Renewables are at the centre of sustainable energy, and alongside them are battery energy storage systems. One of the cons of renewable energy is instability; solar energy for instance can not be accessible during nighttimes when the sun has set. Battery Energy Storage Systems (BESS) is a technology that stores energy for later use. BESS can store energy during periods of low demand and release it during peak demand, ensuring a steady and reliable energy supply. In this article we will go over important details of BESS Basics, why we need them and what they are composed of. We will also consider some examples of battery energy storage systems.
Why Do We Need BESS?
Enhancing Renewable Integration
Renewable energy sources are intermittent by nature. BESS ensures that the energy generated from these sources can be stored and used whenever needed, thus facilitating higher renewable energy penetration into the grid.
Grid Stability and Reliability
BESS provides crucial support to the grid by balancing supply and demand, thus preventing blackouts and enhancing grid reliability.
Energy Cost Management
By storing energy during off-peak hours and discharging it during peak hours, BESS helps reduce energy costs for consumers and utilities.
Energy Independence
BESS enables communities and businesses to become more energy-independent by storing locally generated energy for later use.
How Does BESS Work?
Charging
During periods of excess energy production (e.g., when the sun is shining brightly or during off-peak electricity hours), BESS absorbs and stores this energy.
Storage
The energy is stored in batteries, which can be of various types such as lithium-ion, lead-acid, or flow batteries. These batteries are designed to store large amounts of energy efficiently.
Discharging
When energy demand is high or renewable sources are not producing (e.g., at night or during calm weather), the stored energy is released to the grid or used directly to meet the demand.
Components of BESS
Batteries
Batteries are the fundamental elements of any BESS, responsible for storing energy. They come in various chemistries, such as lithium-ion, lead-acid, and flow batteries, each with unique characteristics suited to different applications. The efficiency, lifespan, and safety of a BESS largely depend on the type of batteries used.
Battery Management System (BMS)
The Battery Management System (BMS) is a critical component that monitors the performance of the batteries and ensures their optimal operation. It manages the state of charge (SoC) and state of health (SoH) of the batteries, protecting them from overcharging, deep discharging, and overheating. A well-designed BMS enhances the longevity and reliability of the battery system.
Power Conversion System (PCS)
The Power Conversion System (PCS) converts energy between the grid and the BESS. It includes inverters and converters that manage the flow of electricity, enabling the system to charge from the grid or discharge stored energy back into the grid. The PCS plays a vital role in ensuring the efficient and seamless integration of BESS with the electrical grid.
Notable Case Studies on Battery Energy Storage Systems
California’s Moss Landing BESS
California’s Moss Landing BESS is one of the largest battery energy storage installations globally, with a massive 400 megawatt-hours (MWh) capacity. Located in Monterey Bay, this facility is operated by Vistra Energy and began operations in 2020. The Moss Landing BESS helps enhance grid stability, providing peak shaving, and supporting the integration of renewable energy sources.
In 2022, Vistra announced plans to expand the Moss Landing BESS to 1,500 MWh, further solidifying its position as a key asset in California’s energy infrastructure. The expansion will provide additional grid support during periods of high demand and increase the state’s renewable energy capacity.
Hornsdale Power Reserve (Australia)
Hornsdale Power Reserve in South Australia is another prominent FTM utility-scale BESS, with a capacity of 150 megawatts (MW) and 194 megawatt-hours (MWh). This facility, operated by Neoen and featuring Tesla batteries, became operational in 2017. The Hornsdale Power Reserve has improved grid reliability, reduced frequency fluctuations, and provided fast-responding ancillary services.
In 2020, the Hornsdale Power Reserve underwent an expansion, increasing its capacity by 50 MW/64.5 MWh. This upgrade has enhanced its ability to provide frequency control ancillary services (FCAS), further stabilizing the grid and reducing the risk of blackouts. The facility has saved South Australian consumers millions of dollars by reducing the need for expensive peaking power plants.
Tesla’s South Australia Virtual Power Plant
Tesla’s South Australia Virtual Power Plant (VPP) is an innovative project that networks residential solar panels and Powerwall batteries to form a 250-megawatt-hour (MWh) virtual power plant. This initiative, launched in 2018, aims to connect up to 50,000 homes, providing them with solar power and battery storage systems. The aggregated capacity supports grid stability and provides backup power during outages.
As of 2023, Tesla’s South Australia VPP has connected over 4,000 homes, with expansion plans. The project has demonstrated significant benefits, including a 30% reduction in energy bills for participating households and improved grid reliability during peak demand periods. The VPP also enhances the integration of renewable energy by storing excess solar power generated during the day and discharging it during the evening.
Amazon’s BESS at Fulfilment Centres
Amazon has implemented Battery Energy Storage Systems at several fulfilment centres to optimize energy consumption, reduce operational costs, and enhance grid resilience. These BESS installations are part of Amazon’s broader sustainability initiatives to reduce the company’s carbon footprint and improve energy efficiency.
In 2022, Amazon reported the deployment of BESS at more than 10 fulfilment centres across the United States and Europe. These systems have helped Amazon manage energy use more effectively by shifting consumption away from peak periods, thus lowering energy costs and reducing strain on the grid. Additionally, the BESS installations provide critical backup power, ensuring operational continuity during grid outages.
The Future of Energy Storage
As we move towards a more sustainable and resilient energy system, the role of BESS cannot be overstated. As manufacturing scales up and technology advances, the cost of battery storage will continue to decline. Improvement in battery chemistry and design will improve the efficiency and flexibility of BESS.
Research and development efforts such as solid-state batteries promise to enhance performance and longevity compared to current lithium-ion batteries. BESS will become more integrated with smart grid technologies allowing for real-time monitoring, optimization and remote management.
