Public miner audit · Oct 12, 2026 · 5 min read
CleanSpark in the first half of 2026: 5.3¢ per kWh all-in, and $45,000 per bitcoin
CleanSpark reports the kilowatt-hours its sites used, so its power rate needs no estimate. From January to June 2026 it mined 3,715 bitcoin at 5.3¢ per kWh all-in, $45,000 per bitcoin. Its site staff, property tax and insurance sit in overhead, which brings the loaded rate to 7.7¢.
TL;DR
- It mined 3,715 bitcoin from January to June 2026, net of pool fees, all of it self-mined through one pool.
- Its power cost 5.3¢ per kWh, from 3.16 million MWh that the company reports itself. No estimate is needed.
- All-in is almost the same as power, at 5.3¢, because its cost of revenue holds only power and utilities. Site staff, property tax and insurance sit in overhead.
- With overhead added, 7.7¢ per kWh and $65,800 per bitcoin, against $73,900 of revenue per bitcoin mined.
- Each bitcoin cost $45,000 to make all-in, against $52,600 in the Oct–Dec 2025 quarter.
What CleanSpark reported
CleanSpark is a US filer whose fiscal year ends on 30 September, so the calendar first half of 2026 is its fiscal Q2 (January to March) and Q3 (April to June). Each quarter it files a 10-Q and an earnings release: Jan–Mar 10-Q, Apr–Jun 10-Q, and the Oct–Dec 2025 10-Q, which we use as a context quarter.
All of its revenue is bitcoin mining, earned through a single pool, Foundry, and it reports one segment. Its average hashrate in the last month of each quarter was 47.1 EH/s in December 2025, 47.3 EH/s in March 2026 and 42.6 EH/s in June 2026. Fleet efficiency at period end improved from 16.8 to 16.2 to 15.8 J/TH. About 225,000 miners were in service at 30 June 2026, out of about 326,500 owned.
It now describes itself as a data centre developer. On 10 July 2026 it signed a 20-year, 175 MW AI data centre lease at Sandersville, Georgia, after which mining at that site will stop. No AI revenue had been booked by 30 June.
The power bill
CleanSpark discloses, for its owned facilities, both its total energy expense and the kilowatt-hours its sites used. All its mining runs at owned facilities, so dividing one by the other gives the power rate directly.
From January to March it spent $81.6 million on power for 1,555,407 MWh: 5.2¢ per kWh. From April to June it spent $85.3 million for 1,602,779 MWh: 5.3¢. Over the half, $167.0 million for 3,158,186 MWh, 5.3¢. In Oct–Dec 2025 the rate was 5.6¢.
The company states its own rate, and ours agrees. Its 10-Qs give "average power prices" of $0.052 and $0.053 per kWh for the two quarters, and $0.056 for Oct–Dec 2025. It also gives a "cost of energy per bitcoin mined" of $45,387 and $44,317. Ours is $45,500 and $44,400. The small gap is the divisor: the company divides by bitcoin mined before the pool fee of about 0.2%, and we divide by bitcoin received.
It discloses no curtailment or demand-response credits. Its power contracts in Georgia, Mississippi, Tennessee and Wyoming are variable-priced, and it switches miners off when power costs more than the bitcoin they would earn.
Everything else it takes to run the sites
CleanSpark's cost of revenue holds power and a small line of non-energy utilities: $44,000 and $170,000 in the two quarters. That is why its all-in rate, 5.3¢, is almost the same as its power rate.
The rest of what it takes to run a site sits lower in the income statement. Its 10-Qs say payroll rose with "increased headcount due to expansion of operational locations", and that general and administrative costs include property taxes, rent and maintenance. These cannot be separated from head-office costs, so for CleanSpark the loaded rate is closer to what other miners report as all-in.
Overhead (professional fees, payroll and G&A, less stock-based pay) was $38.6 million and $38.7 million in the two quarters, $77.3 million over the half. Mining is all of its revenue, so all of it is allocated to mining. That gives a loaded rate of 7.7¢ per kWh. Stock-based pay of $26.6 million over the half is shown separately. Part of the overhead now funds the data centre plans, so the loaded rate is, if anything, high for mining alone.
What a bitcoin cost them
At the power layer each bitcoin cost $44,900 over the half. All-in it cost $45,000. Loaded with overhead, $65,800, and $73,000 with stock-based pay. Revenue per bitcoin mined was $73,900, so the loaded cost left about $8,100 per bitcoin before hardware.
