Bitcoin Cash (BCH) sustainability report

Bitcoin Cash is present on the following networks: Bitcoin Cash.

Bitcoin Cash secures its ledger with proof of work over the SHA-256 hash function, the same arrangement it inherited when it separated from Bitcoin in 2017, and it has since diverged in several respects that matter to how the chain behaves. Block producers assemble pending transactions into a candidate block and search for a header value that hashes below the current threshold; the first to succeed publishes the block, and participants running full validation software accept it only if every rule holds. The branch carrying the greatest accumulated work is the one the network follows, so confirmation deepens as blocks are added rather than arriving as a single moment of finality.

The difficulty threshold is not recalculated on a fortnightly boundary. Since November 2020 the network has used an exponentially scheduled adjustment that retargets at every block against an absolute schedule, which lets the chain absorb abrupt arrivals and departures of hashing capacity without the stalls and oscillations that a slower, window-based rule produced. This matters here more than it does on other chains, because the hardware is fungible with that of every other SHA-256 network, and capacity moves between them as relative returns shift. A consequence worth stating plainly is that this network commands a modest fraction of the hashing capacity available for its algorithm.

Capacity limits are also handled by an algorithm rather than by periodic negotiation. Since May 2024 the maximum block size has been set by a rule that tracks an exponentially weighted average of how full recent blocks have been, raising the ceiling as sustained demand grows and letting it fall back when demand recedes, with a floor that keeps substantial headroom available at all times.

The validation rules are revised on an annual cadence, with changes prepared through a public proposal process and activated together each 15 May. The upgrade that took effect on 15 May 2026 extended the contract language considerably, adding bounded loops, definable and reusable functions, restored bitwise operators, and standard handling of outputs that pay directly to a script.

Bitcoin Cash is present on the following networks: Bitcoin Cash.

Producing a block earns two kinds of income. New units enter circulation only through the first transaction of each block, in an amount that halves every 210,000 blocks; the reduction of April 2024 brought it to 3.125 units per block, and the schedule ends after a fixed number of further reductions, leaving fees as the sole payment thereafter. Those newly created units are locked for a hundred blocks before they can be spent. Added to that issuance are the fees attached to the transactions the block contains, which pass in full to the producer with no portion destroyed and no protocol-mandated minimum price.

Fees are charged against the space a transaction occupies rather than against the value it moves, and node operators enforce a relay floor expressed per byte. Because the capacity ceiling adapts upward as usage grows, blocks on this network are rarely full in practice, and the competitive bidding seen on congested chains is largely absent; senders ordinarily pay close to the relay floor, and paying more buys little advantage. The corollary is that fee income is small relative to issuance, so the economics of block production are dominated by the subsidy and by how returns here compare with other chains sharing the algorithm.

Contract execution is priced quite differently from metered virtual-machine designs. There is no per-operation charge and no fee denominated in units of computation; script execution is instead constrained by limits that scale with the size of the transaction being validated, so a contract buys its computational budget by occupying space, and complexity is paid for through the ordinary size-based fee. Nothing is charged for holding state over time, and unspent outputs incur no recurring cost.

There is no staking, no delegation, and no penalty apparatus. Participants are not registered, hold no bond, and cannot be suspended or have a deposit confiscated, because nothing of theirs is held by the protocol. The discipline is that computation spent on an invalid or losing block is simply lost. Participants who validate without producing blocks are not paid at all.

Bitcoin Cash is present on the following networks: Bitcoin Cash.

Because blocks here are produced by proof of work, the consumption estimate is built from the economics of mining rather than from a survey of nodes. The algorithm the protocol uses determines which hardware is relevant, confining it to purpose-built SHA-256 devices, and those are enumerated with their published throughput and power ratings. What such a device can earn is calculated from the issuance and fees the chain itself paid out over the period, divided across the network's observed hashing rate. Comparing that revenue with an assumed running cost — principally electricity, plus the overhead of housing and cooling the machine — gives a break-even efficiency, and devices that would lose money at that point are treated as idle and excluded.

