Hydropower is gaining renewed attention in South Africa.
Over the past year, more farmers and agri-businesses have started looking at water not only as a source of life for crops, but also as a dependable source of electricity. The reasons are clear. Hydropower provides reliable base-load energy — generation that runs day and night as long as there is water flow. It is not dependent on sunshine or wind, and it is built to last.
While a solar system may need to be replaced two or three times over the life of a single installation, a well-built hydropower plant typically operates for 60 to 100 years. For farmers investing in long-term infrastructure, that kind of durability matters. The performance gap is just as striking: a good hydropower project can achieve a capacity factor of 60 to 70%, and in places like the Fish River system this rises to around 90%, while wind in South Africa averages 35 to 40% and solar only about 25%.
For a hydropower project to succeed, the river’s flow must be steady throughout the year. Engineers measure this in terms of capacity factor, which shows how much of a plant’s maximum potential is actually realised. A good hydro project should reach around 60–70%. In South Africa, few systems offer this kind of reliability. The Fish River in the Eastern Cape, supplied from Gariep Dam, is one. The Katse-to-Vaal system, where dam releases ensure steady flows, is another.
Fish River projects
On the Fish River, I&F Engineering has completed several projects in the past three years with exceptional results. Capacity factors have reached 90%, far above the national solar average of around 25%. Farmers such as Michael Vermaak near Cookhouse are already benefitting, with three turbines (280 kW, 450 kW and 500 kW) running and a forth 1 200 kW unit planned to be installed by the end of the year. Michael utilises the head between the canal and the river below as for Chris Landman, also near Cookhouse who operates a 500 kW turbine set, while Japie Marais near Cradock operates a 300 kW plant. For these farmers, hydropower has become a dependable ally in keeping pumps, dairies’ pack houses, and irrigation systems working totally off the grid – no Eskom needed. These projects utilizes heads between 9 – 34m and flows between 3 – 5 m³/s
The story is not the same everywhere. In the eastern regions, many rivers flow strongly most of the year with a small reduction in the drier months but still keeping capacity factors acceptable. In the Western Cape, however, rivers with excellent heads available, often have small catchment areas and dry up in the dry summer months and the capacity factor drops to below 50%. Here, the most effective solution is to combine hydro with solar. In summer, long sunny days keep solar plants productive while river levels drop. In winter, when solar output falls, rainfall brings the rivers back to life and hydropower takes the lead. The two complement each other, creating a balanced, year-round solution.
To handle rivers that rise and fall with the seasons, the ideal turbine technology is key. I&F Engineering opt to install Crossflow turbines, which are well-suited to farms and small hydro sites with variable flow through the year. The design effectively acts as three turbines in one, dividing water flow into one-third, two-thirds, or full flow. That allows the turbine to run at peak efficiency of around 85% whether the flow drops to 17% of designed capacity or flowing at 100%. This flexibility is crucial when the turbine delivers “Off Grid” energy as the generation must follow the energy demand and therefore turbine need to control the flow continuously as the demand changes.
With only one turbine, one generator, and one control system, capital investment is lower. Maintenance of this Cross Flow Turbine is very simple: farm workers grease four bearings once a month, a task that requires little more than a standard grease gun. Installation is also easy and straightforward, with the turbine mounted on the floor of a small powerhouse over the outlet canal. I&F Engineering sources these turbines from Ossberger in Weissenburg – Germany, a manufacturer known worldwide for robust and efficient designs. It is normal for these turbine to run for more than 60 years with minimal maintenance, proving their value over time. Currently there are more than 10 000 of these turbines operating worldwide.
Cleanest renewable energy
Hydropower is widely recognised as one of the cleanest forms of renewable energy. Unlike technologies that leave behind complex waste, old turbines can simply be recycled at the end of their lifespan. With low maintenance and minimal environmental impact, hydropower remains a farmer-friendly, sustainable energy choice.
Hydropower is not new to South African farming. One of the most established and fascinating examples is at Komati Fruit Group’s Crocodile River Estate farm near Nelspruit. Formerly known as Croc Valley Farm, this estate installed its first turbine in 1926 to drive irrigation pumps. For nearly a century, that machine served faithfully. Now, Komati Fruit Group is writing a new chapter. Crocodile River Estate is upgrading to a modern 470 kW Ossberger Crossflow turbine set to power the entire estate.
An older, smaller Gilkes turbine from 1946 is still delivering 160kW from 500 l/s; a 65m head will be mothballed as the new turbine takes over its water supply as well. With a larger head available, the new system will generate more power from the same volume of water. The project began earlier this year and is scheduled for commissioning end of November 2025. Water will still be drawn from the century-old canal, but with a new abstraction point fitted with a trash rack cleaner to keep debris out.
From the fore bay, an 800 mm steel pipe (penstock), stretching 680 metres, will convey 850 litres water per second down the slope to the turbine, creating 74 metres of head. The new plant will generate in parallel with the Mbombela Municipality grid but can also change to “Off Grid Mode”. Initially, it will produce only enough power for the estate, but once a new Eskom connection point is secured, surplus energy will be wheeled through the grid to other Komati Fruit Group farms. Importantly, the turbine is also equipped to operate in off-grid mode, keeping the farm powered during load shedding, even if the rest of Nelspruit is dark.
The new plant will be registered as a renewable energy producer, which means it will generate Renewable Energy Certificates (RECs). Each megawatt-hour of electricity equals one REC, which serves as proof that the power is renewable. This matters because energy wheeled through Eskom’s grid can only be claimed as “green” if backed by these certificates.
Renewable Energy Certificates
As global demand for clean energy rises, the value of RECs is climbing steadily. In South Africa, RECs are increasingly traded at prices that make them a meaningful addition to a project’s financial return. For farmers, this means that every kilowatt-hour produced is not only cutting costs and protecting against load shedding, but also building a secondary revenue stream. For investors, RECs provide reassurance that their capital is tied to a certified, future-focused asset with environmental and financial returns. At the moment a REC is trading at R 236.00. This means 23.6 cents per kilowatt hour (kWh).
Hydropower has always carried a deeper value for farming than electricity alone; it represents security in uncertain times, independence from fragile grids, and a legacy that endures across generations.
As the demand for stable, sustainable power grows, I&F Engineering will continue to work with landowners, communities, and investors to identify viable sites and deliver projects that last — and we welcome enquiries from those exploring hydropower opportunities on their own farms or developments, ensuring this technology remains a cornerstone of South Africa’s farming and investment future.
I&F Engineering are also managing larger projects on farms where the aim is to sell energy to bigger clients like the mines.
The current list of projects available for investors are:
- Sabie Tevrede Hydro – 2.3 MWatt,
- Bivane Dam – 2.1 MWatt
- Sabie Uitsig Hydro – 2.3 MWatt,
- Wolwas Hydro – 5.3 MWatt,
- Grassridge Dam – 3.4 MWatt
Anyone who is interested in investing in these solid projects is welcome to contact me.
*Ian de Jager – 0825770677 ian@ifengineering.co.za
The author Ian de Jager is MD of I&F Engineering.
