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Progress report · Oct 8, 2026 · 3 min read

Nearly two years in the UAE, the Antminer S21 XP Hyd still clears its power after a halving

Bought in November 2024 and racked in the UAE, the 12 J/TH S21 XP Hyd has paid its power bill the whole way. At 6¢ its line sits under the level hashprice would fall to after the 2028 halving, so the forward figures do not lean on a recovery to clear it.

A Bitmain Antminer S21 XP Hyd water-cooled miner on a dark Firsthand card with the words Bitmain Antminer S21 XP Hyd progress report, 12 J/TH, 473 TH/s hydro-cooled

Bitmain Antminer S21 XP Hyd (473 TH/s)

Bought in November 2024 and racked in the UAE from the first day

A 473 TH/s S21 XP Hyd at 12 J/TH, bought at $11,969 and landed at $14,316, racked in the UAE at 6¢ in November 2024. It is a water-cooled machine, so its home is the UAE, where the water plant and the manufacturer's warranty centre are, and it has been there for all 690 days.

It has mined and kept 0.1608 BTC, worth about $13,755 today, for $6,087 of electricity. That is $7,668 of cashflow, or 54% of its landed cost, on a machine a little under half way through a four-year life. Days spent switched off in that time: 0.

Chart: Coins kept since November 2024, the electricity that made them, and where the forward figures put it by the April 2028 halving.

At 6¢ a coin costs it about what it has all along

At 6¢ it makes a bitcoin for about $39,500 of electricity today, against a bitcoin price of $82,320. Over its run it has averaged about $37,900 a coin. The S21e Hyd, at 17 J/TH, needs about $56,000 for the same coin, and the S23 Hyd, at 9.5 J/TH, about $31,300.

The line it has to clear is simple. A machine's line is the hashprice at which it stops covering its power, and at 12 J/TH a petahash uses 288 kWh a day: $17.28 at 6¢ and $11.23 at Nigeria's 3.9¢. Network hashprice was $40.74 per petahash per day on 7 October on our hashprice chart, so the line is well under half of it.

At 12 J/TH a petahash burns 288 kWh a day. That is $17.28 at 6¢.

Chart: What a coin costs it in electricity against bitcoin's price. The gap between the lines is the cashflow.

The halving line sits under the halved hashprice

The 2028 halving cuts the coins a petahash earns in half. At today's price and difficulty that would put hashprice near $20, above this machine's $17.28 line at 6¢. It is today's conditions held flat, not a forecast, and it is why our forward figures assume bitcoin returns to its previous high, as every projection on the site does.

On that assumption, with the price back at $124,493, it adds another 0.125 BTC by April 2028, worth about $15,593: roughly 1.6× its landed cost by the halving, with the machine still earning afterwards. A machine at 18.5 J/TH, which has a line of $26.64, cannot say that at 6¢. This is what efficiency decides about halvings.

Chart: Network hashprice per petahash per day. The S21 XP Hyd needs about $17 of it at 6¢ and about $11 at 3.9¢. Open the chart

The entry price has settled where a buyer can use it

The first price we hold for it, on 11 October 2024, was $23.52 a terahash, after ForkLog reported pre-orders at $21.5 a terahash in June 2024, for delivery from the fourth quarter. It is $13.44 today, $6,357 a unit, for the same 473 TH/s at the same 12 J/TH.

A low entry price does a lot of work, and at today's price this machine returns about 40% in its first year. D-Central's review of the machine gives the loop it needs as 8 to 10 litres of coolant a minute at up to 3.5 bar, which is a plant job, not a shelf job.

Chart: What it has cost, from the first price we hold. The machine and its output are unchanged; only the entry price has moved.

Who should buy one, and who should look one step on

Buy it if you want a 12 J/TH water-cooled machine nearly two years into its life, you are racking in the UAE, and you want a position that clears its power after the halving at 6¢ without leaning on a recovery.

Look at the S21e XP Hyd instead if the first-year return is what you are after: at $8.82 a terahash it returns about 50% in year one against this machine's 40%, for a coin that costs about $42,800. The figure below ranks what beats this machine on cost per coin and then on first-year return, in stock today.

What beats it on cost per coin and on first-year return, in stock today.

Sources and further reading

Which machines this covers

Disclosure

Firsthand Bitcoin sells and hosts mining hardware, including this machine. No manufacturer, distributor or affiliate programme paid for or reviewed this page and we take no commission on the links above. Historical figures are computed from daily bitcoin price and network hashprice, each day valued at its own prices. Nothing here is investment advice.