Environmental Engineering Reference
In-Depth Information
ever be rendered redundant, having the generation of electricity at or near
the point of its consumption.
Demand-side
But the really
exciting aspect of smart grids is on the demand side, with
the possibility of changing consumer behaviour in order to tackle the
problem of peak demand. This problem is uniquely difficult in electricity,
because you can't store it in any significant way. Supply and demand must
match - electricity has to be consumed the moment it's generated, and the
moment it's demanded it must be produced.
In order not to be caught short by some unexpected peak in electricity
demand, utilities need to keep some back-up generators spinning away,
ready to be hooked up to the grid at any moment, but which might be
used only rarely. In the UK, according to a recent Brattle Group study,
nearly seven percent of generation capacity is used a mere one percent of
the time during a year, at moments of highest peak demand. Building and
maintaining generators that produce electricity for less than a hundred
hours a year is a waste of money, and operating these generators as spin-
ning reserve is a cause of needless greenhouse gas emissions. So, to remain
with the UK case, if peak demand could be lowered during this one per-
cent of the year or shifted in time, then the UK could avoid building that
extra seven percent of generation capacity. This would make a much more
efficient system: money and emissions would be saved.
But how do you go about anticipating, lowering, shifting or re-shaping
the power demands of an entire nation's households and offices? That is
where smart meters come in. These do what ordinary gas and electricity
meters do today - measure consumption in order to bill the customer.
However, smart meters do not require electricity or gas company per-
sonnel to turn up in person at a house or business to read the meter.
Smart meters can transmit up-to-date consumption figures to be read
electronically either to utility trucks going up and down streets or
directly back to the supplying energy company.
This is why, even in the UK, which is a latecomer to smart metering,
energy companies are beginning to advertise an end to estimated bills,
which often arrive through the letter box months after you've used the
electricity and are frequently inaccurate. So far the only country to roll out
this sort of smart meter on a national scale is Italy. While it was still Italy's
state electricity company, Enel decided on a national campaign which
installed 27 million smart meters between 2002 and 2005. The company
