Source weather data for building energy simulation programs
can be broken into two major classes: historical data
and typical weather years. Historical data is just
“real” data: usually measured (but sometimes modeled) data
from a particular location for a given period of record.
Typical years are ersatz years assembled to match the long
term data from a particular location using a particular
statistical measure. Typical data may also be “real” data but
may not be a contiguous year - the data may be comprised of
months from multiple years.
The primary source for historical weather data is the U.S.
National Climatic Data Center (NCDC) in Asheville, NC: http://www.ncdc.noaa.gov/. NCDC can provide
hourly historical data for thousands of locations around the
world. This data may not always be complete; data items or
periods of record may be missing.
In this document as well in many others, you will read
about a certain “data set” and you will also read about data
in a “certain” format - e.g., the TMY2 data set and the TMY2
data format. Simply stated, a data set refers to a set of data
files developed around a set of procedures for selection and
usually with a specific purpose for use. A data format is
merely the identification of data elements in a data file. In
the TMY2 example, the TMY2 data set was developed as described
below and the format of the data is usually called a TMY2
format.
Any data could be put into a TMY2 format, but it
wouldn’t necessarily be selected using the same procedures as
the TMY2 data set.
A highly reliable source of historical data for U.S.
locations is the Solar and Meteorological Surface
Observational Network (SAMSON) data set assembled by the
National Renewable Energy Laboratory (NREL) in Golden, CO: http://www.nrel.gov/. The SAMSON data set
contains a 30 year (1961 to 1990) period of record for 239
locations and are available from the NCDC.
SAMSON also describes a file format. Though no data from
the SAMSON data set are available for download in EPW format,
the weather conversion utility can read and process this file
format.
The TMY2 are data sets of hourly values of solar radiation
and meteorological elements for a 1-year period. Their
intended use is for computer simulations of solar energy
conversion systems and building systems to facilitate
performance comparisons of different system types,
configurations, and locations in the United States and its
territories. Because they represent typical rather than
extreme conditions, they are not suited for designing systems
to meet the worst-case conditions occurring at a location. The
data are available from the National Renewable Energy
Laboratory for download or on CD.
TMY3 files have somewhat replaced TMY2 files but all TMY2
files are available for download from the website.
The Solar and Wind Energy Resource Assessment (SWERA)
project, funded by the United Nations Environment Program, is
developing high quality information on solar and wind energy
resources in 14 developing countries. Currently typical year
hourly data are available for 156 locations in Belize, Brazil,
China, Cuba, El Salvador, Ethiopia, Ghana, Guatemala,
Honduras, Kenya, Maldives, Nicaragua, and Sri Lanka. The data
are available from the SWERA project web site. http://swera.unep.net/;
The SWERA format is very similar to the TMY2 format except:
WMO stations are used (6 character) in the header and 4 digit
years have been adopted in the data lines.
Culminating in the early 1980s, ASHRAE published their
“Weather Year for Energy Calculations” (WYEC) hourly weather
files for 51 US and Canadian locations. These files were
intended to support the then growing interest in computer
simulation of energy use in buildings. In the late 1980s, a
major revision was initiated - this included the addition of
26 Typical Meteorological Year (TMY) hourly weather files to
the original WYEC data set and a number of improvements.
The work of revising and improving the WYEC data base was
performed by at the National Renewable Energy Laboratory
(NREL) as part of the Solar Radiation Resource Assessment
Program (SRRAP), during the period 1989 through 1993. Richard
Perez, at the State University of New York at Albany –
Atmospheric Sciences Research Center provided a substantial
contribution to this work. The resulting set of 77 revised and
corrected hourly weather files are referred to as WYEC Version
2 or “WYEC2” data set.
The WYEC2 format is used as the format for several other
data sets. The WYEC2 data set, however, was not made available
for download though, of course, those files can be read if
desired with the EnergyPlus Weather Converter utility.
Canadian
Weather for Energy Calculations (CWEC)[LINK]
Produced by Numerical Logics in collaboration with
Environment Canada and the National Research Council of
Canada, the CWEC were derived using a methodology similar to
the TMY2 and TMY. CWEC hourly files represent weather
conditions that result in approximately average heating and
cooling loads in buildings. The National Energy Code of Canada
requires the use of a CWEC file representative of a location
when the performance path and customized design calculations
are chosen as the means of building energy consumption
compliance. The CWEC follow the ASHRAE WYEC2 format and were
derived from the Canadian Energy and Engineering Data Sets
(CWEEDS) of hourly weather information for Canada from the
1953-1995 period of record.