The cost per bitcoin fell from $52,600 in Oct–Dec 2025 to $44,500 in Apr–Jun 2026, as the power rate eased from 5.6¢ to 5.3¢ and the fleet became more efficient. Bitcoin mined held between 1,795 and 1,920 a quarter.
| Period | Bitcoin mined | Power ¢/kWh | All-in ¢/kWh | Loaded ¢/kWh | Power $/BTC | All-in $/BTC | Loaded $/BTC | Revenue $/BTC |
|---|---|---|---|---|---|---|---|---|
| Oct–Dec 2025 (fiscal Q1, context) | 1,817 | 5.6¢ | 5.6¢ | 7.4¢ | $52,600 | $52,600 | $70,500 | $99,700 |
| Jan–Mar 2026 (fiscal Q2) | 1,795 | 5.2¢ | 5.3¢ | 7.7¢ | $45,500 | $45,500 | $67,000 | $76,000 |
| Apr–Jun 2026 (fiscal Q3) | 1,920 | 5.3¢ | 5.3¢ | 7.7¢ | $44,400 | $44,500 | $64,700 | $71,900 |
| H1 2026 | 3,715 | 5.3¢ | 5.3¢ | 7.7¢ | $44,900 | $45,000 | $65,800 | $73,900 |
The hardware
Depreciation and amortisation was $226.9 million over the half, $204.2 million of it on miners. The company puts miner depreciation at $58,029 per bitcoin in Jan–Mar and $51,871 in Apr–Jun. Impairments were $4.0 million, a transformer deposit written off in March, with none on miners in the half. Payments for miners came to $13.9 million over the half.
We keep these out of cost per bitcoin. A machine is the roof over the operation, replaced from what the operation earns. It is not part of what each bitcoin costs to make. They are shown in full here so nothing is hidden.
| Period | Depreciation and amortisation | Of which miners | Impairments | Payments for miners |
|---|---|---|---|---|
| Oct–Dec 2025 (fiscal Q1, context) | $106.3M | $95.1M | $1.4M | $18.5M |
| Jan–Mar 2026 (fiscal Q2) | $115.9M | $104.4M | $4.0M | −$3.7M |
| Apr–Jun 2026 (fiscal Q3) | $111.0M | $99.9M | $0 | $17.6M |
| H1 2026 | $226.9M | $204.2M | $4.0M | $13.9M |
What it means
Hosting at Firsthand's sites runs from 3.9¢ to 6.5¢ per kWh all-in, on our sites page. CleanSpark's all-in rate in the first half of 2026 was 5.3¢, or 7.7¢ with the overhead that, in its accounts, includes site staff, property tax and insurance. At those rates it mined 3,715 bitcoin in six months.
Mining output depends on bitcoin's price, difficulty and uptime, and isn't guaranteed.
This is our analysis of the company's public filings, not an audit in the accounting sense.
Method and sources
Bitcoin mined is the figure net of pool fees in each 10-Q: 1,817, 1,795 and 1,920. The 10-Qs also give a slightly higher count before the pool fee, which the company uses for its own per-bitcoin metrics. The Oct–Dec 2025 10-Q describes 1,817 as "gross of Foundry fees", but the three quarters add up to the nine-month figure of 5,532 that its Apr–Jun 10-Q calls net, so we treat it as net.
Power cost and energy used come from the MD&A table "Analysis of costs to mine one bitcoin": total energy expense and total kWh utilized at owned facilities. MWh is reported, not estimated. Other direct cost is the "non-energy utilities" line in the same table. Cost of revenue equals energy plus that line.
Overhead is professional fees, payroll and G&A from the income statement, less stock-based pay from the Adjusted EBITDA reconciliation in each earnings release. Mining is 100% of revenue, so the mining share is one. Hashrate is the company's figure for the last month of each quarter, not a quarterly average.
Payments for miners are the cash-flow line "Payments on miners and mining equipment, including deposits". The 10-Qs give it year to date, so each quarter is the difference between two filings. The six-month figure is lower than the three-month one, which gives a negative Jan–Mar value. Purchases of other fixed assets, $43.7 million over the half, include data centre construction and are left out.
Every figure here comes from the filings listed below.
Sources and further reading
- Form 10-Q for the quarter ended 30 June 2026 — CleanSpark, 6 Aug 2026
- CleanSpark reports third fiscal quarter 2026 results (8-K, Exhibit 99.1) — CleanSpark, 6 Aug 2026
- Form 10-Q for the quarter ended 31 March 2026 — CleanSpark, 11 May 2026
- CleanSpark reports second fiscal quarter 2026 results (8-K, Exhibit 99.1) — CleanSpark, 11 May 2026
- Form 10-Q for the quarter ended 31 December 2025 — CleanSpark, 5 Feb 2026
- CleanSpark reports first fiscal quarter 2026 results (8-K, Exhibit 99.1) — CleanSpark, 5 Feb 2026
Disclosure
Firsthand Bitcoin sells and hosts mining hardware. This is our analysis of the company's public filings, not an audit in the accounting sense, and it is not investment advice. Every reported figure links to the filing it comes from; figures we estimated are labelled, with their inputs. No company paid for or reviewed this page. Corrections are published with the date they were made.