SAN FRANCISCO — We might be living through a new age of miracles. Last month, Los Angeles decided against adding lanes to a freeway, an unexpected move in a city that has mistakenly thought for years that more lanes mean fewer traffic jams.

Shortly before that, Germany’s highest court ruled that diesel cars could be banned from city centers to clean up the air. Mind you, Germany is the land where diesel technology was invented — and Volkswagen, the world’s largest automobile maker, invested heavily in pushing the cars before it was caught lying about their emissions. After the court ruling, Volkswagen sputtered that it was “unable to comprehend” the decision.

These events occurred nearly 6,000 miles apart, in different political contexts, but they are connected. Both the public and a few of our bolder political leaders are waking up to the reality that we simply cannot keep jamming more cars into our cities.

A century of experience has taught us the folly of it. Three pathologies emerge. First, every car becomes the enemy of every other. The car you hate most is the one that’s right in front of you not moving. As cars pile in, journey times and pollution rise.

Second, after a certain point, more cars make the city a less congenial place for strollers, bicyclists and people who take public transit to their destinations. The cars push out frolicking kids, quiet afternoons reading on a bench and sidewalk cafes. So we give up our public space, our neighbor-to-neighbor conversations and ultimately our personal mobility for the next car, and the next one.

And then there is the odd fact, counterintuitive as it is, that building more roads does not really cure congestion and can even make it worse. The problem, as experts realized starting in the 1930s, is that as soon as you build a highway or add lanes to a freeway, cars show up to fill the available capacity. The phenomenon is so well understood that it has a name: induced traffic demand.

Read more at NYTIMES

IN 1954 the New York Times reported on a breakthrough in solar photovoltaic (PV) technology that could lead to “the harnessing of the almost limitless energy of the sun”. American researchers had discovered that silicon transistors, the building blocks of computers, could also generate electricity when hit by sunlight.

The same year, however, Lewis Strauss, chairman of America’s Atomic Energy Commission, made a balderdash prediction that nuclear power would soon become “too cheap to meter”. In the atomic frenzy of the 1950s America unleashed vast R&D; support for nuclear energy. Almost at birth, the silicon solar cell was gazumped by a rival non-fossil technology. For decades it lay in nuclear’s shadow.

No longer. Several recent books have celebrated a solar renaissance, as the cost of electricity generated by silicon PV has become competitive with that from fossil fuels and cheaper than nuclear power. “Taming the Sun” is not one of them.

Instead Varun Sivaram of the Council on Foreign Relations, a think-tank, issues a timely warning that solar power could stagnate as abruptly as nuclear did as a share of global energy in the 1990s, with dire consequences for the planet. Unless, that is, there is a triple focus on improving technology, new financial structures to back it and more resilient energy systems.

The book is not gloomy. It lays out the history, promise and pitfalls of solar technology with an easy-going lack of wonkishness. But it offers a sobering message that may be as prescient—and as readable—as Robert Shiller’s “Irrational Exuberance” was before the dotcom and housing crises of the 2000s.

Mr Sivaram is a good guide to a sector that, for all the attention it gets, generates just 2% of the world’s electricity. He has worked on the front-line as a grunt in a silicon-wafer factory and a scientist at Oxford University, with a startup in Silicon Valley, and as an energy adviser to the mayor of Los Angeles. His father lost a fortune in the industry. He has studied with (and affectionately describes) some of the boffins devising the future of solar technology.

None of these anecdotes distracts from his central argument—that the silicon cell, a worthy workhorse of the solar revolution, can carry the burden only so far. He contends that improvements in a cell’s efficiency, ie, the extent to which it converts sunlight into energy, stopped driving costs down as far back as 2001.

Read more at: ECONOMIST.COM

defenda os corais"O repórter Ernesto Paglia e o cinegrafista Alan Mendes, do Fantástico, passaram oito dias a bordo do navio Esperanza, do Greenpeace, acompanhando as pesquisas sobre os Corais da Amazônia. Hoje vai ao ar a reportagem que eles fizeram! Por isso, vamos estar no Twitter durante a exibição dela contando os bastidores e tirando dúvidas. Estaremos utilizando a hashtag #DefendaOsCorais e convidando as pessoas a assinarem a petição (faltam só 50 mil assinaturas para 2 milhões).

Mas precisamos da força de vocês também! Queremos que mais pessoas vejam o quão importante é defender esse bioma único. Quanto mais pessoas assistindo, comentando nas redes sociais sobre a matéria, postando a hashtag e chamando outras para assinarem a petição, melhor. Fiquem livres para criar os textos que quiserem no Twitter, mas o que é importante MESMO: link pra petição e a hashtag #DefendaOsCorais! O link é esse:"