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The move by the Zimbabwe Power Company to involve investors from the private industrial sectors to help refurbish the three old thermal power stations at Bulawayo, Harare and Munyati in return for guaranteed power supplies makes a lot of sense for both Zesa and industry.
Even at their height in the later 1950s, the three stations were small, with a maximum installed total capacity of around 375MW although, as would be normal, the average output would be a little less.
The stations thus met the total requirements of the colonial Southern Rhodesian demand using roughly what Hwange 7, ZPC’s largest generating unit, now supplies on its own.
Although the equipment in the three stations is, at its newest, pushing 70-years-old, the three moved from the prime electricity generators to back up and supplementary power when Kariba South came on stream from 1959.
While that power had initially to be shared with Zambia once the north bank station was commissioned the three thermals, even then starting to be called the “old thermals” were more back up.
They were increasingly needed, at least for peak power, through the 1970s and early 1980s, but went back to emergency generators when Hwange Thermal came on stream to complement Kariba South.
There were discussions in the 1980s about their refurbishment, but this tended to get lost in the discussion over Hwange expansion and a second very large thermal station and then the public debate about where the second big hydro scheme would be built, at Mupata or Batoka Gorges.
Today ZPC is lucky to generate a little under 50MW from the three, although this could probably be doubled with some investment into major repairs and even new modules for some of the generating units.
To put all this into perspective the smallest unit at Hwange Thermal is 120MW, and the four units of that size commissioned in the earlier 1980s all need major work.
Whatever cash ZPC can raise would obviously give far greater results on getting those up to scratch, and then the slightly more modern two 220MW units at Hwange, than on squeezing out a few more megawatts from the three small stations. And when it comes to costing Zesa and its generating subsidiary need to look at bang for the buck.
But those three old thermals are there, and their position is rather important. Even with diversification of industry and expansion of industry across the country, there are still high concentrations of industry in Harare and Bulawayo and in the central Midlands, the precise locations of the three older stations.
This is what could well make them attractive for some heavy industry in those areas. Many companies have been investing in solar, some with fairly large arrays, and while solar is ideal for a lot of business done in “business hours”, that is the day time, and for processes that do not demand really serious power supplies, thermal power makes sense for others.
ICT and the like can operate in a solar environment, but the really heavy industry that needs a 24/7 consistent power supply, and guaranteed 24/7 at that, might well want to be old fashioned.
Coal-fed thermal has taken a lot of knocks in recent years, and where alternatives exist or make sense should not be used let alone expanded.
But it has many advantages, at least in countries with reasonable coal reserves as does Zimbabwe. For a start it is climate-proofed, even if it can add to global warming.
Hydro, as we know, is great when the rivers are running strongly and there are decent flood waters that can be stored, but has to be cut back in drought years.
Solar works well, except obviously at night and regrettably is not so good in winter, when demand increases, and diminishes in heavy cloud. So there is a market for continuous power regardless of the season or the rainy season.
Of course some major industrial companies may feel the dubious publicity of using coal power is a downside, but they can take that into account by what is formally called carbon sequestration, and what most people would see as planting trees.
All coal arises from trees and other plant material that fell into swamps and lakes millions of years ago, so when we burn it we must replace the sequestered carbon with new trees and plants.
This is the main reason why Zimbabwe, at present, has a negative carbon footprint despite all the coal we burn and the cars we drive. Those forests across the nation absorb more carbon than we burn.
At the moment, land for trees would not be problem for industrialists investing in the thermal power stations. If they look out of their windows they can see the sunbaked roads and pavements of our average industrial areas.
Cooperation with the local city council could easily see those streets becoming lined with trees, with many other advantages besides just sequestering carbon. The industrial sites would look a lot better for a start.
The investment in upgrading their surroundings would not be expensive. Saplings are cheap and digging holes is not a sophisticated industrial operation. A bit of fertiliser would be needed at the start, and some way of diverting non-oily non-poisonous waste water, which a lot of companies generate, would be a help.
And those who wonder whether side of road trees would absorb much carbon should consider Harare Avenues and Harare Gardens. The volume of those trees planted early last century must now be immense.
It should also be possible to find other land for timber plantations, such as along the rivers and streams within the cities and on public land nearby.
One useful function trees have for carbon sequestration is that forests can be harvested so long as trees are replaced. It is the wood that ties up the carbon, whether it is in a living tree or is a roof truss or a school desk or a lounge suite.
Mines can get double benefit from afforestation. Mine dumps, even by the most careful of miners, are not the most attractive surface features in our countryside, and often need to be returned to nature. But research has found a number of tree species that, with a bit of help at the beginning, can cover a dump with trees and turn it into forest.
So miners can get their carbon footprint down, or even negative, and make use of their dumps by going a tree-growing route.
What is important when we move towards a green world is not so much the amount of atmospheric carbon a particular process produces, but what the total impact it if the emission of carbon dioxide is counterbalanced by carbon sequestration, that is in Zimbabwe by new trees with the addition of harvested timber used to make things, rather than just being burned.
When one looks at annual reports of businesses in many countries these days there is a section of the carbon footprint, a vital point, and some businesses go a long way to keeping that very low through a wide range of methods that include creating new forests along with using alternative energy, and when they use coal or oil in counterbalancing this with what they are doing to absorb the emitted carbon.
Zimbabwean industrialists, or at least those who want assured power supplies every day and night through drought and flood and even cable faults, can still join ZPC in its operations, and can still have a high-profile low-carbon operation.
Online Reporter