Contemporary life has come to depend critically on availability of energy. For many purposes the source of energy is substitutable - thus, for example, power from oil, gas, coal, hydroelectric stations, nuclear fusion or wind turbines is equally suitable for meeting the needs of households. However, for many other contemporary uses, particular sources of power are required. Typically, petrol derived from oil is required for locomotion. So for cars, aircraft etc it is essential to have access to oil.
There are also additional dimensions which need to be considered for many sources of energy. Generation of Nuclear power, for example, requires agonising consideration of safety issues and the difficulty of disposing off radioactive waste. These make it both dangerous and economically unviable. Use of fossil fuels - oil, gas, and coal - lead to carbon dioxide emissions and climate change via the greenhouse effect. Burning forests to generate power leads to massive deforestation and environmental catastrophe. Siting hydroelectric power stations without paying heed to the ecosystem of the total water resource can also have adverse environmental impact.
When it comes to utilisation of energy a further complication emerges. There is a mismatch between users and owners of many of the energy reserves. Thus, countries with major reserves of oil, for example, are not the biggest users. The largest oil reserves are in Saudi Arabia, Iraq and Central Asia. The biggest users are the United States, Europe, Japan and increasingly India and China. The largest gas reserves are in Iran, Central Asia, Russia and Qatar. The biggest users are likely to be Europe and India.
Given the critical role that oil plays in industrial economies, countries like the USA, have tried to make plentiful supplies of cheap oil a matter of national security. Many of the geopolitical priorities and strategies of the USA can only be understood in this light. Many of the political and military interventions of the USA are also explicable if the overriding importance to access to cheap oil for the country is kept in mind. On the other hand supplies of cheap oil may not be in the interest of countries which own the resources. They may want to preserve resources and only sell enough at reasonable prices over a longer time frame. The scene is then set for power play and manipulation(s) by dominant powers to forcibly extract cheap and plentiful supplies of oil.
An examination of energy resources thus needs to be supplemented by economic, environmental and political considerations which make it one of the most potent sources of conflict in today's world.