GreenIdeas

How to survive the coming century

2009-03-02T21:54:00.000-08:00

25 February 2009 by Gaia Vince

ALLIGATORS basking off the English coast; a vast Brazilian desert; the mythical lost cities of Saigon, New Orleans, Venice and Mumbai; and 90 per cent of humanity vanished. Welcome to the world warmed by 4 °C.
Clearly this is a vision of the future that no one wants, but it might happen. Fearing that the best efforts to curb greenhouse gas emissions may fail, or that planetary climate feedback mechanisms will accelerate warming, some scientists and economists are considering not only what this world of the future might be like, but how it could sustain a growing human population. They argue that surviving in the kinds of numbers that exist today, or even more, will be possible, but only if we use our uniquely human ingenuity to cooperate as a species to radically reorganise our world.
The good news is that the survival of humankind itself is not at stake: the species could continue if only a couple of hundred individuals remained. But maintaining the current global population of nearly 7 billion, or more, is going to require serious planning.
Four degrees may not sound like much - after all, it is less than a typical temperature change between night and day. It might sound quite pleasant, like moving to Florida from Boston, say, or retiring from the UK to southern Spain. An average warming of the entire globe by 4 °C is a very different matter, however, and would render the planet unrecognisable from anything humans have ever experienced. Indeed, human activity has and will have such a great impact that some have proposed describing the time from the 18th century onward as a new geological era, marked by human activity. "It can be considered the Anthropocene," says Nobel prizewinning atmospheric chemist Paul Crutzen of the Max Planck Institute for Chemistry in Mainz, Germany.
A 4 °C rise could easily occur. The 2007 report of the Intergovernmental Panel on Climate Change, whose conclusions are generally accepted as conservative, predicted a rise of anywhere between 2 °C and 6.4 °C this century. And in August 2008, Bob Watson, former chair of the IPCC, warned that the world should work on mitigation and adaptation strategies to "prepare for 4 °C of warming".
A key factor in how well we deal with a warmer world is how much time we have to adapt. When, and if, we get this hot depends not only on how much greenhouse gas we pump into the atmosphere and how quickly, but how sensitive the world's climate is to these gases. It also depends whether "tipping points" are reached, in which climate feedback mechanisms rapidly speed warming. According to models, we could cook the planet by 4 °C by 2100. Some scientists fear that we may get there as soon as 2050.
If this happens, the ramifications for life on Earth are so terrifying that many scientists contacted for this article preferred not to contemplate them, saying only that we should concentrate on reducing emissions to a level where such a rise is known only in nightmares.
"Climatologists tend to fall into two camps: there are the cautious ones who say we need to cut emissions and won't even think about high global temperatures; and there are the ones who tell us to run for the hills because we're all doomed," says Peter Cox, who studies the dynamics of climate systems at the University of Exeter, UK. "I prefer a middle ground. We have to accept that changes are inevitable and start to adapt now."
Bearing in mind that a generation alive today might experience the scary side of these climate predictions, let us head bravely into this hotter world and consider whether and how we could survive it with most of our population intact. What might this future hold?
The last time the world experienced temperature rises of this magnitude was 55 million years ago, after the so-called Palaeocene-Eocene Thermal Maximum event. Then, the culprits were clathrates - large areas of frozen, chemically caged methane - which were released from the deep ocean in explosive belches that filled the atmosphere with around 5 gigatonnes of carbon. The already warm planet rocketed by 5 or 6 °C, tropical forests sprang up in ice-free polar regions, and the oceans turned so acidic from dissolved carbon dioxide that there was a vast die-off of sea life. Sea levels rose to 100 metres higher than today's and desert stretched from southern Africa into Europe.
While the exact changes would depend on how quickly the temperature rose and how much polar ice melted, we can expect similar scenarios to unfold this time around. The first problem would be that many of the places where people live and grow food would no longer be suitable for either. Rising sea levels - from thermal expansion of the oceans, melting glaciers and storm surges - would drown today's coastal regions in up to 2 metres of water initially, and possibly much more if the Greenland ice sheet and parts of Antarctica were to melt. "It's hard to see west Antarctica's ice sheets surviving the century, meaning a sea-level rise of at least 1 or 2 metres," says climatologist James Hansen, who heads NASA's Goddard Institute for Space Studies in New York. "CO2 concentrations of 550 parts per million [compared with about 385 ppm now] would be disastrous," he adds, "certainly leading to an ice-free planet, with sea level about 80 metres higher... and the trip getting there would be horrendous."

