Alternative Energy Sources

As the most common and popular forms of energy are being used up quickly, the search to find new sources of energy is underway. These sources of energy must be renewable and not cause the pollution that fossil fuels do .

Solar energy

The sun can provide us with all the energy we need, for free ! The main problem is to collect and store this energy in an economicalway.

Today, we can capture energy from the sun with plates or cells. Collectors put on roofs of houses and other buildings turn solar energy into heat. With this energy we can heat up water or the air inside.

Solar cells convert the sun’s light directly into electricity. They are used in small objects like watches and pocket calculators .

In deserts and other subtropical areas sunlight is captured by big mirrors that turn it into heat. Water, which is 30 times hotter thanboiling point, then creates steam which, in turn, produces electricity.

Geothermal energy

Geothermal power can be produced in places where water comes into contact with hot rock below the earth’s surface. The water that reaches these hot areas turns into steam, which then produces electricity. In places where no natural underground water suppliesexist, engineers pump it into the hot rock layers.

Geothermal heat is an important source of energy in countries that lie in volcanic areas, like Iceland, Italy, New Zealand, California or the Philippines. Geysers are eruptions of hot water that come to the surface. Such naturally heated water is used to heat homes and greenhouses. 

Steam rising from a geothermal power plant in Iceland

Wind energy

Windmills have been used for centuries to grind grain and pump water out of areas that have been flooded, like the Netherlands or the northern parts of Germany.

Today, large wind generators turn the power of wind into electricity. Suchdevices, however, can only be used in places with strong and constant winds. At the moment, though, costs are too high to produce wind energy on a big scale.

Tidal energy

Tidal energy comes from the movement of ocean waves. One way to use the power of waves is to seal off a bay with a dam. When water moves into and out of the bay it turns a turbine, which produces electricity.

There are some coastal areas around the world where the difference between high and low tide is up to 10 metres and more. Great Britain, the Netherlands, Germany or France have coastal regions where such power can be created. 

Tidal power plant on the French Atlantic coast

Nuclear Fusion

Fusion may solve all our energy problems. Hydrogen atoms are united and can produce large amounts of energy. In contrast to the splitting of atoms fusion is safer and does not produce a lot of nuclear waste.

We have an almost endless amount of hydrogen in our oceans but, up to now,scientists have not yet come up with a way to produce large amounts of such energy. Such a system, which produces cheap energy from our oceans, will probably take years or decades to develop.

Biomass

Biomass is material that comes from plants and animals. It contains energy that the sun has produced and when burned produces heat. Wood , plants and crops are the most important sources of biomass today.

Biomass can also be changed into other forms of energy , like gas, ethanol or bio diesel. In Brazil, for example, about 20 % of all cars are driven by ethanol, produced from sugar cane. Biomass is also a renewable source of energy because crops and trees can always grow.

 

Words

• amount =how much of something
• bay =part of the sea that is separated by a curve in the coastline
• big scale =here: a lot of
• boiling point = the temperature at which water boils
• capture = here: to get control of something
• cause = lead to
• common =widespread, normal
• contain = has
• convert = to turn into
• decade = a period of ten years
• develop =here: make , design
• device = machine that does a special job
• economical = cheap
• electricity =the power that is carried in wires and cables ; it gives us light , heat and makes machines work
• engineer = technician ; someone who does technical things
• eruption =outbreak of a volcano
• ethanol = here: alcohol that comes from plants
• fossil fuels = forms of energy like coal or oil that have been produced by dead plants or animals over millions of years
• fusion = atoms join together to produce power
• generator = a machine that produces electricity
• geothermal = heat that comes from inside the earth
• geyser = a hole in the ground from which hot water and steam come out
• grain = the seeds of plants like corn, wheat or rice that are used as food
• grind = to break up into small pieces or powder with a machine
• high tide = the time when the sea reaches its highest point
• hydrogen = a gas that forms water when mixed with oxygen
• in contrast =compared to; as a difference
• layer =material between two objects
• low tide = the time when the sea reaches its lowest point
• movement =when something moves
• plate = a flat metal object
• pocket calculator =a small machine that you use to do calculations
• pollution =when air, water and other resources get dirty, so that you cannot use them any more
• provide = give
• renewable = something you can use over and over again
• scientist =a person who is trained in science
• seal off = to stop something from coming in
• source =where something comes from
• split = to separate into two or more parts
• steam = the hot gas that water produces when it gets hot
• store = to put away for a longer time
• sugar cane = sugar that grows in tropical regions
• supplies =reserves
• surface =top layer of something
• tidal = everything that comes from the rising and falling of ocean waves
• turbine = a motor in which gas or water moves a wheel around
• unite = come together
• use up = to use all of something
• waste = materials that you don’t need any more or are left over