[miningmx.com] — IT’S probably inevitable that people, like chickens,
will always start pecking the head of the sick one; if we assume people act like
chickens.
This chicken-like way of thinking is why Eskom is the black sheep of public opinion,
and will remain so until South Africa eventually has enough electricity again to keep
the lights on in empty buildings and for people to go on holiday without turning off
geysers.
This kind of thinking is also the reason for the hysteria when it was revealed Eskom
CEO Brian Dames, and his management team, had decided to spend R36m on family fun days for Eskom’s 43,473 staff
members as recognition for keeping the lights on during the winter of 2011.
It simply doesn’t matter that, in Eskom’s case, this R36m is less than R830 per
Eskom family. And why are Eskom’s staff members so special that a fun day should
be held for their families?
They sacrificed a lot to ensure the country had no major power failure or load
shedding in the previous winter. And because those families are making even bigger
sacrifices this year.
The fact is that Eskom, which for decades had surplus electricity, must constantly
manage electricity shortages nowadays.
Every strategy in Eskom is aimed at avoiding the situation of January 2008 when
the mining industry was forced to a halt. Nersa’s audit of these events showed the
country suffered production losses to the value of R50bn because of this load
shedding.
In the meantime, coal supplies at Eskom power stations, which was a major cause of
2008’s disaster, have been increased from 12 days of burning capacity in 2008 to
more than 40 days’ stock.
In addition, an extra 2,537 MW of generating capacity has been created by the
restoration of old power stations.
A proper programme of load-shedding protocol has even been drawn up to ensure
that it is applied in a more organised way and that people and organisations will be
informed in good time if load shedding becomes necessary.
A reserve margin of 15% is required for the stable management of such a large
network. In 2008, the reserve margin was between 6% and 8% – today it is often
less than 3%, and on critical days, such as earlier this week, less than 1%.
However, the best way to avoid load shedding is careful planning and
implementation of maintenance work on the fleet of power stations.
Maintenance work is mostly done in the summer when the demand for power is
lower. However, last year’s maintenance was also done in the winter because there
simply wasn’t enough time to make up the backlog.
This year even more maintenance is being done in the winter. In June, three large
units were turned off for maintenance work. No-one goes on leave in June and July
– not only maintenance staff, but all operational staff. In December 2011, no leave
was granted to employees in these categories either, and this will remain so for the
next two years, says Hillary Joffe, Eskom’s chief spokesperson.
Gideon du Plessis, Deputy Head of Solidarity, which represents about one-third of
Eskom’s staff, says the maintenance teams work 12-hour shifts. These teams, mostly
skilled technical personnel, are usually on stand-by when they’re off duty.
“Someone placed in a maintenance team usually stays in it for four months. It’s a
time of great pressure on a family if the father works in a maintenance team. He is
for all practical purposes away from home for four months,” Du Plessis says.
It probably isn’t very pleasant when you have such working hours and then the
country becomes hysterical because your boss holds a family day for you.
Last year, Eskom had a shortage of about 6 terawatt-hours (TWh) of electricity and
expects a shortage of about 9 TWh this year. This is a shortage of about 1,000 MW
of basic generating capacity – more or less one-third of one of its large coal power
stations.
The daily cycle of demand for power also fluctuates considerably less in summer
than in winter. When the maximum number of generating units are stopped for
maintenance work in the summer, the system is very difficult to manage safely for
the entire day because the reserve margin remains low for the whole day.
In the winter months – during peak-demand periods at night – a temperature
difference of 1 °C means that the demand increases by between 600 MW to 700
MW. In the summer months – at the hottest time of the day – the demand rises by
about 400 MW for every 1 °C that the temperature increases.
Every power station has a specific maintenance time table – for example, the
pressure boilers must be inspected every 12 or 18 months. This kind of inspection
can take up to two weeks.
Every six years, a mini servicing must be done which takes a month; every two to
three years interim repairs must be done which take seven weeks; and every six to
12 years, depending on the age of the unit, a general service must be done which
takes up to 60 days depending on the age of the unit.
Five of the nine coal power stations in Eskom’s fleet are older than 25 years and
require more maintenance work than previously. Another two – Arnot and Hendrina
– are already older than 35 years. Each power station has six generating units
consisting of a steam turbine and a generator.
The network was already under intense pressure in 2010 and 2011, so certain
maintenance programmes were postponed. By January, a backlog of 36 units had
built up, which now have to be serviced.
That backlog must be worked off by the end of 2013. To achieve this, all December
leave in 2011 was cancelled, and also leave for 2012 and 2013. More units had to be
turned off for maintenance work than were available for the stable running of the
system.
That’s why Eskom tackled a comprehensive servicing programme during the past
summer and even “bought back’ electricity from large consumers like chromium
smelters. In this way it bought time for large-scale maintenance.
Should Eskom succeed in getting us through the winter without introducing load
shedding, Dames can go right ahead and arrange more family days for staff.
After all, you can’t get maintenance work done by a stone.
– Sake24
