SynCons: Are we in StarWar ?

Synchronous Condensers, What is this ?

Do not worry, we are not in a new science-fiction movie !

As the energy transition is speeding up everywhere, integration of renewables remains a challenge for mostly all grid operators.

In fact, in a power system, there are two types of power: active power (measured in watts) and reactive power (measured in volt-amperes reactive, or VAR and only for specialists ;)). Active power is the actual power that performs useful work, such as driving motors or lighting bulbs. Reactive power, on the other hand, is the power required to establish and maintain electric and magnetic fields in the system. It helps voltage regulation and maintaining the power factor.

A synchronous condenser helps to manage reactive power by generating or absorbing it as needed. It is connected to the power grid and operates at a slightly leading or lagging power factor, depending on the system's requirements. By injecting or absorbing reactive power, the synchronous condenser helps to regulate the system voltage, improve power factor, and stabilize the grid.

The device consists of a synchronous machine, typically a three-phase generator, coupled with a prime mover, such as a turbine or an internal combustion engine. It operates in synchronization with the grid and can quickly adjust its output to compensate for fluctuations in reactive power demand.

Synchronous condensers are particularly important in power systems with a significant integration of renewable energy sources, such as wind and solar, for several reasons:

1. Voltage Regulation: Renewable energy sources, especially wind and solar, are intermittent in nature. Their output can vary due to changes in weather conditions. Synchronous condensers help regulate voltage by dynamically adjusting their reactive power output, compensating for fluctuations caused by renewable energy sources. This helps maintain stable voltage levels and ensures the quality of power supplied to consumers.
2. Power Factor Correction: Renewables often have a low power factor. Synchronous condensers can operate at a leading or lagging power factor, compensating for the reactive power imbalance caused by renewables.
3. Grid Stability: Renewables can introduce grid instability due to their intermittent nature. Synchronous condensers provide inertia to the system, which helps stabilize the grid. Inertia refers to the ability of rotating machines to maintain system stability in response to disturbances. Synchronous condensers, with their rotating mass, simulate the behavior of traditional synchronous generators and enhance grid stability.
4. Fault Ride-Through Capability: Renewable energy sources may experience disturbances or faults on the grid, such as voltage sags or faults on transmission lines. Synchronous condensers can provide fault ride-through capability by injecting reactive power into the system during such events. This helps maintain grid stability and prevents cascading failures.

There are alternative technologies and solutions that can provide similar functionalities to synchronous condensers:

1. Static Var Compensators (SVC): SVCs are power electronic devices that can inject or absorb reactive power to regulate voltage and improve power factor. They use thyristor or insulated-gate bipolar transistor (IGBT) technology to quickly respond to changes in system conditions. SVCs are capable of providing dynamic voltage support and reactive power control without the need for mechanical components.
2. Static Synchronous Compensators (STATCOM): STATCOMs are another type of power electronic device used for reactive power compensation. They operate on voltage-source converter (VSC) technology and can rapidly inject or absorb reactive power to stabilize the grid voltage. STATCOMs offer fast response times and can be more flexible in controlling reactive power compared to synchronous condensers.
3. Battery Energy Storage Systems (BESS): Energy storage systems, particularly battery-based systems, can be utilized to provide reactive power support and voltage regulation. By charging or discharging the batteries, they can inject or absorb reactive power to balance the system and mitigate voltage fluctuations. BESSs offer fast response times and can provide additional benefits such as energy time-shifting and grid support during periods of high demand.
4. High Voltage Direct Current (HVDC) Systems: HVDC systems, used for long-distance transmission or interconnecting asynchronous grids, can also provide reactive power support. By controlling the converter stations, HVDC systems can inject or absorb reactive power to stabilize the connected AC grids.

These alternatives to synchronous condensers offer varying advantages and may be suitable for different grid scenarios and requirements. The choice of technology depends on factors such as grid characteristics, system needs, and cost-effectiveness.

In this context, it is clearly expected that the synchronous condenser market will improve within the coming years.

In North America, the United States and Canada have already significant installations of synchronous condensers. The aging infrastructure and retiring conventional power plants contribute to the demand for synchronous condensers in this region.

In Europe, countries such as Germany, the United Kingdom, and Spain have been actively deploying synchronous condensers. These markets have experienced a significant increase in renewable energy capacity, especially wind power, which requires robust grid stability measures. Additionally, the phasing out of conventional power plants and the need for reactive power compensation have further fueled the demand for synchronous condensers in Europe.

In Asia-Pacific, countries like, for instance, Vietnam or Australia will definitively need synchronous condensers in areas with a high concentration of renewable energy generation. In Australia, this is already the case in Robertstown area, 90min drive north from Adelaide where Siemens Energy and the Australia Grid Technologies teams have already implemented for ElectraNet a SynCons station.

Therefore, as the world transitions towards a cleaner and more sustainable energy mix, the synchronous condenser market is expected to experience growth and improvements in the coming years, driven by the need for grid stability and the integration of renewable energy sources.