Power Plant Controllers in Grid-tied Solar Plants

Camille Petit

Discover in this article the advantages of power plant controllers in grid-tied solar plants. But first, let’s focus on the definition and market overview of grid-tied solar plants.

What is a grid-tied power plant?

Definition of grid-tied solar plant

A grid-tied power plant is a solar power plant which generates and feeds electricity into the national grid. In many countries, the national power grid has remained largely unchained. With the influx of cleaner energy through solar power plants, it must now be retrofitted to handle the huge surge in renewable energy.

Overview of the grid-tied solar plant market 

Technology advancements in the solar energy sector mingled with the ever-increasing demand and awareness of green-energy solutions has made solar power generation grow tenfold. 

Nowadays, solar energy is being harnessed on large scales. According to the IEA, solar PV electricity generation is increased by 145 TWh in 2021, almost 18% in comparison with 2020, to approach 1,000 TWh; among it utility-scale PV installations account for 66% of the total installed PV capacity.

Source: IEA, Solar PV net capacity additions by application segment, 2017-2022

The challenge of regulation for grid-tied solar plants

With more and more solar power plants being integrated into national grids, a challenge comes up for the national grid regulators. They need to integrate intermittent generation units into the main grid, while maintaining its stability. 

Indeed, it becomes increasingly difficult for them to have a smooth commissioning into the main grid. Resultantly, the regulators are forced to define and fix criteria and requirements, defined as grid code, for the solar power plant operators before they can inject power into the national grid.

Even if these rules vary a lot between countries, essential functions need to be handled whenever a solar power plant is integrated into the grid, such as: 

  • coupling/decoupling; 
  • reactive power regulation;
  • voltage/frequency regulation. 
     

For grid-tied power plants, it has now become a necessity to use solutions based on Power Plant Controllers because of the ease they offer in running the plant. 


Advantages of power plant controllers in grid-tied solar plants

  • Complying with grid codes 
  • Increasing reliability 
  • Facilitating remote maintenance 
  • Connecting with spot market

Complying with grid codes

Primarly, power plant controller in grid-tied power plant will help comply with grid codes.

Regulatory authorities have defined some set points which are known as grid codes. Most good quality PPCs support these national and international grid codes for easy integration into the power plant model. Compliance to these grid codes result in regulation-compliant injection of power into the national grid.

Increasing reliability

Secondly, power Plant Controllers or PPC devices prove to be very beneficial to increase reliability. Power Plant Controllers help in controlling and regulating power running through the networked inverters, and other equipment along with  a solar PV plant. The operators can easily control the different parameters to bring them to the set points defined by the regulator so that they can inject power into the main grid. 

Site operators can either directly communicate these set-points to the PPC or can integrate SCADA solutions to automatically determine and control the parameters.

Facilitating remote maintenance

Additionaly, power plant controllers in grid-tied solar plants are an effective solution to control the behavior and the functioning of a solar power plant and enhance its production levels, revenue, regulation compliance and grid stability. 

Other than the regulatory part, PPC devices also offer the added benefit of remote controlling and troubleshooting actions to assist the maintenance team of the plant. The monitoring is done via RTU, weathers stations, inverters, and junction boxes, among others, to facilitate this remote maintenance on site.

Connecting with spot market

Finally, with the recent increase in the energy price, selling on the spot market becomes more and more advantageous for installers. It is favorable to generate more revenue. A power plant controller can help them to integrate their installations with aggregators, who sell the defined energy production on the spot market. 

Indeed, the data collected by controllers, such as Elum’s PPC, will allow aggregators to leverage data knowledge to create their risk models and predict energy flows in advance.  

Moreover, in case of excessive production and when the spot price turns negative, a power plant controller will send an order of decoupling and temporarily cut the installation from the grid to avoid penalties. 

Elum’s power plant controllers for grid-tied solar plant

Elum Energy offers a range of Power Plant Controllers offering different features which are suited for standard to complex requirements on a solar PV plant. Thus, power plant operators can achieve modularity and scalability through the use of Elum Energy’s products.It allow them to attain flexibility in order to meet the high diversity of grid connection requirements in the different countries Elum operates in. 

Elum’s power plant controllers for grid-tied solar plants have a wide range of compatibility with different solar equipment and also gives its users a user-centered user interface along with integrated data collection functions.