Akshat Rathi

An unlimited source of clean energy just got a little easier to attain

February 13, 2014 Akshat RathiLeave a comment

Researchers in the US have overcome a key barrier to making nuclear fusion reactors a reality. In results published in Nature, scientists have shown that they can now produce more energy from fusion reactions than they put into nuclear fuel for an experiment. The use of fusion as a source of energy remains a long way off, but the latest development is an important step towards that goal.

Nuclear fusion is the process that powers the sun and billions of other stars in the universe. If mastered, it could provide an unlimited source of clean energy because the raw materials are plentiful and the operation produces no carbon emissions.

During the fusion process, smaller atoms fuse into larger ones releasing huge amounts of energy. To achieve this on Earth, scientists have to create conditions similar to those at the centre of the sun, which involves creating very high pressures and temperatures.

There are two ways to achieve this: one uses lasers and is called inertial confinement fusion (ICF), another deploys magnets and is called magnetic confinement fusion (MCF). Omar Hurricane and colleagues at the Lawrence Livermore National Laboratory opted for ICF with the help of 192 high-energy lasers at the National Ignition Facility in the US, which was designed specifically to boost fusion research.

A typical fusion reaction at the facility takes weeks of preparation. But the fusion reaction is completed in an instant (150 picoseconds, to be precise, which is less than a billionth of a second). In that moment, at the core of the reaction the pressure is 150 billion times atmospheric pressure. The density and temperature of the plasma created is nearly three times that at the centre of the sun.

The most critical part of the reaction, and one that had been a real concern for Hurricane’s team, is the shape of the fuel capsule. The capsule is made from a polymer and is about 2mm in diameter – about the size of a paper pinhead. On the inside it is coated with deuterium and tritium – isotopes of hydrogen – that are frozen to be in a solid state.

Hohlraum geometry with a capsule inside. Dr. Eddie Dewald/LLNL

This capsule is placed inside a gold cylinder, where the 192 lasers are fired. The lasers hit the gold container which emit X-rays, which heat the pellet and make it implode instantly, causing a fusion reaction. According to Debbie Callahan, a co-author of the study: “When the lasers are fired, the capsule is compressed 35 times. That is like compressing a basketball to the size of a pea.”

The compression produces immense pressure and temperature leading to a fusion reaction. Problems with the process were overcome last September, when, for the first time, Hurricane was able to produce more energy output from a fusion reaction than the fuel put into it. Since then he has been able to repeat the experiment.

Hurricane’s current output, although more than the hydrogen fuel put into the reaction, is still 100 times less than the total energy put into the system, most of which is in the form of lasers. Yet, this is a big achievement because reaching ignition just became easier.

Hurricane hasn’t yet reached the stated goal of the NIF that is to achieve “ignition”, where nuclear fusion generates as much energy as the lasers supply. At that point it would be possible to make a sustainable power plant based on the technology.

Scientists have been trying to tame fusion power for more than 50 years, but with little success. Although the National Ignition Facility, a US$3.5-billion operation, was built for classified government research, half of its laser time was devoted to fusion with an aim to accelerate research.

Zulfikar Najmudin, a plasma physicist at Imperial College London said: “These results will come as a huge relief to scientists at NIF, who were very sure they could have achieved this a few years ago.”

With laser-mediated ICF showing positive results, the obvious question is how does it compare with magnet-mediated fusion? According to Stephen Cowley, director of Culham Centre for Fusion Energy in Oxfordshire, “The different measures of success make it hard to compare NIF’s results with those of ‘magnetic confinement’ fusion devices.”

Culham works with magnetic confinement where, in 1997, the facility generated 16MW of power for 24MW put into the device. “We have waited 60 years to get close to controlled fusion. We are now close in both magnetic and inertial. The engineering milestone is when the whole plant produces more energy than it consumes,” Cowley said.

That may happen at the fusion reactor ITER, under construction in France, which is expected to be the first power plant that produces more energy than it consumes to sustain a fusion reaction.

First published on The Conversation. Image credit: LLNL.

If India’s future lies in its cities where women hardly work, we must all worry

February 13, 2014February 12, 2014 Akshat RathiLeave a comment

Nearly 400m people live in cities in India and during the next 40 years that number will more than double. Not only is the proportion of India’s total female population that is economically active among the lowest in the world, but urban areas do even worse. New analysis of data from the 2011 census shows only half as many urban women work as their rural counterparts.

Few states – including Iran, Pakistan and Saudi Arabia – do worse than India when it comes to women’s participation in the workforce. Others such as Somalia, Bahrain and Malaysia do much better. Among the BRICS (Brazil, Russia, India, China and South Africa) which are comparable emerging economies, India has the lowest female participation rate, with only 29% of women over the age of 15 working. As the chart below shows, even among the MINT countries – Mexico, Nigeria, Indonesia and Turkey – only Turkey has the same participation rate as India.

In mainly agricultural economies, urban women often find less work than rural ones. Half the working population in India is employed by the agricultural sector. But agriculture’s contribution to Indian economy has been steadily falling and is now less than half that of the services industry. This should have corresponded with rapid growth in numbers of working women in cities, but that hasn’t happened.

