Cumulative Energy Demand Research Articles

Environmental performance of the innovative, patented mixing system in an agricultural biogas plant based on LCA approach

Renewable energy production in biogas plants seems to be recognised in literature from the environmental perspective. However, innovative technologies are still launched to improve energy efficiency. In this perspective, the authors developed the patented hybrid pump to improve the yield of methane production and reduce the environmental impact of renewable energy production. This research assesses the environmental performance of an innovative, patented hybrid pump designed for mixing the input of anaerobic digestion of pig slurry, based on the Life Cycle Assessment (LCA) approach. The comparative environmental analysis of two different mixing systems installed in the pilot biogas plant was conducted on the basis of the selected impact categories. The application of innovative mixing technology with a hybrid pump increased the percentage yield of methane in biogas from slurry by about 10% compared to a conventional hydraulic pump. The application of a hybrid pump in the tested biogas plant reduced the Cumulative Energy Demand (CED) ratio by almost 30% compared to a conventional hydraulic pump. A similar level was obtained for other environmental impact ratios in terms of global warming potential, abiotic depletion of fossil fuels, human toxicity, acidification, and eutrophication.

Industrial hemp (Cannabis sativa L.) for phytoremediation: Energy and environmental life cycle assessment of using contaminated biomass as an energy resource

The objectives of this study were to assess the environmental impacts of growing industrial hemp (Cannabis sativa L.) on the phytoremediation of heavy metal-polluted soil and using contaminated biomass as an energy resource. A life cycle assessment approach was adopted to evaluate the cumulative energy demand and climate change impact of using contaminated biomass for energy generation under 4 different scenarios. The industrial hemp supply chain scenarios include analyses of different subsystems (industrial hemp cultivation, seed processing, anaerobic digestion and biomass incineration for electricity generation) and different contaminated products harvested (seeds and straw, dried whole industrial hemp and fresh biomass for silage). As confirmed by a Monte Carlo simulation, the two scenarios that included anaerobic digestion and/or incineration of the contaminated biomass were the most energy-efficient and environmentally sustainable systems and obtained primary energy savings of 25.3 and 36.8 GJ ha−1, respectively, while avoiding emissions of 579 and 641 kg CO2e per reclaimed hectare, respectively. These results demonstrate the great potential of using contaminated areas for bioenergy (electricity) production while decreasing the exploitation of natural resources and pollutant emissions into the environment. Moreover, phytoremediation technologies combined with the energy valorization of biomass are recommended to change unproductive contaminated soils into exploitable and productive areas.

Characterising municipal solid waste to analyse life-cycle energy demand and emissions

A life-cycle assessment (LCA) of waste management in Pyongyang, the Democratic People's Republic of Korea was undertaken using a characterisation-based method to analyse cumulative energy demand and energy-related carbon dioxide emissions. The study showed that characterising waste fractions by composition, proportion, water content and heating value rather than simply mass was more effective for energy-related analysis in LCAs. The results indicated that the energy demand and emissions indicators could be used as appropriate proxies of the environmental impacts in life-cycle phases, since they were closely related. The results also revealed that waste incineration could result in energy credit to the national electricity mix, while waste landfill needed to be replaced with sanitary landfill and/or switched to incineration with energy recovery to be more sustainable.

Life cycle assessment and cost analysis for copper hydrometallurgy industry in China

Understanding the environmental and economic impacts of copper hydrometallurgy throughout the whole life cycle is necessary for sustainable development of the copper industry. In this study, the environmental impacts and economic costs throughout the two major copper hydrometallurgical routes in China, including heap leaching and heap-agitation leaching, are analyzed and compared using the life cycle assessment (LCA) and life cycle cost (LCC) technique. The life cycle inventory compiled from the annual statistics of the Muliashi Copper Mine, and the data regarding energy and materials process are based on the GaBi databases. The environmental impacts are quantified into 12 indicators. The results show that compared with heap leaching route, heap-agitation leaching route reduces 36.8% of abiotic depletion potential (ADP elements), but increases over half of cumulative energy demand (CED), marine aquatic ecotoxicity potential (MAETP) and human toxicity potential (HTP). Furthermore, the stage of electrowinning and agitation leaching contributes the largest environmental impact to heap leaching and heap-agitation leaching route, respectively. This is mainly due to huge consumption of electricity and sulfuric acid. The analysis of economic cost reveals that heap leaching route needs internal cost of $3225/t Cu and external cost of $426/t Cu. Compared with heap leaching route, heap-agitation leaching route increased the internal and external cost by 18.9% and 54.2%, respectively. But the economic return from heap-agitation leaching is double that from heap leaching. Together, these results indicate heap-agitation leaching has a larger environmental impact and higher economic benefit than heap leaching, which is helpful for the government to design ecological compensation policies in the balance between ecological environment and economic development.

