Video Transcript
Electricity demand increases over
winter. Which of the following reasons best
explains why that is?
Now, we’ve been given four reasons
here. So let’s go through them one by one
and see which one is correct.
Number one Electricity is cheaper
in winter, so people switch from heating their homes with gas or oil to heating
their homes using electric heaters.
Well, this one is not true. Electricity is not cheaper in
winter. In fact, sometimes, because of the
increased demand, electricity can become a bit more expensive in winter plus the
other statement assumes that a lot of people are heating their homes with gas or oil
and this is not really the case anymore.
And also during summer, why would
you want to heat your house in the first place? Houses are usually hot enough to
not need heating during the summer months. And this is also true for a lot of
spring and autumn. So for these reasons, number one is
not the answer to our question. So let’s move on to number two.
“Many electrical appliances are
less efficient in colder temperatures. Thus a greater electricity supply
is needed for the same appliances to work as well.”
Well, this one’s not true
either. In most cases, an appliance’s
efficiency has nothing to do with the temperature in which it operates. And certainly, if there are devices
that are less efficient in winter, then the efficiency differences are not large
enough to warrant such a difference in the amount of electricity supply. Therefore, this statement is not
our answer either.
So number three then, “During
winter, the weather is colder and it gets darker earlier in the evening. Demand for electricity increases
because electrical appliances are being used to heat and light homes for a while
longer each day.”
Now, this statement makes
sense. We know that the weather is colder
in winter; that’s why it’s the winter. And also, we have fewer hours of
daylight during the day. Hence, it gets darker earlier in
the evening. So let’s say in summer, it gets
dark around seven pm. So at that point, we switch on the
lights to light our houses. However, in the winter, let’s say
it gets dark around five pm. Well, we switch on the lights
then. So we’re spending an extra two
hours lighting our houses every day.
Not only that, but it’s colder in
the winter. So we need to use electric heaters
to heat our houses. And this is something we don’t
necessarily need to do in the summer, especially if it’s a warm day. Therefore, it’s the combination of
the lower temperatures and the earlier dark hours that result in an increased demand
for electricity over the winter.
So this one looks like it’s the
right answer. But let’s go for number four anyway
just to make sure.
So number four people stay indoors
more in winter and therefore spend more time doing activities that involve
electrical appliances, such as watching television.
Well, this statement is not
technically incorrect. People do tend to spend more time
indoors during winter time and inevitably this does result in more electrical
appliances being used. But the effect of this is no way
near as large as the effect of the colder weather and the earlier dark hours. So we can safely roll this one out
as well.
And hence, we have our final
answer. The reason that electricity demand
increases over winter is that during winter, the weather is colder and it gets
darker earlier in the evening. So the demand for electricity
increases because electrical appliances are being used to heat and light homes for a
while longer each day.