Note 13 - Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) - USD ($)	Jun. 30, 2025	Sep. 30, 2024
Regulatory assets	$ 1,609,701	$ 5,103,910
Noncurrent regulatory assets	4,327,281	4,445,044
Total regulatory assets	5,936,982	9,548,954
WNA [Member]
Regulatory assets	414,812	919,375
Regulatory Clause Revenues, under-Recovered [Member]
Regulatory assets	0	2,690,247
Under-recovery of RNG Revenues [Member]
Regulatory assets	1,068,795	1,331,064
Under-recovery of SAVE Plan Revenues [Member]
Regulatory assets	102,635	107,678
Pension Costs [Member]
Regulatory assets	10,697	42,785
Noncurrent regulatory assets	2,998,881	2,998,881
Other Assets [Member]
Regulatory assets	12,762	12,761
Noncurrent regulatory assets	272,169	304,291
Deferred Gain (Loss) on Early Extinguishment of Debt [Member]
Noncurrent regulatory assets	1,056,231	1,141,872
Total regulatory assets	$ 1,056,231	$ 1,141,872

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

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