The Guardian 13 July, 2005

The solar energy mystery

Peter Mac

The world is facing catastrophic changes in weather and natural systems. Fluorocarbons emitted from industrial equipment have eroded the atmospheric ozone layer that protects us from the sun's violent radiation. Carbon dioxide (CO2) emitted by industry and vehicles is boosting the amount of atmospheric solar radiation energy, leading to global warming, which threatens to raise sea levels and flood coastal areas. The CO2 particles also lead to "global dimming" which diminishes natural evaporation and increases the world-wide incidence of drought.


The means of dealing with this crisis, as proposed by Australian political leaders, are highly disturbing because of their very limited scope.

In many countries fluorocarbons used in industrial chemistry are gradually being replaced, for example in refrigeration cooling systems. However, reduction in CO2 levels is more problematical. It requires lowering the CO2 emission rate, for example by exhaust filtering systems or by using fuel with lower emission rates, but preferably by changing to energy sources that minimise CO2 production.

Among the worst CO2 emitters are coal-fired electricity power stations, and their replacement is currently the subject of great discussion in Australia. Prime Minister Howard has raised the possibility of changing to nuclear fission(*) power generation, and NSW Premier Carr has recommended a national discussion on this possibility.

Both politicians are cautious in raising this issue, in view of the catastrophic 1986 explosion of the Ukrainian Chernobyl reactor, and the earlier near melt-down of New York's Three-Mile Island nuclear plant. Nuclear fission doesn't produce CO2, but it has potential for terrible accidents and its radioactive waste remains highly toxic for hundreds of thousands of years.

The European Union has decided to build the world's first nuclear fusion reactor in France. If successful, this technology would deliver vast amounts of energy while producing little radioactive waste. However, there are enormous scientific and technical barriers to its industrial implementation. Ironically, the project will cost billions of dollars to reproduce the energy-making system of the sun, while Australia receives immeasurably more solar radiation than it could ever utilise for its own energy use.

Non-nuclear options

The nuclear option is only one of several alternatives to coal-fired power production. Holland currently derives almost 40 percent of its power from wind stations. In Australia, wind-power stations have been installed in some country locations, and a tiny station generating power from ocean waves has been proposed for construction off the Sydney coastline. Some people have installed domestic solar power-­generating panels in their homes.

These alternative energy sources have only been utilised here on a very small scale. The NSW government has largely ignored them, and has recently announced that it intends to construct a number of gas-fired power stations.

A federal Liberal politician, and former CSIRO scientist, has spoken favourably of the nuclear option. He dismissed the idea of wind power stations being used to generate Australia's power needs, stating that they would require huge areas of land, and would be likely to cost $180 billion to build.

It is not clear whether this figure has been arrived at by thorough and comprehensive scientific study. However, it's the first estimate given publicly for any means of replacing existing power stations. Despite the environmental crisis, there has been no major scientific, comprehensive and independent cost-­benefit analysis of alternative means of producing the nation's energy.

One ABC commentator has estimated we would need 35 nuclear power stations, and another that a "reasonably sized" nuclear station would cost $2 billion to build. Assuming these figures are correct, the construction cost for the nuclear option comes to approximately $70 billion.

If you factor in the unknown (but undoubtedly huge) extra costs of purchasing nuclear fuel, cooling the station's excess heat, and dealing with the waste products, the wind option costs don't look so bad. And in terms of health and safety and protecting the environment, wind power is way out in front.

Solar power

There's one potential source for power generation that is almost completely dismissed by most Australian politicians — solar power. This is astonishing, given that we live in a vast "wide brown land", which receives huge levels of solar radiation and will receive even more under the impact of global warming.

As is the case for wind and wave power systems, solar power generation has little or no adverse environmental impact. The collection of solar energy also requires no moving parts, thereby minimising plant maintenance costs. Moreover, domestic solar systems have the potential to generate surplus power, which can then be fed back into the public power grid.

Proposals for large-scale solar power stations are usually dismissed by our politicians on technical grounds, such as the need for massive amounts of solar collector panels, and batteries of huge storage capacity for periods when the sun isn't shining.

But this seems a pretty thin argument. All generating systems require some form of battery storage, for variations in demand. Moreover, solar radiation is at its strongest when the load on power systems is greatest, i.e. during periods of strong sunlight, when the use of air conditioning systems is maximised. Australia also has ample space for building power stations with huge areas of solar collectors.

Moreover, if domestic solar power systems were installed far more widely, it seems entirely possible that the need for power stations would be greatly minimised.

The current cost of providing a domestic solar system to meet the needs of the average family is about $20,000. At that rate, the assumed figure of $70 billion for nuclear power stations would provide domestic solar systems for some 3.5 million homes! That is pretty good, considering that our total population is only 20 million people.

Efficiencies

There are a number of other factors that would make the use of solar power even more feasible. Firstly, large-scale production of domestic solar systems, combined with government control to prevent price hikes from increased demand, would offer economies of scale and therefore considerable reductions in the cost of each system.

Secondly, the use of electrical energy directly where it is collected, as in domestic solar systems, offers very large reductions in the total amount of power required, compared with distribution from power stations. The loss of energy over the longest routes from a power station to the user point can reach 50 percent.

Thirdly, Australia has the potential to be a world leader in developing solar technology. One current research project, which utilises a process similar to the photosynthesis of plants, promises to vastly improve the efficiency of solar energy collection.

Fourthly, a mass domestic solar installation program could begin virtually immediately. In comparison, construction of a nuclear power plant would take years to accomplish. And time is crucial in the global warming race. We should be cutting CO2 immediately.

Fifthly, like wind and wave power, the source of solar energy is renewable, whereas coal, natural gas and uranium are all non-­renewable. Anti-nuclear campaigner Dr Helen Caldicott has estimated that if (hypothetically) the world tomorrow started to derive all its energy from nuclear fission power plants, the known stocks of uranium would be used up in ten years.

There are, of course, limitations to solar technology. Installation of solar panels would not be practical in many buildings because of their sites, form or orientation. However, extra panels to suitable buildings could provide surplus electricity which would be returned to the grid, thus lessening the need for major power stations.

If the number of panels was maximised, electricity generated "on site" could well become the predominant mode of power generation, with power stations supplying only supplementary power, with emergency back-up generating potential.

Given all this, solar power certainly seems economically feasible, and power systems based on wind or solar energy have a huge amount to offer in this period of environmental crisis. So why have our politicians so repeatedly given them, especially solar, the cold-shoulder?

The answer is that power station energy sources favoured or used by current Australian governments are gas, uranium and coal. All these fuels are privately owned, and their sale to governments reaps massive profits. On the other hand, wind and solar radiation come free-of-cost. That's very good news for the public, but extremely bad news for those who own or invest in fuel corporations.

And we all know that our governments are keen to stay on good terms with them.

(*)Nuclear fission: heavy atoms are split, creating energy and radioactive material.
In fusion the energy is created by reactions between light atoms that collide under considerable force and usually at extremely high temperature.


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