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It has been a bad week in Southern Africa for keeping the lights on as Eskom of South Africa, Zesa of Zimbabwe and Zesco of Zambia all hit major faults almost simultaneously.

In Zimbabwe the main problem was a serious fault at Hwange Thermal Power Station that reduced output to below 100MW, implying just one of the six boiler-turbine-generator units was operational and even that one was spinning at below its maximum capacity.

This output from the major thermal station, along with some small contributions from other stations, meant the main load was on Kariba South. Even with a willingness to go above the required water ration temporarily, and catching up later, Zesa has to be careful of how many turbines it can use at Kariba in daylight hours as work continues on the downstream plunge pool.

South Africa appeared to be having similar problems. Eskom swiftly moved the country into level four load shedding, which is quite tough, on Monday as a number of generator units were down and while more power was expected to come onto the South African grid this week, load shedding, at least at a less severe level, was expected to continue over the weekend.

Zesco of Zambia, which will its two major hydro stations at Kariba North and on the Kafue can normally produce enough for modest exports, was hit by a fault that suddenly cut Zambia off Southern Africa grid and caused a temporary national blackout. 

The South African and Zambian problems meant that there was no way Zesa could quickly make emergency relations to import more power.

A lot of the problems in South Africa and Zimbabwe arise from skimped maintenance and a high level of reluctance to invest in new generation capacity until the present Governments came into office. In part the investment gap made some sense, since Southern Africa had a generation surplus until the early 2000s and putting in an interconnected regional grid did allow some postponement in plans to build new stations. Certainly Zimbabwe decided to switch from a determined self-sufficiency to a growing percentage of imports.

The maintenance skimping was a direct result of business and political pressure to keep the lights on and the wheels of industry turning without an increase in tariffs and without paying for new power stations while economies were growing. This worked for a few years, but sooner or later skimped maintenance means that power stations stop generating. It is the same as with all machinery, such as a car. You can keep driving for some time after missing a service, but eventually you need a tow.

Both countries, under a more determined political leadership, are trying to catch up. Eskom’s present management explicitly explained the problem and carefully laid out the accelerated maintenance programme now required, and the need to have more units down at any one time for maintenance or replacement. 

Zesa was not so explicit but has made it clear that Hwange, even at its best, can only generate at half capacity while the first six units, commissioned in the 1980s, are refurbished, a programme now in progress but still some way to go.

There was some nonsense a few years ago with so-called experts explaining that a thermal station only lasts 25 years. They can in fact last almost forever, but at times coal feeds, boilers, steam turbines, generators and transformers need to be replaced. Even hydro stations like Kariba need at times to replace the inlet valves, turbines, generators and transformers as these wear out, and this has been done at times at Kariba South. A thermal station by its very nature needs more frequent maintenance and parts replacement.

The Second Republic has understood the need for capital investment, first increasing capacity at Kariba South to give Zesa flexibility to cope with peak periods, and now with the extra 600MW being installed at Hwange to increase total output, a programme modestly delayed by Covid-19 but now back on course. 

To this must be added a private coal thermal being commissioned in stages, advanced plans for a coalbed methane station in Matabeleland North to come on line by 2025 and a growing number of modest solar stations in various stages of commissioning.

South Africa has its own plans, including a second nuclear station and more natural gas capacity. But in most cases it takes some years from a commitment to invest in a new station to having that station feeding the grid. Power stations are not instant investments.

Most people in Southern Africa will need to accept that the days of cheap electricity are over. It costs money to build new power stations and to maintain older stations, and users have to pay. This does not necessarily mean higher energy bills, but it certainly means that households and businesses need to think how they use electricity and how they use modern technologies to get more for every dollar spent and every kilowatt hour bought.

At the same time more people and businesses should be looking at Zesa’s developing capacity to have net metering, a common concept in some countries. Businesses installing an array of solar panels will probably have surplus on bright sunny days but need to buy grid power at night and on cloudy days. Zesa can now install meters that see the authority buying this surplus when the sun shines and selling grid power when it does not, with the customer paying for the net energy used.

This, along with energy saving technologies and even careful household and business decisions on how energy is used, will help everyone cope with the need to pay both the operational and capital costs associated with grid power, that is the viable tariffs, without having to spend that much extra. 

In any case, with the present growing emphasis on combatting climate change, there is a growing demand for far more efficient use of energy, so we can grow economies without wrecking the planet, and this also means there is ever more technology available to improve efficiencies.

But unless people are prepared to pay viable tariffs it is not much use complaining if power stations breakdown because there is not enough money for maintenance, or if there is simply not enough power to start with since the station that should have been ordered five years ago was never built. We can cope with proper tariffs with better energy management and reducing waste, but we need the extra energy to manage and we need that electricity supply to be reliable.

The bad week we are experiencing in Southern Africa should help all of us to concentrate out minds.