You don’t always have to turn off lights if..
We have always been told and reminded repeatedly to turn off unneeded lights to save energy, but this is not always true. If you have special energy saving light bulbs called CFLs, turning them on and off too often may shorten their life spans. So if you’re going to be gone just a few minutes you can leave them on.
Burning coal generates electricity, but not everywhere.
In Europe coal accounts for 25% of all the fuels burnt to generate electricity, in the United States 39% and 75% in China. When it is burned in a power plant it provides the heat to make steam which moves a turbine that generates electricity. In some places however coal is used much less, like in California where only 1% of electricity is generated from this fossil fuel.
Putting our clocks forward in Spring is good for the planet.
When Daylight Saving Time starts each spring, we move an hour of daylight toward the end of the day. In just four weeks of DST scientists calculated that we save 0.5% of electricity. This doesn’t sound like much but it is the same as 1.3 billion kilowatt-hours, the amount of electricity 100,000 houses use in an entire year.
The force in water makes electricity.
When you put your open hand in a stream or river you can feel how powerful the flow is. We can use this power to generate electricity. Thousands of years ago ancient populations built water wheels and mills to grind grain using the power of flowing water. Today many countries use hydropower, that is the electricity generated by water flow. Hydropower plants are usually inside dams. Sometimes dams are not built and part of a river is channeled to make electricity.
Wind can generate electricity too!
Even thousands of years ago people understood that wind is a strong force. They invented windmills to harness it. Like water, wind is a renewable energy source. Big wind turbines, sometimes over 100 meters tall, generate electricity today. They look simple but some have 8000 parts! Countries like the United States, Germany, Italy and Spain are making a lot of electricity using wind.
The sun’s power fuels a satellite for 50 years!
The sun is a great source of energy, its rays send Earth 10,000 times the energy we use all around the world every day! Space industry has used solar power for more than 50 years. In fact space craft use solar cells to capture this energy to this day. Vanguard1 was the first artificial satellite to use solar cells, it is the oldest artificial satellite still orbiting the Earth.
Trash can also generate electricity.
Why “waste” all the waste products that we flush down the toilet or put in our trashcans? When organic waste breaks down it releases methane, a natural gas. Trapping that gas is useful because it can be burned as a fuel to produce electricity. This has another benefit: methane is a greenhouse gas, when we use it we are keeping it out of the atmosphere. This is good for the environment.
Are electric vehicles great everywhere?
Electric cars don’t pollute the air when they go. They are powered by electricity in their batteries. But are they really non polluting? It depends on where you live. When you charge the car’s battery, you are getting electricity from a power plant. If this electricity comes from renewable sources, electric cars are great for the environment. If your power comes from a coal burning power plant then it is not as good. The car itself does not pollute but the electricity that charges it does.
More efficient batteries are the way to go.
Batteries have improved a lot since they were invented in 1799 but they need to be improved even more before we can store enough energy for us to use solar and wind power without running out of electricity on cloudy or windless days. We need to be able to store more energy for longer. Researchers are working hard to solve this problem.
Energy is measured in BTUs or calories.
Just like temperatures are measured in degrees which could be Fahrenheit or Centigrade, there is a unit of measurement for energy as well. This way we can make comparisons with our figures. In UK and USA this unit is the BTU (British Thermal Unit) which is the energy needed to raise the temperature of one pound of water by one degree Fahrenheit. In Europe and most of the world the unit is the calorie, the energy needed to raise the temperature of 1gram of water by one degree Centigrade.