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v3.25.3

Summary of Significant Accounting Policies (Tables) | 6 Months Ended
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Oct. 31, 2025
Accounting Policies [Abstract] |
Schedule of Cash, Cash Equivalents and Restricted Cash | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that total to the same amounts shown in the Consolidated Statements of Cash Flows. Schedule of Cash, Cash Equivalents and Restricted Cash
|  | October 31, 2025 |  |  | April 30, 2025 |
|  | (in thousands) |
Cash and cash equivalents |  | $ | 11,659 |  |  | $ | 6,715 |
Restricted cash- long term |  |  | 154 |  |  |  | 154 |
Cash, cash equivalents, restricted cash and restricted cash equivalents |  | $ | 11,813 |  |  | $ | 6,869 |
Schedule of Property and Equipment Estimated Useful Life | Schedule of Property and Equipment Estimated Useful Life
Description |  | Estimated depreciable life
Equipment |  | 5-7 years
Computer equipment & software |  | 3 years
Office furniture & fixtures |  | 3-7 years
Leasehold improvements |  | Shorter of the estimated useful life or lease term
Leased Power Buoy assets |  | 10 years
Leased WAM-V assets |  | 10 years
Schedule of Revenue Recognized Under ASC 606 and ASC 842 | The table below represents the total revenue recognized under ASC 606 and ASC 842 for the three and six months ended October 31, 2025 and 2024. Schedule of Revenue Recognized Under ASC 606 and ASC 842
|  | Three months ended October 31, 2025 |  |  | Three months ended October 31, 2024 |
|  | ASC 606 |  |  | ASC 842 |  |  | Total |  |  | ASC 606 |  |  | ASC 842 |  |  | Total |
|  | (in thousands) |  |  | (in thousands) |
Product Line: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
WAM-V |  | $ | 101 |  |  | $ | 68 |  |  | $ | 169 |  |  | $ | 2,182 |  |  | $ | 65 |  |  | $ | 2,247 |
Buoy |  |  | 255 |  |  |  | — |  |  |  | 255 |  |  |  | 171 |  |  |  | — |  |  |  | 171 |
Services |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total |  | $ | 356 |  |  | $ | 68 |  |  | $ | 424 |  |  | $ | 2,353 |  |  | $ | 65 |  |  | $ | 2,418 |
Region: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
North and South America |  | $ | 137 |  |  | $ | — |  |  | $ | 137 |  |  | $ | 1,491 |  |  | $ | — |  |  | $ | 1,491 |
EMEA |  |  | 43 |  |  |  | 68 |  |  |  | 111 |  |  |  | 860 |  |  |  | 65 |  |  |  | 925 |
Asia and Australia |  |  | 176 |  |  |  | — |  |  |  | 176 |  |  |  | 2 |  |  |  | — |  |  |  | 2 |
Total |  | $ | 356 |  |  | $ | 68 |  |  | $ | 424 |  |  | $ | 2,353 |  |  | $ | 65 |  |  | $ | 2,418 |
Revenue |  | $ | 356 |  |  | $ | 68 |  |  | $ | 424 |  |  | $ | 2,353 |  |  | $ | 65 |  |  | $ | 2,418 |
|  | Six months ended October 31, 2025 |  |  | Six months ended October 31, 2024 |
|  | ASC 606 |  |  | ASC 842 |  |  | Total |  |  | ASC 606 |  |  | ASC 842 |  |  | Total |
|  | (in thousands) |  |  | (in thousands) |
Product Line: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
WAM-V |  | $ | 1,139 |  |  | $ | 135 |  |  | $ | 1,274 |  |  | $ | 3,416 |  |  | $ | 132 |  |  | $ | 3,548 |
Buoy |  |  | 321 |  |  |  | — |  |  |  | 321 |  |  |  | 171 |  |  |  | — |  |  |  | 171 |
Services |  |  | 11 |  |  |  | — |  |  |  | 11 |  |  |  | — |  |  |  | — |  |  |  | — |
Total |  | $ | 1,471 |  |  | $ | 135 |  |  | $ | 1,606 |  |  | $ | 3,587 |  |  | $ | 132 |  |  | $ | 3,719 |
Region: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
North and South America |  | $ | 272 |  |  | $ | — |  |  | $ | 272 |  |  | $ | 2,720 |  |  | $ | — |  |  | $ | 2,720 |
Europe |  |  | 1,022 |  |  |  | 135 |  |  |  | 1,157 |  |  |  | 865 |  |  |  | 132 |  |  |  | 997 |
Asia and Australia |  |  | 177 |  |  |  | — |  |  |  | 177 |  |  |  | 2 |  |  |  | — |  |  |  | 2 |
Total |  | $ | 1,471 |  |  | $ | 135 |  |  | $ | 1,606 |  |  | $ | 3,587 |  |  | $ | 132 |  |  | $ | 3,719 |
Revenue |  | $ | 1,471 |  |  | $ | 135 |  |  | $ | 1,606 |  |  | $ | 3,587 |  |  | $ | 132 |  |  | $ | 3,719 |

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