BESS Energy Storage System for Low and Medium Voltage and the Need for Decarbonisation of the Grid

To successfully achieve the next step of the energy transition, additional grid supporting components and markets are needed, to properly balance the grid while less conventional power plants are available. Smart energy consumption, cost-cutting, resilience, resource-saving, environmental efficiency—this is not a complete list of benefits offered by a battery energy storage system (BESS). With a wide range of power and storage capacity, BESSs vary from small-sized household devices to large-scale systems used for utilities and industrial applications. Battery Energy Storage Systems (“BESS”) are infrastructure technologies that can store large amounts of energy for an electricity grid. BESS projects are currently very profitable. Should the need arise, the electrochemical energy is discharged from the battery and supplied to homes, electric vehicles, industrial and commercial facilities. In emerging countries such as India and SEA, unlevered investment payback periods for BESS projects are 3 – 5 years.

Homeowners with rooftop solar may have come across home energy batteries (the size of a large appliance). These batteries store energy to power homes in the evening (called “Energy Shifting”) or during brownouts.

Although various flexibility options are considered for these tasks, battery energy storage systems (BESS) are currently one of the most promising candidates to fill this gap. Technically, these systems are characterized by the fact that they can provide a large amount of energy very quickly and with high efficiencies. Meanwhile, safety, reliability, and lifetime have reached a considerable level and, at the same time, costs have dropped significantly We are in a stage in which storage systems are increasingly being implemented to take over tasks that would not have been economically feasible a short time ago. Therefore, many investors are currently ready to invest in these applications and are looking for new areas in which storage systems can be prosperous business opportunity. Unfortunately, regulatory hurdles still exist in many countries, because of the difficulties to identify the role of energy storage within the traditional power system structure of generation, transmission/distribution, and consumption.

Overview of the most important applications that can be realized with the help of BESS based on the categories of the European Association for Storage of Energy

This view on the selected applications has followed the steps to first introduce them, investigate on location specific criteria, and finally provide insights on market size as well as suitable technologies.

Self-consumption
The main use-case for stationary battery storage until at least 2030 is going to be related to residential and commercial and industrial (C&I) storage systems providing customer energy time-shift for increased self-sufficiency or for reducing peak demand charges. This segment is expected to achieve more than 100 GWh by 2030.

Photovoltaics (PV) self-consumption (SC) and the adoption of BESS is currently allowed in the vast majority of the world’s countries (with defined technical connection rules), but there are many and very different approaches to its economic regulations.

Storage systems, from a technical point of view, are more efficient when placed as district storage units within the low-voltage (LV) distribution grid, enabling more PV penetration at household level, and, e.g., enabling more effective grid services such as voltage control.

STORAGE APPLICATIONS AT THE DIFFERENT LEVELS OF THE ELECTRICAL SYSTEM
1. Generation level: Arbitrage, capacity firming, curtailment reductions
2. Transmission level: frequency and voltage control, investment deferral, curtailment reduction, black starting
3. Distribution level: voltage control, capacity support, curtailment reduction
4. Customer level: peak shaving, time of use cost management, off-grid supply
 

Storage enables higher penetration of renewables into a grid
Similarly, BESS are large-scale projects that can be used to shift energy consumption from the daytime when it is generated to the night time when it is also needed. The more an electricity grid (of a country/island) relies on intermittent renewable energy, the more important the role BESS plays in providing stability. This is because BESS provides much more services than just supplying energy during periods when there is low/no generation.

Aside from Bulk Energy Services (such as Energy Shifting), BESS is also utilized for use-cases known as Ancillary Services:
1. Operating Reserves — BESS can be used to provide back-up power to the whole grid in the event of plant outages or natural disasters
2. Frequency regulation — BESS can be used to smooth energy supply/demand imbalances that change the frequency (hertz) of electricity moving through transmission lines
3. Inertia — BESS can be used to harmonize the frequency of the grid in certain difficult-to-access locations
4. Voltage Control — Frequency regulation for back-up generators
5. Black Start — Batteries can be used to jump-start natural gas plants Ancillary Services are necessary to stabilize electricity grids (ie prevent blackouts and brownouts), particularly those in emerging markets where grid infrastructure tends to be less maintained or overburdened.

Additionally, BESS can also be used to defer investments in augmenting transmission & distribution lines that are no longer adequate to support the energy consumption of homes and businesses in a specific area. While building new transmission lines can take years to plan, approve, acquire the right-of-way, and construct, a BESS can be developed on a single piece of land in 6 months.

Microgrids
A BESS is an essential part of microgrids—distributed power networks that can be connected to the utility grid or totally independent. Standalone microgrids located in remote regions can rely on battery storage systems integrated with intermittent renewable energy sources. Such solutions enable smooth power generation and help avoid heavy expenses and air pollution associated with diesel generators.

BESSs find wide use in different industries and application areas. For example, front-of-the-meter (FTM) applications comprise battery storage systems in electric power systems, such as utility-scale generation and energy storage facilities as well as transmission and distribution lines. Behind-the-meter (BTM) applications embrace transportation, including electric vehicles and marine systems, residential, commercial, and industrial battery storage solutions.

Front-of-the-meter applications
Battery energy storage systems can contribute heavily to the operation and maintenance of utility-scale facilities and equipment. A BESS can offer reserve capacity and blackstart services, provide voltage and frequency stability, and save money through deferred maintenance. FTM BESS applications include:
• Utility grids
• Substations
• Transmission and distribution lines
• Power stations
 

Behind-the-meter applications
BTM systems can supply power to consumers, bypassing an electricity grid. Along with green energy sources, a BESS can ceaselessly support standalone power systems or microgrids. Manufacturers can use battery storage for power backup to avoid downtime at production facilities. By using BESSs, companies and families can significantly reduce electricity tariffs with energy time-shifting. BTM battery energy storage systems can be found in:
• Industrial and manufacturing facilities
• Businesses
• Households
• Electric vehicles
• Marine systems

BESS around the Globe
Each use-case and geography can be more appropriately-served –resource-efficient, effective — by different BESS technologies. However, 80% of global BESS installed storage capacity uses variants of Lithium-ion technologies.

The global capacity installed this year alone (29.5 GWh in 2021) was more than that installed in the previous 15 years combined (Total of 54.4GWh). Over the next decade, an additional ~$262Bn will be invested in new storage projects. This is because of the high project returns in countries with a strong enabling regulatory environment.

LV & MV Li-Ion BESS offer solutions that can be very attractive to mitigate these ongoing costs, and they offer a greater flexibility to distribute the backup power across a facility as the assignment evolves and also helps in evolving new and emerging models.

- A.K. Shukla, Founder and MD, Sanvaru Technology Ltd