What is ESS?
ESS Inc is a clean energy technology firm specializing in the design and manufacture of long-duration energy storage systems. Utilizing iron flow battery technology, the company provides a sustainable, safe, and reliable alternative to traditional lithium-ion solutions. By employing abundant materials such as iron, salt, and water, ESS Inc offers a scalable platform that supports utilities, industrial operations, and commercial users in managing excess renewable energy. Their systems are engineered to enhance grid stability and ensure a continuous power supply, positioning the company as a key player in the infrastructure required for a decarbonized energy future.
How much funding has ESS raised?
ESS has raised a total of $88.3M across 10 funding rounds:
Unspecified
$493K
Series A
$3.2M
Series B
$13M
Series C
$30M
Debt
$350K
Private Equity
$23M
Unspecified
$17M
Debt
$900K
Unspecified (2013): $493K supported by NYSERDA
Series A (2015): $3.2M featuring Pangaea Ventures and Element 8
Series B (2017): $13M backed by BASF, InfraPartners Management, Cycle Capital Management, and Panagea Ventures
Series C (2019): $30M with participation from Softbank Group, PTT Global Chemical, Breakthrough Energy, and Evergy Ventures
Debt (2020): $350K led by PPP
Private Equity (2024): $23M, investors not publicly disclosed
Unspecified (2024): $17M featuring Queensland Government
Debt (2025): $900K, investors not publicly disclosed
Key Investors in ESS
Pangaea Ventures
A leading venture capital firm specializing in hard tech, focusing on investments in start-ups that utilize advancements in materials and chemistry to tackle global sustainability challenges.
BASF
A globally recognized leader in the chemical industry committed to innovation and sustainability, providing high-performance solutions across diverse industrial sectors.
Cycle Capital Management
A venture capital firm founded in 2009 that focuses on building innovative clean technology companies globally through a platform of investment funds and accelerators.
What's next for ESS?
With the latest capital injection, ESS Inc is well-positioned to accelerate its manufacturing throughput and expand its market footprint. The strategic focus will likely shift toward optimizing supply chain efficiencies and deepening partnerships with utility providers to integrate their storage platforms into national grids. As the demand for energy storage grows in tandem with renewable energy adoption, the company's ability to deliver cost-effective, environmentally friendly solutions will be central to its long-term growth strategy. Future milestones will likely involve scaling production capacity to meet international demand and further refining the performance metrics of their iron flow technology to maintain a competitive edge in the energy storage market.
See full ESS company page
