Now let's go back to the graph for 1997 and squeeze inside the bar for renewables
to see what kind of renewable energy sources were used to make electricity. Seven
different kinds of renewables Refer to graph 9) were used, but most of the electricity was made from hydroelectric
plants on rivers and streams. Power is made as water pushes against turbines inside
tunnels through dams. Traditional electric generating companies called utilities
made most of their renewable power from water. Non-utilities — other companies
and even families - also helped make power from renewable resources.
Graph 9
You can get another view by separating utility and non-utility generation so you
can see differences on how the renewable resources were developed. There are REALLY
big differences you couldn't see in the previous graph. In the utility graph
(Refer to graph 10), 97.9% of the
utility generation was from water. But non-utility hydroelectric generation was
only 20.5% as you can see in the non-utility graph. (Refer to graph 11)
Graph 10
Graph 11
Most of the non-utility generation was from burning wood, wood chips and sawdust
(40.4%), followed by burning the gas created from trash decomposing in landfills
(20.0%). One big reason for the difference is that some companies and people try
things because they think lots of people will buy the electricity at a certain price.
Other companies aren't so sure that many people will buy at that price, so they
don't want to spend their money developing the energy resource.
What are some reasons why some resources might be used more than others? One reason
could be the amount of the resource that is available. Maybe some electric generating
companies using one resource might start to begin to use another so they would still
be able to make electricity if there was to be a shortage of the original resource.
There are many maps of resources made by people exploring and estimating how much
of a resource there is:
You can see that states have different amounts of resources which is why they will
be used differently. There's a lot of coal in Ohio, but not much in Florida. But,
Florida has more sun than Ohio. Some places have more wind than others do, but all
states have some wind. Right now, the U.S. DOE says even though every place has
some wind, only wind strong enough to be a class 3 or higher can be converted into
electricity by today's wind turbines at a cost which most people are willing to
pay. Wind which blows gently will make electricity but at a price much higher than
most people are willing to pay.
DOE has lots of data for each state on the ways electricity is produced. Want to
know how your state compares to others? Check to see if your state ranks in the
top 10:
We graphed DOE data for all 50 states so you can check out your state and compare
electrical generation to the resource maps. Just click on the state that you want
to see!
You can see that each state matches up pretty well to the resources within it. Almost
all the states use coal and hydropower to generate electricity. Don't forget that
some don't have enough resources of their own, so sometimes resources are shipped
into the state. Oil can be used in the Northeast even though not much oil is found
there, and uranium is used in Florida's nuclear plants, even though it's not mined
in the state.
Now that you know more about why certain resources are used to generate electricity,
can you explain why your state uses the energy resources it does?
