Energy Performance of Greenhouse for Energy Saving in Buildings

Abstract Nowadays it is necessary to reduce the energy consumptions of the built environment. This problem has led, in the last years, to a series of regulations to promote high performance systems. These can create a new way of building that is aware of the energetic consumptions. Besides the systems to use the solar radiation to produce energy (as active solar systems i.e. solar thermal collectors and photovoltaic modules) there are the passive solar systems such as the greenhouse. The greenhouse systems have a great potential to improve quality of living and energy performance of the buildings. However, it is now important to adopt a valid evaluation method to assess the project efficiency. There are already spreadsheets (for example SERRA 5000, based on Method 5000 and SERRA 832 , based on UNI EN 832/2001) which can evaluate energy performance and verify the effectiveness. The purpose of this research concerns the update of the existing spreadsheets for the winter (UNI EN ISO 13790/2008) and the definition of added spreadsheet for the summer period. In order to test this evaluation method, a case study has been evaluated and discuss

Energy Saving Through the Sun: Analysis of Visual Comfort and Energy Consumption in Office Space☆

Abstract Energy demands for heating, cooling and lighting can be dramatically prejudiced by the facade configuration, solar exposition and typology of openings trying to maximize use of natural light. Office buildings are often field of experimentation of materials and innovative components, by the way a consolidated design market promotes facade layouts strongly transparent introducing a primary need to shading and protection of the users privacy. Building Automation Systems (BAS) can reduce users' intervention on indoor condition control; on the other hand users want to be capable to fix conditions in their working space avoiding problems of visual discomfort, specifically disturbing and intolerable levels of glare. Systems to evaluate visual comfort parameters to improve consciousness in use of daylighting are fundamental in design to realize a facade which permits real energy saving during operation time. The present study aims to analyze a single office space with three differe nt configuration of the openings located in different orientation and position (south exposed window, north exposed window and skylight). The three cases study are evaluated on optimization of natural lighting, visual comfort, electricity consumption and h eating and cooling demand and consumption. To perform these kind of calculation with the correct level of detail is crucial to make use of a appropriate tools which can estimate the value of the different parameters to assess energy and visual quality of the indoor space. It is not possible to use just one tool to collect all the information required to optimize a building in order to obtain a NZEB level of consumption. The high standards required by the new regulations need a full -range analysis and a specific knowledge of all the parameters involved. In this study are used six software for the simulation of the all needed parameters (Ecotect, Radiance, Evalglare, Daysim, Dialux, Open Studio)

CFD Comfort Analysis of a Sustainable Solution for Church Heating

Historic building heating and, in particular, church heating represents a challenging task because many objectives have to be reached simultaneously, such as occupants thermal comfort and optimal internal climate suitable for the preservation of fragile building components and artworks. Moreover, current requirements for sustainability impose to make efforts, where possible, to minimize the amount of energy needed and the consequent environmental impact. Innovative solutions are currently under research and development and are mainly based on electric radiant surfaces. The present work represents actually a detailed performance analysis of a novel hydronic high-efficiency pew-based heating system coupled with a ground-source heat pump. The system was specifically developed for the above-described application field, with particular reference to the Basilica di Collemaggio (L'Aquila, Italy), a church of worldwide relevance currently under restoration. In detail, within the work a three-dimensional CFD analysis of the heating solution was carried out considering as application field a virtual test room containing two benches with three virtual sitting manikins. Heat exchanges between the human body surfaces, the room environment and the heated benches were simulated in order to assess the whole performance. The results show that the air temperature in the room is not significantly influenced by the heating system, but the heat is directly radiated to people, ensuring comfortable conditions and contributing to artworks preservation

Variability in genes regulating vitamin D metabolism is associated with vitamin D levels in type 2 diabetes

