Linea (LINEA) sustainability report

Linea is present on the following networks: Ethereum, Linea.

Ethereum reaches agreement through proof of stake, adopted in September 2022 when the original mining-based chain was retired in favor of a validator-driven consensus layer. The protocol family is usually referred to as Gasper. A fork-choice rule named LMD-GHOST selects the head of the chain by following the branch carrying the greatest accumulated weight of validator votes, while a separate finality gadget, Casper FFG, periodically justifies and then finalizes checkpoints, so that reversing them would require destroying an enormous quantity of bonded value.

Time is divided into slots of twelve seconds, and thirty-two slots form an epoch. For each slot the protocol pseudo-randomly designates one active validator to assemble and publish a block, and assigns the rest to committees that vote on what they believe is the correct head and the correct checkpoints. Under healthy conditions a checkpoint becomes final two epochs after it is proposed, a little under thirteen minutes, after which everything beneath it is treated as settled.

Joining the validator set requires a deposit of no fewer than 32 units of the native asset. Since the protocol upgrade of May 2025 a single validator may hold a far larger balance, up to 2,048 units, and earn on the whole of it, which lets an operator running many minimum-sized validators consolidate them into fewer; the activation floor itself did not change. Entry and exit are rate-limited by a queue measured in staked weight rather than in validator headcount, which bounds how fast the composition of the set can turn over.

Security rests on voting power being bonded. A validator that signs contradictory messages can be proved to have done so and is penalized, and the size of that penalty scales with how much other stake was penalized at the same time, so a coordinated attack is punished far more severely than an isolated fault. Should the chain stop finalizing altogether, a separate mechanism gradually erodes the balances of validators that are not participating until the remainder again represents a large enough majority to finalize. Upgrades during 2024 and 2025 changed how large data payloads are distributed and sampled between nodes, without altering this underlying agreement process.

Linea is a Layer 2 network that executes transactions away from the Ethereum chain and then proves their correctness to it. It has no consensus protocol of its own in the sense a base layer does, and no independent validator set standing behind user funds. What settles the question of what is true on Linea is a cryptographic proof, checked by a contract on Ethereum, showing that the state transition the network claims is precisely what its rules produce from the data it has published.

Three components do the work. A sequencer receives transactions, orders them and produces Layer 2 blocks, which gives users an immediate result. A coordinator drives the pipeline that turns those blocks into batches, requests proofs for them and submits the outcome to Ethereum. A prover generates the succinct zero-knowledge proofs themselves, and that is by a wide margin the most computationally demanding part of the system. During 2026 block production inside the sequencer was moved onto a Byzantine-fault-tolerant protocol of the kind used in permissioned enterprise networks, replacing an earlier proof-of-authority arrangement. The change is groundwork for spreading sequencing across several independent operators, but for now a single operator, the network's originator, produces every block.

Because the proof establishes validity mathematically, there is no dispute window and no requirement that a challenger be watching. Once the contract on Ethereum accepts a proof, the state it attests to is settled, subject only to Ethereum finalizing the block that contains the verification. That is the substantive difference from optimistic designs, where commitments are presumed correct and may be contested for a period afterwards. The network also publishes the full transaction data for each batch to Ethereum rather than only the differences in state, so anyone can rebuild the Layer 2 chain from settlement-layer data alone.

Execution aims to be indistinguishable from Ethereum's, and the remaining differences in gas accounting and state representation have been narrowed successively. Operationally the network remains centralized: sequencer and prover are each run by one party, contract upgrades are not yet constrained by a long user exit window, and independent assessments place it at the earliest tier of the common rollup maturity scale, with staking-based permissionless sequencing described as a later goal.

Linea is present on the following networks: Ethereum, Linea.

Payment inside the protocol flows to validators, the only participants the consensus layer compensates directly. A validator earns newly issued units of the network's native asset for voting promptly and correctly on the head of the chain and on the checkpoints being justified, for serving its turn in the committee that signs headers for light clients, and, when selected to propose, for the block itself. The proposer additionally keeps the priority portion of the fees in that block, together with whatever it receives from the separate market through which many proposers outsource block assembly. There is no delegation inside the consensus rules: stake is either operated directly or entrusted to an operator through arrangements that sit outside the protocol.

