reliability and acceptable efficiency guarantee to ORCs a large range of applications: from waste heat recovery of industrial processes to the enhancement of heat generated by renewable resources like biomass, solar or geothermal. ORC unit coupled with biomass boiler is one of the most adopted arrangements. However, despite biomass renewability, it is mandatory to evaluate the environmental impact of systems composed by boilers and ORCs taking into account the entire life cycle. To this purpose, the authors perform a life cycle assessment of a commercially available 150 kW cogenerative ORC unit coupled with a biomass boiler to assess the global environmental performance. The system is modelled in SimaPro using different approaches. Results show that the most impacting processes in terms of CO2 equivalent emissions are the ones related to biomass production and organic fluid leakages with 71% and 19% of the total. Therefore, being fluid release in the environment high impacting, a comparison among three fluids is also performed. Analysis shows that adopting a hydrofluoroolefin fluid with a low global warming potential instead of the hydrocarbon fluid as already used in the cycle guarantees a significant improvement of the environmental performance.

A review of conventional and exergetic life cycle assessments of organic Rankine cycle plants exploiting various low-temperature energy resources

“…Although some environmental impact points were scored by the integration, their effects were offset by other production and transportation processes of the ORC component. Furthermore, Stoppato and Benato ( Stoppato and Benato, 2020 ) investigated the environmental impacts and the main activities contributing to these impacts during the life of a biomass-fired ORC CHP plant located in Italy. The inventory analysis employed real data of the operational plant and standard databases such as the Ecoinvent 3.…”

Spraying Cooling System for PV Modules: Experimental Measurements for Temperature Trends Assessment and System Design Feasibility

“…Later on, the same researchers performed an economic-environmental evaluation of both passive and active cooling techniques [7,56] using as test case a 30 kW PV system and cooling technologies presented in the literature by several other researchers. The environmental analysis is based on the Life Cycle Assessment approach, the most accredited assessment method at the international level for the quantification of damage and its outcomes (see, e.g., in [57,58]). Results show that, from a technical and economic point of view, the most viable passive cooling system is the one using air as coolant on the backside surface of the PV panel; but, to this surface aluminum fins need to be attached to increase the thermal exchange surface.…”

Organic Rankine Cycle for Energy Recovery System

“…This book contains the successful invited submissions [1][2][3][4][5][6][7][8][9] to a Special Issue of Energies entitled "Organic Rankine Cycle for Energy Recovery System", focusing on a modern technology committed to energy saving and thus capable of producing positive environmental outcomes. Indeed, the organic Rankine cycle (ORC) is a thermodynamic concept already demonstrated as an engineering viable solution for waste heat recovery systems.…”

“…A representative example of an ORC plant integrated with a biomass boiler is provided by Stoppato et al [6], where the main focus is on the LCA technique application and the calculation of carbon footprint.…”