March 24, 2006
Nuclear Vs Solar Energy, Which?
By Ita, Melford
Today, nuclear plants employ multiple safety systems which alone account for about a quarter of the capital costs. What about solar and wind energy for electricity generation?, asks Melford Ita.Main image: Solar energy is environment friendly; silent, requires no fuel and does not pollute
Inset: Germany leads the world in wind energy generation and applications
With growing concerns over the potential hazard of a nuclear accident, spent fuel management and the fortuitous release of radioactive materials, it is wise to debate the role of nuclear power in terms of future energy policies. In April last year, the British government said in its effort to meet the targets on climate change, it would put nuclear power back on the agenda.
Provided they meet costs and waste concerns, Britain's Conservative Party - the Tories - support the construction of new nuclear stations. The Liberal Democrats, however, oppose the idea. The Tory shadow environment secretary, Tim Yeo, argued that the problem of carbon emissions could not be tackled if existing nuclear power stations were not replaced. "Nuclear power can play a role in addressing this problem providing it is cost-effective and can satisfy concerns about waste disposal," he explained.
According to Norman Baker, the environment spokesperson of the British Liberal Democrats, turning to nuclear power to tackle climate change is "like jumping from the frying pan to the fire". "Nuclear power may not contribute to carbon emissions, but it generates tonnes of radioactive wastes costing billions to store and will pose a risk to humans for thousands of years after disposal," he added.
Concurring with Baker, Darren Johnson of the UK's Green Party said nuclear reactors had an operational life of between 30 and 40 years but created waste that lasted "thousands" of years. "It is barking mad to consider nuclear power as part of a sustainable energy policy," he opined.
In November 2005, Tony Blair, the British prime minister, said "nuclear power is of course a difficult and challenging issue, but that is like most strategies to decide and what we actually need is a serious open and democratic debate, not one conducted by protests or demonstrations to stop people from having their freedom to express their views". Blair's view is that Britain needs more power whilst warming the planet less. Currently, 14 nuclear power stations generate 20% of Britain's electricity, but by 2023 all but one are due to close.
Incidentally, Germany (which has a great deal more nuclear plants than Britain) is allegedly phasing out its power stations. Some believe that wind, wave, and solar power can fill the gap.
Nuclear power generation uses uranium - named after the planet Uranus - to produce electricity. When an extra neutron is added to the nucleus of a uranium atom, it splits releasing heat energy. During splitting, several neutrons are released; these collide with another nucleus, causing further fission of uranium atoms, which in turn lead to chain reactions. During fission, heat converts water to steam, which turns a turbine thus generating electricity.
Uranium was discovered in pitchblende a mineral - in 1789 by the German chemist, Martin Klaproth. Formed about 6.6 billion years ago in the super novae, uranium is a heavy, dense metal with an abundant source of concentrated energy; a tonne can produce as much electricity as 2,000 tonnes of coal.
Owing to its high density, uranium lends itself to applications in the keels of yachts, as counterweights for aircraft rudders and elevators, and for radiation shielding, just to mention a few. Common in the Earth's crust as tin, tungsten and molybdenum, uranium also occurs in most rocks at concentrations of two to four parts per million (ppm). It is equally available in seawater and can be reprocessed to make more fuel. During reprocessing, plutonium is given off as a by-product.
In 1979, at Three Mile Island in the US, a reactor was severely damaged. Although about half the reactor core melted, there were no reports of health and environmental impacts. The accident was attributed to mechanical failure and operator confusion - the ubiquitous human factor.
In 1986, Chernobyl's (Ukraine) reactor suffered a similar fate - destroyed by fire and explosion, which left in its wake dire consequences for humans and the environment.
According to Corin Millas, chief executive of the European Wind Energy Association (EWEA): "Wind energy is one of the most effective technologies ready for global deployment that can help tackle these problems."
Germany (16,629 MW), Spain (8,263 MW), the US (6,740 MW), Denmark (3,117 MW) and India (3,000 MW) have the highest total installed wind power capacity. Italy, the Netherlands, Japan and the UK are above or near the 1,000 MW mark.
"It is barking mad to consider nuclear power as part of a sustainable energy policy," says the British Green Party MP, Darren Johnson
In 2004, Europe dominated the global market, accounting for 72.4% of new wind installations, amounting to 5,774 MW. Asia had a 15.9% of installation share (1,269 MW), followed by North America (6.4%; 512 MW) and the Pacific Region (4.1%; 325 MW). Latin America, the Caribbean (49 MW) and Africa (47 MW) had a 0.6% market share respectively.
On 31 January 2006, the German daily, RuhrNachrichten, reported that there were 17,000 wind turbines spread across Germany. Depending on wind availability, a single turbine can generate 500 KW - providing electricity for 200 homes, the newspaper said. Furthermore, in one German town with a population of about 550,000 inhabitants, 10.3% of the electricity consumed was harnessed from renewable energy sources. Germany continues to maintain its global lead in wind energy generation and applications.
Another fertile but so far hugely neglected source of energy is solar (or Photovoltaic-PV) which converts sunlight directly into electricity. It is environment friendly; silent, requires no fuel and does not pollute. Sceptics have queried PV efficacy on overcast days, but as it turns out, batteries collect current from the solar modules - storing the incoming electric energy as chemical energy; commonly referred to as the charge. When required, this chemical energy can be released as electric energy, the discharge. Appreciably, no energy is lost but stored in the battery for later use - as the case on overcast days.
PV is tested and proven. But it is sad to note that though the African continent receives significant energy from the sun, PV is not commanding enough support through research, development and implementation. Considering Africa's current and future energy demands, decision-making paradigms so far seem to foster a bleak future underpinned by dependency on energy sources which, if not tenable, will ultimately be usurped by enormous power wielding cartels.
In Europe, PV electricity is nearly five times as expensive as conventional electricity but grid-connected PV is gaining cost and benefit advantages through integration of electricity generation modules into buildings and other designs. In Britain, the cost of providing PV power supply capable of meeting demand from a standard energy-efficient house is roughly 20,000. While the outlay may seem high, it is a reasonable proportion of the cost of building a house.
A quarter of Europe's natural gas comes from Russia - 80% of that flowing through pipelines crossing the Ukraine. In a recent dispute over prices, Russia disrupted gas supplies to Ukraine. Following the blockade this winter, gas supplies through Ukrainian pipelines to Europe plummeted. Gazprom, the Russian state monopoly, said sufficient gas was still being piped via Ukraine to supply other countries, and if they were not receiving their gas, Ukraine must be diverting it.
Ukraine denied Russia's claim but said it would divert gas if temperatures dropped below freezing. The dispute sent chills, threatening to place Central and Western European nations in a firm winter grip. For regional governments across Africa, this grim and most recent European experience should serve as a reminder.
Succinctly, nobody really wants a nuclear plant in his or her backyard. IfPV is to make significant contributions towards social, economic and environmental sustainability, governments, power companies, architects, financial institutions, local authorities, scientists and manufacturers must overcome inertia.
Green tariffs and a fair price to groups generating solar electricity should be explored. Moreover, adopting a centrally funded energy-efficiency programme with significant subsidies for renewables can go a long way in encouraging the citizenry to do more with less. The time to act is now!
Copyright International Communications Mar 2006