Life cycle assessment of a short-rotation coppice willow riparian buffer strip for farm nutrient mitigation and renewable energy production

As agricultural activity intensifies across Europe there is growing concern over water quality. Agricultural run-off is a leading cause of freshwater degradation. Simultaneously there is a continually increasing drive to promote renewable energy and reduce greenhouse gas emissions. Willow coppice planted as a riparian buffer has been suggested as a solution to help mitigate these problems. However, there is limited research into the use of such a system and several key knowledge gaps remain, such as, the energy ratio of the system is not known, and a fully harvested site has yet to be analysed in the literature. The aim of this research is to fill these knowledge gaps to help inform agri-environmental policy. To do this a life cycle assessment was carried out on an established willow buffer system, considering the global warming potential, eutrophication potential, acidification potential and cumulative energy demand impact categories, alongside the calculation of the energy ratio. To our knowledge it is the first site to be fully harvested and for which a full life cycle assessment has been carried out. The willow was combusted to fuel a district heating system. Key results showed emissions of 4.66 kg CO2eq GJheatout−1 and 0.01 kg SO2eq GJheatout−1, both of which are significant reductions compared to an oil heating system (95% reductions for both impact categories). The system also resulted in the permanent nutrient removal of 55.36 kg PO43−eq ha−1 yr−1 and had an energy ratio of 17.4, which could rise to 64 depending on the harvest method.

Environmental hotspots and greenhouse gas reduction potential for different lithium-ion battery recovery strategies

The ever-growing demand for lithium-ion batteries (LIBs) and the shortage of metal minerals have led to urgent needs in battery recycling. Current recycling technologies cannot keep up with the exaltation of the LIB market and meet UN Sustainable Development Goals (SDGs). A holistic assessment of environmental tradeoffs is critical for recycling technological innovation. We divided traditional hydrometallurgy and pyrometallurgy recycling into three generalized phases and identified stepwise environmental “hotspots” among different LIB recycling techniques using life cycle assessment (LCA). Greenhouse gas (GHG) emission and cumulative energy demand (CED) vary among recycling approaches from 67 to 286 kg carbon dioxide equivalent (CO2eq) and 1164–4349 MJ, respectively, for reproducing 1 kg LCO cathode from recovered cobalt. Comparatively, a direct “cathode-healing” process emits 21–154 kg CO2eq and utilizes 267–2251 MJ to regenerate 1 kg LCO. When substituting the stepwise recycling with the direct approach, 127 of 162 modeled scenarios show GHG reduction. Up to 36.5 million metric tons of CO2eq may be reduced if 100% stepwise recycling is replaced by the green direct approach by 2025. Our study provides insights into optimizing LIB recovery technologies to minimize environmental impacts and offer quantitative evidence for sustainable management and technological innovation for spent LIB recovery.

Environmental assessment of copper production in Europe: an LCA case study from Sweden conducted using two conventional software-database setups

This study focuses on the environmental assessment of European copper production. Life cycle assessment is applied to analyse copper cathode production in Sweden, including its mining (an open-pit mine) and refining (pyrometallurgy), and using two combinations of software and databases: SimaPro software with ecoinvent database and GaBi software with GaBi database. The results are compared with results from other case studies from literature. A cradle-to-gate LCA was conducted considering 1 tonne of copper as functional unit. The inventory for the foreground system was elaborated using primary data gathered by the staff from the mine, the concentrator and the smelter. For the background data, LCA databases are used considering datasets for the Swedish market whenever possible. As the smelter has multiple useful outputs, economic allocation was applied at the inventory level. The calculation method CML-IA baseline 3.5 was considered for both combinations of software and database, reporting all the impact categories of the method plus the Cumulative Energy Demand. The inventory of the system and the main environmental hotspots were presented, such as the explosives for blasting (due to their supply chain) or the electricity used in the concentrator. The results obtained with the two combinations of LCA software and databases yield large differences for categories such as abiotic depletion (7.5 times higher for SimaPro and ecoinvent), possibly due to differences in the system boundaries of the databases and the characterisation factors of the method. Although the case study has a relatively high cumulative energy demand (140/168 kMJ/tonne Cu) compared to other mines, its performance in global warming (3.5/4.7 tonne CO2eq/tonne Cu) is much better due to the low greenhouse gas emissions from electricity, which shows that the electricity mix is a key aspect. The environmental performance of mining depends partially on the specific conditions of the deposit, e.g., the ore grade and the mining type. LCA practitioners should consider the potential different results that can be obtained using different combinations of software and database and exert caution when comparing cases, especially for abiotic depletion, human toxicity and ecotoxicity categories. Finally, the use of renewable energies can be key to improve the environmental sustainability of copper production.

