METHODOLOGICAL NOTES

This 2021 report is the second edition of the Renewables in Cities Global Status Report. Readers can see the previous REC edition for additional details.

Most 2019 and 2020 datai for national and global capacity, output, growth and investment provided in this report are preliminary. Where necessary, information and data that are conflicting, partial or older are reconciled by using reasoned expert judgment. Endnotes provide additional details, including references, supporting information and assumptions where relevant.

Each REC edition draws from thousands of published and unpublished references, including: official government sources; reports from international organisations and industry associations; input from the REN21 community, including questionnaires submitted by regional and technology contributors as well as feedback from several rounds of formal and informal reviews; additional personal communications with scores of international experts and special advisors, including an international advisory committee created specifically to support the production of each report; and a variety of electronic newsletters, news media and other sources.

Much of the data found in the REC is built from the ground up by the authors with the aid of these resources. Other data, often very specific and narrow in scope, come more-or-less prepared from third parties. The REC attempts to synthesise these data points into a collective whole for the focus years.

The REC endeavours to provide the best data available in each edition; as such, data should not be compared with the previous version of this report to ascertain year-by-year changes.

NOTE ON ESTABLISHING RENEWABLE ENERGY SHARES OF TOTAL FINAL ENERGY CONSUMPTION (TFEC)

For methodology related to calculating renewable energy shares of TFEC see methodological notes in REN21’s Renewables 2020 Global Status Report.

DEFINITION OF HEATING AND COOLING AND THERMAL APPLICATIONS

In the REC, the term “heating and cooling” refers to applications of thermal energy including space and water heating, space cooling, refrigeration, drying and industrial process heat, as well as any use of energy other than electricity that is used for motive power in any application other than transport. In other words, thermal demand refers to all end-uses of energy that cannot be classified as electricity demand or transport.

OTHER NOTES

This report includes data on projects, policies and other information prior to 31 December 2020. Editorial content of this report closed by 31 January 2021. Data provided for 2020 in the figures, tables and reference tables are as of the end of 2020, unless indicated otherwise. Growth rates in the REC are calculated as compound annual growth rates (CAGR) rather than as an average of annual growth rates. All exchange rates in this report are as of 31 December 2020 and are calculated using the OANDA currency converter (http://www.oanda.com/currency/converter). Corporate domicile, where noted, is determined by the location of headquarters.

iFor information on city-level renewable energy data and related challenges, see Box 1 on Page 30.i