Lo, presto and waste dissapears!

Just close your eyes and picturise the amount of waste we humans are spewing out every moment. Take plastic bags for instance: 1 trillion bags are produced every year and 3.5 tonnes by weight are discarded every year! It takes around 1000 years for a bag to degrade! Obviously, every one of them we have made is still around!

E-waste is another growing class of waste. Around 50 million tones are discarded every year. This could go up by 500 percent in another decade, says the UNEP! Recycling is one way out but complete recycling is still a distant hope.

Hopefully, research is on to tackle this problem. A team of U.S. scientists at University of Illinios says it has developed a class of biodegradable electronics technology that could be utilized for a wide range of products — from consumer devices to medical implants — and that ultimately would dissolve completely, leaving no environmental impacts.

The technology has been used experimentally to make transistors, diodes, temperature sensors, and solar cells that degrade completely in even tiny amounts of water, the researchers say. The devices are encapsulated in silk, enabling manufacturers to alter the rate of dissolution based on the structure of the silk used. According to John Rogers, leader of the research team, the technology could be used for a myriad of electronic devices that end up in landfills; for environmental monitoring equipment, such as sensors used in oil spills; and for medical implants needed for short-term diagnostic or therapeutic functions.

That still leaves us with all the plastic…

The frozen warriors

Small rooftop wind generators are being increasingly installed in many cities in India. But the issue is that wind speeds are below required rates in most places. Surprisingly the subsidy given by MNRE places no criteria as to which zone the installations are permitted in. Geographically, experts say that hardly 10% area is suitable for wind machines as wind power is proportional to cube of velocity. A 1000 watt machine designed for 12 m/sec velocity generates less than 100 watt at half wind speed of 6m/sec and ceases to generate at 4 m/sec. They remain like battle showpieces perched on housetops!

What is the solution in such a scenario? Why can’t the state renewable development agencies offer consultancy solutions to households opting for such units? Instead of rushing to pitch in and go self-reliant in every which way, people need to be educated on what is the best locally available resource. Witness the recent scramble in Bangalore to segregate waste at source, and the resultant mandate on large apartment blocks left high and dry to do composting of wet waste independently.  The situation could have been avoided if citizens were prepared in advance. Should PV panels be placed on rooftops? What are the maintenance conditions? Do manufacturers bother to educate buyers? What the sensitive citizen needs today is not to be confronted with a wide array of possible solutions but a consultant giving wise choices. Like with everything else, one size does not fit all and each case presents a new possibility.

Not too far

Climate change is already contributing to the deaths of nearly 400,000 people a year and costing the world more than $1.2 trillion, wiping 1.6% annually from global GDP, according to a new study. By 2030, the researchers estimate, the cost of climate change and air pollution combined will rise to 3.2% of global GDP, with the world's least developed countries forecast to bear the brunt, suffering losses of up to 11% of their GDP.

The impacts are being felt most keenly in developing countries, according to the research, where damage to agricultural production from extreme weather linked to climate change is contributing to deaths from malnutrition, poverty and their associated diseases.

Air pollution caused by the use of fossil fuels is also separately contributing to the deaths of at least 4.5m people a year. The 331-page study, entitled Climate Vulnerability Monitor: A Guide to the Cold Calculus of A Hot Planet was carried out by the DARA group, a non-governmental organisation based in Europe, and the Climate Vulnerable Forum. It was written by more than 50 scientists, economists and policy experts, and commissioned by 20 governments.

Climate change is not necessarily a long-term problem. Scientists have been alarmed by the increasingly rapid melting of Arctic sea ice. Some research suggests that this melting could be linked to cold, dull and rainy summers in parts of Europe. In the US, this year's severe drought has raised food prices and in India the disruption to the monsoon has caused widespread damage to farmers. Yet, we fail to rise to the challenge.

UK renews hopes

According to a latest research conducted by alternative energy analysts at GlobalData, UK’s renewable energy installed capacity is expected to match the dominant thermal energy sector by 2025. Aggressive government policies and support are expected to be a key reason for a drastic shift in the UK’s energy mix by 2025.

The report determines that the renewable energy industry is the fastest-growing segment in the UK’s power sector, and is expected to climb significantly from 11,000 MW of installed capacity recorded last year.

