Note 13 - Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) - USD ($)	Dec. 31, 2024	Sep. 30, 2024
Regulatory assets	$ 4,147,799	$ 5,103,910
Noncurrent regulatory assets	4,405,790	4,445,044
Total regulatory assets	8,553,589	9,548,954
WNA [Member]
Regulatory assets	1,419,820	919,375
Regulatory Clause Revenues, under-Recovered [Member]
Regulatory assets	1,350,697	2,690,247
Under-recovery of RNG Revenues [Member]
Regulatory assets	1,286,768	1,331,064
Under-recovery of SAVE Plan Revenues [Member]
Regulatory assets	45,663	107,678
Pension Costs [Member]
Regulatory assets	32,089	42,785
Noncurrent regulatory assets	2,998,881	2,998,881
Other Assets [Member]
Regulatory assets	12,762	12,761
Noncurrent regulatory assets	293,584	304,291
Deferred Gain (Loss) on Early Extinguishment of Debt [Member]
Noncurrent regulatory assets	1,113,325	1,141,872
Total regulatory assets	$ 1,113,325	$ 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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