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In the recent years, the integration of heat storage systems inside building components has been applied for heating and cooling purposes. The implementation of the thermal energy storage inside the building is used to manage and smooth the peak demand. An innovative constructive system including heat storage has been designed to reduce the energy consumption of the HVAC systems, during both heating and cooling periods. It consists of a prefabricated concrete slab with macro-encapsulated PCM inside its hollows. An installation of air ducts allows the air to be forced through the inside of the slab and therefore enhancing the heat exchange with the PCM. The operational mode during summer lies in solidifying the PCM during the night time and using the cold stored as a cooling supply during the day. Moreover, a solar air collector is installed for the winter mode, where the heat from the solar radiation is used to melt the PCM and cover part of the heating demand. The objective of this study is to analyse the benefits of this new system and to quantify its potential in reducing the energy consumed both for heating and cooling. The work partially funded by the Spanish government (ENE2011-28269-C03-01 and ULLE10-4E-1305)

Most predictive models forecast significant upward displacement of forest species due to increases in temperatures, but not all the species respond in the same way to changes in climate. In temperate or mountain systems, biotic competitive interactions drive species distributions, and responses to climate change will ultimately depend upon productive and demographic processes such as growth, recruitment and mortality. We parameterized and used an individual-based, spatially explicit model of forest dynamics (SORTIE-ND) to investigate the role of species-specific differences in juvenile performance induced by climate change (juvenile growth and recruitment ability) in the dynamics of mixed forests located in the montane-subalpine ecotone of the Pyrenees. We assessed this role for two types of forests composed of three species with differing light requirements and sensitivity to climate change: (1) a mixed forest with two shade-intolerant pines (Pinus uncinata and Pinus sylvestris) and (2) a mixed forest composed by a shade-intolerant pine and a shade-tolerant fir (Abies alba). Our results show that for species with similar light requirements (i.e., both pines), small differences in sapling growth response to climate change can lead to significant differences in future species composition (an increase in P. sylvestris growth of 10% leads to an increase in its abundance from 42% to 50.3%). Conversely, in pine-fir forests, shade-tolerance results more decisive than climate-induced changes in growth in driving the future forest composition. The authors are particularly grateful to M. Beaudet, M.J. Papaik, L. Murphy, and C.D. Canham for their help during parameterization of the model and for technical support. We acknowledge W.F.J. Parsons (CEF) for helpful comments and English corrections on an earlier version of the manuscript. Financial support for this study was provided by the Spanish Ministry of Science and Innovation through the projects Consolider-Ingenio Montes (CSD2008-00040), DINAMIX (AGL2009-13270-C02) and RESILFOR (AGL2012-40039-C02-01), and by the European Commission through the Marie Curie IRSES project “NEWFORESTS”. LC was supported through a Ramon y Cajal contract (RYC-2009-04985), while the Spanish Ministry of Education provided AA with support through a predoctoral grant (FPU Programme – AP2007-01663).

The incorporation of recycled materials in concrete as a partial replacement of cement is becoming an alternative strategy for decreasing energy-intensive and CO2 emissions imputable to the cement manufacture, while investigating new potential uses of such multifunctional materials for environmental sustainability opportunities. Therefore, low-cost and worldwide availability of by-products materials is being assessed for sensible heat thermal energy storage applications based on cementitious materials. A greater concern is especially required focusing on the thermal stability of cement paste under high temperature cycled conditions. Moreover, compatibility between cement type and supplementary cementitious materials is determinant for the proper performance reliability. In this study, benchmark cement types were selected, i.e., ordinary Portland and calcium aluminate. Six supplementary cementitious materials were added to both types of cement in a content of 10 % and 25 %. Thermo-mechanical properties were studied before and after 10 thermal cycles from 290 to 650 ◦C. Results after thermal cycling showed that calcium aluminate cement paste mixtures maintained their integrity. However, most ordinary Portland cement paste mixtures were deteriorated: only mixtures with 25 % cement replacement with chamotte, flay ash, and ground granulated blast furnace slag remained without cracks. Calcium aluminate cement paste mixtures obtained the highest compressive strength, for partial replacement of cement with 10 % of chamotte, ground granulated blast furnace slag, and iron silicate. The incorporation of supplementary cementitious materials did not increase the thermal conductivity. This work was partially funded by the Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31 - MCIU/AEI/FEDER, UE) and by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) (RED2018-102431-T). The authors at University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme and by the Italian project ‘SOS-CITTA’ supported by Fondazione Cassa di Risparmio di Perugia under grant agreement No 2018.0499.026. Laura Boquera acknowledgments are due to the PhD school in Energy and Sustainable Development from University of Perugia. Laura Boquera would like to acknowledge the financial support provided by UNIPG – CIRIAF InpathTES project. The authors also thank the companies that provided the material to make possible this experimental research: Arciresa, Abrasivos Mendiola EDERSA—Masaveu Industria, General Admixtures S.p.A, Mapei, Ciments Molins industrial, and Promsa for the material supplied in this research. Financial support of the UNIPG-CIRIAF team has been achieved from the Italian Ministry of University and Research (MUR) in the framework of the Project FISR 2019: “Eco Earth” (code 00245) and it is gratefully acknowledged.

