When we are thought about the structure for the azolla growing we come with number of shapes like cylinder cube Tetrahydron, Cone, Hemisphere, Sphere, Prism. We are now stucked with how should be the actual shape must be. In order to go forward we decided to consider some factor which are helpful for growth of azolla. growth like average exposed surface area(AESA) to sunlight, volume loading capacity(VLC), cost of construction, structural stability. The shape which will give best combination of all these properity, we decided to select that for the house for growing azolla. In order to calculate AESA we took help of modelling software SOLIDWORKS. We drawn each of the above geometry and we took 5 planes in order to view the geometry from the space (Shown in below image). That 5 planes represent the position of the sun. We took projection view from that 5 planes that gives us the area available for exposer of sunlight. Obeously the shape which will give higher AESA, is best suited as a structure for azolla. Along with AESA we calculated VLC, cost of construction and structural stability for each of the shape. We decided the priorities for all these parameters ie) AESA and VLC have high priority, Cost of construction has medium priority and Structural stability has lower priority. We assign score for different priority like for high priority, we assign 9 marks, for medium priority 3 marks and for lower priority 1 mark. Also for all parameter we gave score out of 10 and then we multiply that score with the priority score, that gives us total score.

S1; S2; S3; S4; S5 are the position of the sun on the track from east to west. I assume the surface area which is supposed to face the sun at these specific positions during day time. The Different positions (orientations) of Shapes have been mentions with the dimensions. I have not considered the base area or bottom area. The chart that we made is shown below

According to the above analysis, hemisphere has the highest score in importance matrix hence we selected it as the shape for azolla structure.

**Higher
energy capture**

An advantage of a hemisphere is it has a maximum average exposed surface area to the sun during the day time. By calculation for a Hemisphere resting in the ground on its plane face, the AESA is 70% of its total surface area. Which is higher compared to other competing shapes.

**Higher Volumetric Capacity**

It also gives the maximum Volumetric loading capacity as it has maximum volume occupied for a given surface area. This allows us to process bulk quantities in similar cycle times. This increases the throughput of the system

**Cost wise Advantage**

The Construction cost of the hemisphere is less, as less material is required to enclosed design volume.