Edenville Energy's after-tax losses rose to £551,337 in the six months to the end of June - up from £446,801 last time.
Net assets stood at £6,805,216 compared with £6,501,141 a year ago.
The total comprehensive loss for the period was £841,877, which included a loss of £290,540 arising from the translation of the Tanzanian subsidiary company accounts from US dollars to sterling.
Chief executive Rufus Short said: 'The first half of 2017 was an extremely busy and transformational period for the company.
'Having raised funds in February to start production, we have been able to rapidly put in place the required infrastructure and are seeing strong demand for our coal.
'We look forward to the wash plant being operational shortly and commencing sales of washed coal, whilst continuing to advance our coal-to-power project in conjunction with our partner Sinohydro. 'The remainder of 2017 is expected to be equally busy and we look forward to providing updates as matters progress.'