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Fourth Power

Fourth Power

Private
Cambridge, MassachusettsEnergy & Sustainabilityhttps://gofourth.com/

Last Round

Series A

Extension

Sep 16, 2025

Total Funding Raised

$44.11M

Company Overview

Fourth Power is a clean energy company that develops utility-scale thermal battery storage solutions to capture excess wind and solar energy for on-demand grid dispatch.

Sector

Energy & Sustainability

Verticals

Energy Storage, Renewable Energy, Smart Grid

Business Model

B2B

Customer Profile

Hardware Sales

AI Layer

Non-AI

Keywords

thermal energy storagelong-duration energy storageLDESthermal batterymolten tinthermophotovoltaicsTPVgrid-scale storageutility-scale storagegrid stabilityrenewable energy storagenon-lithium storagesci-fi batteriesenergy infrastructure

Historical Pricing

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Caplight Momentum Score

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Fourth Power Comparables

Compare Fourth Power with similar companies based on industry and business-model similarity.

Fourth Power comparables — related companies by embedding similarity
CompanySimilarityMarket Cap
Malta Inc
81%
Ambri
78%
MGA Thermal
77%

Fourth Power Funding Rounds

Historical fundraising activity

Data table
RoundDateAmount RaisedValuationInvestorsSources
Series A ExtensionSep 16, 2025
Series ADec 12, 2023
GrantFeb 27, 2023
GrantDec 18, 2018
GrantNov 28, 2012

Key People

Founding team and executive leadership

Asegun Henry

Founder CTO

Founding Team

Fourth Power Investors

Notable investors and investment history

Fourth Power investors
InvestorRounds
Munich Re VenturesSeries A Extension
Breakthrough Energy VenturesSeries A, Series A Extension
BVCCSeries A
Department of EnergyGrant
DCVC (Data Collective)Series A Extension, Series A

Market signals

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  • Feb 27, 2023

    $10K grant received from the Department of Energy.

Fourth Power Filings

SEC and related filings with document metadata.

Data table
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Fourth Power Filings

SEC and related filings with document metadata.

Frequently Asked Questions

Common questions about Fourth Power's valuation, stock price, and market status.

Firmographic Details

HeadquartersCambridge, Massachusetts
Employee Range33
Year Founded2021
Last FundingSep 16, 2025

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