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The most recent regulations, as well as the scientific studies, remark the importance of the evaluation of the entire life cycle on building renovations, relative to the environmental impact and economic feasibility, making the Life Cycle Assessment (LCA) the prioritizing analysis. The objective of the study is to develop a simplified methodology for the environmental and economic assessment of residential building renovations with life cycle approach. For this, a script-based tool-kit is developed: the first tool optimizes the thickness of envelope insulation based strategies; the second tool is for the prioritization of strategies by assessing their environmental performance and economic feasibility. In order to follow the objective, the development of the two tools is presented: both tools follow a parallel scheme where the input parameters are required by an excel file and the calculation script provides the results automatically by exporting the results excel file. The evaluation provides the quantification of the relative environmental improvement with the net energy ratio (NER), and the economic feasibility by the financial indicator of internal rate of return (IRR). The tool-kit is applied in a case study of a multifamily residential building. The results show, on the one hand, that the usability of the tool-kit can be determinant in the decision-making of stakeholders; and in the other hand, the importance of carrying out a dynamic assessment, taking into account the variation of the results caused by the uncertain parameters that differ in time. Moreover, the tool-kit can assist the development of cost-effective decarbonisation strategies. Part of the work presented in this paper belongs to the research project PIBA-PUE 2020(PUE_2020_1_0013) funded by the Department of Education of the Basque Government. Moreover, this research work is part of the corresponding author's Doctoral Thesis that aims to investigate the holistic assessment of technical renovation solutions of residential buildings in the Basque Country funded by the Predoctoral Training Programme for Non-Doctor Research Personnel of the Department of Education of the Basque Government (PRE_2021_1_0247).

Acrylic acid, one of the most important monomers, has a wide range of uses e.g. in the paints adhesives, textile finishing, leather processing or super absorbents. The production process from propylene is well known and used at industrial scale in the USA, Europe, and Asia. The present paper focuses on the evaluation of the environmental impact of the acrylic acid production process from propylene. Steam is a major raw material in the process under study, consequently different paths to obtain steam are investigated. The process was simulated using commercial software (Aspen Plus, PROII). A productivity capacity of 50,000 tones/year of acrylic acid has been considered. The environmental assessment, evaluated using Life Cycle Analysis method, depends on the material and energy balances generated by simulations. The present work uses a cradle-to-grave approach. The functional unit, to which all the environmental results for the cases under study are reported, is one tone of acrylic acid produced. The boundaries of the system cover: i) acrylic acid production; ii) upstream processes for example catalyst and molten salt production; steam production using various fuels (e.g. natural gas, anthracite, lignite, heavy fuel oil, light fuel oil and biomass) and iii) downstream processes for example: acrylic acid and acetic acid transport to other chemical plants for further processing. The CML (An LCA method developed by the Center of Environmental Science of Leiden University) 2001 impact assessment method was used for comparison between different case studies. The best value for Global Warming Potential (GWP) e.g. 1094.5 kg CO2-Equiv./tone is obtained when biomass is used to generate the steam required by the process. For other indicators such as Acidification Potential (AP), Photochemical Oxidation Potential (PCOP) and Eutrophication Potential (EP), the best value is obtained when steam is generated from natural gas. A sensitivity analysis of the environmental impact categories using the different combination of natural gas and biomass was also investigated. The study investigates also the association of the post-combustion amine-based carbon capture technologies with the conventional acrylic acid production process. Such association decreases the value of some environmental impact categories (e.g. GWP) while other impact categories are increasing e.g. AP, Human Toxicity Potential (HTP), Terrestrial Ecotoxicity Potential (TETP).

Linear motor drives (LMDs) are well known to provide significant advantages in terms of positioning speed and accuracy over traditional screw drives (SDs), making them better suited for high-speed high-precision machine tools. However, their use in such machine tools is severely limited by their tendency to consume a lot of electrical energy and cause thermal issues, particularly under high cutting loads. A hybrid feed drive (HFD) has recently been proposed as a possible solution to this dilemma. The HFD switches between LMD and SD actuation depending on the mode of the manufacturing operation, thus achieving speeds and accuracies similar to LMDs while consuming much less energy. This paper presents a comparative life cycle analysis (LCA) of the proposed HFD with an LMD as the baseline for the comparison. The functional unit is taken as the production of parts that involve heavy cutting by a small-sized 3-axis precision milling machine for 250 8-hour work days per year over a 12-year first-use life span. Energy savings provided by the HFD during its use phase vis-a-vis the additional energy investments into the HFD at various phases in its life cycle are compared. The analysis predicts a net positive impact, in terms of energy and the environment, for the HFD compared to the LMD under high cutting loads.

Accounting for transportation is an important part of the life cycle analysis (LCA) of beef cattle production because it is associated with energy consumption and greenhouse gas emissions. This paper describes the development and application of a model that estimates energy consumption and greenhouse gas emissions of transport in beef cattle production. The animal transport model is based on the weight and number of animals in each weight category, type of trailer, vehicle, and fuel used. The energy consumption and greenhouse gas emission estimates of animal feed transportation are based on the weight of a truckload and the number of truckloads of feed transported. Our results indicate that a truckload is travelling approximately 326 km in connection with beef cattle production in the study region. The fuel consumption amounts to 24 L of fossil fuel per 1000 kg of boneless beef. The corresponding greenhouse gas emission is 83 kg. It appears from our results that the majority of energy consumption and greenhouse gas emissions are associated with sending the finished cattle to slaughterhouses and bringing feeder cattle to feedlots. Our results point out appreciable reductions in energy consumption and greenhouse gas emissions by changing from conventional fuel to bio-fuel.