Country-specific carbon footprint and cumulative energy demand of metallurgical grade silicon production for silicon photovoltaics

The photovoltaic (PV) industry requires high-quality silica sand to produce metallurgical-grade silicon (MG-Si) for silicon PV (Si PV). However, high-quality deposits are scarce, and using lower-quality resources may increase the carbon footprint and cumulative energy demand (CED) of Si PV modules. The environmental impact of quartz mining and silica sand extraction for PV has not been updated in over 15 years. It's not representative of current methods used for low-quality sand and is not country-specific. As a result, PV production's environmental impact might be underestimated. We used life-cycle assessment to evaluate the carbon footprint and CED of quartz mining, silica sand extraction, and MG-Si production for high-quality (> 98% silica), industrial-grade (95% silica), and low-quality (65% silica) quartz deposits, which are necessary to calculate Si PV's energy and carbon payback time. The carbon footprint per metric ton of silica sand extraction increased from 22.7 kg CO2eq for high-quality quartz to 47.9 for industrial-grade and 86.7 for low-quality. China currently uses foreign industrial-grade quartz but plans to use low-quality domestic resources, which could increase the carbon footprint of producing one kg MG-Si from 12.1 to 16.5 kg CO2eq. The CED could increase from 188 to 286 MJ. We also investigated illegal mining's environmental impact. The carbon footprint and CED of MG-Si production decreased by 26 to 60% for illegal mines compared to legal mines. Illegal MG-Si production can be cheaper and have a lower carbon footprint, and therefore, third-party-supply-chain verifications are essential to ensure that PV doesn't contribute to the problem.

Sustainability Evaluation of Pyrolysis of Waste Mattresses: A Comparison with Alternative End-of-Life Treatments

There is a major push by governments and value chain partners to move towards circular options for difficult-to-recycle post-consumer products such as waste mattresses.[1] In the Netherlands alone ~1.5 million mattresses are discarded yearly, of which majority (>60%) is incinerated.[2] A sustainable solution to recycle waste mattresses is required to enable the Dutch industry meet the circular economy goals set by the Dutch government.[3] This paper shares major findings from the screening level life cycle assessment (LCA) of four End-of-Life (EoL) options for post-consumer mattresses: landfill, incineration with energy recovery, pyrolysis and mechanical recycling using powdering. The LCA was an important work package of a technology development project with the objective to quantify potential sustainability benefits of the pyrolysis of waste mattresses.[4] The emphasis of the pyrolysis process is on product recovery as chemical feedstock. The study showed that pyrolysis is a better option than incineration in terms of greenhouse gases ( GHG) and cumulative energy demand (CED) for all the studied cases. Base case analysis showed that pyrolysis of waste mattresses can save approximately 526 kg CO2-eq. and approximately 5.1 GJ (24% savings) CED per ton waste mattresses compared to incineration. Finally, the study concluded that mechanical recycling can either be better or worse than pyrolysis depending on the processes and quality of recycled material.

Effects of deposition parameters on cumulative energy demand for Cold Metal Transfer additive manufacturing processes

This paper proposes a methodology that can be used to assess the effects of variations in the process parameters on the energy consumption of a Cold Metal Transfer (CMT) additive manufacturing process. The analysis was carried out at the process level and then extended to cradle-to-gate system boundaries. A thin-walled component was considered as a demonstrative case study. The results demonstrate that any variation in deposition process parameters (namely, the wire feed speed and the travel speed) affects not only the energy requirements related to the deposition process itself, but also the material deposition efficiency and the cradle-to-gate cumulative energy demand.

