Jatropha – a multipurpose non-edible oil yielding shrub, is gaining lot of attention recently. It has been cited as “the best candidate for future bio-diesel production” by Goldman Sacchs in 2007. Recently, it has seen a boom due to incoming of big players and growing interest of the government in renewable energy.

Jatropha is nowadays being seen as a solution to the growing energy demands-former president Dr.A.P.J. Abdul Kalam is himself a staunch supporter of Jatropha cultivation. Jatrpoha seeds contain 27-40% oil, which can be easily extracted. Also, they don’t need to undergo complex processing and treatment. This is among the main reasons as to why it is being considered as a replacement for diesel and other conventional fuels. While the others being:-

• Resistant to drought :- as it requires very little water
• Resistant to pests :- as it is toxic
• Can grow even in wastelands across India, as it doesn’t require very fertile soil.

Out of 476 species of Jatropha known across the world (till date), only 12 species are found in India. It grows well in subtropical and tropical climate and can tolerate extreme temperatures, but not frost.  Also glycerine, the by-product after treatment of seeds, is an important ingredient to cosmetic and pharmaceutical industries.

It is claimed that oil extracted from soya or rape seed etc will offer higher returns than Jatropha. But the cost of seeds of soya and rape is about 4 to 5 times more than that of Jatropha. Further, the soya and rape seeds are already in great demand for edible oil production. Also, they require fertile soil and proper cultivation, while Jatropha can grow even in wastelands.

The above points suggests is that Jatropha can really prove to be a good solution in near future for India. And that’s why it has become a part of India’s goal to achieve energy independence by 2012. Seeing the opportunity, the Government of India has identified 4,00,000 sq. kms of wasteland to grow Jatropha, and thereby reducing the diesel consumption by 20% by the year 2011.

References:-

http://en.wikipedia.org/wiki/Jatropha_oil

Jatropha Production Technology – TamilNadu Agriculture University, Coimbatore

This article basically discusses the environmental impacts of Photovoltaic Technology.  Though most of us think that solar energy is by far the most prominent solution to our energy demands- safe and pure, we overlook certain facts. It’s not that I am against solar-energy but I want to bring the matter to light.

The Albedo Effect

Albedo

The albedo of an object is a measure of how strongly it reflects light from light sources such as the Sun.  It is therefore a more specific form of the term reflectivity. Albedo is defined as the ratio of total-reflected to incident electromagnetic radiation. It is a unit-less measure indicative of a surface’s or body’s diffuse reflectivity.

Causes of Concern

Earth’s average albedo is about 0.3 (i.e. 30% of incoming light is reflected, most of which leaves the atmosphere straight away).  By putting a 0.05 albedo solar panel down on a 0.3 albedo surface, it increases the amount of sunlight that is absorbed by Earth and therefore contributes to warming.  This heat is re-radiated at the Earth’s temperature, in the right wavelength range to be absorbed by greenhouse gases too. If you take an area that was normally light reflective and put a solar panel in it, less light is being reflected and thus more heat is being generated. With roof-top solar panels in desert cities or other hot areas, temperature is bound to increase. That added energy eventually has to heat the surrounding air, which is where the problem came. When wind comes along, it just blows the heat problem next door, in a crowded city.
Consider this, a square foot of black roof solar panel producing say 10% electrical energy from an increased energy influx of say 150W/sqft, is having to use its generated 15W to get rid of the 135W heat load added by the panel to the roof.  This added 135W/sqft eventually will heat the surrounding air [1].  The increase in heat absorption is a one-off climate forcing, equivalent to adding a certain amount of carbon dioxide to the atmosphere.  By comparison, fossil power generation is an ever-increasing climate forcing, since each unit of energy entails the emission of more carbon dioxide. So there is some break-even point beyond which the solar panels help the climate. (more…)