How to calculate LCOE and know when a project actually beats the market price

In late 2023, a US utility signed a solar power purchase agreement (PPA, a long-term contract to buy electricity at a fixed price) at roughly $30 to $35 per megawatt-hour (MWh), a price that made headlines because wholesale power in that region was trading higher. Was that actually a good deal, or just a good headline? To answer that, you need one number: LCOE.

What LCOE actually measures

Levelized Cost of Energy (LCOE) is the average price per unit of electricity a project must earn over its lifetime to break even, covering construction, financing, operations, and an expected return. It is measured in $/MWh or €/MWh.

Think of it as the "all-in cost price" of a power plant, spread evenly across every MWh it will ever produce. If a project's contracted sale price beats its LCOE, it is expected to be profitable. If not, someone is losing money, or being subsidized.

The formula, in plain terms

$$

LCOE = \frac{\text{Total lifetime costs (discounted)}}{\text{Total lifetime energy output (discounted)}}

$$

More precisely:

$$

LCOE = \frac{\sum_{t=0}^{n} \frac{CapEx_t + OpEx_t}{(1+r)^t}}{\sum_{t=0}^{n} \frac{Energy_t}{(1+r)^t}}

$$

Where:

• CapExCapExCapital Expenditure (CapEx) is money spent to acquire, upgrade, or extend long-lived assets like equipment, property, or software that deliver value over multiple years.View full definition →: capital expenditure (turbines, panels, grid connection, construction)
• OpEx: operating expenditure (maintenance, land lease, insurance, asset management)
• r: discount rate, reflecting cost of capitalcost of capitalThe blended rate a company pays to finance itself through debt and equity. It sets the minimum return an investment must clear to create value.View full definition → and risk
• n: project lifetime in years
• Energy_t: MWh produced in year t

Discounting matters because $1 spent today is not equivalent to $1 spent in year 15. This is the same net-present-value logic used to value any long-lived investment.

Worked example: a hypothetical US onshore wind farm

Let's build one from scratch, using realistic 2024 to 2025 US benchmark ranges (all figures below are industry estimates, notably from NREL's Annual Technology Baseline, not project-specific quotes).

Assumptions for a 100 MW onshore wind farm:

• CapEx: ~$1,300/kW installed → $130 million total (NREL 2024 estimate, mid-range)
• OpEx: ~$28/kW-year → $2.8 million/year
• Capacity factor: 35% (share of theoretical maximum output actually generated; typical for good US wind sites)
• Lifetime: 25 years
• Discount rate: 7% (reflecting a blended cost of debt and equity, a rough proxy for weighted average cost of capital, WACC)

Step 1: Annual energy output

100 MW × 35% capacity factor × 8,760 hours/year ≈ 306,600 MWh/year

Step 2: Discounted lifetime output

Summing 306,600 MWh/year for 25 years at a 7% discount rate gives a present value of roughly 3.57 million MWh (using the standard annuity discount factor).

Step 3: Discounted lifetime costs

• CapEx (year 0): $130 million
• OpEx discounted over 25 years at 7%: $2.8 million × ~11.65 (annuity factor) ≈ $32.6 million
• Total discounted costs ≈ $162.6 million

Step 4: Divide

$$

LCOE = \frac{\$162.6\text{ million}}{3.57\text{ million MWh}} \approx \$45.5/\text{MWh}

$$

That lands close to real-world US onshore wind LCOE estimates of roughly $30 to $50/MWh (NREL, Lazard's Levelized Cost of Energy Analysis, 2024 edition, both estimates). Good sign the math holds together.

Now the solar PPA test

Back to that 2023 US solar PPA at ~$30 to $35/MWh. Utility-scale solar LCOE estimates for the US in that period ranged roughly $24 to $40/MWh depending on region, financing cost, and tax credit treatment (Lazard 2023/2024 estimates; Lazard LCOE report).

Here is the catch: US solar LCOE is heavily shaped by federal tax incentives, notably the Investment Tax Credit (ITC) under the Inflation Reduction Act of 2022, which can cover 30% or more of CapEx. Strip that out, and unsubsidized LCOE would be meaningfully higher, often estimated in the $40 to $55/MWh range.

So a $30 to $35/MWh PPA only "beats the market" once you factor in the tax credit reducing the developer's effective CapEx. Without it, that price could be marginal or loss-making. This is why comparing a headline PPA price to a generic LCOE benchmark without checking subsidy assumptions is a common analytical mistake.

The judgment call: a PPA price above LCOE signals a bankable project. A PPA priced near or below unsubsidized LCOE signals the developer is either extremely efficient, backed by cheap financing, banking on incentives, or taking a strategic loss to build market sharemarket shareThe percentage of total industry sales your company captures in a given period. It measures competitive position relative to rivals in a defined market.View full definition →.

Europe's comparison point

In Europe, offshore wind LCOE estimates for 2024 run roughly €50 to €85/MWh depending on country and seabed conditions (estimates from IEA's World Energy Outlook and industry sources), notably higher than US onshore wind due to construction complexity at sea and higher financing costs in some markets. Onshore wind and solar in Europe generally sit closer to €30 to €60/MWh (estimates).

Europe's benchmark reference price is often the day-ahead wholesale power price on exchanges like EPEX Spot or Nord Pool, rather than a single PPA. A useful sanity check: if a project's LCOE sits comfortably below the multi-year average wholesale price for its market, it clears the bar without subsidy support.

Why LCOE has limits

LCOE is a cost benchmark, not a market price predictor. It ignores:

• Timing of output: solar produces at midday when prices are often lower (the "merchant risk" or cannibalization effect); a technology can have low LCOE but weak realized revenue.
• Grid and integration costs: transmission upgrades, curtailment (when output is reduced because the grid can't absorb it).
• Policy risk: subsidies can change; the ITC's future value depends on continued legislation.

Analysts increasingly pair LCOE with LCOE-adjusted metrics like "value-adjusted LCOE" or compare it against the actual captured price a plant earns in real-time markets. That is a more advanced topic, but knowing LCOE's blind spots is table stakes for reading any project pro forma.

Key Takeaways

• LCOE = discounted lifetime costs ÷ discounted lifetime energy output; it tells you the minimum price a project needs to break even, in $/MWh or €/MWh.
• US onshore wind LCOE estimates run roughly $30 to $50/MWh; US utility-scale solar roughly $24 to $40/MWh (Lazard, NREL estimates, 2023 to 2024). European offshore wind runs notably higher, roughly €50 to €85/MWh (estimates).
• Always check whether an LCOE or PPA price includes subsidies like the US Investment Tax Credit; unsubsidized figures can be substantially higher.
• A PPA price beating LCOE is a good signal but not proof of a good deal: check capacity factor assumptions, discount rate, and whether the comparison price is subsidized or merchant (market-exposed).
• Use LCOE as a first screen, then compare against real wholesale price benchmarks (EPEX Spot, Nord Pool, US regional ISOs like ERCOT or PJM) before judging a project as genuinely cost competitive.