Renewable Energy/Energy Storage Systems

Energy Storage Systems

A Battery Energy Storage System collects energy from an electricity grid or renewable power sources, such as solar and wind, and stores it using battery storage technology. Then, batteries discharge and release the energy when necessary—during peak demands, power outages, and in a variety of other applications.

Energy Storage Systems

Sara Incorporated in cooperation with Danfoss

Sara Li-ion Battery Pack

Danfoss Industries and Sara Incorporated commissioned a 270 Kw/Hr Battery Energy Storage System, S-Grid, at Danfoss’s India Plant to provide system flexibility while charging it from the 1.2 MW Solar plant installed on the premises.


Danfoss Industries Pvt Ltd. (Subsidiary of the 7 Billion Euros in sales Danfoss Group with its HQ in Denmark) and Sara Incorporated, inaugurated India’s first privately owned and managed grid-scale battery-based energy storage system, S-Grid, in Oragadam, Chennai. The 270 kilowatt-hours (KWh) system, designed and commissioned by Sara Incorporated, will pave the path for the wider adoption of grid-scale energy storage technology across India.


Battery-based energy storage enables electricity to be stored and then delivered within milliseconds, reducing the instability of the electric grid and enabling more energy to be captured and delivered on-demand. India has the ambitious vision of installing 250 GW of renewable energy generation by 2025.


Battery-based energy storage provides the flexibility and agility to better integrate intermittent solar and wind energy resources into India’s electric grid and ensure high-quality power for consumers.


S-Grid, a 270 KW/Hr project, is located at Oragadam, Chennai, and will be charged by the 1.2 MW Solar Plant at Danfoss’s facility. This system is part of the journey at Danfoss to become carbon-free by 2030. Danfoss also proposes to add a charging station to this system to enable a fully green vehicle with no fossil fuel requirement for charging.

Optimized for containerized solutions
Modular design with integrated distributed BMS
Excellent Thermal management
Full control of development and production
Cell Technology LiFePO4
Nominal Cell Voltage 3.2
Nominal Battery Voltage/Min/Max 880/920/1000V
Installed Capacity 270kWh (288 x 100S3P)
Usable Energy at 80% DOD 215 kWh
Usable Energy at 75% DOD 200 kWh
Power Delivery & Charging
Nominal/Max discharging Current (0.5C/1C) 135/270A (Fuse protection at 400A)
Max Charging Current (0.5C) 135A (Two-hour Charge rate)
Expected Cycles @ 70D0D @1C >4000 Cycles (.5C Charge and Discharge)
Expected Cycles @ 80DOD @1C >3000 Cycles (.5C Charge and Discharge)
Efficiency @ C1 +-90%
Temperature Charge -25°C-55°C Discharge -20°C-65°C
Battery Management System (BMS)
Digital Battery Management System Master-Slave topology
CMS (Cell Management System) 12 LiFeP04 per CMU (24xCMU Modules)
Communications Can Bus diagnostics interface
ISOSPI Bus internal comms
CAN bus 2.0 A&B
MCU – Isolated Power Supply 6-35V Power from the main pack – No ups needed
MCU Power Consumption <3.2W @ 12V <20mW @ 12C in sleep mode
CMU- Power Supply Minimum 3 Cells 6-40V
CMU- Power Consumption <0.6W for 12cells (operating) <0.3mW (sleep mode)
Temperature Measurements Cell-Level and CMU level (Total of 288)
Protection 120 + Error messages
Dimensions BESS Module
Width 2200 mm
Depth 530 mm
Height 22300 mm
Weight (without Cells) 300 kg
Weight (with Cells) 2000 kg
EMS & Control Siemens S7 1200
User Communications Can-BUS(Isolated & non-Isolated) Profi Bus, RS232
TCP/IP: Modbus – Profi Net

As per the proposed policy by the Ministry of Power, ESS developers shall be granted Inter-State Transmission System connectivity under General Network Access (GNA) allowing them to sell/ purchase power from any part of the country. The quantum of ESS included with Round-The-Clock (RTC) Renewable Energy shall be counted as Renewable Purchase Obligation (RPO) for storage. Renewable Energy Certificates (RECs) may be issued to ESS. Discoms/ Obligated entities can set up their own storage or procure storage capacity or lease storage space from public or private ESS developers. Any sale of electricity from storage or sale/ lease of storage space may be through open competitive bidding or Power exchange or through tariff fixed u/s 62. The policy proposes that transmission cost for RE shall be waived both at the time of charging the storage as well as at the time of selling the stored RE.

In addition to Battery Energy Storage Systems, we also develop and execute:


We have configured and executed a 1 MW solar-based renewable energy system made of photovoltaic cells that generate power and allow the system to act independently of the main grid, but also integrate and interact with the main grid when desired. A microgrid provides low-cost and efficient green energy independent of the regional electric grid which is useful for remote areas with unstable or congested energy supply, eradicating energy poverty.

Hydrogen-fuelled energy solutions using solar-generated

electric currents to separate water into oxygen and hydrogen, is a complete carbon emission-free process, creating hydrogen power that can be stored and used easily.