Know more

Context:

On the one hand, the overall environmental context is marked by a visible climate change leading to a collective awareness. Face to these evidences, international governments engaged themselves to reduce our environmental impact, in particular by limiting global warming to 1.5°C by 2100. The levers to reach this objective mainly consist in limiting our greenhouse gas emissions especially by reducing our energy needs, these lasts being responsible for a large amount of our emissions. The assessment of building energy efficiency is an important lever to reach this objective. Indeed, buildings account for 32% of the energy used and represent 19% of the greenhouse gas emissions in link with energy production.

On the other hand, at the local scale, cities encounter modifications of their microclimate due to surface artificialization. It leads especially to the urban heat island effect that reflects the fact that cities are warmer than their surroundings. For instance, the mean urban heat island intensity in Paris is +3°C, but can reach +10°C in nocturnal summer conditions. It induces many consequences, especially during heat waves, on citizen comfort and health. Among the numerous causes of urban heat island, the anthropogenic heat release is responsible for one third of this phenomenon. This source of heat originates in particular from building, especially from the use of cooling systems in summer releasing heat outdoor, and heat losses in winter.

Therefore, the assessment of the building thermal insulation allows to act on global climate by assessing the energetic performance, but also on local microclimate by limiting the anthropogenic heat release. To reach this goal, it is of course possible to use traditional technics (double/triple glazing, performant insulating materials), but the green roofs can also contribute to building insulation. However, their impact and its variability remain only few studied and quantified.

Internship objective and schedule:

The internship will aim to quantify the impact of green roofs on building thermal insulation. To do that, it will follow the steps hereafter:

-          Bibliographic synthesis of the existing studies on this topic,

-          Analysis of experimental data obtained in in situ conditions to determine the thermal characteristics (U-value, or thermal conductivity, volumic mass and specific heat capacity of the different layers – substrate and vegetation) of the green roofs, and determination of the factors responsible for their variations (soil water content, kind of substrate, vegetation type, etc…),

-          From an existing model calibrated for a real case study (HLM building in Montreuil), determination of the impact of green roofs on building energy consumption by integration of the thermal characteristics previously determined, and comparison with other cases (without insulation, with traditional insulation, ect…).

Required skills:

-          Skills in data analysis

-          Interest for experimental and modelling approaches

-          Interest for environmental issues

-          Autonomy and rigor

Work environment:

The student will be located during the first half of the internship at Palaiseau at the UMR INRAE/AgroParisTech ECOSYS, and during the second half of the internship at the Centre Efficacité Energétique des Systèmes de Mines Paris. This internship will also join the works of the Lab Recherche-Environnement Vinci-ParisTech where AgroParisTech and Mines Paris are partners.

The management will be performed by:

-          Patrick Stella (patrick.stella@agroparistech.fr)

-          Erwan Personne (erwan.personne@agroparistech.fr)

-          Bruno Peuportier (bruno.peuportier@mines-paristech.fr)

Employment contract:

The internship will give a gratification of 508.20 euros per month+ repayment of 50% of the transport pass.

Application:

Send a detailed CV, a motivation letter, and the contact information of 1 referent to:

-          Patrick Stella (patrick.stella@agroparistech.fr)

-          Erwan Personne (erwan.personne@agroparistech.fr)

-          Bruno Peuportier (bruno.peuportier@mines-paristech.fr)