The report predicted that, by 2025, cumulative installed capacity of renewable energy will reach up to 79,000 MW, which is just 2,000 MW less than the anticipated capacity of thermal power capacity at that time.

According to the report, the wind energy sector is expected to grow at the fastest pace — from 6,000 MW in 2011, to 53,000 MW in 2025. Solar photovoltaics is also expected to show strong growth — from just 1,000 MW in 2011, to 13,338 MW in 2025. Many hurdles there, but as starters that is good news.

Arctic snow too melting fast

A recent estimate from climate researchers suggested that the melting of Arctic sea ice could result in the warming equivalent of 20 years of CO2 emissions, due largely to the loss of huge swaths of the color white. White reflects light — including sunlight. More white means less absorbed heat. Now it seems not only sea ice but snow on land too is melting at record rate. A study by Canadian researchers finds that springtime snow is melting away even faster than Arctic ice. That also has profound implications for the Earth’s climate.

Springtime snowmelt matters a lot: It determines when spring runoff comes out of the mountain to fill our rivers. And Chris Derksen at Environment Canada in Toronto says snow also reflects sunlight back into space, helping to keep the Earth from heating up too fast.

“When you remove the snow cover form the land surface, much as when you remove the sea ice from the ocean, you take away a highly reflective, bright surface, and you expose the bare land or tundra underneath, and that absorbs more solar energy,” he says.

What’s worse is that the decline of springtime snow is happening faster than that of Arctic ice. The Environment Canada team calculated that snowmelt is declining at 18 percent per decade, compared to 11 percent for the ice cap. And what’s even worse is that the snowmelt is only the first layer of the problem. Beneath the snow is the permafrost, which is no longer as “perma.” Thawing permafrost, as we’ve mentioned before, releases methane into the atmosphere, contributing more to warming than the same amount of carbon dioxide.

Apocalypse in the making?

A tip from Rover!

The latest Rover on Mars may have some good news for energy hunters back home!

The Rover depends on a sandwich of semiconducting material that can turn heat into electricity. In this present case, the steady radioactive decay of plutonium 238 warms such thermoelectric material and turns roughly 4 percent of that heat into a steady flow of electrons. A similar radioisotope thermoelectric generator (RTG) on the moon's Sea of Tranquility is still working after decades, as are the RTGs in the two Voyager spacecraft launched 35 years ago.

While 4 percent of heat may seem too small for earthly needs, researchers have discovered a way to at least double the efficiency of such power generators. The most common core of new and old thermoelectric is a compound called lead telluride. When exposed to heat on only one side it induces an electric current as long as the temperature differential is maintained. The challenge has been to keep heat from transferring across the material without also interfering with its ability to conduct electricity.

By engineering the material from the atomic to the individual grain scale, the thermal conductivity of lead telluride can be impeded without affecting its electrical conductivity. The result is a material that can convert at least 8 percent of the heat into electricity—and could theoretically convert as much as 20 percent.

The researchers first melted the lead telluride and then froze it, creating nanoscale crystalline structures out of the atoms. These precisely oriented nanostructures scatter the medium wavelength vibrations, or phonons, that carry heat while allowing electrons to pass unobstructed. But longer wavelength phonons continue to pass through as well, because their wavelengths are longer than the size of the nanostructures. It was this hurdle that the engineering overcame.

Such thermoelectric devices might become practical in harvesting some of the exhaust heat from vehicles—such as marine tankers or trucks—and turning it into electricity. BMW and Ford are already testing similar thermoelectric material in cars. Or the devices could be used in high-heat metallurgical or glassmaking industries.  Scientists at the Massachusetts Institute of Technology have even used such thermoelectric materials to build a device to turn the sun's heat more directly into electricity, rather than employing the vast arrays of mirrors of a conventional solar-thermal power plant.

Now the problem is that lead and tellurium are toxic, but surely material engineering will find new nontoxic alternatives?

Small is productive

How will the world find the water to feed a growing population in an era of droughts and water shortages? Can a resource like water be managed best by governments alone? Or can involving local community help?

