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Climate change, heat waves and weather extremes unveil the need to counteract excess heat and its dramatic consequences on energy, economy, outdoor liveability and, above all, health. In the urban context, further concern arises from the concerted action of cities’ materials, fabric, layout, density and activities, which are responsible of heat and pollutants entrapment, of wind force breaking and sweltering microclimates. Ready-to-use, high-impact, smart, cost and energy-effective countermeasures are the only ones having chances to be widely implemented in the short haul. Against this backdrop, this work presents the results obtained from an experimental campaign conducted on a single mitigation technology, meant to reach high local temperature reductions and empowered with climate-adaptive features to be applicable close to any vulnerable target (e.g. schools, hospitals, hospices …): a web of smartly controlled mist sprayers. A prototype was designed and its impacts on the local microclimate were thoroughly characterized. Notably, the nozzle density was investigated to delineate the tradeoffs between evaporative cooling global magnitude and spatial dilution: in fact, by rarefying water emission, a larger air volume can partake to the cooling as it gets harder to reach saturation; conversely the point spatial temperature drop might weaken and become negligible, jeopardizing the whole mitigation strategy. This paper discloses such a controversial point and provides guidelines for the correct design of mist cooling systems for Urban Heat Island counteraction.

The next level of energy performance of new buildings within the European Union will be the Nearly Zero-Energy Building (NZEB). A lot of work has been spent on pilot and demonstration buildings on this and even higher energy performance levels throughout many EU countries. However, most of the high performance buildings realised so far result in additional investment costs when compared to the current national minimum energy performance requirements. The considerably higher investment costs are one of the main barriers to the early application of the NZEB-level in Europe. The EU Horizon 2020 project CoNZEBs works on technical solution sets that result in lower investment costs for NZEBs, bringing the costs close to those of conventional new buildings. The project focus is on multi-family houses. In each of the four participant countries Germany, Denmark, Italy and Slovenia a team of researchers is analysing which sets of market-ready technologies at the building envelope, the services systems for heating, domestic hot water, ventilation and cooling (where required) in combination with renewable energy systems can fulfil the NZEB requirements at lower costs than those incurred by the national mainstream NZEB application. Additional efforts are being spent on the life-cycle costs and the life-cycle analysis of the solution sets, as well as on the impact of future developments of primary energy factors, energy costs and technology efficiencies. Since details of the CoNZEBs work are presented in several additional papers, this document gives an overview of the different tasks and results that are available so far. The next level of energy performance of new buildings within the European Union will be the Nearly Zero-Energy Building (NZEB). A lot of work has been spent on pilot and demonstration buildings on this and even higher energy performance levels throughout many EU countries. However, most of the high performance buildings realised so far result in additional investment costs when compared to the current national minimum energy performance requirements. The considerably higher investment costs are one of the main barriers to the early application of the NZEB-level in Europe. The EU Horizon 2020 project CoNZEBs works on technical solution sets that result in lower investment costs for NZEBs, bringing the costs close to those of conventional new buildings. The project focus is on multi-family houses. In each of the four participant countries Germany, Denmark, Italy and Slovenia a team of researchers is analysing which sets of market-ready technologies at the building envelope, the services systems for heating, domestic hot water, ventilation and cooling (where required) in combination with renewable energy systems can fulfil the NZEB requirements at lower costs than those incurred by the national mainstream NZEB application. Additional efforts are being spent on the life-cycle costs and the life-cycle analysis of the solution sets, as well as on the impact of future developments of primary energy factors, energy costs and technology efficiencies. Since details of the CoNZEBs work are presented in several additional papers, this document gives an overview of the different tasks and results that are available so far.

The paper presents the findings on end-users' experiences and expectations about living in multi-family Nearly Zero-Energy Buildings (NZEBs). The survey in four European countries (Slovenia, Italy, Denmark and Germany) was part of EU Horizon 2020 project CoNZEBs (2017-2019) and addressed end-users living or thinking about living in multi-family NZEBs. Targeted end-users were living (as tenants or owners) in either ordinary buildings or in high performance buildings such as NZEBs (mandatory after 2020 according to Directive 2010/31/EU). In the survey, the following topics were addressed: the level of end-user's understanding of the NZEB concept, the source and quality of information on NZEB from the end-users' perspective, the importance of various apartment features for the end-users, perception of NZEB characterizing technologies, and decision triggers for living in NZEB. Concerns, doubts and eventual fears about living in NZEBs were studied to enable a tailored information for future end-users, to increase the demand for NZEB and beyond NZEB buildings and to improve their acceptability. To facilitate the living in NZEBs a guide for end-users was developed, explaining the "Myths" about NZEBs as well as presenting testimonials of current NZEB users in four participating countries. The paper presents the findings on end-users' experiences and expectations about living in multi-family Nearly Zero-Energy Buildings (NZEBs). The survey in four European countries (Slovenia, Italy, Denmark and Germany) was part of EU Horizon 2020 project CoNZEBs (2017-2019) and addressed end-users living or thinking about living in multi-family NZEBs. Targeted end-users were living (as tenants or owners) in either ordinary buildings or in high performance buildings such as NZEBs (mandatory after 2020 according to Directive 2010/31/EU). In the survey, the following topics were addressed: the level of end-user's understanding of the NZEB concept, the source and quality of information on NZEB from the end-users' perspective, the importance of various apartment features for the end-users, perception of NZEB characterizing technologies, and decision triggers for living in NZEB. Concerns, doubts and eventual fears about living in NZEBs were studied to enable a tailored information for future end-users, to increase the demand for NZEB and beyond NZEB buildings and to improve their acceptability. To facilitate the living in NZEBs a guide for end-users was developed, explaining the "Myths" about NZEBs as well as presenting testimonials of current NZEB users in four participating countries.