The rapid advancement of both large and small intermittent generation capacities has thrust the energy sector into uncharted territory. As we navigate this new landscape, it often feels like we are groping in the dark, searching for answers to pressing challenges. However, through informed dialogue, we can illuminate potential solutions to the imbalances that arise within our modern energy systems. We had the chance to have such a conversation with our recent guest at Energynomics Talks, Răzvan Rădulescu, CEO Software Media WEBUS 4 ENERGY. He advanced several possible solutions. One of them is related to using energy management systems. Another lies in better integrating consumers and producers. For both of them, technological capabilities are at the forefront. However, a paradigm shift in market and commercial behaviors, to foster a more integrated and cooperative energy ecosystem, is also paramount.
One significant challenge is the daily imbalances and associated costs that photovoltaic (PV) plants face. The fluctuating nature of solar energy means that production can vary dramatically during the day, leading to inconsistencies in supply and potential financial losses.
Sources of unpredictability
There are four types of imbalances, in two directions, i.e. consumers and producers, each category being, sometimes for very short periods of time, in a situation of demanding more or less than forecasted.
At producer level, we have the unpredictability that comes with the weather. “From one day to the next, the forecast tells us how strong the sun will be, unless there are clouds. Weather fronts are predictable at the 2-3 day level. The [clouds] that are unpredictable are the ones that occur locally in the short term and spoil the forecast at the hourly level. In these situations, balancing means replacing scheduled and sold generation with other energy sources.
“In our experience, in the photovoltaic parks we work with, production variations of 30–40% can occur at intervals of 5 minutes,” said Răzan Rădulescu.
A second source of unpredictability comes from consumers, who may consume more or less than anticipated, requiring suppliers to find solutions to balance supply and demand. “The system goes into imbalance until someone comes along and turns on the turbines to put power back” into the system.
Robust energy management systems are crucial
PV power generation is the most viable financial solution. “The investment as such is the smallest, easiest to implement and with minimal environmental impact,” says Răzvan Rădulescu. Moreover, photovoltaics do not produce imbalances all day long, but mainly in the middle of the day. “When we want to balance the grid, we need energy, and the solution is photovoltaics, together with various storage and market solutions.”
For short-term imbalances, Răzvan Rădulescu puts forward two types of answers: digitalization and commercial solutions. For this, robust energy management systems are crucial. Such systems can optimize the scheduling and dispatch of energy, ensuring that PV plants operate efficiently and cost-effectively despite their inherent variability.
Regarding the commercial approach, “one should not try to sell everything they anticipate to be able to produce based on the forecast”. Răzvan Rădulescu recommends limiting volumes sold into the market below forecasted capacity to eliminate surplus imbalances. To avoid negative imbalance situations, one solution is to install storage equipment “The best option would be between 10% and 30% of the installed capacity”, says the Energynomics Talks guest. Or perhaps another, smaller share of the capacity anticipated to be delivered to the grid, taking into account the second solution. This is to deliver for intra-day balancing the volumes that the operator has not sold precisely to maintain a buffer.
The imbalances typically observed are less than a hundred MW at certain times of day, “which is not very much”, says Răzvan Rădulescu. Extending more sophisticated behavior on the part of PV plant operators would solve much of the short-term imbalance problems, he argues.
Automated systems reduce the amount of energy needed for balancing. “We have equipment that connects to the park remotely and can talk to the inverters to control the output according to need. […] The PV park operator has to take the necessary measures not to disturb the grid. […] They do not realize that such solutions exist and can be implemented”, insisted Răzvan Rădulescu.
What is WEBUS 4 ENERGY
Software Media is a team coming from the telecommunications area, which has developed the no-code platform WEBUS 4 ENERGY, based on which it can implement “a different and customized solution for each new customer”. “We do digitalization without programming,” says Răzvan Rădulescu. Photovoltaic parks are different from each other not only from a technical perspective, but also from a business behavior perspective, so everything has to be calibrated for each situation. “We have hardware of our own production; we have a mini-server located in the park and a central server connecting with the markets and visualizing the plant from all the necessary perspectives. […] Our solution is already being tested in the Romanian market, including with more than 20 aggregated generators and about 10 stand-alone generators, with an average installed capacity of 3-5 MW per park.”
