Crypto Mining With Solar Panels: The UK Cost & Profit Guide (2026)

Can you make a profit mining crypto with solar panels?

Wondering if you can put some of your spare solar to work by mining Bitcoin or other cryptocurrencies? It’s a fair idea, but the business case is far from perfect. In most cases, simply selling your surplus power to the grid is as profitable or more so. In others, running a miner entirely on spare solar and making use of the heat it produces can tip the balance, but payback is still long, and mining equipment turns obsolete fast.

Let’s explore the arguments in detail

What solar-powered crypto mining means

Crypto mining is the process of running specialised computers that compete to validate blocks of transactions on a blockchain and earn newly issued coins as a reward. For Bitcoin, that work is done by ASIC miners (application-specific integrated circuits) built for a single job and typically drawing 1.5kW to 5.5kW of power, around the clock. Ethereum-style GPU mining largely ended in 2022 when Ethereum switched to proof-of-stake, so in 2026 home mining almost always means Bitcoin or a smaller SHA-256 coin.

Solar-powered mining changes only one thing: the source of the electricity. Instead of drawing every watt from the grid, the miner runs on power from your panels, with any shortfall topped up from the grid or a battery, and any surplus stored or exported. That single swap is where all the appeal and all the traps live, because a miner’s profit is dominated by the price of the power it eats.

The number that decides everything

The only figure that tells you whether solar mining is worth it is Bitcoin revenue per kWh. Work that out, and you can compare it directly against every other thing you could do with the same kWh.

Revenue per kWh depends almost entirely on the miner’s efficiency in joules per terahash. At the September 2026 hashprice of around $39.63 per petahash per day and a Bitcoin price near £64,000, here’s what a kWh of mining earns across three tiers of hardware, against the three things a UK home could otherwise do with that same kWh.

That table overturns the usual pitch. The best miner money can buy earns about the same per kWh as a good export tariff. A typical home miner earns less. And an older second-hand rig, the kind people are tempted by because it’s cheap, earns barely a third of what exporting pays. The reason so many articles claim solar mining is “pure profit” is that they compare mining against the 26p you pay to import, while forgetting that the surplus solar you feed the miner had its own value: the 12p to 15p you gave up by not exporting it.

Can UK solar actually run a miner?

Here’s the second hard truth. A Bitcoin ASIC wants to run 24 hours a day, seven days a week. Solar panels produce for a few hours around midday, mostly in summer, and produce nothing at night. A typical UK 4kW array averages only about 0.4kW across the year once you account for darkness, weather and season. An air-cooled miner alone draws 3.6kW. The arithmetic doesn’t meet in the middle.

To run a single 3.6kW miner around the clock on solar alone, you’d need an array of roughly 35kW plus a very large battery, which is absurd for a house and still wouldn’t cover a dark December week. So home solar mining is never continuous, sun-only mining. In practice it takes one of three realistic forms:

• Surplus-only mining. The miner switches on only when your panels are producing more than the house is using, and switches off otherwise. You monetise midday surplus that would have been exported.
• Battery-buffered mining. A home battery stores midday surplus and feeds the miner for a few extra hours, smoothing the peaks. This adds cost and the round-trip losses eat into returns.
• Solar-assisted mining. The miner runs continuously, on solar when the sun is out and grid when it’s not. Only viable if your grid rate is very low, such as an overnight off-peak window when you time high loads to cheap power.

The first approach is the sensible default for a UK home. It needs a controller that watches your export and starts or stops the miner automatically, which modern mining firmware and a smart relay handle for a small cost. It also means the miner spends most of the year switched off, which limits how much it can ever earn.

The three cases where it makes sense

Solar crypto mining is worth doing in three specific situations, and pointless in the rest.

Case 1: Your surplus solar is being wasted

Some homes can’t export, or export for almost nothing. If your grid connection is capped by an export limitation device, if you never signed up to a SEG tariff, or if you have a large array that regularly generates more than you can use or sell, that surplus is worth 0p. Turning wasted solar into 4p to 13p of Bitcoin can be found money. This is the strongest pure-economics case, and it applies to more homes than you might think, especially larger systems and rural properties with export restrictions.

