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Income, housing unit size, number of appliances owned and other components of socio-economic status (SES), are variables generally considered to influence residential energy use. Using structural equation modeling of SES indicators from the U.S. residential energy consumption survey (RECS), we provide evidence that SES, usually modeled as a latent construct with effect indicators, is better conceptualized as including at least some causal indicators. We studied the mediating effect of housing unit size and number of owned appliances on the relationship between SES, household size and residential energy consumption (REC). We found that household size was positively associated with REC, as a direct effect. SES had a strong impact on REC, while being mediated by housing unit size and number of appliances owned. In conclusion, research must take the latent nature of SES into account to uncover its total influence on REC. [ABSTRACT FROM AUTHOR]

Abstract: Cool roof technology is an energy efficient, financially viable and sustainable solution for mitigating heat islands and reducing building energy consumption for cooling. An EU supported project called Cool Roofs has achieved to promote this technology in the EU by the implementation of an Action Plan. The work is developed in four axes, technical, market, policy and end-users. The Action Plan is steered by the development of the European Cool Roof Council that brings together all related stakeholders. The main results of the project include the creation of the European Cool Roof Council (ECRC), five cool roof pilot studies, a database of cool roofing materials, a handbook and a toolkit to assist the better understanding of the technical aspects of the technology, a market promotion plan, a proposal for a successful strategy to overcome possible policy barriers and engage with key stakeholders who could support and accelerate the creation of an EU policy and regulatory friendly environment to cool roofs, the organization of workshops and seminars and other actions of dissemination. This paper presents the main achievements at EU level regarding the establishment of cool roofs as heat island mitigation strategy and a measure for reducing cooling loads. [Copyright &y& Elsevier]

Abstract: This research focuses on projecting the energy demand of the building sector in Greece by calculating energy consumption, using output data from regional climate models up to 2100. More specifically, Greece was subdivided into 13 climatic zones after assessing climate model data taking into account climate change estimates for the period 2010–2100. These zones allow a detailed estimation of the effects of climate change in specific regions of the country, thus creating a database which is used to model the energy demand of the building sector in each zone. Through the use of building data from Eurostat and the European Centre for Environment, a set of three building typologies was created in relation to the building envelope, which corresponds to 85% of the building stock in Greece. These typologies were later appended to each of the 13 climatic zones and a simulation for their energy demand was calculated using climatic data from 3 distinct climatic scenarios. Results show that the energy demand for heating the building sector in Greece could decrease by about 50%, while the respective energy demand for cooling could increase by as much as 248% until 2100. These effects are more evident in the Southern part of the country. [Copyright &y& Elsevier]

Abstract: This paper investigates the indoor thermal conditions in fifty low income non air conditioned houses in Athens, Greece, during the extremely hot summer of 2007. Hourly indoor temperature data have been analysed during three extended heat waves. Indoor temperatures as high as 40°C were recorded and the average indoor minimum temperature was always above 28°C. Mean indoor temperatures during the hot season were up to 4.2K above the normal climatic period, while the daily increase rate varied from 0.2K/day during the first up to 0.8K/day for the peak days of the heat wave. The exposure of inhabitants to high temperatures is very important because for almost 85% of the hot period, indoor temperature exceeded 30°C. Periods of about 216 continuous hours above 30°C, and six days above 33°C were recorded in many buildings. The dynamics and the evolution of indoor temperatures as a function of the outdoor climatic characteristics and the thermal capacitance of the buildings are analysed. Possible techniques to improve the indoor environmental quality in low income housing during extremely hot periods are discussed. [Copyright &y& Elsevier]

Abstract: Climatic change and heat island effect in combination with the non-proper design of buildings have increased substantially the cooling load of buildings. Night ventilation appears to be one of the more promising passive cooling techniques. Many important theoretical and experimental studies have been performed however the existing information is presented in a segmented way. The present paper analyses energy data from two hundred fourteen air conditioned residential buildings using night ventilation techniques. The specific absolute energy contribution of night ventilation has been calculated. The relation of the cooling demand of the buildings with the specific contribution of night ventilation has been investigated. It is found that the higher the cooling demand of the building, the higher the potential contribution of night ventilation under specific boundary conditions. The role of air flow rate is investigated as well. It is found that the global utilisability of the energy stored during the night increases as a function of the air flow rate and the tilt of the regression line between the energy contribution and the air flow rate increases significantly with the air flow rate applied, although the energy contribution per unit of air flow is decreasing. The whole analysis contributes towards a better understanding and evaluation of the expected energy contribution of night cooling techniques. [Copyright &y& Elsevier]

The method presented in this paper is a practical procedure for the derivation of a street canyon’s albedo, by taking into account the angle-dependent optical properties of a typical coated (SnO2) glazing. The development of the method is based on the flux transfer theory and can be easily implemented in a computer code permitting exploitation of a series of possibilities, such as street canyon geometry and window to wall ratios (WWRs). [Copyright &y& Elsevier]

Urban overheating affects the energy, health, power, survivability and environmental quality of cities. We calculated the magnitude of overheating in Sydney, Australia, at close to 9 °C, which causes a cooling penalty of up to 16% and an increase in the indoor overheating levels of up to 56%. We developed and evaluated eight heat mitigation scenarios based on the use of reflective surfaces, additional greenery, an increase in the evapotranspiration rate and several combinations of these factors. We estimated that mitigation can decrease the peak ambient temperature by up to 2.9 °C, reduce the maximum annual cooling consumption by up to 1.5 TWh, decrease the CO2 emissions by as much as 1.21 MT CO 2 , reduce indoor overheating by up to 80%, decrease the heat-related morbidity by 1.07–1.49, and decrease the heat-related mortality anomaly by as much as 1.39 per 100,000 citizens. We estimated the associated water penalty range to be between 80 and 100 Gl/year or between 13 and 16.7% of the water consumption in Sydney. [ABSTRACT FROM AUTHOR]

• Urban Overheating affects energy generation and demand, pollution, health and vulnerability. • It increases the energy demand for cooling and decreases the efficiency of power plants. • Rises the concentration of ground level ozone. • Increase indoor temperature in low income housing. • Increases heat related mortality and morbidity. Urban overheating is documented for more than 400 major cities in the world. Numerous experimental data show that the magnitude of the average temperature increase may exceed 4-5 C, while at the peak may exceed 10 C. Increased ambient temperatures cause a serious impact on the cooling energy consumption, peak electricity demand, heat related mortality and morbidity, urban environmental quality, local vulnerability and comfort. Synergies between urban heat island and heat waves increase further the amplitude of urban overheating The present paper reviews and reports the recent progress and knowledge on the specific impact of current and projected urban overheating in energy, peak electricity demand, air quality, mortality and morbidity and urban vulnerability. In parallel, it discusses new findings related to the characteristics and the magnitude of urban overheating, and reports and analyse the recent knowledge on the synergies between urban heat island and heat waves. [ABSTRACT FROM AUTHOR]