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Energy · Updated July 2026Momentum · accelerating

How close are we to electrochemical ammonia?Can we make fertilizer directly with electricity?

or, simply: Can we make fertilizer directly with electricity?or, precisely: How close are we to electrochemical ammonia?

Verified lithium-mediated cells now combine high selectivity with continuous operation, but no system has simultaneously demonstrated industrial current density, energy efficiency, scale and lifetime.Small cells can now make ammonia from nitrogen reliably for days, but they are still far too slow and energy-hungry to replace an ammonia plant.

We are here

Whole-cell energy use remains extreme - Pulsed laboratory configurations reported 402.96 and 709.52 MWh/t NH3, corresponding to 1.37% and 0.78% production energy efficiency. Next up - Integrated-cell target comes due (expected Apr 2029).

01 · Where we stand

State of playWhere electrochemical ammonia stands right now

The current stage, the honest metric, and the single threshold that gates the next stage. Each threshold is a falsifiable claim with a named next test.How far up the ladder we've climbed, the honest verdict, and the one thing blocking the next step.

The five stagesMaturity ladder
Deployed
Out in the real worldDeployed at scale
Scaling
Making it cheap enough at scaleScaling toward competitive cost
Engineering
Building one that pays for itselfEngineering a system that pays back
Lab demo← HERE
Shown to work in a labDemonstrated in the laboratory
Theoretical
The idea is worked out on paperTheoretical basis established
The honest verdictVerified state

Small cells can now make ammonia from nitrogen reliably for days, but they are still far too slow and energy-hungry to replace an ammonia plant.Verified lithium-mediated cells now combine high selectivity with continuous operation, but no system has simultaneously demonstrated industrial current density, energy efficiency, scale and lifetime.

38.4Best result so farDerived from 60 mA/cm² total current × 64% FE; 300-hour run
400Modeled commercial threshold - not an achieved plant result
Blocking the next stepBlocking threshold

Make ammonia about ten times fasterReach 400 mA/cm² ammonia partial current Next test: An independently measured integrated stack must pair industrial rate with high energy efficiency, selectivity and long life.

The verdict, in five rungsHow far up the ladder↓ next — the thresholds & the gap
01 · The evidence

The thresholds that gate the next stageWhat has to happen next

Each threshold is a falsifiable claim with a named next test; the gap chart shows how far today's metric sits from the goal.Each row is one thing that has to be proven — and how far today's number is from the target.

Verify nitrogen provenanceProve the ammonia came from nitrogen gas✓ Achieved · 2019
100%
Proven byA rigorous Nature protocol quantified contamination and confirmed lithium-mediated nitrogen reduction.
Reach at least 90% Faradaic efficiencySend almost all the charge to ammonia✓ Achieved · 2022
100%
Proven byA 0.15 cm² nickel-wire experiment reported current-to-ammonia efficiency close to 100%.
Sustain 300 hours of continuous flowKeep a flow cell running for nearly two weeks✓ Achieved · Mar 2024
100%
Proven byA 25 cm² cell ran for 300 hours at 1 bar and room temperature with 64 ± 1% Faradaic efficiency.
Reach 400 mA/cm² ammonia partial currentMake ammonia about ten times fasterEarly
10%
Next testAn independently measured integrated stack must pair industrial rate with high energy efficiency, selectivity and long life.
THRESHOLDS - Thresholds for Electrochemical Ammonia.
Scale
Ammonia partial current density over time, with measured values, projected values, and a goal at 400 mA/cm².10100Ammonia partial current density · mA/cm²Year20202021202320242029GOAL 400 · Modeled commercial threshold - no…MACAROON April 2029 project targetGas-diffusion cathode; 35 ±…Derived from 60 mA/cm² tota…MACAROON project target; no…~361.6 mA/cm² to goal
NOTE - Ammonia partial current is the portion of total current that actually produces NH3. The 2021, 2023 and 2024 points are calculated from each paper's total current and Faradaic efficiency. Conditions, areas and durations differ, so this is a performance comparison rather than a record curve. The 300 and 400 mA/cm² lines are project and model targets, not commercial production.
02 · How we got here

The record behind the verdict

Major events set large; context events set small but never hidden. Everything below the TODAY rule is a schedule, not a result.

1930-19931 event1 shown

A lithium route waits

A lithium route waits begins with lithium route appears. The result established the next question for the field.

1994-20181 event0 shown

Selectivity without trustworthy scale

Selectivity without trustworthy scale begins with high-pressure selectivity reaches 59%. The result established the next question for the field.

2019-20212 events1 shown

Verification before records

Verification before records moved the field from false positives confronted to gas diffusion raises the rate. The results narrowed the next question without closing it.

2020
Gas diffusion raises the rate
A non-aqueous gas-diffusion cathode reached 8.8 ± 1.4 mA/cm² ammonia partial current and 35 ± 6% Faradaic efficiency.
2022-20243 events2 shown

From tiny cells to continuous flow

From tiny cells to continuous flow moved the field from nearly all current selects ammonia to continuous ambient-pressure flow. The results narrowed the next question without closing it.