A growing number of water experts are saying that the solution lies in forgetting big government-run irrigations projects with their mega-dams, giant canals, and often corrupt and indolent management. Farmers across the poor world, they say, are solving their water problems far more effectively with cheap Chinese-made pumps and other low-tech and off-the-shelf equipment. Researchers are concluding that small is both beautiful and productive.

In India, small-time rural entrepreneurs travel the countryside on bikes or donkey carts, with pumps strapped on the back. They rent the pumps for a dollar an hour, so even the poorest farmers can get some water from a local river or underground water reserve. In Burkina Faso in West Africa, pump owners supply a complete service, keeping small vegetable gardens irrigated for $120 to $150 per growing season. Of course, pumps need a power source, usually either electricity or diesel. But in India, some farmers are using dung from their cows to generate biodiesel. One Gujarati practitioner told IWMI researchers that dung-powered pumping saved him $400 a year in fuel.

Simple innovations are becoming a major driver of economic growth, poverty reduction, and food security, says the report, Water for Wealth and Food Security, published by the International Water Management Institute (IWMI). But much of the revolution is happening out of sight of governments and international organizations. In Ghana, for instance, small private irrigation schemes cover 185,000 hectares — 25 times more land than public irrigation projects, yet the agriculture minister hadn’t heard of these!

The 2000 report of the World Commission on Dams, set up by the World Bank, found that a quarter of dam-fed irrigation schemes watered less than 35 percent of the land intended, cost over-runs were almost universal, and a quarter of the irrigated fields were waterlogged or poisoned by salt.

Much like forests which were thought to be best protected by governments but now successfully involving locals, can water too be managed locally?

Unlimited wind

Exactly how much energy we can feasibly pull from the wind has been something of a controversial question in recent years, with some studies suggesting that wind power has its limits. Simulations unveiled this week by scientists in Delaware and California, though, argue that if anything, economics and politics will hold wind development back, rather than geophysical limits.

Wind-power systems work by taking the kinetic energy of wind and turning it into mechanical energy in the turbine to create electrical energy. Laws of physics tell us that the total amount of energy can’t change, so at least a minor slowing of the wind is expected as it passes through the turbine. New research, published Sunday in Nature Climate Change, used a climate model to estimate that limit, both for turbines placed near Earth’s surface—as they are built now—and for high-altitude turbines, such as the kite-like tethered devices currently under development.

They found that the geophysical limit for Earth-based turbines is 428 terawatts or more but a whopping 1873 TW for high-altitude systems. The current global power demand? About 18 TW.  Another study of wind power’s geophysical limits, published in the journal Energy Policy in 2011, arrived at an upper limit of about 1 TW. But Mark Jacobson, a professor of civil and environmental engineering at Stanford, says that “the calculation of 1 TW was literally done with a back-of-the-envelope single-line equation” and didn’t take actual physical properties of turbines or the atmosphere into account.

All such calculations on the limit aside, we need to remember we do not even have enough cement to build so many turbines. To get to even 100 TW of installed capacity would require somewhere around 20 million very large turbines. A somewhat more realistic 4 million turbines could easily supply about half the world’s power.

The new studies also address a separate issue that arises with massive numbers of wind turbines: Can they actually cause climate change? The changes in kinetic energy that result from millions of spinning turbines do have an effect, but significant alterations to global temperature or weather patterns are only likely at “truly absurd extraction rates.”

White to grey

We have written about the loss of Arctic ice. Distant as it seems, the repercussions can be felt far away from the poles! In fact, the loss of Arctic ice is massively compounding the effects of greenhouse gas emissions, ice scientist Professor Peter Wadhams told BBC Newsnight. The absorption of heat by the melt water has the effect “equivalent of about 20 years of additional CO2 being added by man”.

Thirty years ago there was about eight million square kilometres of ice left in the Arctic in the summer, and by 2007 that had halved, it had gone down to about four million, and this year it has gone down below that. Yes, climate change.

However, the U.N. climate talks featuring delegates from 190 nations, that have been ongoing for the last week in Bangkok, Thailand, and which conclude today, have produced nothing much to write about!

