The world uses a variety of energy sources. In 2018 fossil fuels, like gas, oil and coal, were responsible for over 81 percent of the energy consumed. Renewables, such as solar power, wind power, hydroelectricity and biomass, account for 14 percent. Nuclear energy contributes another 5 percent. Different countries have different combinations of energy sources, while balancing the needs of the economy with environmental concerns.
Nature’s energy is available in a variety of forms like sun, wind waves and ocean. When harnessed and converted into more efficient forms of energy, like electricity or heat, these are known as primary sources. These sources are non-renewable resources of energy once they have been exhausted.
Many fossil fuels, as well as some of the other energy sources visite site that are not renewable can be harmful to the environment. For instance, oil mining can devastate the forests of the earth. Fracking (hydraulic fracture) can cause water pollution and earthquakes. Carbon dioxide is released when coal is burnt, which contributes to global warming.
Fortunately some of the most promising energy sources are renewable and sustainable. Hydropower, solar energy and wind power, for instance, can generate electricity without the need to search for fresh supplies.
Other renewable energy sources are emerging, like the wave and tidal power. However, in order to be used on a massive scale they must have effective distribution networks. These need to be built which will require the use of non-renewable energy. Therefore, these sources are not yet sufficient to meet the majority of our energy needs. It is important to keep in mind that the cost of renewable energy equipment has decreased dramatically in recent times and the efficiency of these equipments is growing.