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According to the recent EU Directives on building energy efficiency, the Italian government is paying particular attention to energy refurbishments of buildings by enacting energy measures and obtaining significant results. In particular, the Italian government is providing economic incentives to citizens or public administrations that improve the envelope of the energy performance of a building. However, according to strict national regulations concerning building heritage, most actions cannot be applied to historic buildings, even though they represent approximately 30.1% of all buildings. In this context, the energy retrofits for Italian buildings are not simple but necessary. Therefore, in this work, a public historic building was simulated, and some permitted retrofit actions were applied to analyse the effectiveness of national measures in four different climatic zones. The results showed that the same applied action that reduces the primary energy consumption in some zones will significantly increase consumption in other zones, even if the zones fall within the same case-law. Finally, the results highlight two main unsolved issues: the renewable energy source installation of a historic building and a strong distinction between measures and economic incentives around the Italian peninsula, which has very different climate conditions.

This study investigates energy efficiency in buildings. The accurate evaluation of energy consumption in existing buildings is a difficult task, particularly due to the Mediterranean climate, which is in the temperate zone. Among the various analytical models, the most effective measurement of the energy consumption of buildings is the dynamic type. In evaluating the energy consumption of buildings, the greatest contribution is provided by opaque components and particularly by the external walls of that building. In the model, which is reported in the EN ISO 13786, the thermal properties (the specific heat (J/kgK) and thermal conductivity (W/mK) of the layers of the wall were tested, and the technical standard reported that the physical properties (from which they derive the phase shift and decrement factor) transferred through the wall when a sinusoidal wave temperature variation was applied in a periodic steady state. We propose an inverse approach to measure the sinusoidal periodic steady state (temperature and thermal flux) on the two faces of the wall. With this approach, it is possible to obtain the thermal properties of the wall through an inverse analytical model. The model was applied in a real experiment on a full-size wall in a climatic chamber to verify the dynamic thermal and physical properties of the layers.

The demand on reducing energy consumption of buildings, recently became tighter and tighter, as well as the need of shortening the building materials’ supply chain. It is generating a growing attention to natural and local construction materials and opening new and interesting research scenarios. The use of novel materials makes necessary reaching a deeper and appropriate understanding of their thermal performances by means of an accurate thermal characterization. The present research has been addressed at testing and verifying the thermal performance of Sardinian local masonry materials (hollow clay blocks and adobe bricks) and three different natural insulations: cork, sheep-wool and reeds. By the use of a dedicated hot box apparatus, working on full-scale wall models, the thermal resistance of eight different samples has been measured and then compared with the theoretical values calculated according to current standards. The results show that the measured values are by far higher than the calculated ones and that the use of local natural materials, if not accompanied by a rigorous standardization of production and installation procedures, can lead to overestimate their thermal performances.

In this work the uncertainties related to the optimal planning/allocation of government subsidies for residential building stocks retrofits are considered and the uncertainty based planning problem is formulated and solved as a multi-objective, constrained problem. Different multi-objective algorithms are considered with the idea to determine the most effective and efficient approach that can be customized as planning tool to be used by the public administration personnel. The preliminary comparison between 2 multi-objective evolutionary algorithms and a deterministic one is presented and optimal/pareto results are analysed.

The strict energy saving standards are based on the declared values of the materials, i.e. U-value, thermal conductivity or thermal capacity. To this end, proper knowledge of the thermophysical properties of the wall components is needed, especially with regard to new lightweight technologies that are being used in building construction/refurbishment, under the dynamic conditions of the Mediterranean climate, where one of most important parameters of building materials is their heat capacity because of the influence of solar radiation energy. With this regard, the actual heat capacity value, obtained in laboratory tests, is typically quite different from the nominal one. So, this paper reviews several methods of calculating the heat capacities of materials and several worldwide applications, with the aim of providing an overview of the thermal behaviour of lightweight insulation materials and their implications for energy and indoor comfort. Finally, the authors propose a simple method able to evaluate the specific heat capacity of real scale building materials with a ~5% of uncertainty.

