F
Fourth Power
Energy · Cambridge, United States · Founded 2021
A thermal battery energy storage company MoreLess
Fourth Power, accessible at gofourth.com, is a pioneering startup focused on climate change mitigation through innovative energy storage solutions. The company has developed a unique thermal battery system that harnesses excess wind and solar energy, making it cost-competitive with traditional fossil fuels. This technology is designed to meet the needs of utility companies and energy regulators worldwide.
The core of Fourth Power's technology lies in its thermal battery, which operates at extremely high temperatures—almost half the temperature of the sun. This high power density allows the system to store and release energy efficiently. The battery's subsystems are housed separately within an argon environment, which makes the system safe from fire risks and chemical degradation. This modular design also allows energy and power to be scaled independently, providing flexibility and efficiency.
Fourth Power primarily serves utility companies and energy regulators who are looking for cost-effective, reliable, and scalable renewable energy storage solutions. The company operates in the renewable energy market, specifically focusing on energy storage technologies.
The business model of Fourth Power revolves around the development, manufacturing, and sale of its thermal battery systems. The company generates revenue by selling these systems to utility companies and other large-scale energy providers. Additionally, Fourth Power may engage in partnerships and collaborations with governmental and non-governmental organizations to further its reach and impact.
In 2023, Arvin, who has extensive expertise in energy markets and has held leadership positions with Advanced Energy Economy and the U.S. EPA, joined as CEO. Under his leadership, Fourth Power aims to make renewable energy the most cost-effective and accessible source of power generation through its advanced thermal storage technology.
Keywords: Thermal Battery, Renewable Energy, Energy Storage, Utility Companies, High Power Density, Cost-Competitive, Climate Change Mitigation, Modular Design, Safe Energy Storage, Scalable Solutions.
Company overview
Fourth Power company information
The essential company record, classifications and operating signals in one place.
- Status
- Operational
- Founded
- 2021
- Headquarters
- Cambridge, United States
- Employees
- 35
- Open positions
- 1
- Dealroom signal
- 92.1
Valuation & funding
Fourth Power funding history
Company financing events and reported valuations.
| Deal type | Date | Amount | Valuation | Investors | Source |
|---|---|---|---|---|---|
| SERIES A✓Equity / VC | Sep 2025 | $20M | $80M | DCVC · Breakthrough Energy Ventures · Munich Re Ventures | ↗ |
| SERIES A✓Equity / VC | Dec 2023 | $19M | $76M | The Black Venture Capital Consortium · DCVC · Breakthrough Energy Ventures | ↗ |
| SPINOUT✓Other financing | Jan 2021 | $0 | — | Massachusetts Institute of Technology | — |
Financials
Workforce over time
Available workforce history. Financial fields without reported data are omitted.
| Year | Employees |
|---|---|
| 2026 | 36 |
| 2025 | 26 |
| 2024 | 18 |
| 2023 | 10 |
Growth signals
Fourth Power website traffic
Latest recorded traffic for Fourth Power is 4.7K monthly website visits, down 28.8% over the last three months. Fourth Power's team grew 34.6% over the past year.
Hiring
Open positions at Fourth Power
Current openings linked to this company in Dealroom.
Comparisons
Fourth Power compared with similar companies
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Talent graph
Fourth Power's talent
Source: Dealroom Talent Intelligence.
Global footprint
Where Fourth Power has talent and traffic
team presence
In the news
Latest news about Fourth Power
Recent press, funding announcements, and product moves mentioning Fourth Power — open to read from the original sources.
Market sentiment
What the market is saying about Fourth Power
An AI-synthesized read of the highest-engagement posts about Fourth Power on X over the past 7 days. We rank by likes & retweets, ignore corporate channels, and surface the themes that broke out from real people.
Reading the room on X — pulling top posts and synthesizing themes…
Source: X recent search ranked by engagement (likes + retweets) · Synthesis by Claude · Cached for 1 hour
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