An appraisal of the cradle-to-gate energy demand and carbon footprint of high-speed steel cutting tools

The awareness of the environmental impact of the manufacturing sector has increased over the last few decades. This paper presents the results of an LCA-based approach used to evaluate the production of a threading tool (i.e., an M10 × 1.25 spiral point tap) made of high-speed steel. The cumulative energy demand and CO2-equivalent emissions have been quantified throughout the entire tool manufacturing process. Both the pre-manufacturing steps and the upstream/downstream flows of the used material have been accounted for, considering cradle-to-gate (plus end-of-life) system boundaries. The results show that the share of primary energy employed to produce the tool is mainly imputable to the manufacturing processes. Therefore, this analysis could contribute to fostering the development of structured assessment frameworks that would allow cutting tool manufacturers to identify the weak points of their production routes to be optimized.

Comparison between the mechanical properties and environmental impacts of 3D printed synthetic and bio-based composites

The present work aims at studying both the mechanical properties and environmental impacts of two 3D printable composites materials: glass fiber reinforced polyamide (GlassPA) and bio-based hemp fiber reinforced polylactide (HempPLA). Hence, this study aims to provide a comprehensive overview of the two considered materials, supporting the sustainable development of industrial additive manufacturing processes. To this purpose, tensile specimens were produced using a Fused Deposition Modeling process and then tensile tested to evaluate the mechanical properties of the printed materials. The environmental impacts of both GlassPA and HempPLA were investigated using the Life Cycle Assessment methodology; a cradle to gate approach was chosen to evaluate all the relevant input of the tensile specimens production. Mechanical tests showed that synthetic composite is characterized by higher strength and stiffness values than the bio-based composite. However, HempPLA results in noticeably lower environmental impacts than GlassPA in terms of Cumulative Energy Demand and Global Warming Potential indicators, proving to be a feasible alternative to glass fiber reinforced polymers in application with low load conditions.

Reducing the environmental impacts of aluminum extrusion

The aluminum extrusion industry is growing rapidly; however, there has been little work on quantifying or reducing extrusion's environmental impacts. This article first derives cradle-to-gate cumulative energy demand, greenhouse gas emission, and cost models for direct aluminum extrusion using data collected from extrusion companies, life cycle inventory measurements (e.g., electricity demand) from our own case studies, and physics-based extrapolations. These models show there is significant scope for increasing both the process energy and material efficiency; however, only increasing the material efficiency will lead to significant environmental benefits and cost savings. Subsequently, an alloy-shape-application material flow analysis of the 2018 North American extrusion industry is conducted to highlight opportunities for improved material utilization throughout the supply chain. Material flow data were collated from existing academic and gray literature in addition to semi-structured interviews with North American extrusion experts. The material flow analysis reveals that around 40% of all aluminum cast into extrusion billets is scrapped before completion in a fabricated product, which increases the cost of the fabricated profile by approximately 16% and the greenhouse gas emissions and cumulative energy demand by approximately 40%. Most of this scrap is created by removing structural and surface finish extrusion defects that are inherent to the current process. Process adaptations that might reduce the material scrapped due to these defects are identified and discussed. Even a 10% reduction in extrusion process forming scrap could save the North American (U.S. and Canada) extrusion industry 270–311 million USD per year and prevent the release of 0.5–2.3 Mt.CO2eq annually.

Energy and environmental impacts of a 37.57 MW dc ground-mounted large-scale photovoltaic system in Malaysia: A life-cycle approach

This paper estimated the environmental performance and primary energy consumption of a newly installed large-scale solar photovoltaic system of 37.57 MW dc in Bidor, Malaysia using the process-based life-cycle assessment approach. The mid-point and end-point impact categories were evaluated, and seven relevant indicators related to energy and global warming were determined. The global warming impact and energy payback time obtained were 30.95 g CO2-eq/kWh and 3.43 years, respectively. Furthermore, the global warming impact mitigation potential attained was 811 kilo metric tonne (ktonne) CO2-eq throughout the system lifetime. Analyses of contribution, sensitivity and uncertainty were performed to i) identify photovoltaic system components that substantially consumed primary energy and impacted the environment, ii) evaluate the effect of four key parameters, namely irradiation, performance ratio, system lifetime and electricity mix on the energy and global warming-related indicators, and iii) estimate the uncertainty range of the evaluated indicators. The results highlighted that the main contributor to the indicators is the photovoltaic module. Other significant contributors are the civil work and operational and maintenance but the contribution from these components is much lower than the photovoltaic module. Besides that, the cumulative energy demand, energy return on investment, global warming impact and global warming impact mitigation potential showed an improvement when extending system lifetime from 15 to 40 years, i.e. from 0.8136 to 0.3677 MJ, 4.61 to 11.25, 55.37 to 24.99 g CO2-eq/kWh and 407.36 to 1055.78 g CO2-eq respectively, except for energy payback time and global warming payback time, i.e. from 3.26 to 3.55 years and 1.42 to 1.71 years respectively.

