Energy-The Stuff That Keeps Us Going

There are lots of forms of energy, but what is energy exactly? Let's find out!

What is energy?

Physicist say energy is "the capacity to do work," meaning the ability to move something.  An example of work would be pushing a grocery cart - it takes energy  to push the cart down the aisle at the grocery store. But energy isn't just for moving things - it is the ability to change something. We use energy to change where we are, change things into food, change raw materials into things we use. We also use energy to change the environment around us by heating or cooling our homes.

Fossil Fuels

The sun we see up in the sky and that gives energy to the plants around us today, is what gave energy to plants millions of years ago. Just like plants of today, they were "producers"  using sunlight and carbon dioxide and water to produce (photosynthesize) their own food (chemical energy). When the plants, some were buried. Over millions of years, the heat from the Earth's core and pressure from rock and soil converted the chemical ebergy into very compact forms - coal, oil, and natural. This stored chemical energy is what we call "fossil fuels."

Hydroelectric

Most of our electricity in the northwest comes from hydroelectric plants that harness the energy of water flowing in rivers and streams from the mountains down to the ocean. The sun adds  "potential energy" to water when the water evaporates and adds rises into the sky. When it comes ut of the sky as rain or snow (precipitation) it then flows back down to the ocean.  The energy of the moving water as it flows down hill is used to spin turbines that convert5 the energy into electrial energy.

Nuclear

Uranium, which is the fuel used in nuclear power plants, were created when ancient stars exploded or went "nova." In these massive explosions, atoms are forced together so tightly that some stick together and make large atoms or new materials - such as Uranium.  (Everything element we know except Hydrogen and Helium is created in these explosions.) Because gravity makes things attract each other - all the stuff from these explosions eventually comes back together to form new stars and planets. The earth is made of matter from those stars and it contains all types of matter - including some Uranium. Nuclear power plants work by breaking apart Uranium and other very large elements. This splitting process (fission) creates a lot of  heat, which is used to make steam which spins a turbine to create electricity.

Wind-power

As the sun heats up the air, some rises and some settles, producing large air masses of different densities which move around each other. These moving air masses are called wind.  When we put a windmill in the path of the wind, it spins. In modern times we using this spinng to turn a turbine, which, you guessed it, makes electricity.  Some windmills don't make electricity, though, but directly drive some device.  Most of the old windmills we see on the prairies drive pumps that raise water for animals.  The Dutch used windmills to pump water, drive grinding stones to grind flour, mustard, paint, etc., and even run saws to mill lumber.

Solar

Even though all of the forms of energy above are ultimately driven by the sun, we usually use  the term "Solar Energy" to describe energy we get from today's sunlight. At IslandWood we have solar panels on the sleeping lodges that harness the sun's light energy to heat water for showers - just like when things get hot when they sit in the sun. Our classrooms have photovoltic (PV) panels that will turn sunlight (photons) directly into electric energy (volts). This is accomplished when the sun's energy excites electrons in the PV panel and moves them to other parts of the panel. Electrons, moving, or passing energy to each other, is the form of energy we call electricity.

What is renewable energy?

An energy source that we can use over and over again is called "renewable" energy. Renewable energy sources include solar energy, geothermal (using heat from inside the earth), biomass (chemical energy) from plants , and hydropower from water.

Nuclear fusion, the source of the sun's energy, comes from compressing hydrogen atoms together until they join to create helium and give of excess energy as heat and light. If we can figure out how to control the very high temperatures created by nuclear fusion safely here on earth, we'd have all the energy we'd every need as hydrogen is the most common element there is.

What is non-renewable energy?

An energy source that we are using up and cannot recreate in a short period of time. In the United States, we get most of our energy from nonrenewable energy sources - mostly fossil fuels (oil, natural gas, and coal).

Nuclear fission created in nuclear power plants is also considered not renewable. Elements used in nuclear fission such as uranium are in limited supply.

In addition to being used up, most non-renewable energy also creates environmental problems.  Fossil fuels put a lot of carbon dioxide back into the air that took thousands (or even millions) of years for plants to pull out of the air.  This is a main cause of global climate change.

Nuclear fission breaks uranium down into other elements that are still very radioactive, and remain so for thousands of years.  The whole process ends of concentrating uranium and other radioactive elements  - and we need to work out solutions of where to store these elements that cause damage to living things.

Where do we get energy?

Do you know where our energy comes from?

We use energy in two main ways: Electricity and Transportation.

About half of our energy use is used for transportation.  Almost all of our transportation energy comes from petroleum - a non-renewable resource.  (Over 80% of this energy is wasted.) Until we start using renewable resources for transportation, the best way the best way to minimize side effects from using fossil fuels is to use less. Be smart and combine trips.  Or better yet, ride a bike!

Electricity is used on our homes and manufacturing.  We use it because it's easy to move around in our electrical transmission lines. (Two thirds of all energy used to create electricity, though, is ultimately lost in these transmission lines!) In much of the United States, electrical energy comes from burning coal - a non-renewable resource. In the northwest, though, we have many mountains and rivers, so we get most of our electrical energy from hydroelectric plants.

Puget Sound Energy - the area's largest provider of electricity - reported the following sources for it's energy for the year 2003 - the most recent year with certified data.

All of these energy sources provide us the energy we need to live our busy ways. Think of the many ways YOU create, use, and save energy!

The Lawrence Livermore National Laboratory has a very interesting collection of charts that show where our energy in the U.S. comes from, and where it goes (how we use it.) Check out this interesting chart...