7 Mathematical Modelling of Solar Updraft Tower
113
2. In case 2, convective as well as radiative losses through the collector roof were
calculated. Also, the absorptivity and reflectivity of the roof was determined.
Thus, the actual heat flux involved in power generation was calculated for June
and corresponding power output was estimated to be around 74 kW and the
collector efficiency turned out to be nearly 80%. Theoretically, when averaged
over the year, the power output could be around 60 kW, which is around 20%
more than the plant in Manzanares.
3. The peak power output for case 1 was found to be nearly 145 kW and for case
2, it was around 120 kW.
4. The prototype in Manzanares was producing around 50 kW on average. The
difference in power output is due to many factors like the cloud coverage, latitude,
actual collector area, the ground not being a black body, effect of shadowing,
difference in the ambient temperature etc.
5. Physical parameters like collector radius, chimney radius and chimney height
were varied and their impact on the power output was observed.
6. Power output increases with increase in each of the above-mentioned parameters,
but the nature of the increment is different. The increment is linear when chimney
height is increased. When plotted against collector radius, the graph is concave
upwards and against chimney radius, it is convex upwards.
7. This type of plant can be established wherever plants are being grown and thus
the land is fully utilised. Also, it can be run at night by storing the heat from
the sun using water or some other means. By doing so, the power generation
during the day would be less when compared to a plant that does not utilise
thermal storage. But the plant can run day and night and produce more power
when averaged over the entire day.
Acknowledgements The authors (K. V. S. T., K. G. and H. T.) wish to express their gratitude to
the School of Mechanical Material and Energy Engineering at Indian Institute of Technology Ropar
for their support.
References
Agarwal A, Kumar P, Mehta B (2018) Solar updraft tower—a potential for future renewable power
generation: a computational analysis. In: Tyagi H, Agarwal AK, Chakraborty PR, Powar S (eds)
Applications of solar energy. Springer, Singapore, pp 319–339
Chitsomboon T (2001) A validated analytical model for flow in solar chimney
Duffie JA, Beckman WA (2003) Solar radiation
Fasel HF, Meng F, Shams E, Gross A (2013) CFD analysis for solar chimney power plants. Sol
Energy 98:12–22
Haaf W (1984) Solar chimneys. Part II: preliminary test results from the Manzanares pilot plant.
Int J Sol Energy 2(2):141–161
Haaf W, Friedrich K, Mayr G, Schlaich J (1983) Part I: principle and construction of the pilot plant
in Manzanares. Int J Sol Energy 2(1):3–20
Incropera FP, Dewitt DP, Bergman TL, Lavine AS (1993) Fundamentals of heat and mass transfer
113
2. In case 2, convective as well as radiative losses through the collector roof were
calculated. Also, the absorptivity and reflectivity of the roof was determined.
Thus, the actual heat flux involved in power generation was calculated for June
and corresponding power output was estimated to be around 74 kW and the
collector efficiency turned out to be nearly 80%. Theoretically, when averaged
over the year, the power output could be around 60 kW, which is around 20%
more than the plant in Manzanares.
3. The peak power output for case 1 was found to be nearly 145 kW and for case
2, it was around 120 kW.
4. The prototype in Manzanares was producing around 50 kW on average. The
difference in power output is due to many factors like the cloud coverage, latitude,
actual collector area, the ground not being a black body, effect of shadowing,
difference in the ambient temperature etc.
5. Physical parameters like collector radius, chimney radius and chimney height
were varied and their impact on the power output was observed.
6. Power output increases with increase in each of the above-mentioned parameters,
but the nature of the increment is different. The increment is linear when chimney
height is increased. When plotted against collector radius, the graph is concave
upwards and against chimney radius, it is convex upwards.
7. This type of plant can be established wherever plants are being grown and thus
the land is fully utilised. Also, it can be run at night by storing the heat from
the sun using water or some other means. By doing so, the power generation
during the day would be less when compared to a plant that does not utilise
thermal storage. But the plant can run day and night and produce more power
when averaged over the entire day.
Acknowledgements The authors (K. V. S. T., K. G. and H. T.) wish to express their gratitude to
the School of Mechanical Material and Energy Engineering at Indian Institute of Technology Ropar
for their support.
References
Agarwal A, Kumar P, Mehta B (2018) Solar updraft tower—a potential for future renewable power
generation: a computational analysis. In: Tyagi H, Agarwal AK, Chakraborty PR, Powar S (eds)
Applications of solar energy. Springer, Singapore, pp 319–339
Chitsomboon T (2001) A validated analytical model for flow in solar chimney
Duffie JA, Beckman WA (2003) Solar radiation
Fasel HF, Meng F, Shams E, Gross A (2013) CFD analysis for solar chimney power plants. Sol
Energy 98:12–22
Haaf W (1984) Solar chimneys. Part II: preliminary test results from the Manzanares pilot plant.
Int J Sol Energy 2(2):141–161
Haaf W, Friedrich K, Mayr G, Schlaich J (1983) Part I: principle and construction of the pilot plant
in Manzanares. Int J Sol Energy 2(1):3–20
Incropera FP, Dewitt DP, Bergman TL, Lavine AS (1993) Fundamentals of heat and mass transfer