Wind and solar can power hydrogen production, but when renewable electricity falls short, the consequences can extend far beyond a single process.
South Africa’s planned Prieska Power Reserve provides a case study for examining the engineering considerations involved in integrating wind, solar, and hydrogen production. While the project remains under development, its proposed configuration highlights how renewable electricity supply can influence hydrogen production and downstream industrial operations.
This article explores three potential challenges of integrating these technologies and the engineering approaches that could help maintain system reliability.
Renewable Fluctuations Change Hydrogen Output
Wind and solar renewable generation depends on weather conditions.
This means the electricity available for hydrogen production can change throughout the day. During periods of strong wind or sunlight, electrolysers, which use electricity to split water into hydrogen and oxygen, may receive sufficient power to operate at higher production levels. However, when renewable generation decreases, electrolysers may need to consume less electricity, reducing the amount of hydrogen produced.
A 2023 study titled “Technical evaluation of the flexibility of water electrolysis systems to increase energy flexibility”, examined three approaches to adjusting electrolyser operation as electricity availability changes: switching individual units on or off, distributing available power among operating units, and adjusting hydrogen production within each unit’s permitted operating range. These approaches are important because electrolysers have minimum operating loads and technical limits that restrict how much their power consumption can change. It also highlights that flexibility at individual stack level does not necessarily translate into flexibility across the entire electrolysis plant.
Hydrogen production capacity alone does not determine how effectively renewable electricity can be used. The key is to assess electrolyser flexibility by comparing manufacturer-specified minimum operating loads and allowable power ranges with expected wind and solar generation. In systems of this type, Programmable Logic Controllers (PLCs) can adjust electrolyser operation within these limits, while Supervisory Control and Data Acquisition (SCADA) systems can monitor electricity availability and equipment performance. Together, these control and monitoring capabilities can support changes in hydrogen production as renewable generation fluctuates, without exceeding equipment operating limits.
Shared Electricity Creates Operational Trade-Offs
According to SMEC, a global engineering and infrastructure consultancy involved in the planning and development of the Prieska Power Reserve, on its article on “Planning Advances at Prieska Green Ammonia Precinct”, approximately 90% of the planned Prieska Power Reserve’s energy supply is intended for electrolysers, with the remaining 10% allocated to synthesis and air-separation units.
Professionals must therefore balance the electricity allocated to hydrogen production against the energy required by downstream processes and the need to maintain sufficient battery reserves for periods of reduced renewable generation.
The proposed system also combines battery storage with a synchronous condenser to help manage fluctuations in renewable electricity supply. While battery storage helps balance electricity availability, the synchronous condenser supports voltage regulation and short-term power system stability during changing wind conditions. This adds another consideration to managing electricity for hydrogen production and other industrial processes. A November 2022 study on “Optimized Demand-Side Day-Ahead Generation Scheduling Model for a Wind–Photovoltaic–Energy Storage Hydrogen Production System”, examined how renewable generation, battery storage, and hydrogen production can be coordinated through day-ahead scheduling. This involves using forecasts of wind speed, solar irradiance, and expected electricity output alongside projected power demand from electrolysers and other industrial equipment. These estimates help operators plan when renewable electricity should be used for hydrogen production or stored in batteries for later use.
For the planned Prieska Power Reserve, producing more hydrogen immediately could leave insufficient stored electricity to support operations when renewable generation declines.
This requires assessing expected electricity demand against available battery capacity and forecast renewable generation to determine appropriate charging schedules and minimum state-of-charge thresholds. Energy Management Systems (EMS) can support these decisions by determining when to prioritize hydrogen production and when to preserve battery reserves for periods of lower electricity availability.
Interconnected Systems Increase Disruption Risks
When wind, solar, and hydrogen production are connected within one power system, a problem affecting one technology can also disrupt other operations. For example, at the planned Prieska Power Reserve, a prolonged period of low wind and sunlight could reduce electricity generation.
If battery storage and other electricity supplies cannot cover the shortage, electrolysers may produce less hydrogen, leaving less available for downstream processes such as green ammonia production. This means that an electricity shortage could first reduce hydrogen production, potentially leading to a separate hydrogen supply shortage that disrupts downstream processes such as green ammonia production.
A 2026 study on “Optimized Energy Management and Reliability Assessment of RES Based Microgrid”, discussed two measures for evaluating electricity supply reliability: Loss-of-Load Probability (LOLP), which estimates how likely a power shortage is to occur, and Expected Energy Not Supplied (EENS), which estimates how much electricity demand could remain unmet by simulating different operating conditions, such as prolonged periods of low wind and sunlight and equipment failures, then calculating how often electricity shortages could occur.
For the planned Prieska Power Reserve, preventing electricity shortages from disrupting hydrogen production and downstream chemical processes requires assessing the reliability of the entire power system.
Power system simulation tools such as DIgSILENT PowerFactory or MATLAB/Simulink can model periods of low renewable generation and evaluate whether available electricity supplies can meet operational demand. The results can help estimate the battery storage capacity and backup electricity requirements needed to reduce the risk of production disruptions.
References
Prieska Power Reserve project
Optimized Demand-Side Day-Ahead Generation Scheduling Model for a Wind–Photovoltaic–Energy Storage Hydrogen Production System
Technical evaluation of the flexibility of water electrolysis systems to increase energy flexibility
Optimized Energy Management and Reliability Assessment of RES Based Microgrid
This article was published November 10th, 2026 and the content is current as at the date of publication.
