I was surprised by the number of tomatoes that appeared on this shrub on my rooftop organic garden. I really don't know much about gardening, just decided to experiment a bit. What is the proper way to make compost? What I do is just bury vegetable waste in soil-it seems to work - and there is no smell and attract no flies.
Plastic netting is available which can act as sun screen. I am experimenting with this, though I am not entirely satisfied about its potential. In Trivandrum, India, where I live, frequently there is cloud cover, there is frequent rain, and for about four months in a year there is blazing sun. I am planning to try planting sun loving and shade loving plants together so they can support one another.
As you can see my rooftop is practically bare at the moment. If I had adequate knowledge and utilized the full extent of my rooftop I could provide my family a good fraction of the vegetables we consume. Over my staircase roof, which is at a higher level, there is also enough area for 10 sq meters of solar panel!
Selvaraj
home
I left out one thing: this is also a place where you can do solar cooking.
ReplyDeleteMy roof top activities (total area around 1000 sq ft):
1. Presently have three raised beds of dimension 6 feet x 1.5 feet (with 9 inches soil). Total 27 sq feet. Out of this (because of wrong layout) there is excessive shading in half the portion; I use this area for composting. Plan to bring total raised bed area to 100 sq ft shortly.
2. Just last week I covered around 350 sq ft with a roof for a sit out. Total cost Rs 34,000.
3. Rainwater from the sit out roof is brought to two 500 litre tanks - for rainwater harvesting. I am hoping to cut my water bill in half. In Trivandrum it rains for around 7 to 8 months in a year.
4. Plan to install a solar cooker with 1.2 m x 1.2 m parabolic reflector. The solar cooker was just delivered - yet to be opened and assembled.
5. Ample place for solar panels over the sit out roof.
Selvaraj
On 14 November 2011 22:08, xxx wrote:
ReplyDeleteAccording to internet sources, area of India is 3287263 Km^2 and 43% is used for agriculture, giving approx 1.4E6 Km^ of agricultural land. Would increasing this by .3% increase GDP by "tens of thousands of crores" ?
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Well, my 'tens of thousands of crores' was somewhat rhetorical. However, since you have posed the question let us calculate and see what figures we obtain.
1. Solar power on 10% of available roof top area:
- Total area available 500 sq Km. On this we can produce 50,000 Mw of power for four hours every day.
- No of units produced in an hour = 50,000,000
- At the rate of Rs 5/unit (I am cheating a little here :-), the value of electricity generated = Rs 250,000,000 = Rs 25 crores/hour
- For a day the income will be Rs 100 crores
- In a year Rs 36,500 crores.
2. Vegetable cultivation on 20% of available roof top area:
Lets keep in mind that the rooftop will be considerably more productive than an average farmer's field due to better drainage and less pathogens. Since 'farming' is done is less area it will also be economical to use high tech techniques like drip irrigation, green house etc. My estimate is that it should be easily possible to harvest one kg of vegetables per day from 200 sq ft of raised bed cultivation on a rooftop (In India).
- Total area available 1000 sq Km.
- One Kg of vegetables produced on 20 sq m / day
- Vegetables produced from an area of 1000 sq km = 1000,000,000/20 = 50,000,000 Kg / day
- At the rate of Rs 20/kg (we seem to be paying about this much in Trivandrum) this works out to 1000,000,000 Rs
- Or Rs 100 crores / day
- In a year this works out to Rs 36,500 crores.
* Using 30% of the roof area we have already reached Rs 73,000 crores!
Please note, the value of using rooftops goes beyond GDP figures.
1. We are going to face serious problems in the availability of fertilizers in future; Its cost is already zooming. In the home environment, fertilizer will be available from recycled waste.
2. Fresh vegetables, from which nutrients have not been sapped out.
3. Poor people need not spend on common vegetables.
4. Decentralization will lead to more sharing of wealth.
Regards,
Selvaraj