Mortality rate is increased in type 2 diabetes (T2D). Low vitamin D levels are associated with increased mortality risk in T2D. In the general population, genetic variants affecting vitamin D metabolism (DHCR7 rs12785878, CYP2R1 rs10741657, GC rs4588) have been associated with serum vitamin D. We studied the association of these variants with serum vitamin D in 2163 patients with T2D from the "Sapienza University Mortality and Morbidity Event Rate (SUMMER) study in diabetes". Measurements of serum vitamin D were centralised. Genotypes were obtained by Eco™ Real-Time PCR. Data were adjusted for gender, age, BMI, HbA1c, T2D therapy and sampling season. DHCR7 rs12785878 (p = 1 x 10-4) and GC rs4588 (p = 1 x 10-6) but not CYP2R1 rs10741657 (p = 0.31) were significantly associated with vitamin D levels. One unit of a weighted genotype risk score (GRS) was strongly associated with vitamin D levels (p = 1.1 x 10-11) and insufficiency (<30 ng/ml) (OR, 95%CI = 1.28, 1.16-1.41, p = 1.1 x 10-7). In conclusion, DHCR7 rs12785878 and GC rs4588, but not CYP2R1 rs10741657, are significantly associated with vitamin D levels. When the 3 variants were considered together as GRS, a strong association with vitamin D levels and vitamin D insufficiency was observed, thus providing robust evidence that genes involved in vitamin D metabolism modulate serum vitamin D in T2D

Serum Albumin Is Inversely Associated With Portal Vein Thrombosis in Cirrhosis

We analyzed whether serum albumin is independently associated with portal vein thrombosis (PVT) in liver cirrhosis (LC) and if a biologic plausibility exists. This study was divided into three parts. In part 1 (retrospective analysis), 753 consecutive patients with LC with ultrasound-detected PVT were retrospectively analyzed. In part 2, 112 patients with LC and 56 matched controls were entered in the cross-sectional study. In part 3, 5 patients with cirrhosis were entered in the in vivo study and 4 healthy subjects (HSs) were entered in the in vitro study to explore if albumin may affect platelet activation by modulating oxidative stress. In the 753 patients with LC, the prevalence of PVT was 16.7%; logistic analysis showed that only age (odds ratio [OR], 1.024; P = 0.012) and serum albumin (OR, -0.422; P = 0.0001) significantly predicted patients with PVT. Analyzing the 112 patients with LC and controls, soluble clusters of differentiation (CD)40-ligand (P = 0.0238), soluble Nox2-derived peptide (sNox2-dp; P < 0.0001), and urinary excretion of isoprostanes (P = 0.0078) were higher in patients with LC. In LC, albumin was correlated with sCD4OL (Spearman's rank correlation coefficient [r(s)], -0.33; P < 0.001), sNox2-dp (r(s), -0.57; P < 0.0001), and urinary excretion of isoprostanes (r(s), -0.48; P < 0.0001) levels. The in vivo study showed a progressive decrease in platelet aggregation, sNox2-dp, and urinary 8-iso prostaglandin F2 alpha-III formation 2 hours and 3 days after albumin infusion. Finally, platelet aggregation, sNox2-dp, and isoprostane formation significantly decreased in platelets from HSs incubated with scalar concentrations of albumin. Conclusion: Low serum albumin in LC is associated with PVT, suggesting that albumin could be a modulator of the hemostatic system through interference with mechanisms regulating platelet activation

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

Solare termico per la produzione di acqua calda sanitaria: Analisi prestazionale ed economica

La tecnologia del solare termico, come molte altre tecnologie oggi presenti sul mercato, consente di ridurre i consumi energetici da fonte fossile. Questa tecnologia ha una forte diffusione in ambito residenziale per la produzione di acqua calda sanitaria (ACS). Per questo è possibile trovare oggi sul mercato offerte in forma di “kit” per gli impianti solari termici pensati per un numero di utenti definito e contenenti tutti i componenti necessari all’installazione. Per questo lavoro sono stati selezionati 6 kit, attualmente presenti sul mercato, per valutarne le prestazioni e verificarne la capacità nel soddisfare le utenze consigliate. L’analisi è stata condotta su un’utenza tipo (4 persone) collocata in 3 differenti contesti climatici italiani. La località di riferimento è Milano, poi, per considerare le diverse condizioni climatiche della penisola, sono state prese in considerazione anche le località di Roma e Trapani. L’analisi effettuata è di tipo tecnico, economico ed ambientale. L’analisi tecnica mette a confronto 3 kit a collettori solari piani vetrati e altri 3 kit a collettori evacuati. L’analisi economico valuta il tempo di ritorno semplice (VAN) delle diverse tipologie considerate mentre la valutazione ambientale evidenzia la riduzione di emissioni di CO2 evitate con tale tecnologia. Le valutazioni hanno evidenziato come a volte l’acquisto di questi kit preconfezionati e facilmente acquistabili sul mercato, non sono sempre mirati all’efficienza ed ottimizzazione complessiva di questa tecnologia che sfrutta una fonte rinnovabile solare. In particolare un kit adatto ad una specifica località non risulta tale in un’altra ove la disponibilità di radiazione solare è ben differente

