First PV Diesel Hybrid System in the Megawatts Goes into Operation

The first PV diesel project in the megawatts was commissioned in Thabazimbi in November 2012 and, as a future development engineer, I was granted the opportunity of being present for the commissioning of this flagship project.

Rising diesel prices naturally result in high costs for everyone. However, this is especially true for industrial large-scale consumers in off-grid regions. Industrial companies in sunny regions can counter this trend with solar energy by integrating a PV system into a diesel system. The SMA Fuel Save Controller offers a solution for industrial plant operators to minimize fuel consumption while significantly reducing CO2 emissions. SMA completed its first project combining diesel generators and PV systems at a chrome ore mine in South Africa.

The project: a chrome mine in South Africa

Thabazimbi, Limpopo, South Africa, November 17, 2012, 2 p.m. – nothing as far as the eye can see, except for grass and bushes. The area is virtually unpopulated.   The only thing disturbing the idyllic setting is a loud, rattling motor sound which can be heard long before anything can be seen. Two 800 kVA diesel generators thunder away, providing electrical power for a young chrome mine. The mine is located in an area too remote to be supplied by a utility grid.  Therefore, conveyor belts and mining equipment are powered using diesel generators. The quicker the mine operates, the more expensive it is to run, and the more CO₂ emissions it produces.

Solar Saves Diesel

Suddenly – as if at the push of a button – the deep thundering of the generator dwindles to a quiet hum. The power provided by the diesel engine is reduced by almost 90 percent within seconds. In conventional stand-alone diesel grids this happens frequently when a large load is switched off or another diesel generator is connected. But not in this case. Instead, photovoltaic energy has actually been fed into the system with the simple push of a button – controlled by the SMA Fuel Save Controller prototype. It controls the 1 MWp system with 63 SMA Sunny Tripower 17000TLs so that a majority of nominal system power can be covered by PV energy without compromising system stability in the process.

“Luckily, We Were Only Sweating Because of the Heat”

The commissioning of the pilot project went smoothly. Luckily, we were only sweating because of the heat. The only problems that came up were of an organizational nature as the work sequences in Germany and South Africa needed to be coordinated and carried out with various project partners. With regard to the technology, however, everything went according to plan. The SMA Global Support Team provided support in the commissioning of the Sunny Tripowers, and the service employees at our newly founded SMA subsidiary in Centurion, South Africa, provided valuable on-site assistance. Without them, we probably wouldn’t have even been able to find the mine so easily.

Huge Potential for PV Energy Worldwide

There is great potential for the use of PV systems in off-grid diesel systems. In 2011, nearly 50 GW of diesel generated nominal power were sold worldwide, including approximately 40 percent running in industrial stand-alone grids, primarily in grid-remote regions with high levels of solar irradiation.   If the price of diesel is above US$1/liter, the integration of a PV system into the stand-alone diesel grid would have already have been amortized after only a few years. A PV diesel hybrid system ensures the stability and even a reduction in the levelized cost of electricity generation.

Valuable Experience for Future Projects

These advantages have convinced the mine operators about the power of PV diesel hybrid systems.  Over the next few months the system will provide us with a lot of data which we’ll be able to use for future projects. In this way, we can further optimize the Fuel Save Controller – which will be available in a few months – and adjust it to the needs of ongoing operations.

Find more information in our press release.