The 80 CWEC files contain hourly weather observations
representing an artificial one-year period specifically
designed for building energy calculations. All 80 locations in
the CWEC data set are available for download in EnergyPlus
weather format.
International
Weather for Energy Calculations (IWEC)[LINK]
The IWEC are the result of ASHRAE Research Project 1015
conducted by Numerical Logics and Bodycote Materials Testing
Canada for ASHRAE Technical Committee 4.2 Weather Information.
The IWEC data files are ‘typical’ weather files suitable for
use with building energy simulation programs for 227 locations
outside the USA and Canada.
The files are derived from up to 18 years of DATSAV3 hourly
weather data originally archived at the U S National Climatic
Data Center. The weather data is supplemented by solar
radiation estimated on an hourly basis from earth-sun geometry
and hourly weather elements, particularly cloud amount
information. The IWEC CD-ROM is available from ASHRAE.
The Department of Energy has licensed the IWEC data from
ASHRAE. Our license with ASHRAE allows us to: “Distribute
versions of the individual IWEC files in converted format
suitable for EnergyPlus (EPW). Make the EnergyPlus versions of
the IWEC files available to users at no cost via this
EnergyPlus web site.” All 227 locations in the IWEC data set
are available for download in EnergyPlus weather format.
The IWEC source data is © 2001 American Society of Heating,
Refrigerating and Air-Conditioning Engineers (ASHRAE), Inc.,
Atlanta, GA, USA. http://www.ashrae.org/ All rights reserved as
noted in the License Agreement and Additional Conditions.
IWEC also describes a data format, very similar to the TMY2
data format.
Typical
Meteorological Year (TMY)[LINK]
Data for 230 locations in the USA plus four locations in
Cuba, Marshall Islands, Palau, and Puerto Rico, derived from a
1948-1980 period of record. Many of the locations in the TMY
data set were subsequently updated by the TMY2.
Similar to the TMY2, the TMY are data sets of hourly values
of solar radiation and meteorological elements for a 1-year
period. Their intended use is for computer simulations of
solar energy conversion systems and building systems to
facilitate performance comparisons of different system types,
configurations, and locations in the United States and its
territories. Because they represent typical rather than
extreme conditions, they are not suited for designing systems
to meet the worst-case conditions occurring at a location. The
data are available for purchase from the National Climatic
Data Center.
All TMY locations are available for download in EnergyPlus
weather format.
TMY also describes a data format.
California Climate
Zones 2 (CTZ2)[LINK]
Updated weather data for 16 California climate zones for
use to demonstrate compliance with Title 24 with approved
building energy simulation programs. All 16 CTZ2 weather files
are available for download in EnergyPlus weather format. The
original source data is available from the California Energy
Commission. These source data files are described using the
WYEC2 format.
Solar
and Wind Energy Resource Assessment (SWERA)[LINK]
The Solar and Wind Energy Resource Assessment (SWERA)
project, funded by the United Nations Environment Program, is
developing high quality information on solar and wind energy
resources in 13 developing countries. Currently typical year
hourly data are available for 48 locations in Belize, Cuba, El
Salvador, Guatemala, Honduras, Maldives, Nicaragua, and Sri
Lanka. The data are available from the SWERA project web site.
SWERA plans to release new data for Brazil, Ethiopia, Ghana,
Kenya, and Nepal over the coming few months. These source data
files are described using the SWERA format.
Spanish
Weather for Energy Calculations (SWEC)[LINK]
Originally developed for use with Calener, a new program
for building energy labelling in Spain, these weather files
cover all 52 Spanish provincial capitals. Calener was
developed by the Grupo de Termotecnia of the Escuela Superior
de Ingeneiros in Seville for the Spanish Government. The
weather files were synthetically generated using Climed
(Portuguese software developed by Ricardo Aguiar) from mean
monthly data coming from the Spanish Meteorological National
Institute. These weather files were converted from the DOE-2
binary to EnergyPlus format and include constant wind speeds
of 6.7 m/s.
For more information on these weather files, contact:
Profesor Luis Pérez-Lombard (lpl@tmt.us.es)
Escuela Superior de Ingenieros
Italian
Climatic data collection “Gianni De Giorgio” (IGDG)[LINK]
Developed for use in simulating renewable energy
technologies, this set of 66 weather files is based on a
1951-1970 period of record. The data were created by Professor
Livio Mazzarella, Politecnico di Milano, and is named in honor
of Gianni de Giorgio.
