RENEWABLE ENERGY

An insight into the progress in renewable energy research

A The race is on for the ultimate goal of renewable energy: electricity production at prices that are competitive with coal-fired power stations, but without coal’s pollution. Some new technologies are aiming to be the first to push coal from its position as Australia’s chief source of electricity.

B At the moment the front-runner in renewable energy is wind technology. According to Peter Bergin of Australian Hydro, one of Australia’s leading wind energy companies, there have been no dramatic changes in windmill design for many years, but the cumulative effects of numerous small improvements have had a major impact on cost. ‘We’re reaping the benefits of 30 years of research in Europe, without have to make the same mistakes that they did,’ Mr. Bergin says.

C Electricity can be produced from coal at around 4 cents per kilowatt-hour, but only if the environmental costs are ignored. ‘Australia has the second cheapest electricity in the world, and this makes it difficult for renewable to compete,’ says Richard Hunter of the Australian Ecogeneration Association (AEA). Nevertheless, the AEA reports: ‘The production cost of a kilowatt-hour of wind power is one-fifth of what it was 20 years ago,’ or around 7 cents per kilowatt-hour.

D Australian Hydro has dozens of wind monitoring stations across Australia as part of its aim to become Australia’s pre-eminent renewable energy company. Despite all these developments, wind power remains one of the few forms of alternative energy where Australia is nowhere near the global cutting edge, mostly just replicating European designs.

E While wind may currently lead the way, some consider a number of technologies under development have more potential. In several cases, Australia is at the forefront of global research in the area. Some of them are very site-specific, ensuring that they may never become dominant market players. On the other hand, these newer developments are capable of providing more reliable power, avoiding the major criticism of windmills – the need for back-up on a calm day.

F One such development uses hot, dry rocks. Deep beneath South Australia, radiation from elements contained in granite heats the rocks. Layers of insulating sedimentation raise the temperatures in some location to 250° centigrade. An Australian firm, Geoenergy, is proposing to pump water 3.5 kilometres into the earth, where it will travel through tiny fissures in the granite, heating up as it goes until it escapes as steam through another drilled hole.

G No greenhouse gases are produced, but the system needs some additional features if it is to be environmentally friendly. Dr. Prue Chopra, a geophysicist at the Australian National University and one of the founders of Geoenergy, note that the steam will bring with it radon gas, along through a heat exchanger and then sent back underground for another cycle. Technically speaking, hot dry rocks are not a renewable source of energy. However, the Australian source is so large it could supply the entire country’s needs for thousands of years at current rates of consumption.

H Two other proposals for very different ways to harness sun and wind energy have surfaced recently. Progress continues with Australian company EnviroPower’s plans for Australia’s first solar chimney near Mildura, in Victoria. Under this scheme, a tall tower will draw hot air from a greenhouse built to cover the surrounding 5 km². As the air rises, it will drive a turbine* to produce electricity. The solar tower combines three very old technologies – the chimney, the turbine and the greenhouse – to produce something quite new. It is this reliance on proven engineering principles that led Enviropower’s CEO, Richard Davies, to state: There is no doubt this technology will work, none at all.’

I This year, Enviropower recognized that the quality of sunlight in the Mildura district will require a substantially larger collecting area than was previously thought. However, spokesperson kay Firth says that a new location closer to Mildura will enable Enviropower to balance the increased costs with extra revenue. Besides saving in transmission costs, the new site ‘will mean increased revenue from tourism and use of power for telecommunications. We’ll also be able to use the outer 500 metres for agribusiness.’ Wind speeds closer to the tower will be too high for farming.

J Another Australian company, Wavetech, is achieving success with ways of harvesting the energy in waves. Wavetech’s invention uses a curved surface to push waves into a chamber, where the flowing water column pushes air back and forth through a turbine. Wavetech was created when Dr. Tim Devine offered the idea to the world leader in wave generator manufacturers, who rather surprisingly rejected it. Dr. Devine responded by establishing Wavetech and making a number of other improvements to generator design. Wavetech claims that, at appropriate sites, ‘the cost of electricity produced with our technology should be below 4 cents per kilowatt-hour.

K The diversity of forms of greenhouse – friendly energy under development in Australia is remarkable. However, support on a national level is disappointing. According to Richard Hunter of the AEA, ‘Australia has huge potential for wind, sun and wave technology. We should really be at the forefront, but the reality is we are a long way behind.’