Last December at the Durban COP talks, the world's nations agreed that they would sign a legally-binding pact to cut emissions and help developing nations adapt to climate change, from 2020. Part of this agreement included a promise to deepen existing promises to cut emissions by the end of the decade. At the summit, the U.N. released a report showing that several rich nations will not even meet their existing pledges to cut greenhouse gas emissions by the end of the decade, made at Copenhagen in 2009. These nations include Australia, Canada, Japan, Mexico, South Africa, South Korea and the US.

Not a single country has made a fresh commitment, and US negotiators stunned delegates by calling for a new treaty to be ‘flexible’ and ‘dynamic’ rather than legally binding, representing a complete U-turn on its previous position.

With the present level of commitments to reduce emissions, the world is still on for at least a 3°C temperature rise, which would have catastrophic repercussions.
India is experiencing its fourth drought in a dozen years, raising concerns about the reliability of the country’s primary source of fresh water, the monsoon rains that typically fall from June to October. Studies using 130 years of data show big changes in rainfall in recent decades, according to <http://bit.ly/Qgblr2>B. N. Goswami, director of the Indian Institute of Tropical Meteorology. Climate models suggest that while overall rainfall should increase in the coming decades, the region can expect longer dry spells and more intense downpours ­ forces that would seem to cancel each other out but in fact pose new threats. Heavy rains are normally short duration, and therefore the water runs off, while weak rains are important for recharging groundwater.

Off grid and interactive

Banning coal mining in thick forests is a wise decision for the future but what about today? With no substantial gas reserves or imports, what can India fall back on? The editorial in CSE this week talks about all this, and concludes:

‘We need to understand how to reduce losses in distribution… we also know that there are huge leakages—estimated at 25 per cent by the Central Electricity Authority. This needs to be fixed. For this, we need to look at generating energy locally so that distribution costs are brought down, transmission losses are curtailed and recovery from clients made easier. It is here we need to look at the massive opportunity provided by renewable energy, particularly solar. But before that we must understand that new energy sources like solar will work only if we figure out a new business model for generation and supply—and not look for solar to work within the leaking and non-remunerative grid system.

‘My colleagues at the Centre for Science and Environment have proposed off-grid but interactive systems for rural electrification. In this system, like the German roof-top energy revolution, government would provide feed-in tariff incentives for entrepreneurs to set up local solar energy systems. This energy would be fed through mini grids to users—poor and rich would pay costs. It is important to remember that solar energy costs are decreasing—the latest bids for projects put the price at Rs 7 per unit. This is still more than the price of coal- or gas- based power. But while costs of coal and gas will only go up, solar can and will come down. Energy supply could be decentralised because demand is also decentralised. There could be a revolution in the making. But only if we see the light in the tunnel.’

It makes eminent sense, but like anything revolutionary it requires a quantum shift in the way we do things. What do you think? Write in.

Trees and rains

A team from the University of Leeds and the NERC Centre for Ecology & Hydrology found that for the majority of Earth's tropical land surface, air passing over extensive forests produces at least twice as much rain as air passing over little vegetation. In some cases these forests increased rainfall thousands of kilometres away. Deforestation thus can have a significant effect on tropical rainfall.

By combining observational data with predictions of future deforestation, the researchers estimate that destruction of tropical forests would reduce rain across the Amazon basin by up to a fifth (21 per cent) in the dry season by 2050. The study is published in Nature.

Lead author Dr Dominick Spracklen from the School of Earth and Environment at the University of Leeds said: "We were surprised to find that this effect occurs strongly across more than half of the tropics. We found that the Amazon and Congo forests maintain rainfall over the periphery of the forest basins -- regions where large numbers of people live and rely on rainfall for their livelihoods."

Scientists have debated whether vegetation increases rainfall for hundreds of years. It is well established that plants put moisture back in the air through their leaves by a process known as evapotranspiration, but the quantity and geographical reach of rainfall generated by large forests has -- until now -- been unclear. While there is plenty of anecdotal evidence that forests significantly increase rainfall, until now there has been a lack of observational evidence.

The team used newly available NASA satellite observations of rainfall and vegetation, along with a model which predicts atmospheric wind flow patterns, to explore the impact of Earth's tropical forests.

The more we upset the ecological balance, the effects can be seen in weather extremes, whether it be drought or floods. It is time to stop and think before we continue on this relentless exploitation.