Group contribution‐based LCA models to enable screening for environmentally benign novel chemicals in CAMD applications

AbstractThis study considers the development of suitable models for the estimation of life cycle assessment (LCA) indices of organic chemicals. Unlike state‐of‐the‐art models, the tools developed here correlate LCA indices with the molecular composition according to the well‐established group contribution (GC) approach. The LCA indices considered here are global warming potential, cumulative energy demand, and Eco‐Indicator 99. The model development uses data from existing LCA databases, where each material is associated with its cradle‐to‐gate LCA metrics. A variety of regression and nonregression methodologies are recruited to achieve the optimum correlation. GC models can be used to screen for molecules with optimal and/or desirable properties, using appropriate molecular design synthesis algorithms. In this framework, the models developed here are linked to the design algorithm to enable the consideration of LCA features together with other properties, for the design of environmentally benign liquid–liquid extraction solvents.

Analysis of the water–energy–greenhouse gas nexus in a water supply system in the Northeast of Brazil

In recent years, water utilities have been under pressure to increase the efficiency of their processes, mainly due to the decrease in water availability and the need to increase environmental sustainability in their processes. Leak reduction is clearly an important part of sustainable management in the water industry, and its impacts should be assessed with a broader environmental protection objective. This study aimed to present an environmental and energy assessment of the water supply system (WSS) in Caruaru City, northeast of Brazil, for different levels of water loss. This research is one of the first to assess the environmental impacts of a WSS in Latin America. Primary data adopted for preparing the inventory were provided by the water utility, and modeling and analysis were performed with the SimaPro 8.0® program. Cumulative energy demand (CED) was used to track the energy consumption of the system’s life cycle. Greenhouse gas (GHG) emissions were calculated through the IPCC GWP 100a method with emissions expressed as CO2-Eq. The data sets from life-cycle inventories were used from the Ecoinvent 3.1 database. Four scenarios with different levels of water loss were analyzed. Scenario S0 was represented with the real conditions of the system, whereas the others considered hypothetical indices. The percentages proposed for Scenarios S1, S2, and S3 were based on indices that indicate good loss rate in the distribution network for the Brazilian reality (25%), reduction by half of loss rates, and excellent loss rates for the water pipeline system (5%) and distribution network (10%). The analysis of the processes’ contributions showed that the electricity consumption of the pumping systems of water mains represented the greatest environmental impact in all scenarios. The most efficient scenario would result in a 52% reduction in the emission of GHGs, demonstrating that the increase in the hydraulic efficiency of the distribution networks represents a significant opportunity to reduce the environmental impacts of the processes.

Life Cycle Assessment of Biocement: An Emerging Sustainable Solution?

Microbially Induced Calcium Carbonate Precipitation (MICP) is a natural biocementation that takes place in corals, stromatolites and beach rocks. In recent years, researchers have explored the emulation of this process as a sustainable alternative of engineered cement. Although the natural process is undoubtedly sustainable, its engineered variant deviates substantially from the natural process. In this paper, we investigate the environmental and economic performance of the engineered biocementation process vis-à-vis present manufacturing of calcium carbonate. SimaPro 8.0 software and the Ecoinvent V2.2 database were used for materials inputs and AUSLCI along with Cumulative Energy Demand 2.01 software were used for carbon footprint and eutrophication potential. Our results show that different metabolic pathways of MICP have considerably varying environmental impact. We observe that nature performs MICP sustainably at ambient conditions and geological time scales utilizing naturally occurring sources of carbon and calcium at micromoles concentrations. Due to the mandate on duration of construction projects, highly purified reactants in a high concentration are used in the engineered process. This has a negative environmental impact. We conclude that the sustainability of engineered MICP is directly impacted by the metabolic pathway of bacteria as well as the purity of the input chemicals. A few biotic processes are superior to the present industrial process for manufacturing calcium carbonate if ingredients of laboratory grade purity are replaced by industrial grade products. A bigger dividend can be obtained by introducing industry by-products as nutrients. The results of this study help to direct future research for developing sustainable biocement for the construction industry.