Alternative Power Source

2009-03-02T21:16:00.001-08:00

Alternative power Sources

Alternative fuels, also known non-conventional fuels, are any materials or substances that can be used as a fuel, other than conventional fuels. Conventional fuels include: fossil fuels (petroleum (oil), coal, propane, and natural gas), and nuclear materials such as uranium.

Some well known alternative fuels include biodiesel, bioalcohol (methanol, ethanol, butanol), chemically stored electricity (batteries and fuel cells), hydrogen, non-fossil methane, non-fossil natural gas, vegetable oil and other biomass sources.

1.Bio-diesel:

Biodiesel refers to a non-petroleum-based diesel fuel consisting of long chain alkyl (methyl, propyl or ethyl) esters, made by transesterification of vegetable oil or animal fat (tallow), which can be used (alone, or blended with conventional petrodiesel) in unmodified diesel-engine vehicles. Biodiesel is distinguished from the straight vegetable oil (SVO) (sometimes referred to as "waste vegetable oil", "WVO", "used vegetable oil", "UVO", "pure plant oil", "PPO") used (alone, or blended) as fuels in some converted diesel vehicles.
"Biodiesel" is standardized as mono-alkyl ester and other kinds of diesel-grade fuels of biological origin are not included.

2.Bioalcohol
A. Methanol and Ethanol

Ethanol used as a fuel.
Main articles: Methanol fuel, Ethanol fuel
Methanol and ethanol can both be derived from fossil fuels or from biomass. Ethanol is produced through fermentation of sugars and methanol from synthesis gas.
As a fuel methanol and ethanol both have advantages and disadvantages over fuels such as petrol and diesel. In spark ignition engines both alcohols can run at a much higher EGR rates and with higher compression ratios. Both alcohols have a high octane rating, with ethanol at 129 RON, 102 MON, (which equates to 116 AKI) and methanol at 123 RON, 103 MON (which equates to 113 AKI) . Ordinary European petrol is typically 95 RON, 85 MON, equal to 90 AKI. Note that AKI refers to 'Anti-Knock Index' which averages the RON and MON ratings (RON+MON)/2, and is used on U.S. gas station pumps. As a compression ignition engine fuel, both alcohols create very little particulates, but their low cetane number means that an ignition improver like glycol must be mixed into the fuel with approx. 5%.
With SI engines alcohols have the potential to reduce NOx, CO, HC and particulates. A test with E85 fueled Chevrolet Luminas showed that NMHC went down by 20-22%, NOx by 25-32% and CO by 12-24% compared to reformulated gasoline. Toxic emissions of benzene and 1,3 Butadiene also decreased while aldehyde emissions increased (acetaldehyde in particular).
Tailpipe emissions of CO2 also decrease due to the lower carbon-to-hydrogen ratio of these alcohols, and the improved engine efficiency.
Methanol and ethanol contain soluble and insoluble contaminants . Halide ions, which are soluble contaminants, such as chloride ions, have a large effect on the corrosivity of alcohol fuels. Halide ions increase corrosion in two ways: they chemically attack passivating oxide films on several metals causing piting corrosion, and they increase the conductivity of the fuel. Increased electrical conductivity promotes electrical, galvanic and ordinary corrosion in the fuel system. Soluble contaminants such as aluminum hydroxide, itself a product of corrosion by halide ions, clogs the fuel system over time. To prevent corrosion the fuel system must be made of suitable materials, electrical wires must be properly insulated and the fuel level sensor must be of pulse and hold type (or similar). In addition, high quality alcohol should have a low concentration of contaminants and have a suitable corrosion inhibitor added.
Methanol and ethanol are also incompatible with some polymers. The alcohol is solved by the polymers causing swelling, and over time the oxygen breaks down the carbon-carbon bonds in the polymer causing a reduction in tensile strength. For the past few decades though, most cars have been designed to tolerate up to 10% ethanol (E10) without problem. This include both fuel system compatibility and lambda compensation of fuel delivery with fuel injection engines featuring closed loop lambda control. In some engines ethanol may degrade some compositions of plastic or rubber fuel delivery components designed for conventional petrol, and also be unable to lambda compensate the fuel properly.[citation needed]
