The fifth Assessment Report (AR5) published by the Intergovernmental Panel on Climate Change (IPCC) in 2013 stated that there is clear evidence that current global warming is caused by human activities. There is convincing evidence for the release of greenhouse gases (GHGs) such as carbon dioxide (CO2) from burning fossil fuels to produce energy (IPCC 2013).
It also stressed the need to reduce energy consumption and increase the energy efficiency of various systems (such as fuel consumption in cars or energy consumption in buildings). Energy is one of the main drivers of the global economy and energy consumption can be expected to increase in the future with the growth of the world's human population
Since 2010, more than 50% of the world's population lives in urban areas and this figure is expected to increase to 75% by 2050 (UN-Habitat 2009). Urban development and urban expansion, by modifying land use (from natural to artificial), modify the local energy budget and wind patterns: this causes a phenomenon called Urban Heat Island (UHI) ( TR Oke, 1982). Industrialization of urban areas has also contributed to air, noise and water pollution at these sites. Regulations have since been introduced to protect the health and well-being of urban citizens, as well as the existing fauna and flora.
Much of the world's energy demand has been linked to buildings which, as a result, are a major source of air pollution. About half of the primary energy consumption in Switzerland occurs in buildings. Of this energy, about 30% is consumed by heating space, cooling and heating water; 14% by the use of electricity and 6% by construction and maintenance (SFOE 2011). In addition, the building sector represents more than half of the CO2 emissions in Switzerland, which shows that it is among the largest contributors to carbon emissions. This also means that the building sector offers a real opportunity for a great improvement in energy efficiency and CO2 reduction.
The use of energy in urban areas also modifies the local thermal balance and can therefore lead to increased energy consumption in buildings. Architectural, design and construction techniques (insulation of walls or roofs, double or triple windows) are now used to build buildings that are more efficient and less energy intensive. When designing the model, modeling tools are often used to provide estimates of their energy consumption.
It is now well known that the urban climate depends on a series of processes that take place at different spatial scales (global to local) and temporal (Oke, 1982); The construction of energy demand and urban climate are also closely interrelated and interdependent (Ashie, Thanh Ca and Asaeda, 1999, Salamanca et al, 2011, Mauree 2014, Mauree et al., 2015). It is therefore essential to have access to tools that can accurately assess the interactions between buildings, their energy consumption and the local climate. Several models have been developed in recent years to better represent the different phenomena influencing the use of energy and the urban climate. However, most of these models work better at different scales (regional, urban, construction).
The complexity of the urban micro-climate can not be represented with simple physical formulas. Process parameters must be developed and integrated into models to simulate the processes that take place in an urban configuration and at different scales. The appropriate formulation of the parameters must be undertaken in two stages: the first measurements must be used to understand the physical processes (mechanical turbulence generation, buoyancy and thermal stratification, eddy size, etc.) in urban areas and the second generalization formulation These processes can then be developed.
Validation and replication using other monitoring studies are essential to improve turbulence, heat flux exchange, energy construction, thermal layering of the lower boundary layer and modeling of Atmospheric pollutants. It is expected that this monitoring will improve the representation of urban areas in meteorological models and improve the meteorological variables used as inputs in the construction of energy models.
For the reasons mentioned above, we have installed a 27m mast with instruments at a regular interval (4m) along the vertical axis to obtain a high-resolution profile of meteorological parameters. The mast has been installed on the EPFL campus, in Lausanne, Switzerland, next to the LESO experimental building.
The geographical location of the future monitoring tower makes it a very good candidate for the measurement of meteorological variables. The EPFL campus can be seen as a complex and dense urban setup (typical of a number of European cities) and the courtyard next to the LESO building as a canyon covered partially by grass and asphalt. Besides the location of the campus itself, is very interesting because of the thermal inertia of the lake as well as the close proximity to the mountains.
Energy Demand Analysis for Building Envelope Optimization for Hot Climate: A Case Study at AN Najah National University. PLEA 2016 - 36th International Conference on Passive and Low Energy Architecture, Los Angeles, USA, 2016.Detailed Record