WK10: Part 3: UUranium and Nuclear Energy

Uranium and Nuclear Energy

Uranium is a heavy metal with the highest atomic weight among naturally occurring elements.
It is radioactive and found in small amounts in rocks, soils, and even the human body.
Uranium is a key energy resource because it can undergo nuclear fission.
- Nuclear fission involves the splitting of an atom, releasing neutrons that can split further atoms.
Two common isotopes of uranium:
- Uranium-238
- Uranium-235: Less abundant but possesses fissile properties, making it crucial for nuclear fission reactions.

Uranium provides a low-carbon energy source.
Nuclear reactions using uranium are considered significant in meeting climate change strategies.

Most common deposits are found in sandstones.
Deposits also occur along unconformities (time boundaries between rock layers of different ages).
Polymetallic iron oxide breccias, such as the Olympic Dam deposit, contain significant uranium amounts.

In 2020, globally reasonably assured resources (RAR) of uranium were estimated at approximately 800,003,000 tons.
Known resources amount to about 6,100,000 tons.
Australia holds the largest uranium resources globally, accounting for about 31\%.

Uranium is primarily used to power nuclear power plants.
These plants contribute about 10\% to the total global electricity mix and approximately 18\% in advanced economies.
Currently, around 450 operating nuclear power plants generate about 2,700 terawatt hours of electricity.

China and Russia show growth in nuclear energy capacity, adding about 11.2 gigawatts in recent years.
Some regions, like Germany, are shutting down nuclear reactors without replacement.

Known uranium reserves are estimated to last 90 years, based on the current production rate (10% of reserves per year).
If production doubles to 20% per year, reserves would last 45 years.
At 40% annual production, reserves would only last approximately 22 years.
Mineral exploration suggests potential for finding more deposits.
New technologies, such as modular nuclear reactors, enhance efficiency and energy output per fuel unit.

The supply and demand chart shows fluctuations in uranium production from the late 1970s to the late 2010s.
Factors influencing supply and demand include:
- Supply and Demand: Increased demand raises prices, while overproduction lowers them, potentially rendering some mines uneconomic.
- Government Policies: Decisions to expand or phase out nuclear energy significantly affect demand and price.
- Global Energy Trends: The choice between fossil fuels and alternative sources impacts the price.
- Cleaner Energy Push: Global efforts for cleaner energy can boost nuclear power and increase demand.
- Production Costs and Mine Closures: Closure of mines like Ranger in Australia can strain the global market and increase prices.
- Geopolitical Factors: Instability in regions like Russia (a 6% supplier to the global uranium market) can disrupt supply chains and influence prices.

Fukushima (2011): The Fukushima disaster significantly shifted public perception of nuclear energy.
- Safety concerns led to reactor shutdowns, markedly decreasing uranium production around February 2011.
- Public confidence in nuclear energy declined considerably.
Long-Term Contracts: Renegotiation of long-term contracts can influence prices.

Back-of-the-envelope calculations based on the Coalition's nuclear policy announcement:
- Assumption of seven nuclear sites with an average reactor producing 1,000 megawatts (1 gigawatt).
- Australian electricity demand in 2040 projected to be 36.5 gigawatts (International Energy Agency data).
- Seven reactors could cover just under 20\% of Australia's electricity requirements in 2040.
- Investment required: between 60 and 90 billion AUD, assuming no cost overruns.

High capital costs: between 60 and 90 billion AUD per reactor.
Safety concerns regarding reactors and waste management.
Australia lacks regulatory framework and expertise for building and managing nuclear reactors.