Synopsis of our project :))
OUR IDEA :
Generally desert is conceived to be just barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life.
Our project aims at making use of this barren land and salty water from the seas which is otherwise considered useless along with the solar energy to create self sustaining, economical and realistic way of producing food which has the potential to impact the lives of millions of people living in water-starved areas around the world by making greenhouses in sub tropical deserts near seas and oceans by using natural cycle of water.
1. Salty water which is assumed to be useless.
2. Deserts which is hostile for plants and animal life.
3. Sunlight which is abundant in these sub tropical deserts.
1.High Quality All year round crops.
2. No pesticides required: The honeycomb evaporator filters out pollen and pests that are killed by the saline water so the greenhouse doesn’t need much pesticide
3.Low operating costs:its operating costs are 10 to 25 percent less than those of a traditional greenhouse. Its fixed costs are 10 to 15 percent less because it doesn’t need to purchase cooling, heating, or desalination equipment, and because it is usually built on cheap land where little can grow.
4. Brine solution: Nutrients harvested from the brine are pumped back into the irrigation system and rest of it is sold as salt.
5. Fresh Water
6. The system is powered by CSP unit which produces more electricity than needed.
7. Reverse the desertification (Humid Air and Biological waste):Biological waste can be converted to compost and the humid air that comes out of the greenhouse helps provides a suitable environment for the growth of nearby plants grown that can survive on sea water.This can actually solve one of the biggest problems “deserts” and make them suitable for living.
8. Reduction in the amount of greenhouse gases.
9. Solves the problem of water scarcity.
CSP vs. Solar panels.
a).CSP gives us pure water along with clean energy, thus fulfilling one of the cornerstone ideologies of our project.
b).CSP uses heated molten salt, which can retain heat for a very long while.
c).CSP is more efficient on a large scale basis.
Some additional benifits :D
Our sustainable system is clean, efficient, and elegant in its design. The greenhouse control system, pumps and fans are powered by electricity produced completely by CSP (Concentrated Solar Power) Unit .
The electricity that is produced is more than what the greenhouse needs and hence if a large number of greenhouses are installed, it can be used to make an extra profit .The honeycomb evaporator filters out pollen and pests that are killed by the saline water so the greenhouse doesn’t need much pesticide. Nutrients harvested from the brine are pumped back into the irrigation system to fertilize the crops, and the rest of the salt is made into gourmet salt crystals.
Because the greenhouse produces its own fresh water, and uses no fossil fuels or pesticides, its operating costs are 10 to 25 percent less than those of a traditional greenhouse. Its fixed costs are 10 to 15 percent less because it doesn’t need to purchase cooling, heating, or desalination equipment, and because it is usually built on cheap land where little can grow .This technology works best in arid regions by the sea, and near consumer markets so crops can be easily transported.
Areas of Europe such as Crete, France, Greece, Italy, Portugal and Spain; California and Mexico in North America; large parts of China, India, Pakistan and Turkey in Asia; and much of Australia, the Middle East and northern Africa, are good candidates for this project .Also, this project can be further extended to the production of cattle and fishes.
One of the most alarming dilemmas that erupts in increasing agricultural production is the one related to the energy guzzling nature of agricultural activities. Agricultural activities use enormous amount of energy. In traditional crop production, the energy is usually derived from fossil fuels. This contributes significantly to the world's carbon footprint instigating a further rise in global temperatures. With every rise in degree Celsius, there is a 10% decrement in the world's agricultural produce. This hence forms a vicious cycle. The inevitable effect of increasing agricultural production is fall in the production itself. Another major drawback of increasing the agricultural produce is its voracious water requirement .We developed project Sandmare as a remedy to all such problems posed by traditional farming methods.
We know it’s an ambitious project but ambitious is what we must be.
The Working of our project :D
Sandmare provides an economical and sustainable way of producing fresh water and crops in hot, dry regions near the ocean.It has the potential to impact on the lives of millions of people living in water-starved areas around the world.It produces crops year-round in hot dry areas using only seawater and sunlight. Tomatoes, cucumbers, peppers, lettuce, strawberries, herbs—anything that can be grown in traditional greenhouses—can be grown in seawater greenhouse.
There are 2 major units:
2. PWSP(Power Water Salt Production) Unit
GREENHOUSE : The greenhouse is the part from which we get pesticide free high quality food all year round. The key elements of the greenhouse are :
(A) Semi porous walls : The greenhouse has 2 semi porous walls and the sea water is allowed to perculate through these semi porous walls. Since the temperature outside the greenhouse is pretty high(around 40-50 degree celsius ) the process of evaporation makes the air inside more humid and the temperature is reduced.The salt left on the walls has a sterlising effect thus,there is no need of pesticides.
(B) Transparent Walls :To ensure maximum sunlight two walls are made up of transparent material.
(C) Transparent Roof : It ensures maximum sunlight.
(D) Exhaust Fans : Exhaust Fans ensure that low pressure is maintained inside the greenhouse.
(E) Separate Compartments : There are separate compartments for the plants so as to prevent any spread of disease.
The greenhouse operates on Concentrated Solar Power (CSP). This is a technique to harvests solar power without the use of expensive and delicate solar panels.
The key elements of this technique are:
(a) Semi cylindrical mirrors : They concentrate sunlight on a pipe running through their foci. This pipe contains molten salt. The concave mirrors are placed along the North-South axis (same as the greenhouse) and rotate with the sun to always face it directly.
(b) The molten salt:It is used as it has very high heat retaining capacity and boiling point. This allows it to attain temperatures ranging to 600 degree celsius. The high retention capability allows us to store the heated molten salt and use it after nightfall.The Molten salt is basically sodium nitrate which is obt from sea water which makes the system independent. The heated molten salt is taken to a chamber called PWSP (Power Salt Water Production) unit.
PWSP UNIT :
The key elements of PWSP UNIT:
(A) Coil and pressurized chamber: A coil is placed around a pressurized chamber containing cold saline sea water. The heated molten salt runs through the coil. This turns the sea water in the chamber to vapor.
(B) Turbine :The pressurized steam is guided to the turbine using another set of pipes. The pressurized steam turns the turbine to produce electricity just like in any traditional power plant.
(C) Array of pipes: steam is further condensed to obtain pure water using an array of pipes having cold sea water. This pure water can be used not only to serve the greenhouse's needs but could also be used to curb water deficiency in the world.