Chinese Typical
Year Weather (CTYW)[LINK]
Developed for use in simulating building heating and air
conditioning loads and energy use, and for calculating
renewable energy utilization, this set of 57 weather files is
based on a 1982-1997 period of record with data obtained from
the U. S. National Climatic Data Center. The data were created
by Prof. ZHANG Qingyuan of Tsukuba University Japan, in
collaboration with Joe Huang of Lawrence Berkeley National
Laboratory. The original typical year weather files are
contained in: Zhang Qingyuan and Joe Huang. 2004. Chinese
Typical Year Weather Data for Architectural Use (in Chinese).
ISBN 7-111-14810-X. Beijing: China Machine Press. Available
from: China Machine Press; No. 22 Baiwanzhuang Dajie; Beijing,
CHINA 100037.
The CTYW files are no longer available for download from
the web site.
INETI Synthetic
data for Portugal[LINK]
Two weather files for Portugal developed by Ricardo Aguiar
of Instituto Nacional de Engenharia, Tecnologia e Inovação
(INETI). Synthetic data set based on spatially interpolation
of public climatic data published by Instituto de Meteorologia
1951-80 combined with INETI owned data and other freely
available data sources. INETI has granted DOE permission to
distribute versions of the individual INETI files in converted
format suitable for EnergyPlus (EPW) and make those files
available to users at no cost via this EnergyPlus web
site.
The INETI synthetic data are © 2005 Instituto Nacional de
Engenharia, Tecnologia e Inovação, Lisboa, Portugal. http://www.ineti.pt
ISHRAE India
Weather Data Files (ISHRAE)[LINK]
Developed for use in simulating building heating and air
conditioning loads and energy use, and for calculating
renewable energy utilization, this set of 58 weather files was
developed by the Indian Society of Heating, Refrigerating, and
Air-Conditioning Engineers (ISHRAE). The source data are
Copyright 2005 ISHRAE. ISHRAE has made these data available to
DOE under license for use at no cost to the EnergyPlus user
community.
City
University of Hong Kong (CUHK) Data Set[LINK]
CityUHK-45007 – WMO#450070 Typical year file Hong Kong
originally in IWEC format spreadsheet jointly developed by Dr
TT Chow and ALS Chan of the City University of Hong Kong
supported by a CERG grant from the Research Grants Council of
the Hong Kong Special Administrative Region of China. Solar
radiation measured from observatory station at 22.32N 114.17’E
65m above mean sea level.
Chinese Standard
Weather Data (CSWD)[LINK]
Developed for use in simulating building heating and air
conditioning loads and energy use, and for calculating
renewable energy utilization, this set of 270 typical hourly
data weather files. These data were developed by Dr. Jiang Yi,
Department of Building
Science and Technology at Tsinghua University and China
Meteorological Bureau. The source data include annual design
data, typical year data, and extreme years for maximum
enthalpy, and maximum and minimum temperature and solar
radiation.
China Meteorological Bureau, Climate Information Center,
Climate Data Office and Tsinghua University, Department of Building
Science and Technology. 2005. China Standard Weather Data for
Analyzing Building
Thermal Conditions, April 2005. Beijing: China Building
Industry Publishing House, ISBN 7-112-07273-3 (13228). http://www.china-building.com.cn.
Kuwait
Weather Data from Kuwait Institute for Scientific Research
(KISR)[LINK]
Two weather files for Kuwait based on measured
meteorological data for Kuwait International Airport and
KISR’s coastal weather station. Provided by KISR in
spreadsheet format.
Egyptian
Weather for Energy Calculations (EWEC)[LINK]
Developed for standards development and energy simulation
by Joe Huang from data provided by National Climatic Data
Center for periods of record from 12 to 21 years, all ending
in 2003. Joe Huang and Associates, Moraga, California,
USA.
Israel weather data
(MSI)[LINK]
Weather data for Israel locations developed by Faculty of
Civil and Environmental Engineering, Technion - Israel
Institute of Technology, Haifa, Israel, from data provided by
the Israel Meteorological Service.
Representative
Meteorological Year (RMY) Australia Climatic Data[LINK]
RMY Australia Representative Meteorological Year Climate
Files Developed for the Australia Greenhouse Office for use in
complying with Building
Code of Australia. These data are licensed through ACADS BSG
Ltd for use by EnergyPlus users. For use in any other formats,
users must contact ACADS BSG Ltd for licensing
information.
The RMY data are © 2006 Commonwealth of Australia,
Department of the Environment and Water Resources, Australia
Greenhouse Office, Canberra, ACT, Australia. www.greenhouse.gov.au/buildings/code.html
(URL has since been removed, so replaced with a link on The
Internet Archive from 2007.) All intellectual property rights
reserved.