Economists have tried to understand this discrepancy. Some cite the problem to be India’s unemployment rate among the young, who make more than half of the population. But such joblessness should affect both men and women, and it also doesn’t explain the long-term trend of low women’s workforce participation rates. Others believe that younger people in cities are staying in education for longer. While that certainly contributes to the overall picture, it cannot explain the large difference between urban and rural figures.

Some discrepancy may arise because many women are involved in home-based work and are part of the informal sector, where their contribution tends to be under-reported. “Better enumeration will help, but measurement is not the only reason participation rates are so low in India, especially in urban areas,” Sher Verick, a senior fellow at the International Labour Organisation, said.

Patriarchy rules

According to Verick, the two main factors keeping women at home are social customs and very low education levels among women.

Breaking such customs is hard. Preet Rustagi, joint director of Institute for Human Development in Delhi, said: “To a certain extent, men control women’s lives. And women have internalised this as the norm. In such situations, the little work they do is the result of compulsion, such as when the household income is not enough, rather than choice.”

The power of social norms may be partially explained based on data from the city of Leicester in the UK, where one in four city-dwellers is of Indian background. According to a 2010 report by Sheffield Hallam University: “Economic activity rates among Indian women in Leicester are nine percentage points lower than for Indian women nationally.” In a large enough group of Indians, those social norms are more strongly held than when Indians are widely dispersed in the rest of the UK.

Although education levels have improved in recent decades, not as many educated women have found work.

“In India, there is a U-shaped relationship between education and participation of women in the workforce,” Verick said. “Illiterates participate more out of necessity. Women with a middle-level education (below graduate) have different aspirations and can afford to remain out of the workforce. Only better educated women have been ‘pulled’ into the labour force in response to better paid opportunities.”

Rustagi said a skills shortage among women is also to blame. “There is a large divide between what they can do and what jobs are on offer.” For instance, the lowest worker sex ratio is seen in construction, manufacturing and the retail trade, which are booming in cities.

The safety of women is also a concern in Indian cities, as was highlighted after the 2012 Delhi gang rape case. Better governance and improved policing ought to help, but urban India’s gender imbalance is a deeper cause for worry. The national average is 940 females per 1,000 males, but that drops to 912 for cities with a population larger than 1m. The imbalance is greater still in India’s biggest cities, with Delhi at 867 females per 1,000 males and Mumbai at 861.

The discrepancy in these figures may be partly explained by the mass migration of workers, mainly men, from rural to urban areas, according to Varsha Joshi, director of India’s census operations. But the drop is large enough that further investigation is needed to spot other reasons.

Empty promises

There are some positive signs. According to India’s National Sample Survey, the proportion of working women in urban areas has increased from 11.9% in 2001 to 15.4% in 2011. Rustagi said: “One of the fastest-growing sectors for urban working women has been domestic work. About 1.5m urban women were added to that sector in the last decade, which is more than one in ten jobs created for women in that time.”

But the areas that have shown the most significant growth, such as domestic work, tend to fall into the category of “informal” work – and under India’s labour laws, these workers have few workplace rights. This makes it harder for women to have sustainable jobs, let alone a career.

Indians go to the polls in April and, partly as a result of the focus of women’s issues, most parties have adopted promises about women’s empowerment as part of their campaigns, but none have spelt these promises out in any detail.

First published on The Conversation. Image credit: trinitycarefoundation

If GDP confuses you, here’s some much-needed clarity

February 9, 2014 Akshat RathiLeave a comment

Although it wasn’t created to measure progress, a country’s gross domestic product (GDP) quickly became the single measure that defined progress. Economist Diane Coyle has written a nice essay in Aeon magazine that explains GDP and its limitations, while putting it in historical context. Here are some highlights:

GDP is the sum in a given time period of everything produced in the economy with a monetary value, which should add up to the same figure as the incomes earned by every person and company, and the same as the total spent by everyone. In practice, these separate sides of the accounts are rarely equal because of the difficulty of getting all that data.
GDP was first developed in 1934, and it soon became the main tool for measuring a country’s economy.
Most people complain about GDP because it doesn’t measure non-monetary costs, which include environmental damage and social welfare. That is why a national disaster (or war) spurs faster GDP growth, but the loss of life and assets will not be included.
GDP is meant to measure market activities and, by definition, housework is not in the market; but there’s no market price for government activities either, and they are included.
While changes made to it later introduced hedonistic factors to include innovation, the list of products are severely limited.
Initially GDP didn’t count financial trading, but now it does. This leads to situations where, for instance, the biggest contribution from the financial sector to the UK economy occurred in the final quarter of 2008, which is when the financial crisis started.
GDP served as a decent measure when economic activity and social welfare went hand in hand, but now the gap between the two is widening.

In the end Coyle suggests that GDP is a flawed but useful number. That is why it must not be scrapped or changed. Instead newer measures for uncounted things need to be given more importance such as OECD’s Better Life Index.