The Pacific Small Island Developing States (SIDS) are among the most vulnerable to the impacts of climate change. Besides, they are some of the most dependent on imported petroleum products in the world, the use of renewable energy (RE) can help minimize the economic risk associated with the price volatility of fossil fuels. The region is increasingly adopting renewable energy (RE) targets and policies. Successful examples of RE deployment in the Pacific SIDS exist; however, many barriers persist and prevent the use of the region’s RE resources in a larger scale. Challenges for RE deployment in islands can be grouped in six categories: i) lack of RE data, ii) need for policy and regulatory frameworks, iii) scarcity of financial opportunities, iv) lack of human resources, v) costly infrastructure, and vi) socio-cultural impediments. Based on a survey conducted among main stakeholders in the region, within the framework of the Pacific Region Capacity Building Initiative of the International Renewable Energy Agency (IRENA) carried out in cooperation with the Secretariat of the Pacific Community (SPC), this paper identifies the specific characteristics of these challenges in the context of the Pacific SIDS, provide a qualitative assessment and identifies recommendations to overcome these challenges. The authors would like to acknowledge Mr. Dolf Gielen form the Secretariat of the International Renewable Energy Agency. The authors from the University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123). The work is partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER).

AbstractQuestionsHow do thermal migration distance and extreme cold events affect seedling emergence and survival in assisted migration schemes in the sub‐Mediterranean context? What role does plant provenance play? Can biotic interactions such as nurse effect of the overstorey and shrub layer buffer the negative responses to plant translocation? Are any of these effects species‐specific?LocationThree pinewoods in the Catalan Pre‐Pyrenees, northeast Iberian Peninsula.MethodsWe used a replicated field trial to test the early years establishment of two contrasted provenances of four Quercus species (Q. coccifera, Q. ilex, Q. faginea and Q. pubescens) that were sown and planted along gradients of elevation and understorey microsite conditions in sub‐Mediterranean pinewoods. Seedling responses to translocation were evaluated through seedling emergence, seedling survival and re‐sprouting after dieback events according to seedling provenance, thermal migration distance, extreme cold events and microenvironment.ResultsThe study reports high success of both the planting (with an overall 76.3% of initial 3‐yr survival) and sowing (with an overall 50% of seedling emergence) experiments. The results show that: (1) the thermal migration distance and the occurrence of extreme cold events have strong effects on the responses of the translocated species (particularly the evergreen oaks); (2) the forest overstorey plays an important role in attenuating the negative effects of thermal migration distance on seedling survival; and (3) these responses are species‐specific. The evergreen Quercus species showed more evidence of high ecotypic differentiation in terms of cold tolerance, enabling local provenances to respond better to translocation. In contrast, marcescent species, showed high phenotypic plasticity that led to a better overall establishment success.ConclusionThe implementation of assisted migration is a feasible option to increase the diversity and resilience of the sub‐Mediterranean pinewoods. Assisted migration programmes should manage risks by thoroughly considering thermal migration distances and the occurrence of extreme cold events when selecting species and seed sources, since Mediterranean tree species show different strategies regarding adaptation to cold. Programme managers should also consider the advantage of planting/sowing under relatively closed canopy to buffer some of the negative responses associated with translocation.

Abstract This review summarizes and organizes the literature on life cycle assessment (LCA), life cycle energy analysis (LCEA) and life cycle cost analysis (LCCA) studies carried out for environmental evaluation of buildings and building related industry and sector (including construction products, construction systems, buildings, and civil engineering constructions). The review shows that most LCA and LCEA are carried out in what is shown as “exemplary buildings”, that is, buildings that have been designed and constructed as low energy buildings, but there are very few studies on “traditional buildings”, that is, buildings such as those mostly found in our cities. Similarly, most studies are carried out in urban areas, while rural areas are not well represented in the literature. Finally, studies are not equally distributed around the world.

Sustainability trends for buildings require new construction systems to foster energy efficiency and environmentally friendly buildings. Green roofs are interesting construction systems because they provide both aesthetic and environmental benefits. This paper continues a long-term research in order to evaluate and improve the thermal behaviour and sustainability of extensive green roofs. Simultaneously this research provides experimental data for specific Mediterranean continental climate conditions. The experiment consists in evaluating the energy consumption and thermal behaviour of three identical house-like cubicles located in Puigverd de Lleida (Spain), where the only difference is the roof construction system. The roof consists of a conventional flat roof with insulation in the reference case, while in the other two cubicles the insulation layer has been replaced by a 9 cm depth extensive green roof (comparing recycled rubber crumbs and pozzolana as drainage layer materials). The electrical energy consumption of a heat pump system was measured for each cubicle during 2012 and part of 2013. Both extensive green roof cubicles show less energy consumption (16.7% and 2.2%, respectively) than the reference one during warm periods, whereas both extensive green roof systems present a higher energy consumption (6.1% and 11.1%, respectively) compared to the reference cubicle during heating periods. This work was partially funded by the Spanish Government (ENE2011-28269-C03-02 and ULLE10-4E-1305), in collaboration with the companies Gestión Medioambiental de Neumáticos S.L (Polígon Industrial Piverd s/n, Maials.) and Soprema and with the City Hall of Puigverd de Lleida. Moreover, the research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007–2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE). The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). Julià Coma would like to thank the Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya for his research fellowship.