When businesses consider investing in Battery Energy Storage Systems (BESS), the focus is often on the immediate benefits: saving on electricity costs, providing backup power, or optimizing solar power systems. However, the value of BESS goes far beyond that. At a large scale, BESS is a critical asset, capable of providing essential “ancillary services,” acting as an unsung hero to ensure the stability and security of the entire national power system.
This article will raise your level of understanding, explaining how BESS is not only a solution for businesses but also an indispensable factor in Vietnam's energy transition era.
1. What are “Ancillary Services”?
Imagine the national grid as a giant and complex machine. In order for this machine to operate smoothly, in addition to producing electricity (its main service), it needs a lot of “logistics” and “maintenance” activities to continuously keep all parameters in balance. These activities are called ancillary services.
These are technical services necessary to support the transmission of electricity from power plants to consumers, ensuring the stable and reliable operation of the power system.
2. The Role of BESS in Providing Ancillary Services
With the ability to charge and discharge energy almost instantaneously, BESS is an extremely flexible and efficient tool for providing important ancillary services that are difficult to meet well with conventional power plants.
a. Frequency Regulation
- Importance: The frequency of the power grid in Vietnam must always be maintained at a stable 50Hz. Any difference between supply (generation) and demand (consumption) will cause this frequency to fluctuate, affecting the quality of electricity and possibly damaging sensitive equipment.
- Role of BESS: BESS acts as a super-sensitive “governor”. When it detects that the grid frequency starts to increase (oversupply), it will immediately absorb energy (charge). Conversely, when the frequency decreases (supply shortage), it will immediately inject energy into the grid (discharge). This ability to react in milliseconds helps keep the grid frequency stable, ensuring power quality for the entire system.
b. Voltage Regulation
- Importance: Similar to frequency, voltage also needs to be maintained within acceptable limits. Too high or too low voltage can damage electrical equipment.
- Role of BESS: In downstream areas or areas with many renewable energy plants, voltage can fluctuate greatly. BESS can be used to absorb or supply reactive power, acting as a giant “voltage stabilizer”, helping to maintain voltage within a safe and stable range for the area.
c. Load Shifting
- Business perspective: This is a strategy of charging during off-peak hours and discharging during peak hours to save costs.
- Grid view: This is an extremely valuable service. By reducing peak demand from the grid, BESS systems help to “flatten” the national load profile. This reduces the stress and risk of overloading the transmission line system and substations, contributing to reduced losses and improved overall grid efficiency.
3. Vietnam Context: Why Are Ancillary Services Becoming Urgent?
The boom of renewable energy sources such as solar and wind power is a positive signal for Vietnam's sustainable development goals. However, these energy sources are highly variable (only generating electricity when there is sun and wind), creating major challenges for grid stability.
As the share of renewable energy in the system increases, the need for ancillary services to “smooth” these fluctuations will become extremely urgent. BESS is the most suitable and effective technology to solve this problem.
Recognizing this strategic role, Power Master Plan 8 has set very ambitious goals for the development of energy storage systems. This not only opens up a huge potential market but also shows that future BESS investors may have the opportunity to participate in the ancillary service market, creating additional revenue streams from their own systems.
Conclude
A BESS is more than just an energy solution for a single factory or building. It is a key component of a smart, modern and sustainable grid. By providing essential ancillary services, BESS enables deeper integration of renewable energy sources, increased reliability and energy security for the entire country.
For investors, understanding this macro role of BESS will open up a new vision: owning a BESS system is not only about optimizing costs for oneself, but also about holding a strategic asset, ready to contribute to and benefit from the development of the future energy market.
