The ecological footprint

The ecological footprint is an indicator of the environmental impact generated by humans. Crudely, it is the effect we are producing on land based on inadequate, disrespectful and extreme exploitation of its resources.

The ecological footprint is expressed as the surface needed to produce the resources consumed by an average of a certain human community citizen, as well as the necessary to absorb the waste generated, regardless of the location of these areas.

We exploit the fields, forests, the sea... without leaving a space of time so you can regenerate itself, we do not give an only rest to land above the respect it is own economic good.

The calculation of the ecological footprint is based on the impact that makes each mode or way of life, i.e. communities of human on the planet by comparing it with its capacity.

This calculation is based on:
Certain materials and energy, as all existing products, have their origin in ecological systems are needed to produce any product.In turn, become need ecological systems to reabsorbed waste that we have created to obtain our product or to use it.Later, fill all infrastructures that occupy the space needed for productive ecosystems.The calculation of the ecological footprint is complex and its data are often underestimated the real impact of human activity by the lack of available information.

Here, we show you the data from the calculation of the ecological footprint that took place in a study of 2003 at the global level (Semarnat, 2007)

In it you can see which activities are those more ecological footprint have generated in the population. To understand the result, keep in mind that have spoken earlier, the bases of calculation:
47.5% Burning fossil fuels22.0% agriculture7.6% wood, pulp and paper.6.7% Fishing6.3% livestock3.6% Nuclear energy3.6% urban settlements2.7% LeñaLa obtaining ecological footprint has made it possible to compare two completely different worlds under one common denominator, its impact to the environment. It allows us to see two closely related realities:

The first observation allows us to see the way of life of the rich countries of the planet can not to expand to the rest of its inhabitants.

While the second, if we talk in terms of sustainable global economy, the wealthy minority would have to reduce their consumption and their standard of living because there would be no sufficient planet that everyone lived as a well-off European citizen because of the exploitation of the resources based on the availability of fossil fuels.

That leaves us in conclusion, that the much of the developed countries ecological footprint exceeds exorbitant way its own surface, given the resources and discharges of waste extraction in places far removed from its territory.



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Solar cells cheaper and more efficient with low-quality Silicon

We told you of a new line of innovation in manufacturing of photovoltaic solar cells seems to reach one of the most important objectives for future of solar energy approach: increase efficiency and reduce the cost of the electricity generation.

Singapore researchers have taken advantage of the advanced technology that has developed in the creation of nanostructures to make a highly efficient Silicon cell and still cheaper. With this development, the researchers hope that the cost of solar energy can be reduced by half, which could certainly mean the opening of the renewable to millions of people in the world.

This development was carried out jointly by the University of technology of Nanyang (NTU) and the to * STAR Institute of microelectronics (IME). These new thin film solar cells using Silicon low-quality, a cheaper material, allowing a low final price. Exceptional for his invention is that they have found a technique which can generate electricity flows similar to those produced by traditional solar cells that contain such expensive high quality Silicon.

The new nano-estructuradas solar cells NTU-A * STAR can produce a stream of (34.3mA/cm2) - a world record for a solar cell of Silicon of class. This is possible through the creation of a unique texture using nanostructures on the surface of the solar cell, which are thousands of times smaller than a human hair.
To compare the resulting electrical current with the results of other types of solar cells, we can see it quite close to the traditional cells which is 40mA/cm2. While the conventional solar thin film cells typically produce about half of this stream.

The adoption of solar energy worldwide is hampered in large part by the high cost of traditional solar panels , and this is because they are made with high quality Silicon. To rectify this, has been used - as you had above - to low-quality amorphous silicon , a thin film has no texture-- which is 100 times thinner. However this material - is its natural form - is not as effective to convert sunlight into electricity, so it produces less energy.

The developed method is then to create a unique texture on the surface of amorphous, Silicon using nanostructures and thus improves the efficiency of conversion of energy (PCE) of thin film silicon cell and therefore increases the production of energy.
More about high efficiency solar cells:
Solar energy could have its future in the colder regions of the planet
Solar cells with efficiency of 45 %
High efficiency solar cells
A Virus improves the efficiency of solar cells
Solar Cell film fine record of 28.2% efficiency




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