National and global energy demands and resources
Energy needs
Nearly everything requires The capacity for doing work. and a way to use energy is by transferring it from one The different ways in which energy can be stored, including chemical, kinetic, gravitational potential, elastic potential and thermal stores. to another.
Systems that can store large amounts of energy are called Useful supply or store of energy.. The major energy resources available to produce electricity are Natural, finite fuel formed from the remains of living organisms, eg oil, coal and natural gas., Radioactive materials, usually uranium or plutonium, used in nuclear reactors., bio-fuel, wind, Electricity that is generated by the movement of water. , Energy from the heat of the Earth., tidal, water waves and the Sun. Ultimately, all the energy on Earth originally comes from the Sun but has been stored as different energy resources.
Energy is needed in:
- homes - for cooking, heating and running appliances
- public services, eg schools and hospitals - running machinery and warming rooms
- factories and farms - operating heavy-duty machines and production chains
- transport - buses, trains, cars and boats all need a fuel source and some trains and trams connect to an electricity supply
However, producing and distributing electricity can cause damage to the environment. Releasing energy from some stores causes pollution and harmful waste products. Burning fossil fuels releases carbon dioxide, adding to the greenhouse effect, and sulphur dioxide which causes acid rain.
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Patterns and trends in use of energy resources
During the The process that transformed manufacturing from handmade to machine-made, mass-produced goods using water, steam and coal power transported by canal, rail and steamship. Britain was the first country to have an Industrial Revolution., advances in automation and transport caused a significant increase in the amount of fossil fuels extracted and burnt.
In the 20th century, electricity became a convenient way of distributing energy. This powered a wide range of devices and applications such as lighting, heating, computing technologies and operating machinery.
Demand for energy varies with the time of year and the time of day. During early evening a lot of energy is needed for heating, lighting and cooking but overnight there is very little needed while people sleep. During winter there is more heating and lighting required than in summertime.
Global energy consumption
Most of the electricity generated globally is still produced by fossil fuels. This is partly due to:
- the high power output fossil fuels give compared to other energy resources, like wind and water waves
- the existing The basic structures needed for an area to function, for example roads and communications. for extracting, transporting and processing fossil fuels - this makes fossil fuels cheaper than setting up new alternatives
The recognised impact on the environment of burning fossil fuels has caused science and society to develop the use of Energy sources that are replenished and not exhausted, eg solar power. energy resources and make machines more efficient.
In some Refers to a country that has a lot of wealth or a population that is healthy and well educated. countries, nuclear power stations are a growing form of electricity generation. Nuclear fuel can release large amounts of energy compared to fossil fuels and does not emit carbon dioxide. However, the radioactive waste that is produced is difficult to store and dispose of.
Other factors that could influence governments鈥 decisions about the use of energy resources are political and economic pressures. For example, countries where the economy is heavily based on extracting and exporting oil, have a strong interest in fossil fuels to be largely used in electricity generation. In order to compete with more developed countries, growing countries like China need a large power output to keep growing their industry. This means they are likely to continue using fossil fuels and developing the use of nuclear power, alongside increasing supply from renewable sources of energy.