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Climate change is considered as one of the biggest threats that humankind is facing nowadays, with environmental, social, and economic consequences. The building sector is facing multiple climate change impacts, which is becoming more and more vulnerable. This is especially true considering that about 35% of the buildings in the European Union (EU) are over 50 years old and the replacement rate of new building in Europe is low. Therefore, it is expected that much of the existing building stock will be affected by several climate change impacts in near future. Specifically, from the building point of view, these impacts can range from a slight rise in the average environmental temperature and humidity levels to extreme and severe events (such as strong wind and floods), changing in most of the cases, the building performance, and thermal behavior. Among the adaptation strategies to climate change, the envelope optimization, whichever climate type, is the most effective way to reduce the building energy dependency and increase the indoor thermal comfort. In this regard, the integration of phase change materials (PCM) into the building envelope can produce a sort of extra thermal capacity to the building, enhancing its overall energy efficiency. Specifically, when PCM is used without any control systems, it means that it is passively contributing to the building thermal comfort, stabilizing the indoor temperature and reducing both cooling and heating demands. Considering that the effectiveness of PCM application over the building envelope is mostly associated with the selection of the appropriate melting temperature and thickness, in the context of climate change, it is expected that the optimal PCM melting point and amount found for the present period will not be optimal for future and vice versa. Therefore, the present book chapter presents a numerical investigation on the effectiveness of PCMs wall implementation as a resilient building refurbishment solution. Specifically, the book chapter aims at proofing the PCM’s capability of being an effective building refurbishment strategy, under historical and future climate conditions. The whole study is based on dynamic building simulations carried out by IDA ICE tool on a typical residential single zone house in Stockholm (Sweden) and Rome (Italy) cities. The results of the simulations highlight that PCM can contribute to a reduction of cooling demand and improve the indoor thermal comfort under both historical and future climate in Stockholm. In addition, PCM results in slight effectiveness in reducing heating loads, and the total annual energy saving is between −1.5% and −2.4% for the historical period and −1.9% and −5.7% for the future one. In Rome, the incorporation of a PCM layer in the building envelope slightly reduces the cooling demand and enhances the indoor thermal comfort, where the total annual energy saving equals to −1.6% for the historical period. Conversely, no beneficial effects in term of annual energy saving have been observed for future climate condition in Rome.

The building provides to the occupants a shelter envelope and comfortable interior climate conditions. Starting from our ancestors, climate directly has great influence on both building design and the corresponding building’s overall energy performance. Nowadays, passive design has been getting popular again for taking advantage of the regional climate to maintain a comfort indoor climate, so as reducing or eliminating the dependence on active systems. Along with the prolonged construction service years, the current appeal of passive design is not only facing historical weather but also the changing future climate. It is undoubted that there is an ever-widening disparity between historical weather patterns and current—not to mention future—climate conditions resulting from anthropogenic changes. Consequently, this chapter focuses on this field and presents a preliminary climate-adaptive design study for urban multifamily buildings at early stage. Special attentions are paid to the indoor thermal comfort and minimum energy use from today to the last part of the twenty-first century. The generated future climate data combined with thermal comfort model assessment has been proposed as a new way of including future climate scenarios in preliminary building design for two representative sites, in Rome, Italy, and Stockholm, Sweden. The existing vulnerability to the expected climate conditions from psychometric analysis indicates that (1) the climate trend in Rome would gradually lead to more failures in the majority of conventional adaptive design measures, as the cooling and dehumidification demands would rise from 5.3% to 23.6%, while the heating and humidification demands would decrease from 27% to 16%, and (2) the climate trend in Stockholm would result in an increased comfort period by exploiting more adaptive design measures, since the heating and humidification demands would be reduced from 67% to 53%. However, the cooling and dehumidification demands would increase slightly from 0% to 1.5%. Accordingly, four main key risks are identified: (1) overheating would become a rising increasing public health threat for buildings in Rome that rely exclusively on natural ventilation; (2) open questions remain for the design team in the area of correct cooling load selection, additional space for the future installation and the effectiveness of current cooling device, etc.; (3) occasional heat waves and gradual rising humidity levels are expected to be a vulnerable topic for conventional lightweight building in Stockholm; and (4) buildings with a heavy heating load would tend to have greater cooling demand, especially those with poor ventilation resources or greater internal gains. In conclusion, it is suggested that envelope optimization, whichever climate type, is one of the most efficient and effective adaptation measures toward future climate conditions. After that, a detailed case study with a new container building is proposed accordingly.