INSIDE THE MIND OF A FAN: HOW WATCHING SPORT AFFECTS THE BRAIN

A At about the same time that the poet Homer invented the epic here, the ancient Greeks started a festival in which men competed in a single race, about 200 metres long. The winner received a branch of wild olives. The Greeks called this celebration the Olympics. Through the ancient sprint remains, today the Olympics are far more than that. Indeed, the Games seem to celebrate the dream of progress as embodied in the human form. That the Games are intoxicating to watch is beyond question. During the Athens Olympics in 2004, 3.4 billion people, half the world, watched them on television. Certainly, being a spectator is a thrilling experience: but why?

B In 1996, three Italian neuroscientists, Giacomo Rizzolatti, Leonardo Forgassi, and Vittorio Gallese, examined the premotor cortex of monkeys. The discovered that inside these primate brains there were groups of cells that ‘store vocabularies of motor actions’. Just as there are grammars of movement. These networks of cells are the bodily ‘sentences’ we use every da y, the ones our brain has chosen to retain and refine. Think, for example, about a golf swing. To those who have only watched the Master’s Tournament on TV, golfing seems easy. To the novice, however, the skill of casting a smooth arc with a lop-side metal stick is virtually impossible. This is because most novices swing with their consciousness, using an area of brain next to the premotor cortex. To the expert, on the other hand, a perfectly balanced stroke is second nature. For him, the motor action has become memorized, and the movements are embedded in the neurons of his premotor cortex. He hits the ball with the tranquility of his perfected autopilot.

C These neurons in the premotor cortex, besides explaining why certain athletes seem to possess almost unbelievable levels of skill, have an even more amazing characteristic, one that caused Rizzolatti, Fogassi,and Gallese to give them the lofty title ‘mirror neurons’. They note, the main functional characteristic of mirror neurons is that they become active both when the monkey performs a particular action (for example, grasping an object or holding it) and, astonishingly, when it sees another individual performing a similar action.’ Humans have an even more elaborate mirror neuron system. These peculiar cells mirror, inside the brain, the outside world: they enable us to internalize the actions of another. In order to be activated, though, these cells require what the scientists call ‘goal-orientated movements’. If we are staring at a photograph, a fixed image of a runner mid-stride, our mirror neurons are totally silent. They only fire when the runner is active: running, moving or sprinting.

D What these electrophysiological studies indicate is that when we watch a golfer or a runner in action, the mirror neurons in our own premotor cortex light up as if we were the ones competing. This phenomenon of neural mirror was first discovered in 1954, when two French physiologists, Gastaut and Berf, found that the brains of humans vibrate with two distinct wavelengt hs, alpha and mu. The mu system is involved in neural mirroring. It is active when your bodies are still, and disappears whenever we do something active, like playing a sport or changing the TV channel. The surprising fact is that the mu signal is also quiet when we watch someone else being active, as on TV, these results are the effect of mirror neurons.

E Rizzolatti, Fogassi, and Gallese call the idea for mirror neurons the ‘direct matching hypothesis’. They believe that we only understand the movement of sports stars when we ‘map the visual representation of the observed action onto our motor representation of the same action’. According to this theory, watching an Olympic athlete ‘causes the motor system of the observer to resonate. The “motor knowledge” of the observer is used to understand the observed action.’ But mirror neurons are more than just the neural basis for our attitude to sport. It turns out that watching a great golfer makes us better golfers, and watching a great sprinter actually makes us run faster. This ability to learn by watching is a crucial skill. From the acquisition of language as infants to learning facial expressions, mimesis (copying) is an essential part of being conscious. The best athletes are those with a premotor cortex capable of imagining the movements of victory, together with the physical properties to make those movements real.

F But how many of us regularly watch sports in order to be a better athlete? Rather, we watch sport for the feeling, the human drama. This feeling also derives from mirror neurons. By letting spectators share in the motions of victory, they also allow us to share in its feelings. This is because they are directly connected to the amygdale, one of the main brain regions involved in emotion. During the Olympics, the mirror neurons of whole nations will be electrically identical, their athletes causing spectators to feel, just for a second or two, the same thing. Watching sports brings people together. Most of us will never run a mile in under four minutes, or hit a home run. Our consolation comes in watching, when we gather around the TV, we all feel, just for a moment, what it is to do something perfectly.