The devices that remain are apportioned so their combined throughput matches what the network actually produced, and their power draw is aggregated and extended over the reporting period, with an overhead allowance for the facilities around them. Two adjustments are specific to this network. Because the hardware is identical to that used on other chains with the same algorithm, and operators move capacity between them, the fleet assumption is drawn from the SHA-256 mining population as a whole and this chain is assigned its share by observed hashing rate. And where a single device submits work to several chains simultaneously, that overlap is recognized so the same electricity is not charged more than once. Consumption attributable to the associated sidechain is added where it falls within scope, and a network total is apportioned to an individual asset carried on the chain in proportion to observed on-chain transfer activity.

No part of this is measured directly. There is no instrumentation, no reporting from operators, and no verified inventory of machines; the figure is inferred from chain data and manufacturer specifications. Its sensitivity concentrates in the deployed efficiency mix, the electricity price chosen for the break-even test, and the overhead factor. Where the evidence does not settle a choice, the more conservative option is taken, meaning the one more likely to overstate impact. Figures are restated as observation improves.

Bitcoin Cash is present on the following networks: Bitcoin Cash.

What share of the network's electricity comes from renewable generation depends on where the machines sit, so establishing that geography is the substance of the method. Observable signals are collected first: the addresses and regions advertised by reachable peers, whatever block-producing pools disclose about their own operating locations, and measurements gathered by open crawlers alongside purpose-built ones. The coverage this yields is incomplete, because the equipment performing the hashing is generally not the equipment that announces itself publicly, and pools have commercial reasons to say little about siting.

The gap is wider here than on larger chains, since this network's share of the hashing capacity built for its algorithm is small and much of that capacity is supplied by operators who also serve other chains and do not report per-chain locations. Where the network's own distribution cannot be observed with confidence, the geographic profile of the wider population of operators running the same algorithm under a comparable reward structure is used in its place, on the reasoning that identical hardware and identical economics lead operators to the same kinds of places.

The resulting distribution, expressed as shares of estimated consumption by country or region, is then combined with published statistics on each region's generation mix to give a consumption-weighted renewable share. Those statistics are taken from Share of electricity generated by renewables, compiled and processed by Our World in Data from Ember and the Energy Institute's Statistical Review of World Energy. Energy intensity is reported as a marginal figure: the additional energy attributable to one more transaction over the period.

Two caveats belong with the result. Regional averages cannot represent a facility supplied under a direct contract with a particular generator, drawing on its own on-site generation, or consuming power that would otherwise have gone to waste. And since blocks are produced on a schedule set by the difficulty rule rather than by demand, and blocks here are commonly far from full, the per-transaction figure allocates a largely fixed total across whatever traffic occurred and will move sharply with usage alone.

Bitcoin Cash is present on the following networks: Bitcoin Cash.

The emissions estimate reuses the geographic breakdown prepared for the energy assessment. Estimated consumption, once distributed across countries and regions, is multiplied region by region by a factor for the greenhouse gas content of electricity delivered there, and the results are added together. Those factors are taken from Carbon intensity of electricity generation, compiled and processed by Our World in Data from Ember and the Energy Institute's Statistical Review of World Energy and published under the CC BY 4.0 license.

The distinction between the two reported scopes is one of ownership rather than magnitude. Scope 1 counts emissions released by equipment the infrastructure operators own or control themselves — fuel combusted on their own premises. Operating hashing hardware and validating nodes involves no such combustion under ordinary circumstances, and the protocol requires none, so nothing is attributed to scope 1 and it is reported as zero. Scope 2 counts the emissions released at the generating stations that supply the electricity those machines draw. That term carries essentially the whole footprint of the network, and because it is the product of the consumption estimate and the location estimate, it inherits the uncertainty of both: an error in the assumed hardware mix and an error in the assumed geography compound rather than cancel.

Greenhouse gas intensity is stated on the same marginal basis used for energy intensity, as the emissions attributable to one additional transaction over the reporting period.

The boundaries of the calculation should be read carefully. It is location-based, charging each unit of electricity at the average intensity of the grid it came from, and therefore takes no account of supply contracts or certificates that a market-based method would credit against the total. Emissions embodied in manufacturing and transporting the hardware, and in disposing of it at end of life, lie outside operational scope 1 and scope 2 reporting and are excluded. The published intensities are annual regional averages that lag the period they cover, and the generation that responds at the margin to additional demand need not resemble the regional average at all.