"FlexFuel" vehicles have upgraded fuel system and engine components which are designed for long life using E85 or M85, and the ECU can adapt to any fuel blend between gasoline and E85 or M85. Typical upgrades include modifications to: fuel tanks, fuel tank electrical wiring, fuel pumps, fuel filters, fuel lines, filler tubes, fuel level sensors, fuel injectors, seals, fuel rails, fuel pressure regulators, valve seats and inlet valves. The cost of this E85 upgrade to a modern engine is inexpensive and is less than $100[citation needed]. "Total Flex" Autos destined for the Brazilian market can use E100 (100% Ethanol).
One liter of ethanol contain 21.1 MJ, a liter of methanol 15.8 MJ and a liter of gasoline approximately 32.6 MJ. In other words, for the same energy content as one liter or one gallon of gasoline, one needs 1.6 liters/gallons of ethanol and 2.1 liters/gallons of methanol. Although actual fuel consumption doesn't increase as much as energy content numbers indicate.
Methanol has been proposed as a future biofuel. Methanol has a long history as a racing fuel. Early Grand Prix Racing used blended mixtures as well as pure methanol. The use of the fuel was primarily used in North America after the war.{What war?} However, methanol for racing purposes has largely been based on natural gas and therefore would not be considered as biofuel. Methanol is an excellent biofuel and compared to ethanol its primary advantage is its much greater well-to-wheel efficiency when produced from syngas.
Ethanol is already being used extensively as a fuel additive, and the use of ethanol fuel alone or as part of a mix with gasoline is increasing. Compared to methanol its primary advantage is that the fuel is non-toxic, although the fuel will produce some toxic exhaust emissions. From 2007, the Indy Racing League will use ethanol as its exclusive fuel, after 40 years of using methanol. Since September 2007 petrol stations in NSW, Australia are mandated to supply all their petrol with 2% Ethanol content
Methanol combustion is: 2CH3OH + 3O2 → 2CO2 + 4H2O + heat
Ethanol combustion is: C2H5OH + 3O2 → 2CO2 + 3H2O + heat

B. Butanol
Main article: Butanol fuel
Propanol and butanol are considerably less toxic and less volatile than methanol. In particular, butanol has a high flashpoint of 35 °C, which is a benefit for fire safety, but may be a difficulty for starting engines in cold weather. The concept of flash point is however not directly applicable to engines as the compression of the air in the cylinder means that the temperature is several hundred degrees Celsius before ignition takes place.
The fermentation processes to produce propanol and butanol from cellulose are fairly tricky to execute, and the Weizmann organism (Clostridium acetobutylicum) currently used to perform these conversions produces an extremely unpleasant smell, and this must be taken into consideration when designing and locating a fermentation plant. This organism also dies when the butanol content of whatever it is fermenting rises to 7%. For comparison, yeast dies when the ethanol content of its feedstock hits 14%. Specialized strains can tolerate even greater ethanol concentrations - so-called turbo yeast can withstand up to 16% ethanol . However, if ordinary Saccharomyces yeast can be modified to improve its ethanol resistance, scientists may yet one day produce a strain of the Weizmann organism with a butanol resistance higher than the natural boundary of 7%. This would be useful because butanol has a higher energy density than ethanol, and because waste fibre left over from sugar crops used to make ethanol could be made into butanol, raising the alcohol yield of fuel crops without there being a need for more crops to be planted.
Despite these drawbacks, DuPont and British Petroleum have recently announced that they are jointly to build a small scale butanol fuel demonstration plant alongside the large bioethanol plant they are jointly developing with Associated British Foods.
Energy Environment International developed a method for producing butanol from biomass, which involves the use of two separate micro-organisms in sequence to minimize production of acetone and ethanol byproducts.
The Swiss company Butalco GmbH uses a special technology to modify yeasts in order to produce butanol instead of ethanol. Yeasts as production organisms for butanol have decisive advantages compared to bacteria.
Butanol combustion is: C4H9OH + 6O2 → 4CO2 + 5H2O + heat
The 3-carbon alcohol, propanol (C3H7OH), is not used as a direct fuel source for petrol engines that often (unlike ethanol, methanol and butanol), with most being directed into use as a solvent. However, it is used as a source of hydrogen in some types of fuel cell; it can generate a higher voltage than methanol, which is the fuel of choice for most alcohol-based fuel cells. However, since propanol is harder to produce than methanol (biologically OR from oil), methanol fuel cells are still used a lot more often than those that utilise propanol.

