The world relies on a variety of different sources of energy. In 2018 fossil fuels, like gas, oil and coal, were responsible for more than 81 percent energy consumed. Renewables, including solar power, wind, biomass and hydroelectricity, account for 14 percent. Nuclear energy is responsible for another five percent. Different countries utilize different energy sources to balance economic needs and environmental concerns.

Energy is present in nature in many forms, including sunlight and wind, waves, oceans and more. When harnessed, and transformed into more convenient forms of energy, such as heat or electricity, they are referred to as primary sources. These energy sources become non-renewable sources of energy when they are exhausted.

The environment is damaged due to a wide range of fossil fuels as well as some other energy sources that aren't renewable. For instance, oil mining can cause the destruction of our forests of the earth. Fracking (hydraulic fracturing) can result in water pollution and earthquakes. Carbon dioxide is released when coal is burned which causes global warming.

Fortunately, some of the most promising sources of energy are renewable and sustainable. Wind, solar, and hydropower can create, for instance, electricity without the need to dig up new sources.

Other sources of sustainable energy are emerging, such as tidal and wave power. To be used at a large-scale, these technologies need to have effective distribution networks. These need to be built using a source of non-renewable energy sources. Therefore, these sources aren't able to provide the bulk of our energy needs. But it's important keep in mind that costs for renewable energy equipment have decreased drastically over the last couple of years, and efficiency is growing quickly.