You heard that right. The erratic power cuts have a fresh new cause now and this time it is strong winds. ZETDC put out a statement telling its valued customers that the current crop of strong winds is affecting the electricity supply in some parts of the country.
ZIMBABWE ELECTRICITY TRANSMISSION & DISTRIBUTION COMPANY
NOTICE TO OUR VALUED CUSTOMERS: NATIONWIDE
The Zimbabwe Electricity Transmission and Distribution Company (ZETDC) would like to apologize to its valued customers nationwide for increased power outages. This is due to increased windy conditions affecting some parts of the country leading to increased incidences of faults.
Our teams are working round the clock to ensure full restoration of service. The inconvenience caused is sincerely regretted.
Stakeholder Relations (09/10/2022)
For more information contact us on :ZETDC twitter page
Email: email@example.com Twitter: @ZetdcOfficial Facebook: ZetdcOfficial Website : www.zetdc.co.zw WhatsApp:+263715519387 / +263715519389 Call Us on: 704 / 08688003485 / 08688003486
Is it a genuine problem though?
Windy conditions or even extremely windy conditions are something that is factored into the design of power distribution infrastructure. The structure of high-voltage power line pylons has such loads calculated in it to ensure that they do not fail from a mere gust of wind.
As for lower voltage lines that deliver power to our homes, the effect the wind has on them is quite low to the point where they are pretty immune to any effects of strong winds. So it’s safe to say unless the infrastructure has gone beyond its service life and its structural integrity has deteriorated, it’s not going to be affected by any kind of strong wind.
However, the electricity supply infrastructure exists in an environment with other objects and structures which may not be as resilient to strong winds as the electricity distribution infrastructure itself. Trees are the biggest problem. In strong winds, some trees bend at very extreme angles such that they can interfere with power lines and cause short circuits.
Essentially forcing different electrical wires to directly come into contact. This can cause a substation delivering power to your house to trip the same way an overload on a socket in the house can cause the switch to trip in the distribution box and kill power to all the sockets in the house.
In some worse cases, a tree can break and fall onto power lines which may result in cable breaks that take even longer to revive. Again causing some extensive power cuts. So even though strong winds don’t really affect powerlines in isolation, other structures that exist around power distribution infrastructure can fail due to strong winds and disrupt this power infrastructure. Something that will come back when the rainy season starts.
The reality of Zimbabwe’s power situation
ZPC’s Q2 2022 report gives a nice summary of what’s really going on.
The output for the quarter was 6.39% above the output in Q2 2021. This is attributed to increased water allocation from 15Bm3 in 2021 to 22.5Bm3 in 2022.ZPC POWER COLUMN Q2 2022
Essentially what is being said here is the water allocation for power generation at Kariba Power Station was increased by 33% and so far this 33% has yielded 6.39% more output. Remember Kariba dam generated 72% of the total power generated in Q2 2022.
Now let’s take a look at the dam levels. As of 3 October 2022, the water level at Kariba dam was at 16.49% which is less than half of the water level on the same day last year which was at 38.34%. The rate of consumption of water in the dam is at 2.54% every 10 days meaning the remaining water is enough for 65 more days of power generation or just over 2 months.
Meaning by mid-December the lake will be too low to generate power. And the data provided by the Zambezi River Authority suggests that levels begin to rise in January. But at this very point, the lake level is at its lowest since the 1995/96 drought!
What does not help the cause is that Hwange Power Station is still getting work done on it and so is not producing peak power. Currently, ZPC states that the progress on Zimbabwe’s largest thermal power station expansion is at 89.5%. But regardless it’s currently only contributing 27% of the total energy output which is not enough to supplement Kariba. There again is also another slight issue of coal supply shortage at the Hwange Power Station and other thermal power stations countrywide.
To alleviate coal supply challenges faced by thermal power stations, cabinet approved for a long term coal supply agreement which will see coal suppliers getting long term bank financing they need to expand on their production.ZPC POWER COLUMN Q2 2022
So really the recent windy weather’s contribution is inconsequential in the recent power outages when compared to the bigger picture which is that our biggest power generating plant is running out of water and the second biggest one is not doing any better nor does it have the capacity to stand in for the biggest one. The solution for now looks like solar doesn’t it? I have a solar system buyer’s guide for Zimbabwe ready for you.