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Insulation
It requires less insulation
(only at the contact point of
the tower).
It requires more insulation
(for
coating the whole conductor).
Cost
The overhead line is
cheaper.
The underground cable is
expensive
.
Fault
Very easy to repair and
clear the fault.
Very difficult to repair and
clear the fault.
Environmental
Impact
It gets impacted by the
occurrences
of
environmental attacks (like
lightning,
windstorm,
thunderstorm).
There are fewer chances of
environmental attacks in an
underground system.
Maintenance
The maintenance cost of
the overhead system is
high.
The maintenance cost of the
underground system is low.
Reliability
The
overhead
system
provides low reliability.
The
underground
system
provides high reliability
.
Write a paragraph comparing overhead power lines and
underground cables (50 words). Use linking words for comparison and
contrast
VIDEO
You are going to watch the video about one of humanity’s most
important and fascinating engineering achievements: the power grid.
Study the following words before watching. What do they mean?
Write a sentence for some of the words
ubiquitous
to take for granted
to take into consideration
to be capable of
distinct
to draw power
to perform an important role
to establish rules
participant
overarching
to keep track of
to deviate
to take into account
tremendous
ultimately
