Stable Power Supply: ECOVE Diversifies Energy Business Portfolio through Power Storage Development

The transformation towards low-carbon energy has become a global trend, as worldwide demand for green power continues to rise. However, renewable power supply faces inherent limitations such as timeliness, intermittence and volatility, which have great impact on the power grid and leads to the instability of power supply. Power auxiliary services such as energy storage system can make full use of power by supplying renewable energy in parallel with conventional electricity, thus cutting fuel consumption and pollution emissions from traditional generation units. ECOVE not only increases the investment and development of solar photovoltaic projects, but also actively develops its energy storage business by investing in the energy storage system in connection with the power auxiliary service of Taiwan Power Company (Taipower), the state utility. That way, ECOVE is contributing to the stability of power grids.

Introducing megawatt energy storage system to ensure safe and stable operation of power system

To create an innovative green energy tech industry, the government in recent years has focused on transforming the energy landscape and building a green energy technology island. ECOVE has long paid attention to such trend and continued to invest in the development, establishment and operation of solar photovoltaic projects. To date, more than 80 projects have come online, with total developed capacity exceeding 126MW. The rise in global demand for renewable energy has brought along the problem of unstable power generation and supply posed by renewable energy. To tackle this issue, installing energy storage system at the end of power grid has become the main solution across the world.

This is why ECOVE has actively invested in the field of energy storage. The company has applied for the establishment of a five megawatt (5MW) energy storage grid-connected feeder, and will accelerate the construction process. As part of the future plan, ECOVE intends to participate in Taipower’s power auxiliary service (frequency modulation backup) through the energy storage system, which can help the power grid quickly stabilize the short-term frequency change of the power system, improve the stability and reliability of power supply, reduce the inconvenience and loss caused by power failure, and take a new step in diversifying its energy business portfolio.

Equipment selection and planning of megawatt energy storage system

ECOVE’s megawatt energy storage system is mainly used for the power system. Since the energy storage system needs to be connected with the power system of Taipower, the selection of system equipment must give priority to safety, stability and reliability.

The main equipment of the energy storage system includes battery energy storage system (BESS), power conversion system (PCS), energy management system (EMS), and high voltage electromechanical equipment.

In terms of battery selection, the mainstream choices are lithium-ion battery and lithium iron phosphate battery. After careful assessment by ECOVE’s expert team, the team decided to choose lithium iron phosphate battery for fear of the explosion risk and difficulty of fire extinguishing associated with lithium-ion battery. As for power regulator, the team chose an equipment with high conversion efficiency (> 98%) and low harmonic distortion (< 3%). The energy management system mainly controls power charging and discharging according to the needs of the power system.

An example of ECOVE’s energy storage project is located in Taiwan’s central industrial zone. This project takes place in an idled fractional land of the owner's plant, so as to maximize land use. Due to noise, landform, and battery weight (35 tons per set) considerations, the battery system was placed inside the site to avoid raising the cost from land improvement. In addition, in order to minimize the interface integration problem during the post installation capacity test period and ensure the quality of the project as scheduled, the whole set of equipment is mainly selected based on the supplier’s actual performance experience of domestic FM auxiliary services and real-time service provision potential. The battery system, on the other hand, adopts safer lithium iron phosphate technology products.

Planning and configuration diagram of ECOVE Solar Energy’s energy storage system project in progress

Energy creation + energy storage for stable power supply

Looking forward to the future, there will be gradually more power applications to reduce the impact of extreme climate and respond to the goals of energy conservation, carbon reduction and net zero carbon emission echoed by the United Nations. ECOVE will actively combine the internal and external resources of its parent company CTCI, master the core technology of energy storage system, and take concrete actions to support the short, medium, and long-term renewable energy plan vigorously promoted by the government in combination with its solar photovoltaic track record, so as to achieve the goal of sustainable energy development, and set a new model of green energy construction for Taiwan's large-scale power industry.