What is the carbon footprint of a wind turbine?
About 11 g CO₂e per kWh over its life for onshore wind (IPCC median), against 820 g for coal. A modern 6 MW turbine embodies roughly 2,700 t CO₂e, mostly steel and concrete, and its maker puts energy payback at 6.5 months.
A wind turbine burns no fuel, so its carbon footprint is almost entirely in the making: the steel tower and nacelle, the concrete foundation, the glass-fibre blades, the cables and the crane work to put it up. That footprint is real — a few thousand tonnes of CO₂e for a large modern turbine — but it is spread over twenty or more years of output. Per kilowatt-hour, wind is among the lowest-carbon electricity there is. This page gives the per-kWh figure, the per-turbine figure behind it, where the emissions come from, and how quickly a turbine pays them back.
The footprint per kilowatt-hour
The standard way to compare power sources is lifecycle emissions per kilowatt-hour: everything emitted to build, run and dismantle a plant, divided by all the electricity it produces. The IPCC’s Fifth Assessment Report compiled hundreds of studies into one table, and it remains the reference most methodologies cite.
| Technology | Min | Median | Max |
|---|---|---|---|
| Coal — pulverised | 740 | 820 | 910 |
| Gas — combined cycle | 410 | 490 | 650 |
| Solar PV — utility | 18 | 48 | 180 |
| Nuclear | 3.7 | 12 | 110 |
| Wind — offshore | 8.0 | 12 | 35 |
| Wind — onshore | 7.0 | 11 | 56 |
Median lifecycle intensities, IPCC AR5 Annex III Table A.III.2; the wind and solar medians render live from MasterBrain. Single-turbine figure: Vestas, LCA of Electricity Production from an onshore EnVentus V162-6.2 MW, low-wind site, 20-year life.
Onshore wind’s median is about seventy-five times lower than coal’s and roughly forty-five times lower than gas. The newest large turbines come in lower still: Vestas’s externally reviewed assessment of its V162-6.2 MW puts it at 6.2 g CO₂e per kWh, because bigger rotors on taller towers harvest far more energy from each tonne of material. The IPCC figures are older and span a wider range of machines and sites, which is why the maximum stretches to 56 g.
The footprint of one turbine
Turbine makers increasingly report the total, not just the per-kWh figure. For the V162-6.2 MW, Vestas gives 430 tonnes CO₂e per MW for the complete wind plant over its life cycle, and 313 tonnes per MW for the turbine alone. For one 6.2 MW turbine that is about 2,670 tonnes including its share of the foundations, cables and substation, or about 1,940 tonnes for the machine itself.
| Part | Mass per turbine | Mostly |
|---|---|---|
| Turbine (tower, nacelle, rotor) | ≈ 805 t | Steel and iron ≈ 693 t (86%); glass fibre, polymers, copper |
| Foundation | ≈ 2,580 t | Concrete ≈ 2,454 t; reinforcing steel ≈ 127 t |
By mass, a wind plant is mostly concrete; by carbon, the steel matters at least as much. Steel’s footprint per tonne is many times concrete’s — see What is the carbon footprint of steel? — and a turbine tower and nacelle are hundreds of tonnes of it. That is why the route and recycled content of the steel are the biggest single levers on a turbine’s footprint.
Where the emissions come from
Lifecycle assessments split a turbine’s footprint into stages. Vestas’s assessment, which follows ISO 14040 and 14044, finds that the production phase and the end-of-life phase dominate its environmental impacts; operation contributes little because there is no fuel.
- Materials and manufacturing — steel and iron for the tower, nacelle and hub; glass-fibre composites for the blades; copper and electronics; concrete and reinforcing steel for the foundation. This is the bulk of the footprint.
- Transport and installation — moving very large components to site and erecting them with heavy cranes or, offshore, installation vessels.
- Operation and maintenance — service trips and replacement parts over the turbine’s life. Small for onshore wind; larger offshore, where every visit needs a vessel.
- End of life — dismantling, plus a credit for the metals that are recycled. Around 87% of a Vestas turbine is metal, much of it recyclable; composite blades are harder to recycle.
The IPCC table makes the same point another way. For wind, it reports zero direct emissions from operation; the whole median of 11 to 12 g sits in infrastructure and supply chain. Offshore turbines carry more steel in their foundations and more vessel work over their life, but they also generate more, which is why the two medians end up almost the same.
A wind turbine’s emissions are paid up front and then not added to. Every year it runs after paying them back is close to carbon-free output.
How fast a turbine pays back its carbon
There are two ways to express payback, and they answer different questions.
- Energy payback — how long the turbine takes to generate as much energy as went into making and maintaining it. Vestas reports a break-even of 6.5 months for the V162-6.2 MW at a low-wind site.
