The concept of using animal dung to generate energy isn't new – people having been using animal waste to generate electricity since centuries. In fact, Marco Polo has mentioned the use of covered sewage tanks in ancient China believed to be dated back 2,000 – 3,000 years ago! Animal dung or animal manure refers to the undigested fecal matter that has passed through an animal's gut, usually of the bovine animal species such as cattle/cows, yak, buffalo etc.

In under-developed countries like India and Pakistan, some farmers are already using the biogas (also called gobar gas) produced by cow dung to generate power. It is estimated that biogas facilities exist in more than two million households in India and in hundreds of thousands in Pakistan, mostly in North Punjab, due to the booming population of livestock.

A recent study has shown that the microbes in about half a liter of rumen fluid (fermented, liquefied feed extracted from the largest chamber in the cow's stomach) can produce approximately 600 millivolts of electricity–about half the electricity required to run one AA-sized battery!

Although producing biogas requires costly equipment, the farmers in rural areas have devised their own simple and eco-friendly equipment to extract methane gas from animal dung. The method involves the making of slurry which is a mixture of animal manure and waste water.

The slurry is put in an air-tight pit or an air-tight tank which is called a digester and has a pipe connection attached to it. The slurry is made to go through a bio-chemical process called the anaerobic digestion process, in which microorganisms break down the biodegradable material (in the absence of oxygen) to produce methane and carbon dioxide at the end. The gas produced is transferred to the kitchen fireplace through pipes and control valves or to generate electricity for lighting up bulbs.

Seeing the success stories of other countries, Western countries have been greatly inspired to go a little ahead of there counterparts. For example, the Rosamond Gifford Zoo in Syracuse, New York wants to be the first zoo in the US to supplement its energy needs with power from animal dung. Since the Zoo is home to a successful Asian elephant breeding program, they have quite a few elephants living together. Their total waste production can top 1000 pounds of dung per day, and the Zoo's yearly animal waste costs 10,000 dollars to dispose of. At the same time, much of the waste from vegetarian animals at the Zoo is indigestible plant fiber – a high energy fuel.

The Zoo's proposed projects entail using the animal dung to generate methane or hydrogen, and then using that biogas/fuel to generate electricity. Although the process has worked around the world, its suitability for use at the zoo is still being studied. Whatever the result maybe, it's indeed exciting to know that creative energy alternatives are been finally explored.

Digital Subscriber Line (DSL) is the technology that provides digital data transmission through local telephone network. Now the term digital subscriber line has been widely adopted by IT professionals as a more marketing-friendly term for Asymmetric Digital Subscriber Line (ADSL). Usually the download speed of consumer DSL services ranges from 256Kbps to 20Mbps depending on DSL technology, line conditions, and services.  Typically download speed is much higher than download speed for ADSL, and for Symmetric Digital Subscriber Line (SDSL) upload and download speed remains the same. 

Data-transmission rate differ depending on the line-length from telephone exchange to subscriber. Many technologies are implemented globally to provide maximum internet speed to subscriber, here are brief introduction of advanced DSL technologies:

ISDN Digital Subscriber Line (IDSL) –  ISDN based technology is being used to provide higher data flow as compared to dual channel ISDN. 

High Data Rate Digital Subscriber Line (HDSL / HDSL2) – known as the first DSL technology that uses a higher frequency spectrum of copper and twister pair cables. 

Symmetric Digital Subscriber Line (SHDSL / SDSL) – data transfer volume for download and upload remains the same by using this technology. 

Asymmetric Digital Subscriber Line (ADSL) – by using this technology the volume of data flow is greater in one direction than the other.

Asymmetric Digital Subscriber Line 2 (ADSL2) – it is the improved version of ADSL

Asymmetric Digital Subscriber Line 2 Plus (ADSL2+) – it is the next version of ADSL2 that doubles the data rates by using twice the spectrum.

Asymmetric Digital Subscriber Line Plus Plus (ADSL++) – an advanced technology developed by Centillium Communications. This technology was adopted for the Japanese market that extends downstream rates to 50 Mbit/s by using spectrum up to 3.75 MHz.

Rate-Adaptive Digital Subscriber Line (RADSL) – technology was designed to increase range and noise tolerance by sacrificing up stream speed.

Very High Speed Digital Subscriber Line (VDSL)

Very High Speed Digital Subscriber Line 2 (VDSL2), an improved version of VDSL

Uni-DSL (UDSL or Uni Digital Subscriber Line), Texas Instruments developed this technology

Gigabit Digital Subscriber Line (GDSL) – based on binder MIMO technologies.

Universal High bit rate Digital Subscriber Line (UHDSL) – use fiber optics, in 2005 RLH Industries, Inc. developed this technology.  

Computer Basics : What Is a DSL Modem?

Load shedding in Pakistan have made everyone’s life miserable. Students can’t play computer games, browse internet, and make their assignments during black-outs and professionals can’t impress their bosses, as if there’s not electricity they won’t be able to complete their home work on time.

Above posted video is a solution for all suffers, watch the video and you will learn how to build a 48 hour backup computer power supply with the help of tiny car batter.

Caution: Batteries contains acids and injurious gases and they can be explosives. Don’t let children play with the high voltage equipments. If there mistake happens, thing can get worse.