Note 13 - Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) - USD ($)	Mar. 31, 2024	Sep. 30, 2023
Regulatory assets	$ 5,005,793	$ 2,854,276
Noncurrent regulatory assets	5,310,937	5,389,445
Total regulatory assets	10,316,730	8,243,721
WNA [Member]
Regulatory assets	3,282,311	414,689
Regulatory Clause Revenues, under-Recovered [Member]
Regulatory assets	0	1,383,340
Under-recovery of RNG Revenues [Member]
Regulatory assets	1,589,211	797,804
Pension Costs [Member]
Regulatory assets	121,509	243,017
Noncurrent regulatory assets	3,786,265	3,786,265
Other Assets [Member]
Regulatory assets	12,762	15,426
Noncurrent regulatory assets	325,707	347,121
Deferred Gain (Loss) on Early Extinguishment of Debt [Member]
Noncurrent regulatory assets	1,198,965	1,256,059
Total regulatory assets	$ 1,198,965	$ 1,256,059

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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