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A mathematical model based on one-dimensional energy and mass balance across the solar chimney has been developed. The air flow characteristics such as exit velocity and temperature are evaluated with respect to the collector inclination angle, hourly solar radiation, ambient temperature, and wind speed. The model is validated by comparing the performance parameters obtained, with the experimental results and also with the experimental data of different geometrical range and environmental conditions from the literature. An average deviation of 8% for exit air velocity and 1.35% for exit air temperature is obtained for the solar chimney with absorber inclination angle 30°, collector area 0.41 m 2 , and chimney height 0.24 m. The experimental daily average and maximum exit air velocity during the month of April are 0.5 and 0.88 m/ s, respectively. The predicted optimum operating conditions are 75°inclination angle, 0.63 m 2 absorber area, and 0.48-m chimney height. The maximum average exit air velocity and temperature numerically obtained are 0.64 m/s and 331 K, respectively, when operating with optimum conditions. It is observed that the exit air velocity increases 33% by increasing the absorber area from 0.5 to 3 m 2 for a solar chimney with 0.5 m height. An increase in exit air velocity of 52% was obtained by increasing the chimney height from 0.5 to 3 m for a solar chimney with 0.64 m 2 absorber area. A reduction in exit air velocity of 4% was observed for the increment in wind flow over the glass cover from 1.5 to 3 m/s. These results confirm that the solar chimney could be designed based on the predicted monthly performance by the present model.

Global warming and climate change are the foremost environmental challenges facing the world today. It is our responsibility to minimize the consumption of energy and hence reduce the emissions of greenhouse gases. Companies choose ‘Carbon Footprint’ as a tool to calculate the greenhouse gas emission to show the impact of their activities on the environment. In this working paper, we assess the carbon foot print of an educational institution and suggest suitable measures for reducing it. Greenhouse gas emitting protocol for an academic institution in terms of tones of equivalent CO2 per year is projected using three basic steps includes planning (assessment of data’s), calculation and estimation of CO2 emitted. The estimation of carbon foot print is calculated by accounting direct emission from sources owned/controlled by the educational institution and from indirect emission i.e. purchased electricity, electricity produced by diesel Generator (DG), transport, cooking (Liquefied Petroleum Gas) and other outsourced distribution. The CO2 absorbed by trees are also accounted. Some of the options are identified in order to reduce CO2 level. The information of corporate carbon footprint helps us identifying the Green House Gases (GHG) emission “hot spots” and identifies where the greatest capacity exists in order to reduce the GHG emissions. The main prioritization goes to transport and then followed by DG, cooking and then electricity. The per capita CO2 emission and the total CO2 emission for a typical educational institution are estimated.

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