Traditional energy retrofit interventions focus on reducing energy requirements and costs, which can be achieved by acting on the envelope or on the plants, without taking into account that the conditions of indoor air quality and thermal, visual and acoustic comfort, provided for by current legislation, must be maintained. To the in place mea-surement campaigns of the energy parameters before and after the retrofit intervention, should be added those relating to the IEQ sectors. The results of the various measures in the field must be analyzed in synergy, using a rigo-rous or simplified approach, evaluating the sensitivity of energy costs to individual retrofit interventions, always on equal terms. This theme is addressed in all fields by the Operative Units 2 and 4. This paper presents an example case study that simply gives an idea of the problem.

Thermal conductivity is one of the most important parameters for construction and building materials. Indeed, extensive efforts have been put in by Europe in order to decrease energy consumption at various levels. However, with regards to historical buildings, the measures of thermal performance are not simple and they, in fact, pose a wide range of error. In this paper, an intermingled fractal model has been proposed, which is capable of reproducing the porous microstructure. Moreover, by converting this model into an electrical circuit, it is capable of predicting thermal conductivity. The results are in perfect agreement with experimental ones obtained by climatic chamber.

Thermal comfort and energy saving have become a priority for construction industry professionals. An important parameter of the comfort is the mean radiant temperature and its dependence on the building envelope. In the present research, a dynamic physical model has been studied in a climatic chamber, linked to the specific heat (C), density (r) and thermal conductivity (l). The heat capacity is usually quantifiable in small, homogeneous and uniform samples by the application of calorimetric methods. Consequently, the building energy consumption assessed through calorimetric methods, is often quite different from the energy consumption measured in situ. In this work an experimental model for the assessment of specific heat of real-size building components is proposed. Such a parameter was determined by measuring the heat flow through a building wall. The model has been validated by comparing the evaluated properties of known materials for different thermal gaps.

Olje- og gassinstallasjoner i sensitive områder med tøffe miljøforhold kan kreve forbedret risikovervåkning, vurdering og styring for å forhindre og begrense skaden forårsaket av utilsiktet hydrokarbonutslipp i sjøen. Dette problemet er en prioritet når installasjonen som undersøkes ligger i et område som er definert som følsomt. Foreliggende arbeid omhandler en reell referansefallstudie, en offshoreinstallasjon lokalisert i Barentshavet, som representerer et relevant eksempel på nyskapende anlegg som opererer offshore i den arktisfølsomme regionen. Hydrokarbonprosesslekkasjer er en viktig bidragsyter til offshore-risiko. Scenariene som kan utvikle seg fra prosessområdet til denne installasjonen, er valgt gjennom bruk av en lekkasjefrekvensmodell og modellering av sikkerhetsbarrierer. Prosesslekkasjen for offshore installasjon Frekvensvurderingsmodell estimerer prosesslekkasjefrekvensene for bruk i kvantitativ risikoanalyse av brann og eksplosjon ved installasjoner lokalisert på norsk kontinentalsokkel. Det er basert på antakelsen om at lekkasjefrekvensen er proporsjonal med antallet av hver type utstyr. Prestasjonene til sikkerhetsbarrierer har blitt brukt som QRA-parametere. Miljørisikoen blir evaluert gjennom en eksponeringsbasert analyse, basert på varighet, hastighet og mengde frigjøring samt oljedriftssimulering. Dette trinnet er utført takket være SINTEFs programvare OSCAR - Oil Spill Contingency and Response. Nivået på estimert risiko blir deretter sammenlignet med de strenge tolerabilitetskriteriene som installasjoner som ligger i sensitive områder blir utsatt for, gjennom en risikomatrise. Oil and gas installations in sensitive areas with harsh environmental conditions may require improved risk monitoring, assessment and management in order to prevent and limit the damage caused by accidental hydrocarbon spills in the sea. This issue is a priority when the installation under examination is located in an area defined as sensitive. The present work deals with a real reference case study, an offshore installation located in the Barents Sea, which represents a relevant example of innovative facility operating offshore in the Arctic sensitive region. Hydrocarbon process leaks are a major contributor to offshore risk. The scenarios that may develop from the Process area of this installation have been selected through the application of a leak frequency model and the modeling of the safety barriers. The Process Leak for Offshore installation Frequency Assessment Model estimates the topside process leak frequencies for use in Quantitative Risk Analysis of fire and explosion at installations located on the Norwegian Continental Shelf. It is based on the assumption that the leak frequency is proportional to the number of each type of equipment. The performances of the safety barriers have been used as QRA parameters. The environmental risk is evaluated through an exposure-based analysis, based on duration, rate and amount of the release as well as oil drift simulation. This step has been carried out thanks to the SINTEF’s software OSCAR – Oil Spill Contingency and Response. The level of estimated risk is then compared with the stringent tolerability criteria to which installations located in sensitive areas are subjected, through a risk matrix.

