The IceRiver KS3 needs electricity at 1.50 pence per kilowatt hour to break even. The cheapest half-hour published on Octopus Agile in Eastern England today was 30.27 pence. That is not a narrow miss or a question of finding the right tariff: it is a factor of twenty, at the cheapest single slot of the day.
The machine
Eight terahashes per second on kHeavyHash, 3,200 watts, both quoted by IceRiver at plus or minus ten per cent, giving 400 joules per terahash. It is 370 by 195 by 290 millimetres, 14.7 kilograms, takes 170 to 300 volts, and the power cable is not included. Warranty is 180 days from shipment. IceRiver’s own page lists it as sold out.
Mind the model. The KS3M is not a middle option — it is worse on both axes, 6 TH/s for 3,400 watts, or 567 J/TH. Every figure here is the 8 TH/s KS3 at 3,200 watts, which is also the bin the quoted prices refer to.
Why the numbers look like this
Kaspa’s network runs at 326,694 TH/s, so a KS3 is one part in 40,837 of it. At ten blocks a second and 2.18267645 KAS a block the network issues 1,885,832 KAS a day, which gives the machine 46.18 KAS, or £1.15 after a one per cent pool fee. It draws 76.8 kilowatt hours to do it. That is where 1.50 pence comes from.
Two things make it worse from here. Kaspa reduces emission by 2 to the power of one twelfth every month, about 5.6 per cent, and the next reduction lands on 5 October — roughly half the revenue gone over a year, regardless of price. And the usual consolation, that difficulty will fall as others switch off, has already happened: network hashrate is down about 80 per cent from its January 2025 peak of 1,592,196 TH/s and the machine is still twenty times underwater.
| Mined per day | 46.18 KAS (£1.15 net of pool fee) |
| Consumes per day | 76.8 kWh |
| Break-even electricity | 1.50 p/kWh |
| Cheapest Agile half-hour today | 30.27 p/kWh |
| Agile median today | 36.20 p/kWh |
| Ofgem cap, to 30 September | 26.11 p/kWh |
| Loss per day at the cap | −£18.90 |
| Revenue per megawatt per day | £360 |
| Cost of a megawatt-day at the cap | £6,266 |
A megawatt of KS3 earns £360 of Kaspa a day and eats £6,266 of electricity to do it.
The case against, in practical terms
Payback is not long, it is undefined: daily cash flow is negative at every UK price, so the machine never repays its purchase and the hole deepens. At the Ofgem cap a unit landed for about £1,730 loses its entire purchase price again in electricity every 92 days. Even at zero pence a unit it needs 1,501 days — against roughly 533 days of Kaspa emission left at the current rate.
Then the ordinary problems. Around 75 decibels, continuously, from a figure IceRiver does not publish. Some 3.2 kilowatts of heat into one room, on a circuit of its own. Warranty is 180 days to the original purchaser and IceRiver states that on resale the responsibility shifts to the reseller — and since essentially all stock is now used, a UK buyer gets nothing from IceRiver. Repair centres are in Hong Kong, the United States, Canada and the UAE, with the customer paying freight out.
The case for
Two conditions, and only two carry weight. Power at or below roughly 1.5 pence, which in practice means curtailed generation or behind-the-meter supply that would otherwise be spilled; no UK domestic tariff comes close. Or you want 3.2 kilowatts of continuous heat in a workshop, would be paying for it electrically anyway, and treat £1.15 a day of Kaspa as a rebate on a heater — about 5.7 per cent of the bill.
Anything else is a leveraged bet on the KAS price that costs £18.90 a day to carry. Buying £1,444 of Kaspa outright gives the same direction with no carry, no noise and no freight to Hong Kong.
Sources, all retrieved 14 September 2026: iceriver.io for KS3 and KS3M specifications, pricing and warranty terms; api.kaspa.org for difficulty, block reward, halving schedule, supply, live hashrate (326,694 TH/s at 08:12 UTC, and drifting through the morning) and the all-time peak; CoinGecko for KAS at £0.02520505 at 08:11:40 UTC; the Octopus Agile Eastern England API; Ofgem for the price cap; GOV.UK for the temporary zero rate of VAT on domestic electricity from 1 October; BT-Miners, asicprices.com, ASICMinerValue and The Mining Shop for prices; d-central and Zeus Mining for firmware and fault documentation. Every profitability figure was derived here in python3 from network data, never from a mining calculator, and the emission reconciles to nine significant figures with Kaspa’s chromatic schedule at month 52. All figures are the 8 TH/s KS3 at 3,200 W; the KS3M at 6 TH/s and 3,400 W is a different machine and its numbers are not interchangeable. Only 44 of 48 half-hourly Agile rates had been published when we fetched, so today is not a full day, and unusually there were no negative or sub-30p slots at all. Contested: a used KS3 is listed at $730 by one vendor and $1,950 by another, while aggregators still carry $12,499 and $14,500 “new” entries we judge stale, since the manufacturer cannot supply the machine; the 75 dB noise figure and the KS3L specification are third-party, not IceRiver’s; UK import duty rate and commodity code could not be verified today. Not a recommendation to buy anything.