Products
menu item
Prospect
Quick estimate of PV site's solar potential
menu item
Evaluate
Time Series & TMY data for energy modelling
menu item
Monitor
Real-time PV output assessment
menu item
Forecast
Solar power output forecast for up to 14 days
menu item
Analyst
Simplified & unified solar data management
menu item
Integrations
Automate delivery of Solargis data
Use cases
menu item
Site selection
Find the right solar project location
menu item
Energy yield simulation
Analyze potential gains and risks
menu item
Optimizing power plant design
Find optimum power plant design
menu item
Real power plant performance
Discover the true output
menu item
Power output forecast
Predict solar project energy output
menu item
Ground data verification
Verify quality of solar & meteo measurements
Solar Resource & Meteo Assessment
Detailed solar resource validation and assessment
Site Adaptation of Solargis Models
Combining satellite data with on-site measurements
Quality Control of Solar & Meteo Measurements
Correction of errors in ground-measured data
Customized GIS Data
Customized Solargis GIS data for your applications
PV Energy Yield Assessment
Estimated energy uncertainties and related data inputs
PV Performance Assessment
Energy estimate for refinancing or asset acquisition
PV Variability & Storage Optimization Study
Understand output variability across wide geo regions
Regional Solar Energy Potential Study
Identification of locations for solar power plants
Our expertise
How our technology works
Methodology
How we transform science into technology
API & integration
How to integrate Solargis data via API
Product guides & documentation
Release notes
Success stories
Blog
Ebooks & Whitepapers
Webinars
Publications
Events
Free Maps & GIS Data
Solar performance maps
About Solargis
Partners
ISO Certification
Careers

What is the difference between multi-year time series and TMY data?

The Full Time Series is the original data product generated by Solargis model, the one which contains the data values for the whole registered period. Since the information contained by a Time Series file is not compressed, it is the most versatile file able to provide inputs for all the calculations needed to run a complete solar resource assessment.

Solargis multi-year time series is most typically used for the following purposes:

  • To understand seasonal and inter-annual variability of solar resource
  • To understand occurrence of extreme irradiance and temperature events - for design optimization of solar power systems
  • Input data for energy simulation of solar power systems
  • For accuracy enhancement of long-term satellite-derived irradiance estimates - when high-quality irradiation measurements are available at project site

The Typical Meteorological Year (TMY) is a popular data product designed for summarizing the average weather conditions of a specific site in a period of a single year. TMY data is primarily used for energy simulation purposes, as popular simulation software such as PVsyst, SAM, etc. typically work with 8760 hourly values representing a typical year. The main reason for the popularity of TMY dataset for solar energy simulation is compatibility of such data with popular energy simulation software and speed of simulation.

The TMY is indeed constructed from Time Series (more info here), so it is usual to find both data files within the same order files in Solargis. However, since TMY data results in an avoidable loss of information, it is recommended to use a full time series file when possible.

To download sample Time Series or TMY you can click here.

Data description

Time Series

TMY

Period

Data from the full period available since 1994/1999/2007 (depending on the region)

Data from a summary year constructed by concatenation of data from typical months

Data values

Up to 876,000 approx.

8,760

Data time step

15-minute / Hourly

Hourly

Spatial resolution

250 meters

250 meters

 

Applications

Time Series

TMY

Running energy simulations 

Yes

Yes

Calculation of absolute max / min values

Yes

No

Calculation of interannual variability

Yes

No

Comparison of data sources

Yes

No

Adjustment of values using ground data

Yes

No

Why are meteo data for selected months in TMY file different from meteo data for corresponding months in time series dataset?

When generating TMY data, we try to select months in such a way that annual sum of GHI/DNI values in the TMY file is consistent with the annual average calculated from time series. However, it may not be possible to find representative months where the sum of irradiation as well as meteo values will equal the long-term average. Therefore, we may be required to slightly adjust the meteo values to maintain similar averages as calculated from time series.

More information on how Solargis TMY data is prepared can be seen here.