The goal of the research is to propose an optimization-based methodology for the evaluation of retrofit incentives, using as a benchmark the wide data collection reported by the ENEA Italian Agency since 2007. To determine the best mix of energy retrofit measures for different areas of Italy, two Linear Programming models are proposed. The first model maximizes energy savings and the second one minimizes retrofit costs. The results show a 17% reduction in the average cost for each MW h of saved energy. More importantly, the methodology can help decision-makers appreciate how energy efficiency incentives have been used so far and how effective they could be. Furthermore, the methodology can be used for setting future incentive distribution plans.

Italian energy policy has determined important keystones in building energy efficiency regulations and their application throughout the country. However, there is still much work to be done in order to make sustainable societies and territories, especially in historical contexts that have the greatest potentiality of energy saving. In detail, in the framework of conservation, restoration, refurbishment, and retrofit actions, the debate among scientists, administrators and skilled people is still open due to the many aspects yet to be considered and solved. In this paper, the state of the art of Italian residential building heritage has been reviewed, while energy retrofit issues and viable solutions have been investigated by collecting literature examples and experiences, focusing on common retrofit measures on historical buildings per thematic area. Finally, the advantages and disadvantages of each action have been discussed. Anyway, two main aspects have to be solved yet: the high Payback Times and the restriction about Renewable Energy Sources installation on this kind of buildings.

In this work the energy cost of a human operator during the harvesting of saffron flowers is discussed. The amounts of energy cost was achieved for a traditional harvesting hand-made activity compared to a harvesting phase with a facilitator machine. In the paper the facilitator machine prototype is described with its mechanical performances. Oxygen uptake (VO2) and carbon dioxide consumption (VCO2) were taken in five male healthy volunteers using a progressive exercise test on a cycle ergometer to calculate the respiratory ratio (VCO2/VO2) corresponding to the anaerobic threshold (AT) which, just it exceed 1, indicates the fatigue onset. VO2 was also assessed when volunteers simulated hand-made saffron harvesting or assisted by the facilitator device, to establish if the VO2 reached or not the AT value/fatigue onset in the one or in the other harvesting modalities.

The aim of the research is to investigate the role of the microclimatic conditions and their variations on the decay due to salt crystallisation, observed in a semi-confined archaeological site, in an urban area. A microclimatic monitoring was carried out in the site to detect temperature and relative humidity and their respective variations. Statistical methodology was conducted to examine the microclimatic data with seasonal, monthly and daily analyses. Different zones of the site were monitored and a microclimatic zoning was detected. The outside environment influences the most external zones of the site, while in the confined ones a high relative humidity was detected in all the seasons. The comparison between the hygrothermal conditions monitored in the site and those thermodynamic favourable to salt crystallization revealed a very harmful risk of salt damage for the archaeological structures.

The application of retrofit actions to existing building stocks can improve the energy performance of the residential sector. In this context, particular attention should be given to historical buildings, which represent a large part of the Italian building stock. To improve the energy performance of them, adequate retrofit actions must be applied. Many studies and regulations have focused on identifying the best refurbishment measures. However, the selection of these measures is difficult due to restrictive regulations, which are dictated by the Ministry of Cultural Heritage and Activities, high retrofit costs, and variable climate zones. Thus, energy renovations in Italian buildings are not simple, and it is very difficult to find generic solutions that can be applied to buildings across the entire territory. In this paper, the authors investigated the most common retrofit solutions used in Italy, focusing in particular on the energy performance of historical building envelopes. First, energy performance analyses were conducted for two typical base cases in four different Italian cities using TRNSYS software, and some common retrofit measures were analysed. In some cases, the results showed Primary Energy saving of 44.6% (sample A) and 56.7% (sample B). Furthermore, these were used to identify different energy and economic impacts associated with the same refurbishment measures in different climatic contexts, highlighting the non-existence of a generic solution suitable for all regions or countries.