The diagram shows the consumption of renewable energy in the USA from 1949-2008. Write a 150-word report for a university lecturer identifying the main trends and making comparisons where relevant.

The line graph compares the consumption of four different sources of renewable energy in the US from 1949 to 2008, measured in

Quadrillion

BTU

.

It is clear that

the total consumption of renewable energy increased significantly over the period, with Hydroelectric

Power

being the most popular source.

However

, there were

also

some variations and contrasts in the trends of each source. In 1950, Hydroelectric

Power

and Wood accounted for nearly 2

Quadrillion

BTU

each,

while

Biofuel and Wind were negligible. Over the next two decades, Hydroelectric

Power

increased slightly to about 3

Quadrillion

BTU

,

while

Wood remained stable. From 1970 to 2000, Hydroelectric

Power

fluctuated between 3 and 4, before dropping to just over 2 in 2008. Wood,

on the other hand

, rose gradually to about 3 in 1989, and

then

fell steadily to around 2 by the end of the period.

In contrast

, Biofuel and Wind only started to be consumed from 1980 onwards, with very low amounts. Between 1980 and 2000, both sources grew slowly to less than 0.5

Quadrillion

BTU

.

However

, after 2000, Biofuel surged dramatically to almost 2 in 2008,

while

Wind peaked at less than 0.5 in the same year.