v3.25.1

Cover	May 28, 2025
Document Type	8-K
Amendment Flag	false
Document Period End Date	May 28, 2025
Entity File Number	001-40209
Entity Registrant Name	Heliogen, Inc.
Entity Central Index Key	0001840292
Entity Tax Identification Number	85-4204953
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	130 West Union Street
Entity Address, City or Town	Pasadena
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	91103
City Area Code	626
Local Phone Number	720-4530
Written Communications	true
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	true
Common Stock, par value $0.0001 par value per share
Title of 12(b) Security	Common Stock, par value $0.0001 par value per share
Trading Symbol	HLGN
Warrants, each 35 warrants exercisable for one share of common stock at an exercise price of $402.50 per share
Title of 12(b) Security	Warrants, each 35 warrants exercisable for one share of common stock at an exercise price of $402.50 per share
Trading Symbol	HLGNW
Preferred Share Purchase Rights
Title of 12(b) Security	Preferred Share Purchase Rights

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Heliogen, Inc. 8-K