Source:http://en.wikipedia.org/wiki/Biodiesel
http://en.wikipedia.org/wiki/Bioalcohol#Methanol_and_Ethanol

GreenIdeas Articles

2009-02-23T22:20:00.000-08:00

Green Ideas Starts With Green Computing

Nowadays Computer play a vast role in our daily life. Many organizations try to restrict on using hazardous substances like in electrical parts of computer, not just banning hazardous substances but also making electrical products as energy efficient without compromising performance.

Energy efficient machines are very important nowadays due to rising of fuel cost used to generate electricity. Nowadays cooling is playing a vast role to electronic products especailly in the processor, processors generate excessive heat when under heavy loads and heavy loads is equal to higher energy consumption, nowadays electronic manufacturers are trying to make to computers energy efficient like DELL corporation.

Making electronic products clean is not an easy to achieve, I think its very hard to make it hazardous free while maintaining its features, So some Companies are just trying to reduce it, Like AMD said:

"Although lead containing solder cannot be completely eliminated from all applications today, AMD engineers have developed effective technical solutions to reduce lead content in microprocessors and chipsets to ensure RoHS compliance while minimizing costs and maintaining product features. There is no change to fit, functional, electrical or performance specifications. Quality and reliability standards for RoHS compliant products are expected to be identical compared to current packages." Source: http://www.wikipedia.com/

Computers nowadays are not just energy efficient but also reducing its hazardous substances in its electronic parts,
One of the organizations who tries to restrict hazardous materials is RoHs(Restriction on Hazardous Substances). Because of their effort, many Electronic companies tried to follow their footsteps on green computing. RoHs compliant Companies brought our technology to the next level, not just making them less hazardous but also making it energy efficient without compromising the performance. Electronic companies does not exactly removes all hazardous substances because there are still hazardous substances that is very important to electronic hardwares, Many scientist today are still inventing or researching to replace hazardous substances without compromising the performance.

Based on Wikipedia

Reliability Concerns:

An illustration of solder joint reliability, demonstrating AlphaSTAR's reliability versus traditional joints. AlphaSTAR is a RoHS immersion silver PWB assembly process from Cookson Electronics. Copyright 2007 © Enthone Inc.
Contrary to the predictions of widespread component failure and reduced reliability, RoHS's first anniversary (July 2007) passed with little fanfare. Today, millions of compliant products are in use worldwide. Some of the most popular consumer electronics are now RoHS compliant, examples include Apple's iPod portable music players, Dell and HP home computers and servers, and Motorola's RAZR wireless phones.
Many electronics companies keep "RoHS status" pages on their corporate websites. For example, the AMD website states:
"Although lead containing solder cannot be completely eliminated from all applications today, AMD engineers have developed effective technical solutions to reduce lead content in microprocessors and chipsets to ensure RoHS compliance while minimizing costs and maintaining product features. There is no change to fit, functional, electrical or performance specifications. Quality and reliability standards for RoHS compliant products are expected to be identical compared to current packages."RoHS printed circuit board finishing technologies are surpassing traditional formulations in fabrication thermal shock, solder paste printability, contact resistance, and aluminum wire bonding performance and nearing their performance in other attributes. One of these finishing products, known as immersion silver, is depicted here.
The properties of lead-free solder, such as its high temperature resilience, has been used to prevent failures under harsh field conditions. These conditions include 150°C operating temperatures with test cycles in the range of -40°C - 150°C with severe vibration and shock requirements. Automobile manufacturers are turning to RoHS solutions now as electronics move into the engine bay.

