LCOE Comparison Calculator

The levelized cost of energy converts a plant's lifetime costs into a single constant price per unit of output that would exactly recover them. The capital recovery factor does the conversion: r times one plus r raised to n, divided by the quantity one plus r raised to n minus one, where r is the discount rate and n the plant lifetime in years. Multiplying total capital cost by this factor yields an equivalent annual capital charge, which is added to annual operations and maintenance spending and divided by annual generation in megawatt-hours. Because capital is annuitized, LCOE is extremely sensitive to the discount rate for technologies whose costs are almost entirely upfront. Moving from 4 to 8 percent on a 25-year solar plant raises the capital recovery factor from about 0.0640 to about 0.0937, close to a 50 percent increase in the capital component. Capacity factor enters through the denominator, with typical annual values of 15 to 25 percent for utility solar, 25 to 45 percent onshore wind, 35 to 55 percent offshore wind, and 85 to 93 percent for nuclear. The metric deliberately excludes system integration costs such as firming capacity, storage, transmission reinforcement, and curtailment, so comparing a dispatchable plant with a variable one on LCOE alone understates the true system cost of the variable resource.

Annualizing a capital sum into a uniform charge is a technique from engineering economy, codified in Eugene Grant's Principles of Engineering Economy, first published in 1930 and used for decades to compare public works alternatives. Electric utilities under cost-of-service regulation already computed a fixed charge rate to translate rate base into an annual revenue requirement, so the ingredients of levelized costing existed well before the term itself became standard. Systematic cross-technology comparison arrived with the energy debates of the late 1970s and 1980s. The Electric Power Research Institute's Technical Assessment Guide gave US utilities standardized cost and performance assumptions, and the International Energy Agency together with the OECD Nuclear Energy Agency began publishing Projected Costs of Generating Electricity in 1983, a series appearing roughly every five years that made LCOE the common currency of international energy policy. The US Energy Information Administration added levelized cost estimates to its Annual Energy Outlook, and the investment bank Lazard has published an annual Levelized Cost of Energy analysis since 2007 that is widely cited in the press. IRENA's cost database later documented the collapse in renewable costs, reporting that the global weighted-average LCOE of utility-scale solar photovoltaics fell by roughly 90 percent between 2010 and 2023.