Nuclear cannibals

Nuclear energy production must increase by more than 10 percent each year from 2010 to 2050 to meet all future energy demands and replace fossil fuels, but this is an unsustainable prospect. According to a report published in Inderscience's International Journal of Nuclear Governance, Economy and Ecology such a large growth rate will require a major improvement in nuclear power efficiency otherwise each new power plant will simply cannibalize the energy produced by earlier nuclear power plants.

Physicist Joshua Pearce of Clarion University of Pennsylvania has attempted to balance the nuclear books and finds the bottom line simply does not add up. There are several problems that he says cannot be overcome if the nuclear power option is taken in preference to renewable energy sources.

For example, the energy input required from mining and processing uranium ore to its use in a power plant that costs huge amounts of energy to build and operate cannot be offset by power production in a high growth scenario. There are also growth limits set by the grade of uranium ore. "The limit of uranium ore grade to offset greenhouse gas emissions is significantly higher than the purely thermodynamic limit set by the energy payback time," he explains.

In addition, nuclear power produces a lot of heat as a byproduct and this directly heats the Earth. This is only a relatively small effect, but as energy consumption grows it must be taken into consideration when balancing the energy equation.

However, it is the whole-of-life cycle analysis that Pearce has investigated that shows nuclear power is far from the "emission-free panacea" claimed by many of its proponents. Each stage of the nuclear-fuel cycle including power plant construction, mining/milling uranium ores, fuel conversion, enrichment (or de-enrichment of nuclear weapons), fabrication, operation, decommissioning, and for short- and long-term waste disposal contribute to greenhouse gas emissions, he explains.

Nuclear may stack up against the rampant fossil-fuel combustion we see today, but only by a factor of 12. This means that if nuclear power were taken as the major option over the next forty years or so, we would be in no better a position in terms of emissions and reliance on a single major source of energy than we are today given the enormous growth nuclear required over that timescale.

Pearce's analysis is based on current practice in the United States with regard to the mining and enrichment of ore. He suggests that rather than abandoning nuclear power, efforts should be made to improve its efficiency considerably. First, we could start utilizing only the highest-concentration ores and switch to fuel enrichment based on gas centrifuge technology, which is much more energy-efficient than current gaseous diffusion methods.

Nuclear plants might be used as combined heat and power systems so the "waste" heat is used, rather than allowing them to vent huge quantities of heat to the environment at the end of the electricity generation cycle. Pearce also suggests that we could "down-blend" nuclear weapons stockpiles to produce nuclear power plant fuel.

Source: Inderscience Publishers

Related stories:

Toxic legacy: Scientists ponder task of labelling nuclear waste
How will "DANGER!" be written 5,000 years from now? How will it be written in 50,000 years? Finding an answer to these questions may not seem like a Code Red emergency to most people.
AP Interview: Ex-Intel head pushes electric cars
(AP) -- Former Intel Corp. Chairman Andy Grove has a knack for sensing when circumstances should force changes at a company or an industry - and how to respond.
Britain outlines wind farm expansion plans
Thousands of new wind turbines could be built across Britain by 2020 as part of multi-billion pound plans to switch to more sustainable energy sources, British Prime Minister Gordon Brown said Thursday.
At Toyota greenhouse, C02 emissions no villain
In a sprawling greenhouse with shiny silver ducts running through, stacks of cardboard boxes feature prints of a flower alongside the distinctive red Toyota logo.
Argonne's supercomputer named world’s fastest for open science, third overall
The U.S. Department of Energy's (DOE) Argonne National Laboratory's IBM Blue Gene/P high-performance computing system is now the fastest supercomputer in the world for open science, according to the semiannual Top500 List of the world's fastest computers.
Reducing demand can lower electric bills, lessen chance of blackouts
A 5-percent reduction in electricity use will lower the market price of electricity, cut consumers' bills and lessen strain on the grid when demand shoots up this summer, say energy experts in Penn State's College of Earth and Mineral Sciences.
Astronomers weigh the coldest brown dwarfs with astronomy's sharpest eyes
Astronomers have used ultrasharp images obtained with the Keck Telescope and Hubble Space Telescope to determine for the first time the masses of the coldest class of "failed stars," a.k.a. brown dwarfs. With masses as light as 3 percent the mass of the sun, these are the lowest mass free-floating objects ever weighed outside the solar system. The observations are a major step in testing the theoretical predictions of objects that cannot generate their own internal energy, both brown dwarfs and gas-giant planets. The new findings, which are being presented in a press conference today at the American Astronomical Society meeting in St. Louis, show that the predictions may have some problems.
Physicist Claims First Real Demonstration of Cold Fusion
To many people, cold fusion sounds too good to be true. The idea is that, by creating nuclear fusion at room temperature, researchers can generate a nearly unlimited source of power that uses water as fuel and produces almost zero waste. Essentially, cold fusion would make oil obsolete.

News discussion:

Technology news