Users pay for execution in gas, metered per operation, with writes to persistent state priced far above arithmetic. Every transaction carries a base fee per unit of gas that the protocol sets algorithmically from how full recent blocks have been, and that amount is destroyed rather than paid to anyone, so sustained demand withdraws native asset from circulation. On top of it a user adds a voluntary tip, which goes to the proposer and governs how quickly the transaction is picked up. Data posted on behalf of Layer 2 networks is priced in a second, independent market whose fee is likewise destroyed; a December 2025 upgrade tied the floor of that market to ordinary execution costs so it cannot collapse to a negligible level, and capped the gas any one transaction may consume.

Penalties mirror the rewards. Failing to vote, or voting late or incorrectly, costs a validator roughly what correct behavior would have earned it. Provable equivocation is treated far more harshly: the offender is scheduled for ejection, forfeits part of its balance immediately, and later incurs an additional correlated penalty computed from how much other stake was penalized nearby in time. Prolonged absence while the chain is failing to finalize drains balances until finality can resume. Stakers may take out accumulated rewards without leaving the set, and since 2025 may also trigger a full exit from the execution layer rather than only from the consensus client.

Fees on Linea are paid in ether, the asset used on the settlement layer; no separate asset needs to be held in order to transact. The network runs no staking system, issues no rewards to a validator set and has no delegation inside its protocol, because it has no permissionless set of block producers to pay.

A user's fee has two parts in substance even where it is quoted as a single number. The first covers executing the transaction on the Layer 2, metered in gas on the same schedule Ethereum uses and priced by an algorithmic base fee plus a tip. The second covers what the network must spend on Ethereum, which for a validity rollup is of two kinds: publishing the batch's compressed transaction data, and paying for the on-chain verification of the proof that covers it. Verification is a fixed cost per submission and is spread across every transaction in the batch, so the fuller the batch the less each transaction bears. Data publication has used Ethereum's dedicated data market since 2024, priced separately from ordinary execution and destroyed rather than paid out, and compression improvements on the Layer 2 side reduce how much of that space a batch needs.

Fee revenue first pays the cost of running the sequencer, coordinator and prover and of settling to Ethereum. What remains after those costs is destroyed rather than kept: approximately one fifth as ether, which removes supply on the settlement layer, and the remainder used to acquire and destroy the network's own asset on Ethereum. This arrangement has been in force since late 2025 and ties the economics of both assets to how heavily the network is actually used rather than to a fixed schedule.

Penalties in the usual sense do not exist here, because no participant posts a bond that misbehavior could forfeit. Correctness is not encouraged economically but enforced cryptographically: an operator cannot finalize an invalid state, because no proof of one can be produced. What that leaves exposed is liveness and transaction ordering rather than validity, and it is those risks that the move toward multiple independent sequencers and provers is meant to address.

Linea is present on the following networks: Ethereum, Linea.

The figure reported for this network is assembled machine by machine, treating the computers that run the protocol as the thing that draws electricity. The starting point is an estimate of how many independent nodes are operating, built from crawlers that walk the peer-to-peer layer and record every peer they can reach, supplemented by public listings of infrastructure and staking providers and by the protocol's own visible record of how much stake is active and how it is spread across operators.

A representative hardware profile is then inferred for those machines. The client software publishes what it requires in processor, memory and disk terms, and operators have little reason to provision far beyond that, so the profile is derived from those stated requirements rather than from a survey of individual operators. Power draw for the resulting device classes comes from measurement on representative equipment under controlled laboratory conditions, capturing both the load validating places on a machine and the draw of a machine that is powered on but momentarily idle, which for a network of this kind accounts for a large share of the total. Multiplying measured per-device draw across the estimated population over the reporting period yields the network figure. Where a disclosure concerns one of the many assets issued on this network rather than the network itself, a portion of the network total is assigned to it in proportion to observed on-chain transfer volumes.

The limits deserve stating plainly. The node count records what is reachable, not a census, and machines behind restrictive network configurations are missed. The hardware profile is a reasoned inference from published software requirements, not a record of what any particular operator bought. Nothing here is metered at the wall. Where the evidence runs out, the assumptions chosen are those that push the estimate upward rather than downward, so the result is more likely to overstate consumption than to understate it, and it is revised as observation improves. The network's own account of its energy profile is published at Ethereum energy consumption.

The estimate for this network is assembled from two components: the machines the network runs itself, and the share of the settlement layer's consumption that its activity causes.