- Carbon payback — how long it takes to avoid as much CO₂e as it embodies, which depends on the grid it displaces. A cleaner grid means a longer carbon payback, because each kilowatt-hour of wind avoids less.
For carbon payback, divide the turbine’s lifecycle footprint by the emissions its output avoids each year. On today’s UK grid average of 0.131 kg CO₂e per kWh [GreenCalculus grid.gbr.electricity.location_based · DEFRA 2026 'UK electricity'!E25 · v2026.237], the example turbine below pays back in under a year; on the US average of 0.350 kg CO₂e per kWh [GreenCalculus grid.usa.national.location_based · EPA EGRID 2023 'US23'!X3], in around four months. The renewable vs grid carbon payback calculator runs the same arithmetic for your own site and grid.
Why published figures vary
Search for the carbon footprint of a wind turbine and you will find anything from about 5 to more than 50 g CO₂e per kWh. Most of the spread comes from a handful of assumptions:
| Assumption | Lower figure | Higher figure |
|---|---|---|
| Wind resource and capacity factor | Windy site, high output per MW | Low-wind site, low output per MW |
| Turbine size and age | Large modern rotor on a tall tower | Older, smaller machines |
| Lifetime assumed | 25–30 years | 20 years |
| End-of-life recycling credit | Credit for recycled steel and copper | No credit, or landfill of blades |
| Foundation and site | Shallow foundation, short grid connection | Deep piled or offshore foundation, long cable |
| Manufacturing energy | Low-carbon steel and electricity in the supply chain | Coal-based steel and electricity |
The output is the denominator, so wind resource matters as much as materials: the same turbine on a site with twice the output has half the per-kWh footprint. Always check which wind class, lifetime and boundary a figure assumes before comparing it with another. For grid-average intensities to compare against, see grid electricity emission factors; for the reference values GreenCalculus uses for renewables, see renewable generation reference values.
Worked example: one 6.2 MW turbine
Inputs from Vestas’s LCA: 430 t CO₂e per MW for the complete plant, 6.2 MW per turbine, 21,568 MWh per turbine per year at a low-wind site, 20-year life. Grid factors are the UK and US averages at the time of writing. Illustrative.
| Step | Calculation | Result |
|---|---|---|
| Lifecycle footprint per turbine | 430 t × 6.2 MW | 2,666 t CO₂e |
| Lifetime output | 21,568 MWh × 20 yr | 431,360 MWh |
| Footprint per kWh | 2,666,000 kg ÷ 431,360,000 kWh | 6.2 g CO₂e/kWh |
| Carbon payback, UK grid | 2,666 t ÷ (21,568 MWh × 0.131 t/MWh) | 0.94 yr ≈ 11 months |
| Carbon payback, US grid | 2,666 t ÷ (21,568 MWh × 0.350 t/MWh) | 0.35 yr ≈ 4 months |
The per-kWh result reproduces Vestas’s published 6.2 g, which is a useful check that the inputs are consistent. Over 20 years on the UK grid the turbine avoids about 56,500 t CO₂e — around twenty-one times what it took to build. The carbon payback lengthens as the grid it displaces gets cleaner; the energy payback does not.
Frequently asked questions
For a modern 6.2 MW onshore turbine, Vestas reports 430 tonnes CO₂e per MW over the full life cycle of the wind plant, or about 2,670 tonnes per turbine including its share of foundations and grid connection. The turbine alone is 313 tonnes per MW, about 1,940 tonnes. Most of it comes from steel, concrete and composite manufacturing.
Usually under a year. Vestas reports an energy break-even of 6.5 months for its V162-6.2 MW at a low-wind site. Carbon payback depends on the grid the turbine displaces: about 11 months against the UK average grid and about 4 months against the US average in the worked example on this page.
On the IPCC’s lifecycle medians, yes: onshore wind is 11 g CO₂e per kWh and offshore wind 12 g, against 48 g for utility-scale solar PV and 41 g for rooftop. Both are a small fraction of gas at 490 g and coal at 820 g. Newer solar modules and newer turbines both sit below these older medians.
Only marginally. Offshore turbines need more steel in their foundations and more vessel work over their life, but they generate more electricity, so the IPCC lifecycle medians are almost the same: 12 g CO₂e per kWh offshore against 11 g onshore.
About 11 g CO₂e per kWh over its life for onshore wind, on the IPCC median, and 6.2 g for a modern 6.2 MW Vestas turbine. In total, such a turbine embodies roughly 2,700 tonnes CO₂e, mostly from its steel and concrete, and recovers the energy used to make it in about six and a half months.