Ugo Bardi's Contributions

Renewable energy, by definition, is inexhaustible or, at least, it can tap the sun's energy for times that can be considered infinite from our viewpoint. However, renewable energy doesn't live of sun alone. It needs metals, semiconductors, ceramics and more.

Do you remember the old Soviet Union? Dubbed as "The Evil Empire" by Ronald Reagan in 1983, it disappeared in a puff of smoke in 1991, crushed under a mountain of debts. The origins of the financial collapse of the Soviet Union are rather well known: it was related to the fall of the oil prices which, in 1985...

There is a question that has been nagging me for years: why do we keep in our pockets both paper money (banknotes or bills) and metallic coins? It wouldn't be difficult to write higher numbers on coins just a little bit larger than the ones we use today.

We live in a world where scientific evidence is trashed by ideological opinion, where people who learn from experience are accused of being flip-floppers, where changing one's mind on the basis of new data is seen as admitting one's lack of moral fiber. The debate on peak oil is no exception...

Yesterday, Mr. Angelino Alfano, leader of the "People of Freedom" (PdL) party, publicly presented a plan aimed at saving Italy from economic collapse. When he spoke, I was driving along the highway and by chance my radio was tuned on a channel that aired the presentation.

Last week, at a public meeting, I was asked several times if this famed "peak oil" has arrived or not. People who have heard of peak oil seem to be becoming impatient, but I am afraid we'll have to wait a little longer. Peak oil is not here yet, at least if we intend it as a significant decline in the production of combustible liquids.

Downcycling means that the material you obtain from recycling is not of the same quality as the one you started from. In this case, an old car, the problem is that the wreck doesn't just contain iron and carbon, which are the elements you start with when you make steel.

The return of interest in the original "Limits to Growth" study, conducted in 1972, seems to be literally exploding. On March 16, 2012, the Smithsonian magazine published a comment, citing Turner's work. The Smithsonian piece has been taken up on April 4 by Eric Pfeiffer on Yahoo news, which seems to be the first appearance of the study in mainstream news in the 21st century.

During the past few years, the financial system gave to the world a clear signal when the prices of all natural commodities spiked up to levels never seen before. If prices are high, then there is a supply problem.

Peak oil is behind us. That much seems to be clear from what was said at the 5th meeting of the Italian section of the Association for the study of peak oil (ASPO) held on Oct 28 in Florence, Italy.

In 1972, "The Limits to Growth" study arrived in a world that had known more than two decades of unabated growth after the end of the Second World War. It was a time of optimism and faith in technological progress that, perhaps, had never been so strong in the history of humankind.

Sometimes I wonder how it was that Cassandra, the Trojan prophetess, had so much trouble in convincing her fellow Trojan citizen that it was not such a good idea to demolish the city walls to let in that big, wooden horse.

Don't you stumble, sometimes, into something that seems to make a lot of sense but you can't say exactly why? For a long time, I had in mind the idea that when things start going bad, they tend to go bad fast. We might call this tendency the "Seneca effect" or the "Seneca cliff," from Lucius Anneaus Seneca who wrote that "increases are of sluggish growth, but the way to ruin is rapid."

We could modify the system taking into account many more effects – recycling waste for instance, but let me not go into that. Let's see, instead, is how the model describes Hubbert's curve which is the flow rate from the resources stock to the economy stock.

You may remember from your studies that entropy is related to disorder. In some senses, it is true, but it is a definition that creates a lot of confusion. Think of entropy as heat dissipation. Then, everything that happens in the world is the result of some heat being dissipated – entropy tends to grow.

For the past century or so, the biological origin of oil seemed to be the accepted norm. However, there remained a small group of critics who pushed the idea that, instead, oil is generated from inorganic matter within the earth's mantle. The question might have remained within the limits of a specialized debate among geologists, as it has been until not long ago. However, the recent supply problems have pushed crude oil to the center stage of international news.

A silver mask that had belonged to a Roman cavalryman of imperial times. It was found on the site of the battle of Teutoburg, fought in September 9 a.d. This year marks the 2000th anniversary of the battle that led to the annihilation of three Roman legions and changed forever the history of Europe. It was a tremendous shock for the Romans, who saw their mighty army destroyed by uncivilized barbarians. It was not yet the peak of the Roman Empire, but it was a first hint that something was deeply wrong with it.