Iranian
Typical Meteorological Year (ITMY)[LINK]
Typical year weather files have been created for Tehran
from weather data for 1992 through 2003 published by the
Islamic Republic of Iran Meteorological Organization (IRIMO)
for Tehran Mehrabad. Developed for standards development and
energy simulation by Joe Huang, White Box Technologies.
New
Zealand National Institute of Water & Atmospheric Research
Ltd (NIWA)[LINK]
The New Zealand Energy Efficiency and Conservation
Authority (EECA) has developed a Home Energy Rating Scheme
(HERS) for New Zealand households based on software simulation
of energy loss and demand. The software requires hourly data
to represent the different climates zones around New Zealand,
especially for larger population centres. These climate data
consist of hourly records for an artificial year created from
twelve representative months.
Liley, J Ben, Hisako Shiona, James Sturman, David S Wratt.
2007. Typical Meteorological Years for the New Zealand Home
Energy Rating Scheme. Prepared for the Energy Efficiency and
Conservation Authority. NIWA Client Report: LAU2007- 02-JBL.
NIWA, Omakau, New Zealand.
Chartered
Institution of Building Services Engineers (CIBSE)[LINK]
The CIBSE, in association with the (UK) Met Office has
produced ‘Test Reference Years’ and ‘Design Summer Years’ for
14 UK locations for use with building energy simulation
software. The data sets are available in various formats,
including EnergyPlus/ESP-r. These data are NOT available on
the EnergyPlus web site. For further details, see:
www.cibse.org/index.cfm?go
= publications.view&PubID = 332&S1 = y&L1 =
0&L2 = 0
Meteonorm Data[LINK]
Meteonorm software can be used when there is no measured
data near the location for the simulation. Meteonorm
extrapolates hourly data from statistical data for a location.
Where statistical data aren’t available, Meteonorm
interpolates from other nearby sites. Generally a statistical
approach is a last resort – weather files generated from
statistics will not demonstrate the normal hour-to-hour and
day-to-day variability seen in measured data. Meteonorm
version 6 will directly write EPW files.
The data sets and formats described above are some of the
newest formats available for use with building simulation
programs. Source data comes in various formats. Typically the
files are ASCII, but the data items, units, item location, and
record length vary from format to format. NCDC can provide
historical data in a variety of formats: TD-3280, TD-3510,
TD-9950 (DATSAV2), TD-9956 (DATSAV3) and TD-1440 (CD144). The
EnergyPlus weather processor cannot process any of the types
directly.
Source
—————– —— ——– —————– ——– —— ————— ——————- ——– ——-
USA Canada Central America Africa Asia South America Southwest Pacific Europe Total
ETMY 11 11 IGDG 66 66 IMGW 61 61 INETI 2 2 ISHRAE 58 58
ITMY 1 1 IWEC 5 12 49 19 20 122 227 KISR 2 2 Los Alamos TMY2 1
1 MSI 4 4 NIWA 16 16 RMY 80 80 SWEC 2 50 52 SWERA 37 33 66 20
156 TMY 229 1 4 234 TMY2 235 1 1 237 TMY3 1011 7 2 1020 Totals
1476 0 51 58 176 39 123 305
: Summary of Downloadable Weather Data by Type
One other format worth mentioning is TRY. TRY is “test
reference year” data that did not include solar radiation
data. “Test Reference Year” is a term that usually denotes
selection of a specific year of “real” data based on some
statistical procedure. The original TRY data (TD-9706) was
based on an ASHRAE procedure to select the data from a “period
of record”. “The principle of the selection is to eliminate
years in the period of record containing months with extremely
high or low mean temperatures until only one year remains.”
The weather conversion utility cannot process data in “TRY”
format. However, many organizations develop data for reference
year data (e.g. European TRY, Moisture Reference Data).
Using a “definitions” file (see Description of “Def” input
file), the weather converter can process a wide range of data
formats. In the table above, both the GDG and CTYW weather
data was processed by a custom format approach.
Source weather data files may or may not contain solar
data. All of the files that can be processed by the EnergyPlus
Weather conversion utility contain solar data. The weather
processor will transfer this data to the EPW weather file and
the EnergyPlus simulation program will use it.
Historical weather data files in CD144 format do not
contain solar data nor is such data generally available for a
specific location and time period. In this case, ersatz solar
data must be generated from cloud cover and other data using
sky models and regression formulas. Currently, neither the
Weather Conversion utility nor the EnergyPlus program
synthesizes this data. However, the weather conversion utility
can use any two of the commonly recorded data (i.e. two of
Global Horizontal Radiation, Horizontal Diffuse Radiation and
Direct Normal (or Direct Horizontal) Radiation to calculate
the EnergyPlus primary solar data of Direct Normal and
Horizontal Diffuse Radiation values).