Life Cycle Assessment of Ethiopian Cement Manufacturing: A Potential Improvement on the Use of Fossil Fuel in Mugher Cement Factory

The use of imported fuel in the Ethiopian cement industry increased the cost of production and the environmental burden, necessitating intervention. The greenhouse gas (GHG) emission, energy usage intensity, and resource exploitation of Ethiopian cement production were evaluated using the life cycle impact assessment (LCA) tool, aiming to recommend improvements. The LCA study used cumulative energy demand (CED) and Intergovernmental Panel on Climate Change (IPCC) 2006 life cycle impact assessment (LCIA) methods. For the case study of Mugher cement factory (MCF), the results on energy use intensities showed 3.74, 3.67, and 2.64 GJ/ton of clinker, Ordinary Portland cement (OPC), Pozzolana Portland cement (PPC), respectively. The result revealed MCF's energy use intensity was within the global range of 3.32 to 5.11 GJ/ton of cement production using similar kiln technology. The results on the GHG emissions were 0.87, 0.84, and 0.59 tons of CO2-equivalent/ton of clinker, OPC, and PPC, respectively. Process emissions accounted for 60% of overall CO2 emissions, with energy-related emissions accounting for the remaining 40%. CO2 emissions of MCF are below the global limit of 0.9 tons/ton of clinker, where all energy sources are fossil fuels. However, it is higher than the 0.65 ton/ton of clinker from a moderate rotary kiln in China. MCF used 70% of its total energy sources from imported fossil fuels, and transportation of the imported fuel added 1.2% CO2 to total emissions. A suggested fossil fuel use improvement scenario for MCF, where coffee husk replaces 50% of the imported coal improved the energy intensity, GHG emissions, and total cost of coal in clinker production by 1.2%, 14%, 36%, respectively.

Energy analysis and life cycle assessment of a thermal energy storage unit involving conventional or recycled storage materials and devoted to industrial waste heat valorisation

Any system intending to improve the environmental performances of a process should be assessed by a Life Cycle Assessment. This work draws up the environmental profile of the heat provided by a storage system recovering industrial waste heat at high temperature (500 °C) through 5 selected indicators: Cumulative Energy Demand, Global Warming Potential, abiotic depletion potential, particle matter and freshwater eutrophication. The calculated indicators were compared to those of the fossil fuel substituted by the recovered heat, that is to say natural gas, and proved to be reduced. Then, the environmental payback times were calculated; and an energetic profitability evaluation by the Energy Returned on Investment expanded on the profile. Besides, the influence of operating conditions variations was investigated through a parametric study. An optimal number of cycles to provide the same amount of energy may be defined, as a compromise between the abiotic resource depletion potential reduction with smaller tanks performing more cycles and the energy returned on investment deteriorated with the operational energy consumption increased due to higher pressure drop with smaller tank diameter. The most rewarding environmental performances concerned the Cumulative Energy Demand, Global Warming Potential indicators of the provided heat, about 1.2 kgCO2-eq and 65 MJ-eq per kWh (payback time lower than 3 months), and the Energy Returned on Investment that doubled compared to natural gas, e.g. reached a value of 55. The positive effect of using recycled storage materials on the resource depletion indicator were enlightened, notably when the operating conditions strayed from the reference case.

Solar thermal systems for sustainable buildings and climate change mitigation: Recycling, storage and avoided environmental impacts based on different electricity mixes

Solar thermal systems play a pivotal role in the building sector. However, for the development of sustainable energy systems, different parameters should be taken into account. The present article sets out to present a multidimensional approach. To this end, the first part of the article discusses energy policies, placing emphasis on solar thermal applications. The second part of the article is based on Life Cycle Assessment (LCA) and evaluates the environmental performances of a thermal-energy-storage device and other components appropriate for solar thermal systems for buildings. The analysis has been based on global warming potential, cumulative energy demand, ReCiPe and USEtox. The results show that steel and copper are the materials which are responsible for the major part of the storage-device impact. Based on ReCiPe endpoint/with characterisation, steel and copper present 2.2E-03 DALY (damage to human health) and 5.9E-06 (species.yr) (damage to ecosystems). The results show that the metallic components have the highest environmental impacts. By involving recycling, a remarkable reduction in these impacts can be achieved. Issues related to building-integrated solar systems and future prospects are also discussed. Moreover, the avoided impacts due to the use of a solar thermal system instead of using a conventional electric heater for hot water production have been evaluated, considering multiple environmental indicators. The results based on the Spanish electricity mix have been compared with those based on the Italian electricity mix. In both cases, the findings verify that solar thermal systems offer considerable avoided environmental impacts.