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Number of shares issued value.

No definition available.

Name:	HTOO_NumberOfSharesIssuedValue
Namespace Prefix:	HTOO_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Reverse share split.

No definition available.

Name:	HTOO_ReverseShareSplit
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Balance Type:	na
Period Type:	duration

Share based compensation arrangement by share based payment equity instruments options non vested number.

No definition available.

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Data Type:	xbrli:sharesItemType
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Warrants outstanding term.

No definition available.

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The potential dilutive effect on the weighted average number of ordinary shares that relate to the assumed exercise of the entity's share options.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 33
-IssueDate 2025-01-01
-Paragraph 70
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=33&code=ifrs-tx-2025-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2025-03-27

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Period Type:	duration

The increase (decrease) in equity resulting from share-based payment transactions. [Refer: Equity]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 106
-Subparagraph d
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_106_d_iii&doctype=Standard
-URIDate 2025-03-27

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45&doctype=Standard
-URIDate 2025-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

The number of shares issued by the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 106
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_106_d&doctype=Standard
-URIDate 2025-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The nominal value per share.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph B10
-Subparagraph a
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B10_a_iii&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 160
-Subparagraph a
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_160_a_iii&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 79
-Subparagraph a
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_79_a_iii&doctype=Standard
-URIDate 2025-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:perShareItemType
Balance Type:	na
Period Type:	instant

The weighted average exercise price of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:perShareItemType
Balance Type:	na
Period Type:	instant

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Namespace Prefix:
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Name:	ifrs-full_CounterpartiesAxis=HTOO_HAndPAdvisoryLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_SupplierFinanceArrangementsAxis=HTOO_MineralAndElementAdvisoryAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfShareCapitalAxis=HTOO_ClassAOrdinarySharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	HTOO_TypesOfArrangementAxis=HTOO_MineralAndElementAdvisoryAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_TypesOfContractsAxis=HTOO_MineralAndElementAdvisoryAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ClassesOfShareCapitalAxis=HTOO_ClassAOrdinarySharesOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ClassesOfShareCapitalAxis=HTOO_ClassAOrdinarySharesTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ClassesOfShareCapitalAxis=HTOO_ClassAOrdinarySharesThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Data Type:	na
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