Introduction and general considerations
Cost datasets list investment costs, fuel costs, variable and fixed operational and maintenance (VOM and FOM) costs of energy conversion and transmission technologies. They may also contain emission costs.
Typically they provide an analysis of historical costs and project into the future (e.g. 2030, 2050) with appropriate uncertainty bands. Projections must be treated with caution given that the costs of some technologies (solar, offshore wind and batteries) are changing fast.
The databases have very different scope, with some covering only renewable technologies, while others include all generation, heating and storage technologies.
Cost datasets by origin
Danish Energy Agency (DEA) and Energinet.dk
https://ens.dk/service/fremskrivninger-analyser-modeller/teknologikataloger/teknologikatalog-produktion-af-el
Last updated 2018. Includes generation, heating and storage technologies. Most information is also in English. Projections for 2020, 2030 and 2050.
National Renewable Energy Laboratory (NREL), US
http://www.nrel.gov/analysis/tech_cost_data.html
"Recent cost estimates for distributed generation (DG) renewable energy technologies are available across capital costs, operations and maintenance (O&M) costs, and levelized cost of energy (LCOE). Use the tabs below to navigate the charts. The LCOE tab provides a simple calculator for both utility-scale and DG technologies that compares the combination of capital costs, O&M, performance, and fuel costs. If you are seeking utility-scale technology cost and performance estimates, please visit the Transparent Cost Database website for NREL's information regarding vehicles, biofuels, and electricity generation."
German Renewable Energy Law (EEG) experience report (Erfahrungsbericht)
https://www.erneuerbare-energien.de/EE/Redaktion/DE/Downloads/bmwi_de/bericht-eeg-7-wind-auf-see.pdf?__blob=publicationFile&v=6
DIW Current and Prospective Costs of Electricity Generation until 2050
https://www.diw.de/sixcms/detail.php?id=diw_01.c.424588.de
Last updated 2013. Focuses on electricity generation. Projections up to 2050.