Flow properties and assembly
One of the major differences between lead-containing and lead-free solder pastes is the "flow" of the solder in its liquid state. Lead-containing solder has higher surface tension, and tends to move slightly to attach itself to exposed metal surfaces that touch any part of the liquid solder. Lead-free solder conversely tends to stay in place where it is in its liquid state, and attaches itself to exposed metal surfaces only where the liquid solder touches it.
This lack of "flow" -- while typically seen as a disadvantage because it can lead to lesser quality electrical contacts -- can be used to place components tighter than they normally could be placed due to the properties of lead-containing solders.
For example, Motorola reports that their new RoHS wireless device assembly techniques are "...enabling a smaller, thinner, lighter unit." Their Motorola Q phone would not have been possible without the new solder. The lead-free solder allows for tighter pad spacing.[54]

Some exempt products achieve compliance
Research into new alloys and technologies is allowing companies to release RoHS products that are currently exempt from compliance, e.g. computer servers.[ IBM has announced a RoHS solution for high lead solder joints once thought to remain a permanent exemption. The lead-free packaging technology "...offers economical advantages in relation to traditional bumping processes, such as solder waste reduction, use of bulk alloys, quicker time-to-market for products and a much lower chemical usage rate."
Test and measurement vendors, such as National Instruments, have also started to produce RoHS-compliant products, despite devices in this category being exempt from the RoHS directive. Source: http://www.wikipedia.com/

Health benefits
RoHS helps reduce damage to people and the environment in third-world countries where much of today's "high-tech trash" ends up. The use of lead-free solders and components has provided immediate health benefits to electronics industry workers in prototype and manufacturing operations. Contact with solder paste no longer represents the same health-hazard it did before. Source: http://www.wikipedia.com/

Criticism:

Criticism
Adverse effects on product quality and reliability, plus high cost of compliance (especially to small business) are cited as criticisms of the directive, as well as research indicating that the life cycle effect of lead-free solder is more significant than that of traditional solder materials.[citation needed]One criticism of RoHS is that the restriction of lead and cadmium does not address some of their most prolific applications, while being costly for the electronics industry to comply with. Specifically, the total lead used in electronics makes up only 2% of world lead consumption, while 90% of lead is used for batteries (covered by the battery directive, as mentioned above, which requires recycling and limits the use of mercury and cadmium, but does not restrict lead). Another criticism is that less than 4% of lead in landfills is due to electronic components or circuit boards, while approximately 36% is due to leaded glass in monitors and televisions, which can contain up to 2kg per screen.
Restricting lead content in solder for electronics requires expensive retooling of assembly lines and different coatings for the leads of the electronic parts. Lead-free solders have a higher melting point requiring higher process temperatures (e.g., a 30°C typical difference for tin-silver-copper alloys), driving changes to materials for chip packages, for some printed circuit boards and components containing plastics. The higher temperature also precludes the use of components designed for lower temperatures. Interestingly, because these lead-free solders are less susceptible to high temperature failures, the automobile industry has used them to their advantage for years now, see the pros section.
Lead-free solders are significantly harder, which can increase the likelihood of cracks instead of plastic deformation, which is typical for lead-containing solders. Such cracks occur due to thermal or mechanical forces acting on components or the circuit board, the former being more common during manufacturing and the latter in the field.The editor of Conformity Magazine wonders if the transition to lead-free solder will not affect long-term reliability of electronic devices and systems, especially in applications more mission-critical than in consumer products, citing possible breaches due to other environmental factors like oxidation. This article refers to the Newark InOne "RoHS Legislation and Technical Manual", which cites these and other "lead-free" solder issues, such as:
Warping or delamination of printed circuit boards;
Damage to through-holes, ICs and components on circuit boards; and,
Added moisture sensitivity, all of which may compromise quality and reliability.

