MULTICRITERIA PRIORITIZATION OF POLICY INSTRUMENTS IN BUILDINGS ENERGY RETROFIT

Improvement of energy-efficiency in residential buildings is a crucial issue in Italy, where 55% of the building stock is older than 40 years and real estate assets are responsible for 33% of primary energy consumption. Consequently, the Italian residential sector offers considerable potential for reducing energy use and GHG emissions, particularly through energy-efficient renovations. Governments can introduce a wide range of policy instruments to encourage households in undertaking energy-efficient renovations: direct financial investments, regulatory instruments (e.g., performance and technology standards), economic and market-based instruments, support information and voluntary actions. Since 2006, the Italian Government has introduced fiscal incentive programs to enhance energy efficiency in residential buildings. During the period 1998-2016 the cost for the Italian Government to due to fiscal incentives (i.e. tax deductions) was extremely high compared to tax revenues. Thus incentives turned out to be excessively costly and not cost-effective. The design and implementation of incentive policies to buildings energy retrofit is a complex process involving a great number of decision variables and actors. Cost-effective incentive policies should prove capacity in stimulating investments, reducing social and environmental costs and promoting innovation. This complexity is exacerbated in the presence of stringent public budget constraints and lack of financial resources. In order to favor the implementation of cost-effective retrofit strategies, the policy maker must take into consideration along with buildings age and construction materials, social costs and benefits, EU and national targets, and environmental concerns. In this context, where multiple objectives need to be pursued, multiple criteria approaches provide a methodological framework to address the complexity of economic, physical, social, cultural and environmental factors which characterize incentive policies. In this paper we propose a multi-criteria decision model to support the policy maker in ranking sustainable incentive policies. In detail, we provide an AHP model for multiple-criteria prioritization of policy instruments to foster investments in energy retrofit of existing buildings

LA VALUTAZIONE DELLE MISURE DI RIQUALIFICAZIONE ENERGETICA NELL’EDILIZIA RESIDENZIALE PUBBLICA: UN APPROCCIO GERARCHICO

In this paper we provide a multiple criteria model, based on the Analytic Hierarchy Process (AHP), to rank alternative packages of energy retrofit measures (ERMs). Following the AHP methodology, a hierarchy was created and a group of experts ranked all the elements of the hierarchy at each level. The prioritization of ERMs was set as the goal at the top of the hierarchy, three families of criteria (i.e., economic, environmental and social) and a set of sub-criteria were identified, whereas at the lower level of the hierarchy alternative packages of implementable ERMs are positioned. We found that Economic criteria play a major role in the achievement of the goal, in addition the Life Cycle Cost (LCC) of the building emerged as the most important sub-criterion. Thermal insulation of the building envelope resulted as the most important alternative: it contributes to minimization of management and maintenance costs and ensures thermal comfort throughout the useful life of the building. Specifically, the cost-effectiveness of this ERM may significantly contribute to reduce fuel poverty

Energy efficiency in buildings: willingness to pay for buildings energy retrofit

The aim of this research was to provide innovative valuation approaches of building energy retrofit projects. We analysed the cost-effectiveness of building energy retrofit projects taking into account the trade-offs between costs and direct, indirect, tangible and intangible benefits of retrofit solutions. In detail, the research focused on the estimation of the monetary value of benefits and co-benefits related to BER which may boost investment in building energy retrofit projects. In the end, we provided interesting policy implications to support the Italian Governments in the design of optimal incentive policies.Lo scopo di questa ricerca è quello di fornire approcci innovativi di valutazione economica dei progetti di riqualificazione energetica degli edifici. Abbiamo analizzato il rapporto costo-efficacia dei progetti di riqualificazione energetica degli edifici tenendo conto dei trade-off tra costi e benefici diretti, indiretti, tangibili e intangibili delle soluzioni di retrofit. Nel dettaglio, la ricerca si è concentrata sulla stima del valore monetario dei benefici e dei co-benefici relativi al retrofit energetico degli edifici che potrebbero favorire gli investimenti. Alla fine, abbiamo anche fornito interessanti implicazioni di policy per supportare i governi italiani nella progettazione di politiche di incentivazione

Experimental and numerical study of the cyclic behavior of exterior RC beam-column joints made with recycled concrete

An experimental and numerical investigation about exterior reinforced beam-column joints made with recycled concrete, and subject to horizontal reversed cyclic loading, is shown in this paper. Three real scale RC joints were casted with electric arc furnace slag as recycled coarse aggregate, and then tested under quasi-static cyclic loading, to study the influence of this kind of \u201cgreen concrete\u201d on the global behavior of the specimens. Particularly, ultimate load, hysteresis response and dissipated energy were analyzed. The joints exhibited the same failure mode, which involved the shear failure of panel joint and yielding of beam steel longitudinal bars: this kind of failure is indeed the most influenced by concrete properties. Then a numerical investigation was carried out, consisting of three- dimensional nonlinear finite element (FE) models, which were validated with the experimental results. Lastly, a parametric study was carried out to understand the effects of column axial load, beam longitudinal reinforcement bar amount and column transverse reinforcement ratio. Results indicate that, in all the analyzed cases, the seismic performance of the joints made with EAF slag concrete at least comparable than with conventional material

Experimental and numerical investigation on the cyclic behavior of RC beam column joints with EAF slag concrete

An experimental and numerical study about exterior reinforced beam-column joints made with recycled concrete containing Electric Arc Furnace (EAF) slag aggregate, and subject to horizontal reversed cyclic loading, is shown in this paper. Three real scale joints were tested under quasi-static cyclic loading, to study the influence of EAF concrete use on the global behavior of the specimens, in terms of ultimate load, hysteresis response and dissipated energy. The joints exhibited the same failure mode, which involved the shear failure of panel joint and yielding of beam steel longitudinal bars. Then a numerical investigation was carried out, consisting of three-dimensional non-linear finite-element (FE) models, which were validated with the experimental results. Lastly, a parametric study was carried out to understand the effects of column axial load, beam longitudinal reinforcement bar amount and column transverse reinforcement ratio. Results indicate that, in all the analyzed cases, the seismic performance of the joints made with EAF slag concrete is better than with conventional material