District heating in Lombardy Region (Italy): Effects of supporting mechanisms

Nowadays energy and environmental issues represent the main emergencies for all the governments,globally and locally. The importance of operating on the three levels of the energy system (by reducingenergy demand; by optimizing generation and management and by integrating local renewable energysources) has been strongly recognized. To that end urban neighborhoods could represent an optimal scalefor the implementation of innovative energy strategies, despite barriers at the economic, regulatory andadministrative level are still present.In recent years, as a result of an important agreement with the Italian Ministry of Environment, Lombardy Region has supported numerous measures for energy efficiency and renewable energy sourcesintegration among its territory, including district heating plants. All the interventions were analyzed inthe framework of a wider monitoring campaign aimed to evaluate effects, effectiveness, pros and cons ofthe several calls and programs. The financed district heating plants represent the case of studies describedin the present paper.The most important characteristics, conditions and technical features of these interventions were analyzed. Globally we deal with 21 interventions distributed in the territory of Lombardy Region and fueledby fossil fuels, waste or biomass. The results obtained were described in terms of environmental, energyand economic performances, taking into account the public spending and the global investment costs.The main aim of the analysis is to comment the effectiveness of the adopted local energy policies andalso to orient future policies toward the improvement of the energy and environmental performances ofcommunities and territories

Solar Photovoltaic and Thermal Systems for Electricity Generation, Space Heating and Domestic Hot Water in a Residential Building

In this paper a techno-economical analysis has been carried out for the solar energy technologies (PV and thermal) and GSHP system employed for energy supply in a residential building for different end uses e.g. heating, hot water and electricity. The building is a three-story located in Milan, Italy. The building was designed based on current regulations on energy efficiency in buildings. The HVAC system is designed for minimising energy consumption by the appropriate choice of the heating and cooling systems. The space heating energy is supplied by a GSHP system with vertical ground heat exchangers. The domestic hot water is produced by a solar thermal system. A major part of electricity required for lighting, domestic appliances and the functioning of GSHP system is generated through a PV system. Both the solar thermal and PV systems are installed on the building roof

Beyond the EPBD: The low energy residential settlement Borgo Solare

The European Directive on Energy Performance of Buildings (EPBD) imposes the adoption of measures for improving the energy efficiency in buildings. These measures should take into account the local weather conditions as well as internal thermal environment and cost-effectiveness. In this respect, Italy is a very interesting benchmark. For Northern Italy, the climatic context is particularly difficult to deal with cold winters and hot summers. The legislations are changing very rapidly, but has not fully adapted to the local context. The considered methodology still involves winter heating while summer cooling is addressed in incomplete and inadequate ways. The energy issue is addressed only partially as final energy consumption, but with little attention to LCA. Moreover, the belief that the buildings with high energy savings are too expensive, and therefore not attractive from economic point of view. For these reasons, it is very important to develop case studies to demonstrate the effectiveness of sustainable energy in architecture, according to a holistic approach. This paper describes a detailed techno-economic analysis for Borgo Solare project, an extremely advanced and innovative residential settlement designed on sustainable architecture concepts. One of the most innovative aspects of the project is that it is not just an experimental operation but Borgo Solare is a real urban district, which will be built without public funds and should be inhabited by common people. Excellent energy performance, therefore, must be accompanied by affordable market prices. The energy and economical analysis is presented taking into account also the embodied energy of the building. The results on the performance of a sample building (case study) of this settlement are reported, according to different construction standards: prior to EPBD, present from the EPBD and more efficient developed specifically for the project. It has been shown that using the better design practices and technologies the higher initial embodied energy in a low energy building could quickly paid back during its life span. The economic analysis, in the same way, evidences that higher initial investment in case of energy efficient building could become economically convenient during the life span of the building. This kind of analysis is essential to determine the actual sustainability of a building.Borgo Solare project Sustainable architecture Operating energy Embodied energy Energy performance Economical evaluations