As large energy prosumers in district energy systems, on the one hand, data centers consume a large amount of electricity to ensure the Information Technologies (IT) facilities, ancillary power supply and cooling systems work properly; on the other hand, data centers produce a large quantity of waste heat due to the high heat dissipation rates of the IT facilities. To date, a systematic review of data centers from the perspective of energy prosumers, which considers both integration of the upstream green energy supply and downstream waste heat reuse, is still lacking. As a result, the potentials for improving data centers’ performances are limited due to a lack of global optimization of the upstream renewable energy integration and downstream waste heat utilization. This study is intended to fill in this gap and provides such a review. In this regard, the advancements in different cooling techniques, integration of renewable energy and advanced controls, waste heat utilization and connections for district heating, real projects, performance metrics and economic, energy and environmental analyses are reviewed. Based on the enormous amount of research on data centers in district energy systems, it has been found that: (1) global controls, which can manage the upstream renewable production, data centers’ operation and waste heat generation and downstream waste heat utilization are still lacking; (2) regional climate studies represent an effective way to find the optimal integration of renewable energy and waste heat recovery technologies for improving the data centers’ energy efficiency; (3) the development of global energy metrics will help to appropriately quantify the data center performances.

The deployment of containers as building modules has grown in popularity over the past years due to their inherent strength, modular construction and relatively low cost. The upcycled container architecture is being accepted since it is more eco-friendly than using the traditional building materials with intensive carbon footprint. Moreover, owing to the unquestionable urgency of climate change, existing climate-adaptive design strategies may no longer respond effectively as they are supposed to work in the previous passive design. Therefore, this paper explores an adaptive upcycled strategy of shipping containers as a carbon-smart modular living solution to a single family house under three design scenarios related to cold, temperate and hot-humid climatic zones, respectively. By assessing the projected future climate data with the ASHRAE Standard 55 and Current Handbook of Fundamentals Comfort Model, it was found that Rome would gradually face more failures in conventional climate adaptive design measures in the coming 60 years. The appropriate utilization of internal heat gains seems to be the most promising measure in Rome, followed by the measure of windows sun shading and passive solar direct gain by using low mass. Weather analysis shows different results in Berlin and Stockholm, where special attention should be paid to the occasional overheating risk. As a result, the holistic climate-adaptive container building design measures are finally summarized from aspects of design features, production / process and challenges in implementation.

Solar integrated building envelopes represent a significant energy harvesting potential in an era of decentralized building energy systems. This paper aims to simulate an energy system that consists of a transpired air solar collector component for a multifamily building cluster in Sweden. The energy system consists of an unglazed transpired solar collector in conjunction with air ventilation unit and exhaust air heat pump. The hot air from the solar collectors is used to increase the brine temperature at heat pump evaporator inlet to improve its coefficient of performance. The exhaust air heat pump is used to meet space heating and hot water demand for the buildings. The energy system is modelled using TRNSYS simulation program. The associated controls of the energy systems are optimized to increase the seasonal performance factor of the complete system, while maintaining the optimal performance of various subsystems. The quantification of the energetic benefits obtained from the proposed energy system is also presented using various key performance indicators. Furthermore, sensitivity analysis of different collector areas and operating variables such as airflow rate of the collector is conducted. The results show that the seasonal performance of the simulated energy system is 1.43 and the annual collector utilization factor is 0.18. Furthermore, the variation of the collector airflow rate has a positive impact on system performance, with an increase of 2 % in the annual heat pump coefficient of performance.