Case 2: You use the heat

An ASIC miner converts almost all the electricity it draws into heat. That’s normally seen as a nuisance, but flip it around and a miner is a nearly 100% efficient electric heater that happens to earn Bitcoin as a by-product. If it sits in a room you would otherwise heat with an electric heater, the power it uses does the heating job you were going to pay for anyway, and the coin is a bonus on top. A small industry of “hashrate heating” appliances has grown up around exactly this idea. The New York Times’ Wirecutter reviewed the Heatbit Trio, a space heater that doubles as a Bitcoin mining rig.

Case 3: You are off-grid or building for independence

For off-grid setups with no export option at all, a miner is a way to put oversized solar and battery capacity to work on days when the batteries are already full. It’s a genuine use for otherwise-dumped energy, though the upfront cost of the solar and storage needed to feed it is high, and UK winter output is thin. Treat it as a niche for people already committed to a large off-grid build, not a reason to go off-grid.

What it costs to set up in 2026

Assuming you already have solar, the cost of adding mining depends on which route you take. Below is a realistic breakdown for a dedicated air-cooled miner.

If you also want a battery to extend runtime beyond peak sun, add roughly £4,500 to £7,000 for around 10kWh; our full guide to solar battery storage costs breaks the options down. A purpose-built Bitcoin heater is a very different budget: models such as the Heatbit Maxi Pro land at around £1,150 and plug into a normal socket with no enclosure or extra circuit needed, though they hash far more slowly. If you don’t yet have panels, the mining changes nothing about the array itself; our guide to how much a solar system costs covers that separately.

Best hardware for solar mining

There’s no single best miner, only the best fit for how you intend to run it. For a typical UK home, we rate a purpose-built Bitcoin heater as the most sensible entry point. Here are three routes compared.

The Heatbit-style heater wins for the home not because it earns the most Bitcoin per kWh (it doesn’t; its efficiency is modest) but because it’s the only option that lines up with a real house: it draws the same 1.5kW as an ordinary electric heater, it’s quiet enough to sit in a room, and its heat is the whole point. These units connect over Wi-Fi and are managed through an app. The industrial S23 Hydro is the efficiency king but needs three-phase power and a liquid-cooling unit, which rules out almost every home. The air-cooled S21 XP sits in between: powerful and reasonably efficient, but loud and only worth running if you have a large, regular surplus and somewhere to put it.

Our verdict, scored

Here’s how solar crypto mining rates for a UK household in 2026. The headline score is deliberately middling, because the answer depends so heavily on your situation. Read the rows, not just the number.

Tax: what HMRC expects

Any Bitcoin you mine is taxable, and the rules are clear even if the record-keeping is tedious. HMRC expects most individuals mining at home to report it as miscellaneous income, at the sterling value of the coins on the day they’re received. That value is added to your other income and taxed at your marginal rate of 20%, 40% or 45% outside Scotland.

There’s relief for small-scale miners. A £1,000 trading allowance covers the first £1,000 of mining income, so casual mining below that threshold generally needs no reporting. Above it, you declare through Self Assessment. If you later sell the coins, a second tax applies: the sterling value at receipt becomes your acquisition cost for Capital Gains Tax, and any further gain when you sell is taxable, with a £3,000 annual exempt amount for 2026/27. Mining at a large, organised, commercial scale can instead be treated as trading income, which changes the picture and may bring National Insurance into play.

A realistic worked example

Take a common UK home: an existing 5kW array with a 10kWh battery, on a 15p export tariff. The owner adds a quiet 1.5kW Bitcoin heater and runs it on midday surplus in summer and as a room heater in winter.

On summer surplus, the heater might mine for a few hundred hours a year, producing perhaps £20 to £40 of Bitcoin. But that surplus could have exported for about three times as much, so summer mining loses money. The real value comes in winter. Running the same 1.5kW as heat in a room the owner would otherwise warm with electric radiators costs no more than that heating would have cost, and adds maybe £50 to £120 of Bitcoin across the heating season on top. Total upside with the heater off in summer: roughly £50 to £120 a year, against a £1,150 heater. Payback lands somewhere around 10 to 23 years, by which point the mining hardware is likely obsolete.

Now the same numbers with a £3,400 air-cooled ASIC run only on summer surplus. It earns about 9p of Bitcoin for each kWh of surplus it consumes, against the 15p that kWh would have exported for, so it loses to exporting while costing thousands upfront and adding noise. The conclusion is consistent: as a straight investment, solar mining struggles to beat simply selling your surplus. As a way to heat a room or use energy that would otherwise be thrown away, it comes closest to earning its keep.