7.2 Energy Sources: Uses and Management

Energy security means a country's access to affordable and reliable sources of energy, at a scale sufficient to meet its needs without sudden disruption. It has three distinct, improvable components. Efficiency measures reduce how much energy a country needs in the first place, which shrinks its exposure even if supply is later disrupted. Decreasing reliance on imported energy supplies, by developing domestic sources, reduces vulnerability to a foreign supplier's decisions, whether commercial, political, or driven by conflict. Diversification, spreading energy supply across multiple sources and, where imports are unavoidable, multiple suppliers and routes, means that a single disruption cannot take out the whole system at once. The 2022 European gas crisis referenced in this subtopic's hook is the clearest recent illustration: countries with a diversified mix, including large nuclear or renewable shares, weathered the shock far better than countries that had let one imported fuel dominate their supply.

The global economy still mostly depends on finite reserves of fossil fuels, including coal, oil and natural gas. Exactly when these reserves are finally depleted is not a fixed date: it depends on several interacting factors. The rate of consumption matters directly, since faster use shortens the timeline. The discovery of new deposits can extend it, as previously unknown or previously uneconomical reserves become viable to extract. Developments in extraction technology, such as hydraulic fracturing opening up shale gas and oil that was once inaccessible, have historically pushed depletion timelines further out than earlier predictions assumed. Finally, increased use of renewables or nuclear power reduces demand for fossil fuels directly, which can slow depletion even without any change in the physical size of the remaining reserves. Because all four factors interact and none is fixed, published depletion timelines should always be read as estimates under stated assumptions, not firm deadlines.

Nuclear power is a non-renewable, low-carbon means of electricity production. Most nuclear power stations generate electricity through fission reactions of uranium or plutonium: splitting heavy atomic nuclei releases enormous amounts of energy, which is used to heat water into steam that drives a turbine, the same basic principle as a fossil fuel power station, but without direct combustion emissions.

The economics are unusual: construction costs are very high and construction itself can take a decade or more, but once a plant is built and operating, it produces low-cost, constant, low-carbon energy for decades, often 40 to 60 years, without depending on weather conditions the way wind or solar do. This combination of high upfront cost and low, steady running cost is central to why nuclear power divides opinion on economic grounds alone, before environmental or safety arguments even enter the discussion.

The disadvantages are also substantial. Mining uranium has negative environmental effects at the extraction site. Thermal pollution, heat discharged into nearby rivers or coastal water used for cooling, changes local water chemistry and can harm aquatic life. There is a real, if statistically low, risk of nuclear accidents, and the consequences of a severe accident can be catastrophic and long-lasting, as seen at Chernobyl (1986) and Fukushima (2011). Finally, radioactive waste is produced at every stage of the fuel cycle and must be stored indefinitely in containers engineered to shield the environment from radiation, a still-unresolved long-term challenge, since some waste remains hazardous for thousands of years.

Battery storage is required at a large scale to meet global carbon-emission reduction targets, since it is what makes intermittent renewable electricity usable around the clock. But batteries are not an environmentally free solution: producing them requires mining, transporting, processing and construction, all of which produce their own emissions and pollution, and can cause sociopolitical tension.

The main elements required for effective batteries are lithium, cobalt and various rare earth elements. Mining and processing these creates toxins and pollution both on land and in the ocean, and mine tailings dam failures, catastrophic releases of toxic mining waste, have occurred at real sites. The geography of supply compounds the problem: these elements are not evenly distributed. Roughly 70-75% of the world's cobalt is mined in the Democratic Republic of Congo alone, though it is mostly refined elsewhere, principally China, meaning the DRC captures relatively little of the value from a resource critical to the global battery industry. Lithium is less concentrated but still narrow: Australia and Chile together supply close to 75% of the world's lithium. Because this small handful of countries controls resources that the entire world now urgently needs, unintended consequences follow: price volatility, supply chain fragility, and geopolitical conflict over access and control.