Source Weather Data Formats[LINK]
Source weather data for building energy simulation programs can be broken into two major classes: historical data and typical weather years. Historical data is just “real” data: usually measured (but sometimes modeled) data from a particular location for a given period of record. Typical years are ersatz years assembled to match the long term data from a particular location using a particular statistical measure. Typical data may also be “real” data but may not be a contiguous year - the data may be comprised of months from multiple years.
The primary source for historical weather data is the U.S. National Climatic Data Center (NCDC) in Asheville, NC: http://www.ncdc.noaa.gov/. NCDC can provide hourly historical data for thousands of locations around the world. This data may not always be complete; data items or periods of record may be missing.
Data Set vs. Data Format[LINK]
In this document as well in many others, you will read about a certain “data set” and you will also read about data in a “certain” format - e.g., the TMY2 data set and the TMY2 data format. Simply stated, a data set refers to a set of data files developed around a set of procedures for selection and usually with a specific purpose for use. A data format is merely the identification of data elements in a data file. In the TMY2 example, the TMY2 data set was developed as described below and the format of the data is usually called a TMY2 format.
Any data could be put into a TMY2 format, but it wouldn’t necessarily be selected using the same procedures as the TMY2 data set.
SAMSON Data Set/Format[LINK]
A highly reliable source of historical data for U.S. locations is the Solar and Meteorological Surface Observational Network (SAMSON) data set assembled by the National Renewable Energy Laboratory (NREL) in Golden, CO: http://www.nrel.gov/. The SAMSON data set contains a 30 year (1961 to 1990) period of record for 239 locations and are available from the NCDC.
SAMSON also describes a file format. Though no data from the SAMSON data set are available for download in EPW format, the weather conversion utility can read and process this file format.
TMY2 Data Set/Format[LINK]
The TMY2 are data sets of hourly values of solar radiation and meteorological elements for a 1-year period. Their intended use is for computer simulations of solar energy conversion systems and building systems to facilitate performance comparisons of different system types, configurations, and locations in the United States and its territories. Because they represent typical rather than extreme conditions, they are not suited for designing systems to meet the worst-case conditions occurring at a location. The data are available from the National Renewable Energy Laboratory for download or on CD.
TMY3 files have somewhat replaced TMY2 files but all TMY2 files are available for download from the website.
Solar and Wind Energy Resource Assessment (SWERA) Format[LINK]
The Solar and Wind Energy Resource Assessment (SWERA) project, funded by the United Nations Environment Program, is developing high quality information on solar and wind energy resources in 14 developing countries. Currently typical year hourly data are available for 156 locations in Belize, Brazil, China, Cuba, El Salvador, Ethiopia, Ghana, Guatemala, Honduras, Kenya, Maldives, Nicaragua, and Sri Lanka. The data are available from the SWERA project web site. http://swera.unep.net/;
The SWERA format is very similar to the TMY2 format except: WMO stations are used (6 character) in the header and 4 digit years have been adopted in the data lines.
WYEC2 Data Set/Format[LINK]
Culminating in the early 1980s, ASHRAE published their “Weather Year for Energy Calculations” (WYEC) hourly weather files for 51 US and Canadian locations. These files were intended to support the then growing interest in computer simulation of energy use in buildings. In the late 1980s, a major revision was initiated - this included the addition of 26 Typical Meteorological Year (TMY) hourly weather files to the original WYEC data set and a number of improvements.
The work of revising and improving the WYEC data base was performed by at the National Renewable Energy Laboratory (NREL) as part of the Solar Radiation Resource Assessment Program (SRRAP), during the period 1989 through 1993. Richard Perez, at the State University of New York at Albany – Atmospheric Sciences Research Center provided a substantial contribution to this work. The resulting set of 77 revised and corrected hourly weather files are referred to as WYEC Version 2 or “WYEC2” data set.
The WYEC2 format is used as the format for several other data sets. The WYEC2 data set, however, was not made available for download though, of course, those files can be read if desired with the EnergyPlus Weather Converter utility.
Canadian Weather for Energy Calculations (CWEC)[LINK]
Produced by Numerical Logics in collaboration with Environment Canada and the National Research Council of Canada, the CWEC were derived using a methodology similar to the TMY2 and TMY. CWEC hourly files represent weather conditions that result in approximately average heating and cooling loads in buildings. The National Energy Code of Canada requires the use of a CWEC file representative of a location when the performance path and customized design calculations are chosen as the means of building energy consumption compliance. The CWEC follow the ASHRAE WYEC2 format and were derived from the Canadian Energy and Engineering Data Sets (CWEEDS) of hourly weather information for Canada from the 1953-1995 period of record.
