Angela Royston - How Can We Save Our World? Sustainable Energy

We all need energy. We need it to light and heat our homes, schools, and places of work. Without energy in the form of electricity, we could not cook, watch television, or play computer games. Without energy in the form of fuel, we would not be able to travel by aircraft, train, bus, or car.

Most of our energy comes from fossil fuels, such as coal, oil, and natural gas. Electricity is produced from these fuels in power stations. Natural gas is also used for central heating and for cooking. Oil is refined and used as fuel in aircraft, cars, trucks, ships, and other vehicles. Oil is also made into a vast range of synthetic materials, including plastic, paint, and detergents.

During the daytime, we receive free energy from the sun, which gives us light and heat. The sun also powers the wind and produces the movement of waves in the ocean. Sunlight, wind, and waves can be used to generate electricity.

This book focuses on electricity and the way it is generated. Some sources of energy, such as the wind and the waves, continue day after day. They are said to be renewable, or sustainable, sources of energy. Supplies of coal, gas, and some other sources of energy, however, are limited. One day these sources will run out, so they are described as non-renewable, or unsustainable.

PERSPECTIVE

The worlds biggest blackout

I was waiting for the local train when the lights flickered. Then it went black. I found my way upstairs and onto the street. [She then ran the nine miles home.] That night was great. Everyone from the neighborhood was sitting outside and catching up. The kids were surprised when they looked up and actually saw starssomething that never happens in Manhattan.

On the Engineering News Records website, a New York City worker tells of her experiences on August 14, 2003, when a massive power outage occurred across the northeastern US and throughout Ontario, Canada, affecting 50 million people.

The demand for electricity has risen rapidly in recent decades. The standard of living in rich countries, such as the US and Japan, and in poorer countries, such as China and India, has risen. More people own computers and other electrical goods, and many buildings are air-conditioned. All these things use electricity. As the demand for electricity increases, the stocks of non-renewable resources shrink.

FACE THE FACTS

This table shows the projected increase in world energy consumption between 2005 and 2030.

*Btu = British thermal units

Source: Energy Information Administration (EIA), International Energy Outlook 2008

Like most cities, the Japanese capital, Tokyo, consumes huge amounts of energy. Electricity is used to light buildings and the streets. Less visible is the energy used for heat, air conditioning, and transportation.

For thousands of years, people used sources of energy, such as wood, wind power, and sunlight, that were almost entirely sustainable. However, in the nineteenth century the Industrial Revolution introduced machinery that enabled people to access fossil fuels quickly and easily. Coal and oil were mined in increasing quantities.

Until the nineteenth century, people relied on animals for transportation, and burned mainly wood and other natural materials for heating and lighting. Candles were made from tallow (animal fat) or beeswax. Oil lamps, which burned olive oil or another plant oil, gave a brighter light than candles. The wind or running water was used to power machinery, for example, the wheels in mills that ground grain into flour.

This old Swedish windmill is no longer used but stands as a monument to the past.

Coal had been used since ancient timesit gave more heat than wood and was used to smelt iron. After 1775, when James Watt invented an efficient steam engine, coal began to be mined in large quantities. The steam that powered Watts engines came from water heated over burning coal. The first steam engines were used in Britain to pump out water that seeped into mines, but soon they were being used in factories and for pulling wagons along metal tracks. By the 1830s, railway carriages pulled by steam engines were carrying passengers between many British towns and cities.

The Industrial Revolution transformed the way in which goods were made and transported. Cheap goods were produced in factories and sold to people at home and abroad. The revolution spread from Britain to Europe, North America, and around the world, and it was driven by the move from sustainable energy to coal. The demand for coal increased dramatically.

FACE THE FACTS

About 5,000 years ago, the energy people consumed for their survival came mainly from plants and animals and averaged about 12,000 kilocalories per person each day. As society became more advanced, the demand for energy slowly grew until, in AD 1400, each person was consuming about twice as much energy (26,000 kilocalories). Following the Industrial Revolution, the demand almost tripled to an average of 77,000 kilocalories per person in 1875. By 1975, it had more than tripled again to a staggering 230,000 kilocalories per person.

This print of an early steam train evokes the excitement and opportunities that rail travel brought. Trains carried goods and passengers and were faster and cheaper than horse-drawn carriages and canal boats.

In 1831, the British chemist and physicist Michael Faraday invented the first dynamoa machine that could generate usable electricity. The electric telegraph and telephone were patented soon after. The most prolific inventor was Thomas Edison. He set up an inventions factory and filed patents for more than 1,000 inventions. One of them, in 1879, was for an electric lightbulb.