2022
Nearly all current selects ammoniaExperiment
A 0.15 cm² nickel-wire experiment reported 150 ± 20 nmol/s/cm² with current-to-ammonia efficiency close to 100%.
2022
A commercial rate is modeled
A techno-economic model found that sub-$1/kg ammonia requires more than 400 mA/cm² ammonia partial current, over 30% energy efficiency and several years of operating life.
2023
Continuous ambient-pressure flowExperiment
At 1 bar, a 25 cm² flow cell reached 61 ± 1% Faradaic efficiency but only 13 ± 1% full-cell energy efficiency at 6 mA/cm² total current.
2025-20293 events0 shown

The energy and integration test

The energy and integration test moved the field from lithium's efficiency ceiling is quantified to whole-cell energy use remains extreme. The results narrowed the next question without closing it.

2025
Lithium's efficiency ceiling is quantified
An energy analysis estimated a roughly 28% theoretical maximum energy efficiency for lithium- or calcium-mediated systems because electrodepositing the metal requires a large overpotential.
2026
MACAROON scale-up project starts
A Vinnova-backed project began work toward a 400 cm² flow cell, explicitly listing its performance values as targets rather than results.
2026
Whole-cell energy use remains extremeWe are here
Pulsed laboratory configurations reported 402.96 and 709.52 MWh/t NH3, corresponding to 1.37% and 0.78% production energy efficiency.
2021-20293 events2 shown

Events outside the declared eras

Events outside the declared eras moved the field from a proton shuttle improves output to integrated-cell target comes due. The results narrowed the next question without closing it.

2021
A proton shuttle improves output
A phosphonium shuttle delivered 53 ± 1 nmol/s/cm² at 69 ± 1% Faradaic efficiency under 19.5 bar nitrogen and 0.5 bar hydrogen.
2024
Continuous operation reaches 300 hoursExperiment
A 25 cm² flow cell ran for 300 hours at 1 bar and room temperature with 64 ± 1% Faradaic efficiency; it remained a laboratory reactor, not a pilot plant.
2029
Integrated-cell target comes dueExperimentTarget
MACAROON targets 300 mA/cm², 95% Faradaic efficiency, 25% energy efficiency, 500 hours and 24 g/h in a 400 cm² flow cell.
— end of record · 13 shown, 0 hidden —
13 events · below the TODAY rule = scheduled, not done
03 · The data behind the verdict

Why the meters read the way they do

The learning curves and comparisons that justify each threshold's percentage. Every series is measured, with the source event linked in the timeline above.

Four records do not make one reactor.Only 1 of 4 displayed benchmarks is met; no single reactor carries all four records.One row = one performance dimension · observed result vs target · linear or log scale per row · 2020–2029One row = one result from a separate experiment · solid bar and dot = observed · hollow dashed rail = model or programme target · linear or log scale per row · 2020–2029
Electrochemical ammonia performance frontierFour separate laboratory records in this dossier are compared with their relevant target: 38.4 versus 400 milliamperes per square centimetre ammonia partial current; 99 versus 90 percent Faradaic efficiency; 300 versus 500 continuous hours; and 13 versus 60 percent full-cell energy efficiency. None of the shown reactors demonstrated all four results together.NH₃ partial current2024 · 300-hour flow run · derived38.4 mA/cm²400 mA/cm²not achievedlog scaleFaradaic efficiency2022 · 0.15 cm² nickel wireclose to 100%≥90%threshold passed in this testlinear scaleContinuous duration2024 · 25 cm² flow cell300 h500 hnot achievedlog scaleFull-cell energy efficiency2023 · continuous flow at 1 bar13%60%not achievedlinear scale
Nature · DTU · Vinnova · ACS Energy Letters · AS OF JUL 2026
Technical notes

Read the evidence more closely

Definitions, system boundaries and experimental caveats behind the headline record.

01Selectivity is not system efficiency

Faradaic efficiency counts the fraction of charge that forms ammonia. It does not include the voltage penalty, gas preparation, solvent circulation, metal and proton-donor losses, separation or balance-of-plant loads. In the 2023 flow cell, 61% Faradaic efficiency corresponded to 13% full-cell energy efficiency.

02The lithium route carries a thermodynamic penalty

A 2025 analysis estimated a roughly 28% maximum energy efficiency for lithium- or calcium-mediated synthesis because electrodepositing either metal requires a very negative potential. It cites 60% as the US DOE technical-system target, so catalyst and reactor improvements alone may not close the route-level gap.

03The 2024 frontier is grams, not tonnes

The 25 cm² continuous-flow experiment is important evidence of solvent and reactor durability, but it remains a laboratory cell. Its current density, area and production scale cannot be described as commercial ammonia output.

04Nitrate-to-ammonia is a different problem

This dossier tracks reduction of molecular nitrogen, N2. Results starting from nitrate, nitrite or other activated nitrogen feedstocks are excluded because they do not demonstrate breaking the N≡N bond or sourcing nitrogen directly from air.

04 · What it unlocks

If the remaining tests pass

Downstream capabilities, drawn dashed because they depend on results not yet in.

Electrochemical AmmoniaDistributed fertilizer productionmake ammonia nearer farms with modular equipment instead of relying only on giant centralized plantsFlexible renewable chemical loadsturn variable wind and solar power into a storable chemical when electricity is abundantLower-carbon nitrogen feedstocksreduce emissions from ammonia used in fertilizer, chemicals and possible future fuels
05 · Sources

Where every number comes from

11 sources — every figure on this page traces to one.