The 80 CWEC files contain hourly weather observations representing an artificial one-year period specifically designed for building energy calculations. All 80 locations in the CWEC data set are available for download in EnergyPlus weather format.
International Weather for Energy Calculations (IWEC)[LINK]
The IWEC are the result of ASHRAE Research Project 1015 conducted by Numerical Logics and Bodycote Materials Testing Canada for ASHRAE Technical Committee 4.2 Weather Information. The IWEC data files are ‘typical’ weather files suitable for use with building energy simulation programs for 227 locations outside the USA and Canada.
The files are derived from up to 18 years of DATSAV3 hourly weather data originally archived at the U S National Climatic Data Center. The weather data is supplemented by solar radiation estimated on an hourly basis from earth-sun geometry and hourly weather elements, particularly cloud amount information. The IWEC CD-ROM is available from ASHRAE.
The Department of Energy has licensed the IWEC data from ASHRAE. Our license with ASHRAE allows us to: “Distribute versions of the individual IWEC files in converted format suitable for EnergyPlus (EPW). Make the EnergyPlus versions of the IWEC files available to users at no cost via this EnergyPlus web site.” All 227 locations in the IWEC data set are available for download in EnergyPlus weather format.
The IWEC source data is © 2001 American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), Inc., Atlanta, GA, USA. http://www.ashrae.org/ All rights reserved as noted in the License Agreement and Additional Conditions.
IWEC also describes a data format, very similar to the TMY2 data format.
Typical Meteorological Year (TMY)[LINK]
Data for 230 locations in the USA plus four locations in Cuba, Marshall Islands, Palau, and Puerto Rico, derived from a 1948-1980 period of record. Many of the locations in the TMY data set were subsequently updated by the TMY2.
Similar to the TMY2, the TMY are data sets of hourly values of solar radiation and meteorological elements for a 1-year period. Their intended use is for computer simulations of solar energy conversion systems and building systems to facilitate performance comparisons of different system types, configurations, and locations in the United States and its territories. Because they represent typical rather than extreme conditions, they are not suited for designing systems to meet the worst-case conditions occurring at a location. The data are available for purchase from the National Climatic Data Center.
All TMY locations are available for download in EnergyPlus weather format.
TMY also describes a data format.
California Climate Zones 2 (CTZ2)[LINK]
Updated weather data for 16 California climate zones for use to demonstrate compliance with Title 24 with approved building energy simulation programs. All 16 CTZ2 weather files are available for download in EnergyPlus weather format. The original source data is available from the California Energy Commission. These source data files are described using the WYEC2 format.
Solar and Wind Energy Resource Assessment (SWERA)[LINK]
The Solar and Wind Energy Resource Assessment (SWERA) project, funded by the United Nations Environment Program, is developing high quality information on solar and wind energy resources in 13 developing countries. Currently typical year hourly data are available for 48 locations in Belize, Cuba, El Salvador, Guatemala, Honduras, Maldives, Nicaragua, and Sri Lanka. The data are available from the SWERA project web site. SWERA plans to release new data for Brazil, Ethiopia, Ghana, Kenya, and Nepal over the coming few months. These source data files are described using the SWERA format.
Spanish Weather for Energy Calculations (SWEC)[LINK]
Originally developed for use with Calener, a new program for building energy labelling in Spain, these weather files cover all 52 Spanish provincial capitals. Calener was developed by the Grupo de Termotecnia of the Escuela Superior de Ingeneiros in Seville for the Spanish Government. The weather files were synthetically generated using Climed (Portuguese software developed by Ricardo Aguiar) from mean monthly data coming from the Spanish Meteorological National Institute. These weather files were converted from the DOE-2 binary to EnergyPlus format and include constant wind speeds of 6.7 m/s.
For more information on these weather files, contact: Profesor Luis Pérez-Lombard (lpl@tmt.us.es) Escuela Superior de Ingenieros
Italian Climatic data collection “Gianni De Giorgio” (IGDG)[LINK]
Developed for use in simulating renewable energy technologies, this set of 66 weather files is based on a 1951-1970 period of record. The data were created by Professor Livio Mazzarella, Politecnico di Milano, and is named in honor of Gianni de Giorgio.