Effect on reliability
Admission of reliability problems is found in Annex, item #7, of the RoHS directive itself, granting servers exemption from regulation until 2010. It should be noted that these issues were raised when the directive was first implemented in 2003 and reliability effects were less known.
Another problem that lead-free solders face is the growth of tin whiskers. These thin strands of tin can grow and make contact with an adjacent trace, developing a short circuit. Research has also identified a particular failure mode for tin whiskers, where in high power components a short circuiting tin whisker is ionized into a plasma that is capable of conducting hundreds of amps of current, massively increasing the damaging effect of the short circuit. Tin whiskers have already been responsible for at least one failure at a nuclear power plant. Other documented failures include satellites in orbit, aircraft in flight, and implanted medical pacemakers. It should be noted that these failures pre-date RoHS and do not involve consumer electronics, and therefore would be exempt. To help mitigate potential problems, lead-free manufacturers are using a variety of approaches such as tin-zinc formulations that produce non-conducting whiskers. Fortunately, experience thus far suggests deployed instances of RoHS products are not failing due to whisker growth. Dr. Ronald Lasky of Dartmouth College reports: "RoHS has been in force for more than 15 months now, and ~$400B RoHS-compliant products have been produced. With all of these products in the field, no significant numbers of tin whisker-related failures have been reported." Whisker growth can occur slowly over time, is unpredictable, and not fully understood, so time may be the only true test of these efforts.
Reliability decay of low-lead materials may be economically desirable for some consumer product companies because it provides a mechanism to enforce planned obsolescence and replacement. Ironically, this is the opposite of the claimed intent of RoHS legislation.[citation needed]
Some countries have exempted medical and telecommunication infrastructure products from the legislation. However, this may be a moot point, as electronic component manufacturers convert their production lines to producing only lead-free parts, conventional parts with eutectic tin-lead solder will simply not be available, even for military, aerospace and industrial users. To the extent that only solder is involved, this is at least partially mitigated by many lead-free components' compatibility with lead-containing solder processes. Leadframe based components, such as QFPs, SOICs, and SOPs with gull wing leads, are generally compatible since the finish on the part leads contributes a small amount of material to the finished joint. However, components such as BGAs which come with lead-free solder balls and leadless parts are often not compatible with lead-containing processes.

Economic effect
There are no de minimus exemptions, e.g., for micro-businesses, meaning that some small businesses have closed down, citing the cost of compliance. This economic effect was anticipated and at least some attempts at mitigating the effect were made. Another form of economic effect is the cost of product failures attributed to RoHS compliance. For example, tin whiskers were responsible for a 5% failure rate in certain components of Swiss Swatch watches in 2006, reportedly triggering a $1 Billion recall. Swatch responded to this by applying for exemptions to RoHS compliance for two components. One of these exemptions was effectively approved, with the other still pending after an initial denial. For the denied part Swatch has stated to be using a replacement solder that is almost pure lead, and its application was for permission to switch to a solder with a lower lead content.

Tin phase transformation
In an article published in Advanced Packaging, November/December 2006, Glenn A. Rinne of Unitive Electronics, Inc. (an Amkor Company) describes the allotropic phase transformation of tin, also known as tin pest, which begins at temperatures below 13°C (about 55°F). Tin pest causes solder joints affected by it to crumble. The effect is difficult to predict and control, because the transformation is slow. Interestingly, the effect was already known more than 100 years ago, as it has at various times been cited as a factor in the failure of Napoleon's Russian campaign, and Robert Scott's South Pole expedition.

By: Jan Michael Masaganda