The first component is unusual among Layer 2 designs because proving dominates it. The sequencer, the coordinator and the replica and archive nodes that third parties operate are conventional server workloads, sized from the published requirements of the node software and assigned power figures measured on representative equipment under controlled laboratory conditions, with idle draw counted alongside load. The prover is a different matter. Producing a succinct proof that a whole batch of transactions executed correctly is an intensive computation, run on large multi-core machines and accelerators, and it is performed for every batch the network settles rather than only when something is contested. That makes proving a recurring, throughput-linked energy cost with no counterpart in an optimistic design, and it is modeled as a distinct workload whose draw scales with the volume of transactions proved rather than with elapsed time alone. Efficiency gains in the proving software reduce this component directly, which is one reason the figure moves between reporting periods.

The second component is the settlement layer, which is Ethereum. Its consumption is estimated from its validator population using the node-level method described for that network, and a share is attributed here in proportion to what this network occupies there: the data space its batches consume and the gas its verification and settlement contracts use.

All of this rests on estimation rather than metering. The number and specification of proving machines are inferred from the operator's published architecture and from what the proving workload demands, not read from a meter, and the replica node population is observed through crawlers and public listings and is necessarily incomplete. Where the evidence does not settle a question, the assumption chosen is the one that raises the estimate rather than lowers it, so the result is more likely to overstate than understate, and it is corrected as observation improves. The settlement layer's own account of its energy profile is published at Ethereum energy consumption.

Linea is present on the following networks: Ethereum, Linea.

The renewable share reported here is a weighted average of grid mixes rather than a record of what any operator actually buys. It is produced in two steps: establish where the infrastructure sits, then attach regional electricity statistics to those places.

Location is inferred from what the network exposes publicly. Nodes advertise network addresses in order to be reachable by peers, and those addresses resolve to a country accurately enough to describe an aggregate distribution, even though any single resolution may be wrong. Crawlers of the peer-to-peer layer and public directories of hosting and staking infrastructure supply the input. Where the observable sample is too thin or too skewed to stand for the whole population, the geographic spread of a structurally similar network is substituted, chosen because its participants face comparable hardware costs and comparable pressures over where to site machines, on the reasoning that operators respond to the same commercial forces even where the software differs.

Each location is then matched to published statistics on how electricity in that country or region is generated. The renewable proportion for the network is the consumption-weighted share falling in regions where generation is renewable. Grid averages are used because the alternative, knowing each operator's actual supply contract, is not observable; an operator on a dedicated renewable supply and one drawing ordinary grid power in the same country are treated alike.

Energy intensity is reported on a different basis from total consumption. It is a marginal quantity: the additional electricity attributable to processing one further transaction on the network as it currently runs. For a network whose consumption is driven by a validator set that operates continuously regardless of how busy the chain is, that marginal figure is small, and it is not the total divided by the transaction count. The generation statistics are drawn from Share of electricity generated by renewables, compiled by Our World in Data from Ember's electricity datasets and the Energy Institute's Statistical Review of World Energy.

Most of the electricity behind this network is drawn by proof generation, and proof generation does not happen everywhere. It runs on clusters of high-core-count machines and accelerators in a handful of sites, which gives the geographic weighting an unusual shape: a small number of grids carry most of the weight, and the renewable figure shifts noticeably if the proving fleet is enlarged, retired or moved to a different hosting region. A network of many small scattered nodes averages such changes away. This one does not.

Establishing locations therefore starts with those sites. Hosting regions chosen for the proving fleet, and for the sequencing and coordination services running alongside it, are visible in the operator's published technical material and in the routing of the endpoints it exposes. Independent replica and archive operators form a second, dimmer tier, counted through peer crawling and through directories of infrastructure providers, with a country attached to each by looking up which allocation an announced address falls under. That lookup misfires often enough on any single machine that only the aggregate shape is trusted. A third tier lies outside the network altogether, since part of what is reported here is a slice of the settlement layer, whose validators occupy a far wider spread of grids; that spread is characterized separately and blended in at the weight the slice carries. When a tier resists observation, a stand-in profile is borrowed from a network whose operators choose hosting on comparable commercial grounds.

