Technical Limitations

This website explains detailed assumptions that are essential to appropriate interpretation of the ATB data. We recommend familiarizing yourself with the website documentation before using ATB data. The following summary of technical limitations does not substitute for the more complete documentation. Contact us if you have questions.

The purpose of the ATB is to provide CAPEX, O&M, and capacity factor estimates for Base Year (2021) and future year projections representing three levels of technical innovation (conservative, moderate, and advanced) for use in electric sector models.

The R&D Only cases are intended to reflect fundamental technology changes over time — not short-term market variations in pricing, not changes in interest rates or other project finance elements, and not macroeconomic influences such as commodity price fluctuations. These cases attempt to estimate the potential effects of technology innovation across the renewable electricity generation technologies under comparable levels of probability. This is inherently uncertain.

The Market + Policies Case approximate the costs of electricity generation plants with Independent Power Producer financial terms, covering the energy component of electric system planning and operation. Important items that are not included in these costs limit the validity of comparisons across technologies. The following table summarizes these limitations, identifies other analyses, tools, and data sets that are more complete sources for these items, and suggests applications that are affected by these limitations of the ATB.

Important Items Not Included ATB Renewable Electricity Generation Cost Estimates

Item Not Included in ATB	Alternative Source	Where This Limitation Applies
Spur lines beyond one mile to connect the plant to existing transmission infrastructure (for offshore wind, 30 km are included) Annual average operating costs Annual average energy production Impacts to the broader electric system based on output characteristics of the plant or distance from transmission infrastructure Capacity and flexibility services for electrical system reliability	Standard Scenarios based on the Regional Energy Deployment System (ReEDS) and Distributed Generation Market Demand Model (dGen) models includes electrical system impacts and transmission infrastructure requirements	Estimates of relative technology cost and value; Power system capacity expansion modeling
Site-specific renewable energy resource estimates	Resource Assessment	Detailed site-specific resource analyses and regional resource analyses based on multiple specific sites
Generation technology design variations that account for site-specific resource Geographic variation in the cost of labor, materials, and other inputs to generation plant construction.	Standard Scenarios based on the ReEDS and dGen models; System Advisor Model	Detailed site-specific technology cost analyses and regional technology analyses based on multiple specific sites
Financial metrics such as annual cash flow, net present value, and rate of return.	System Advisor Model	ATB CAPEX, O&M, and capacity factor may support calculation of other financial metrics, but the user may need to provide additional assumptions. The System Advisor Model includes cash flow.
Full component-level comparisons with other data sources		ATB provides some of these comparisons. Comparisons CAPEX, O&M, and capacity factor are preferable to LCOE comparisons (see LCOE for limitations).