Massimiliano Scarpa

Thermo-physical performances of living walls via field measurements and numerical analysis

In the urban area the air temperature has been growing at a faster rate (Urban Heat Island UHI) leading to greater use of air-conditioning and energy demand. One possible strategy to lower ambient temperature is to increase the amount of greenery in the city. In this context we have assisted recently in a rediscovering of buildings envelopes claddings by green walls, living walls and green roofs. Green walls may consist of green facades made up of traditional creepers and living walls are vertical claddings with plants, installed on the building facade. A very detailed field measurement campaign was performed on a living wall with the aim of evaluating its performance versus a traditional envelope. The field measurements were performed between June and September 2011. Hourly measurements of surface temperatures, heat fluxes, ambient and internal temperatures, ambient and internal relative humidity, air velocity in the living wall cavity and climatic variables have been collected for the bare and covered wall. Using a numerical model, validated via field measurements, a multiparametric analysis has been performed considering the effect on energy consumption and temperature behaviour for different orientations of the living wall in different locations.

Parametric study on the financial performance of battery-supported photovoltaic systems connected to smart grids in current and future market scenarios

This article presents the economic performance of battery-supported residential photovoltaic systems connected to smart grids in the presence of a market-driven electricity tariff. In particular, the article deals with the economic benefit resulting on varied photovoltaic system and battery sizes, through a parametric analysis. Such an analysis is strongly dependent on the costs of photovoltaic systems and battery packs, which are prone to decrease in the coming years, according to many authors. In this context, the article investigates current and forecast economic scenarios, in order to show the expectable improvement in the financial performance in systems installed in the next few years. For this purpose, the article includes a review of photovoltaic system and battery prices forecasts for the coming years. The financial analysis takes into account two different (and conservative) feed-in tariffs: in the first case, the hourly national price of electricity is used as a feed in tariff, in the second case no reimbursement is considered for exported electricity, thus considering the case of wide photovoltaic system penetration and a consequent photovoltaic electricity overproduction.

Towards Near Zero Energy Dwellings By HeatPump Implementation In HVAC Plants

The EPBD (Energy Performances of Buildings Directive) updated on 9 July 2010 imposes new rules for energy savings in buildings. By 31 December 2020 all new buildings must be nearly Zero Energy Buildings (nZEB) with reference to the consumption of fossil fuels. The roadmap that each nation is adopting for this purpose imposes a further significant increase in the share of the building energy requirement covered by renewable energy. Achieving this goal at acceptable costs for the communities represents a real challenge considering the current state of the art. The role of Eco-Architecture will be fundamental in this phase of introduction and spread of innovative techniques in the design of building-plant system. For this aim, the installation of heat pumps for building heating is able to contribute significantly in terms of better energy performance and exploitation of renewable energy. In fact, in the EPBD the energy from heat sources of heat pumps (air, ground, water) is considered renewable energy. An assessment about the possibilities and limits of the electric heat pump installation in dwellings is here reported for different case studies and climates in Europe.

Intelligent Buildings Connected To Future Smart Energy Grids

The spread of diffuse energy generation systems such as photovoltaics and combined heat and power generators will convert buildings from sole energy consumers into energy prosumers, i.e. energy producers and consumers. This will involve a much more dynamical interaction between buildings and the energy grid. As a consequence, electric distribution networks will be required to coordinate the energy draw/supply in order to optimize the use of renewable energy sources and preserve the reliability of the energy dispatch system, thus becoming smart grids. Smart grids will be able to act as coordinators of energy flows between diffuse energy producers and consumers, but buildings will be mainly managed in order to minimize their interaction with energy grids, thus minimizing the volatility of energy supply/draw, thus they will integrate energy management systems aimed at taking advantage of locally generated energy. In fact, buildings will be required to locally generate as much energy as possible, towards a Zero Energy Building perspective. For this purpose they will exploit technologies able to modulate energy demand and production by a suitable design of the building. So how will buildings, and consequently the related architecture, evolve in order to achieve these goals? In this paper the present status of the art as well as building configurations, procedures and energy management strategies able to ensure the best integration of typical residential and office buildings into smart grids are analysed.