Generation statistics do the rest. Every country in the weighted distribution carries a published figure for the fraction of its electricity produced from renewable sources, and the network's renewable share is that fraction averaged over the consumption weights. It is a statement about grids rather than about procurement: a proving site buying wind power directly and a neighboring rack on default tariff are indistinguishable under this treatment, and an annual national series cannot describe the hour at which a load actually fell.

Energy intensity means the additional electricity one further transaction brings, with the deployed hardware held as it is. Here that quantity is not close to nothing, because every extra transaction enlarges the work a prover must perform. Generation figures come from Share of electricity generated by renewables, a series Our World in Data maintains from Ember's electricity data and from the Energy Institute's Statistical Review of World Energy.

Linea is present on the following networks: Ethereum, Linea.

Emissions are derived from the consumption estimate rather than measured, by attaching a carbon intensity to each unit of electricity the network is estimated to draw and summing across the network.

The geographic step repeats the one used for the renewable share. Node locations are inferred from publicly observable network data, principally the addresses peers advertise so that others can connect to them, gathered by crawlers and supplemented by public information about where staking and hosting infrastructure is operated. Where that observation is too sparse to characterize the whole population, the distribution of a comparable network stands in for it, selected because its participants face similar operating economics rather than because its software resembles this one. Each region is assigned a carbon intensity, meaning the average greenhouse gas released per unit of electricity generated on that grid, expressed in carbon dioxide equivalent so that methane and the other gases are counted on a common basis. Estimated consumption in a region multiplied by that region's intensity, summed across regions, gives the network total.

The reporting separates two scopes. Scope 1 covers emissions from sources the operators of the infrastructure control directly, such as fuel burned on site in a generator. For a network of this kind, whose participants overwhelmingly run ordinary servers connected to a public grid, there is generally nothing in that category, and it is reported as such rather than left out. Scope 2 covers the indirect emissions embodied in the electricity purchased to run that infrastructure, and that is where essentially the whole footprint sits. Emissions further up the supply chain, such as those from manufacturing and shipping the hardware, fall outside this boundary.

Greenhouse gas intensity follows the same marginal logic as energy intensity: it expresses the additional emissions attributable to one further transaction rather than an average spread across all of them. Because it inherits both the consumption estimate and the grid averages, its uncertainty combines theirs. Carbon intensities are taken from Carbon intensity of electricity generation, compiled by Our World in Data from Ember's electricity datasets and the Energy Institute's Statistical Review of World Energy, and made available under the CC BY 4.0 license.

Where the boundary falls is not obvious here. Two pools of electricity are in scope: the machines the network runs for itself, chiefly the proving cluster together with sequencing, coordination and the replica and archive servers third parties keep; and a slice of the settlement layer, sized by how much of Ethereum's capacity the posted batches and proof verifications occupy. Fabricating the accelerators and constructing the halls that house them lie outside.

Within the boundary nothing is metered for carbon. A coefficient is applied instead: for each country in which consumption has been placed, published statistics give the average greenhouse gas released per unit of electricity generated there, expressed in carbon dioxide equivalent. Estimated electricity is multiplied through and the products added. What makes the calculation distinctive is how lopsided the weights are. Proving concentrates the bulk of the draw into a few hosting sites, so the coefficient of one or two grids governs the answer, and a decision to prove somewhere else would move reported emissions further than most protocol changes could. Those sites are placed from the operator's public technical material; replica nodes by resolving announced addresses to countries, with a borrowed profile from a commercially comparable network covering whatever will not resolve. Settlement-layer validators are placed on their own terms and folded in at the weight their slice carries.

Scope 1 would capture combustion under the operators' own control, an on-site generator being the plain case. In leased facilities full of general-purpose servers there is normally none, and the zero that appears is a finding rather than a gap. Scope 2 is the indirect burden riding on purchased electricity, and effectively the whole figure sits there. National average coefficients mean a site on a specific low-carbon contract scores no differently from a neighbor on default supply.

Greenhouse gas intensity per transaction is marginal rather than averaged: what one additional transaction adds, with the installed fleet unchanged. On this network that increment is real rather than nominal, since one more transaction is one more transaction to prove. It inherits the uncertainty of both the consumption estimate and the grid coefficients. Those coefficients are taken from Carbon intensity of electricity generation, a series Our World in Data builds from Ember's electricity data and from the Energy Institute's Statistical Review of World Energy and releases under the CC BY 4.0 license.