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The amount of unamortized compensation expenses.

No definition available.

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Weighted average vesting period.

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
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- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
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-URIDate 2025-03-27

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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-URIDate 2025-03-27

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The number of instruments granted in share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
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-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph IG23
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_IG23&doctype=Implementation%20Guidance
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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

The number of other equity instruments (ie other than share options) granted 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 47
-Subparagraph b
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Data Type:	xbrli:decimalItemType
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The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement.

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Data Type:	xbrli:decimalItemType
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Period Type:	duration

The number of share options forfeited in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
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-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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-URIDate 2025-03-27

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

The number of shares authorised.

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 i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B10_a_i&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
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-Paragraph 79
-Subparagraph a
-Clause i
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-URIDate 2025-03-27

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-Subparagraph d
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-URIDate 2025-03-27

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Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=HTOO_EmployeesAndDirectorsMember
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=HTOO_DirectorsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=HTOO_NonExecutiveDirectorsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfShareCapitalAxis=ifrs-full_OrdinarySharesMember
Namespace Prefix:
Data Type:	na
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