Chinese Typical Year Weather (CTYW)[LINK]
Developed for use in simulating building heating and air conditioning loads and energy use, and for calculating renewable energy utilization, this set of 57 weather files is based on a 1982-1997 period of record with data obtained from the U. S. National Climatic Data Center. The data were created by Prof. ZHANG Qingyuan of Tsukuba University Japan, in collaboration with Joe Huang of Lawrence Berkeley National Laboratory. The original typical year weather files are contained in: Zhang Qingyuan and Joe Huang. 2004. Chinese Typical Year Weather Data for Architectural Use (in Chinese). ISBN 7-111-14810-X. Beijing: China Machine Press. Available from: China Machine Press; No. 22 Baiwanzhuang Dajie; Beijing, CHINA 100037.
The CTYW files are no longer available for download from the web site.
INETI Synthetic data for Portugal[LINK]
Two weather files for Portugal developed by Ricardo Aguiar of Instituto Nacional de Engenharia, Tecnologia e Inovação (INETI). Synthetic data set based on spatially interpolation of public climatic data published by Instituto de Meteorologia 1951-80 combined with INETI owned data and other freely available data sources. INETI has granted DOE permission to distribute versions of the individual INETI files in converted format suitable for EnergyPlus (EPW) and make those files available to users at no cost via this EnergyPlus web site.
The INETI synthetic data are © 2005 Instituto Nacional de Engenharia, Tecnologia e Inovação, Lisboa, Portugal. http://www.ineti.pt
ISHRAE India Weather Data Files (ISHRAE)[LINK]
Developed for use in simulating building heating and air conditioning loads and energy use, and for calculating renewable energy utilization, this set of 58 weather files was developed by the Indian Society of Heating, Refrigerating, and Air-Conditioning Engineers (ISHRAE). The source data are Copyright 2005 ISHRAE. ISHRAE has made these data available to DOE under license for use at no cost to the EnergyPlus user community.
City University of Hong Kong (CUHK) Data Set[LINK]
CityUHK-45007 – WMO#450070 Typical year file Hong Kong originally in IWEC format spreadsheet jointly developed by Dr TT Chow and ALS Chan of the City University of Hong Kong supported by a CERG grant from the Research Grants Council of the Hong Kong Special Administrative Region of China. Solar radiation measured from observatory station at 22.32N 114.17’E 65m above mean sea level.
Chinese Standard Weather Data (CSWD)[LINK]
Developed for use in simulating building heating and air conditioning loads and energy use, and for calculating renewable energy utilization, this set of 270 typical hourly data weather files. These data were developed by Dr. Jiang Yi, Department of Building Science and Technology at Tsinghua University and China Meteorological Bureau. The source data include annual design data, typical year data, and extreme years for maximum enthalpy, and maximum and minimum temperature and solar radiation.
China Meteorological Bureau, Climate Information Center, Climate Data Office and Tsinghua University, Department of Building Science and Technology. 2005. China Standard Weather Data for Analyzing Building Thermal Conditions, April 2005. Beijing: China Building Industry Publishing House, ISBN 7-112-07273-3 (13228). http://www.china-building.com.cn.
Kuwait Weather Data from Kuwait Institute for Scientific Research (KISR)[LINK]
Two weather files for Kuwait based on measured meteorological data for Kuwait International Airport and KISR’s coastal weather station. Provided by KISR in spreadsheet format.
Egyptian Weather for Energy Calculations (EWEC)[LINK]
Developed for standards development and energy simulation by Joe Huang from data provided by National Climatic Data Center for periods of record from 12 to 21 years, all ending in 2003. Joe Huang and Associates, Moraga, California, USA.
Israel weather data (MSI)[LINK]
Weather data for Israel locations developed by Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, Israel, from data provided by the Israel Meteorological Service.
Representative Meteorological Year (RMY) Australia Climatic Data[LINK]
RMY Australia Representative Meteorological Year Climate Files Developed for the Australia Greenhouse Office for use in complying with Building Code of Australia. These data are licensed through ACADS BSG Ltd for use by EnergyPlus users. For use in any other formats, users must contact ACADS BSG Ltd for licensing information.
The RMY data are © 2006 Commonwealth of Australia, Department of the Environment and Water Resources, Australia Greenhouse Office, Canberra, ACT, Australia. www.greenhouse.gov.au/buildings/code.html (URL has since been removed, so replaced with a link on The Internet Archive from 2007.) All intellectual property rights reserved.
Iranian Typical Meteorological Year (ITMY)[LINK]
Typical year weather files have been created for Tehran from weather data for 1992 through 2003 published by the Islamic Republic of Iran Meteorological Organization (IRIMO) for Tehran Mehrabad. Developed for standards development and energy simulation by Joe Huang, White Box Technologies.
New Zealand National Institute of Water & Atmospheric Research Ltd (NIWA)[LINK]
The New Zealand Energy Efficiency and Conservation Authority (EECA) has developed a Home Energy Rating Scheme (HERS) for New Zealand households based on software simulation of energy loss and demand. The software requires hourly data to represent the different climates zones around New Zealand, especially for larger population centres. These climate data consist of hourly records for an artificial year created from twelve representative months.
Liley, J Ben, Hisako Shiona, James Sturman, David S Wratt. 2007. Typical Meteorological Years for the New Zealand Home Energy Rating Scheme. Prepared for the Energy Efficiency and Conservation Authority. NIWA Client Report: LAU2007- 02-JBL. NIWA, Omakau, New Zealand.
Chartered Institution of Building Services Engineers (CIBSE)[LINK]
The CIBSE, in association with the (UK) Met Office has produced ‘Test Reference Years’ and ‘Design Summer Years’ for 14 UK locations for use with building energy simulation software. The data sets are available in various formats, including EnergyPlus/ESP-r. These data are NOT available on the EnergyPlus web site. For further details, see:
www.cibse.org/index.cfm?go = publications.view&PubID = 332&S1 = y&L1 = 0&L2 = 0
Meteonorm Data[LINK]
Meteonorm software can be used when there is no measured data near the location for the simulation. Meteonorm extrapolates hourly data from statistical data for a location. Where statistical data aren’t available, Meteonorm interpolates from other nearby sites. Generally a statistical approach is a last resort – weather files generated from statistics will not demonstrate the normal hour-to-hour and day-to-day variability seen in measured data. Meteonorm version 6 will directly write EPW files.
Other Formats[LINK]
The data sets and formats described above are some of the newest formats available for use with building simulation programs. Source data comes in various formats. Typically the files are ASCII, but the data items, units, item location, and record length vary from format to format. NCDC can provide historical data in a variety of formats: TD-3280, TD-3510, TD-9950 (DATSAV2), TD-9956 (DATSAV3) and TD-1440 (CD144). The EnergyPlus weather processor cannot process any of the types directly.
Source
—————– —— ——– —————– ——– —— ————— ——————- ——– ——-
ETMY 11 11 IGDG 66 66 IMGW 61 61 INETI 2 2 ISHRAE 58 58 ITMY 1 1 IWEC 5 12 49 19 20 122 227 KISR 2 2 Los Alamos TMY2 1 1 MSI 4 4 NIWA 16 16 RMY 80 80 SWEC 2 50 52 SWERA 37 33 66 20 156 TMY 229 1 4 234 TMY2 235 1 1 237 TMY3 1011 7 2 1020 Totals 1476 0 51 58 176 39 123 305
: Summary of Downloadable Weather Data by Type
One other format worth mentioning is TRY. TRY is “test reference year” data that did not include solar radiation data. “Test Reference Year” is a term that usually denotes selection of a specific year of “real” data based on some statistical procedure. The original TRY data (TD-9706) was based on an ASHRAE procedure to select the data from a “period of record”. “The principle of the selection is to eliminate years in the period of record containing months with extremely high or low mean temperatures until only one year remains.” The weather conversion utility cannot process data in “TRY” format. However, many organizations develop data for reference year data (e.g. European TRY, Moisture Reference Data).
Custom Format[LINK]
Using a “definitions” file (see Description of “Def” input file), the weather converter can process a wide range of data formats. In the table above, both the GDG and CTYW weather data was processed by a custom format approach.
Solar Data[LINK]
Source weather data files may or may not contain solar data. All of the files that can be processed by the EnergyPlus Weather conversion utility contain solar data. The weather processor will transfer this data to the EPW weather file and the EnergyPlus simulation program will use it.
Historical weather data files in CD144 format do not contain solar data nor is such data generally available for a specific location and time period. In this case, ersatz solar data must be generated from cloud cover and other data using sky models and regression formulas. Currently, neither the Weather Conversion utility nor the EnergyPlus program synthesizes this data. However, the weather conversion utility can use any two of the commonly recorded data (i.e. two of Global Horizontal Radiation, Horizontal Diffuse Radiation and Direct Normal (or Direct Horizontal) Radiation to calculate the EnergyPlus primary solar data of Direct Normal and Horizontal Diffuse Radiation values).
Documentation content copyright © 1996-2026 The Board of Trustees of the University of Illinois and the Regents of the University of California through the Ernest Orlando Lawrence Berkeley National Laboratory. All rights reserved. EnergyPlus is a trademark of the US Department of Energy.
This documentation is made available under the EnergyPlus Open Source License v1.0.