Timestamps

Overview¶

Supported by Pandas
- Arbitrary time series supported by Pandas' DatetimeIndex
- Relevant input parameters : start_time, end_time, periods and frequency.
Note

Learn more about frequency strings at Offset aliases.
IANA Time Zone Database
- Support for valid time zone identifiers from the IANA Time Zone Database
Defaults
Attention!
- If not given, default time is 00:00:00. No solar irradiance at this time !
- UTC is the default timezone in which internal calculations are performed anyway.
- Frequency of timestamps is unrelated to the groupby option !
Working examples
Example
- Examples that should just work

PVGIS relies on the excellent timestamping engine of Pandas.

We can use all of the flexibility to build almost any kind of series of timestamps!

Optional parameters¶

The basic entrypoint for timestamp/s is the positional argument timestamps. Notwithstanding, a series of optional input parameters offer the flexibility to generate custom series of timestamps. These are :

--start-time : a starting timestamp
--end-time : an ending timestamp
--periods : the number of timestamps within a time range starting with the start_time and ending with the end_time timestamp.
--frequency :

Source code of...

Update-Me

Examples¶

Local time and zone¶

Interested for the photovoltaic power output at your current local time and zone ? Just ommit the timestamp altogether !

pvgis-prototype power broadband 8 45 214 -v

        Power series [W]         

  Time                  Power ⌁  
 ─────────────────────────────── 
  2025-12-01 22:14:32   0.0      

  ⅀ / μ                 0.0      

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 3.142, Surface Tilt ⦥: 0.785   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

Using the system's current time and zone!

The above example expectedly picked up the time and zone of the virtual computer on which this very page has been build after some change commited in the source code tree!

Missing positional parameters?

Remember, a specific user-defined timestamp, or list of timestamps separated by comma for the matter, would fail due to absence of all required positional arguments, i.e. :

Usage: pvgis-prototype power broadband [OPTIONS] LONGITUDE LATITUDE ELEVATION
                                       [SURFACE_ORIENTATION] [SURFACE_TILT]
                                       [TIMESTAMPS]
Try 'pvgis-prototype power broadband --help' for help.
╭─ Error ──────────────────────────────────────────────────────────────────────────────────────╮
│ Invalid value for '[SURFACE_ORIENTATION]': '2010-01-27 12:00:00' is not a valid float range. │
╰──────────────────────────────────────────────────────────────────────────────────────────────╯

Start and end dates¶

pvgis-prototype power broadband \
8 45 214 180 45 \
--start-time '2010-01-27' \
--end-time '2010-01-28'

0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,345.069,550.152,684.83,755.155,765.285,715.892,603.901,423.714,163.78,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0

Start and end date-times¶

pvgis-prototype power broadband \
8 45 214 180 45 \
--start-time '2010-01-27 06:00:00' \
--end-time '2010-01-28 17:30:00' \
-v

         Power series [W]          

  Time                  Power ⌁    
 ───────────────────────────────── 
  2010-01-27 06:00:00   0.0        
  2010-01-27 07:00:00   0.0        
  2010-01-27 08:00:00   345.069    
  2010-01-27 09:00:00   550.152    
  2010-01-27 10:00:00   684.83     
  2010-01-27 11:00:00   755.155    
  2010-01-27 12:00:00   765.285    
  2010-01-27 13:00:00   715.892    
  2010-01-27 14:00:00   603.901    
  2010-01-27 15:00:00   423.714    
  2010-01-27 16:00:00   163.78     
  2010-01-27 17:00:00   0.0        
  2010-01-27 18:00:00   0.0        
  2010-01-27 19:00:00   0.0        
  2010-01-27 20:00:00   0.0        
  2010-01-27 21:00:00   0.0        
  2010-01-27 22:00:00   0.0        
  2010-01-27 23:00:00   0.0        
  2010-01-28 00:00:00   0.0        
  2010-01-28 01:00:00   0.0        
  2010-01-28 02:00:00   0.0        
  2010-01-28 03:00:00   0.0        
  2010-01-28 04:00:00   0.0        
  2010-01-28 05:00:00   0.0        
  2010-01-28 06:00:00   0.0        
  2010-01-28 07:00:00   0.0        
  2010-01-28 08:00:00   347.351    
  2010-01-28 09:00:00   552.1      
  2010-01-28 10:00:00   686.761    
  2010-01-28 11:00:00   757.198    
  2010-01-28 12:00:00   767.531    
  2010-01-28 13:00:00   718.446    
  2010-01-28 14:00:00   606.904    
  2010-01-28 15:00:00   427.433    
  2010-01-28 16:00:00   168.852    
  2010-01-28 17:00:00   0.0        

  ⅀ / μ                 10040.353  

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 3.142, Surface Tilt ⦥: 0.785   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

Frequency¶

pvgis-prototype power broadband \
8 45 214 180 45 \
--start-time '2010-01-27 06:00:00' \
--end-time '2010-01-28 17:30:00' \
--frequency 30min \
-v

         Power series [W]          

  Time                  Power ⌁    
 ───────────────────────────────── 
  2010-01-27 06:00:00   0.0        
  2010-01-27 06:30:00   0.0        
  2010-01-27 07:00:00   0.0        
  2010-01-27 07:30:00   208.709    
  2010-01-27 08:00:00   345.069    
  2010-01-27 08:30:00   456.748    
  2010-01-27 09:00:00   550.152    
  2010-01-27 09:30:00   625.85     
  2010-01-27 10:00:00   684.83     
  2010-01-27 10:30:00   727.666    
  2010-01-27 11:00:00   755.155    
  2010-01-27 11:30:00   767.562    
  2010-01-27 12:00:00   765.285    
  2010-01-27 12:30:00   748.089    
  2010-01-27 13:00:00   715.892    
  2010-01-27 13:30:00   667.973    
  2010-01-27 14:00:00   603.901    
  2010-01-27 14:30:00   522.66     
  2010-01-27 15:00:00   423.714    
  2010-01-27 15:30:00   306.26     
  2010-01-27 16:00:00   163.78     
  2010-01-27 16:30:00   0.0        
  2010-01-27 17:00:00   0.0        
  2010-01-27 17:30:00   0.0        
  2010-01-27 18:00:00   0.0        
  2010-01-27 18:30:00   0.0        
  2010-01-27 19:00:00   0.0        
  2010-01-27 19:30:00   0.0        
  2010-01-27 20:00:00   0.0        
  2010-01-27 20:30:00   0.0        
  2010-01-27 21:00:00   0.0        
  2010-01-27 21:30:00   0.0        
  2010-01-27 22:00:00   0.0        
  2010-01-27 22:30:00   0.0        
  2010-01-27 23:00:00   0.0        
  2010-01-27 23:30:00   0.0        
  2010-01-28 00:00:00   0.0        
  2010-01-28 00:30:00   0.0        
  2010-01-28 01:00:00   0.0        
  2010-01-28 01:30:00   0.0        
  2010-01-28 02:00:00   0.0        
  2010-01-28 02:30:00   0.0        
  2010-01-28 03:00:00   0.0        
  2010-01-28 03:30:00   0.0        
  2010-01-28 04:00:00   0.0        
  2010-01-28 04:30:00   0.0        
  2010-01-28 05:00:00   0.0        
  2010-01-28 05:30:00   0.0        
  2010-01-28 06:00:00   0.0        
  2010-01-28 06:30:00   0.0        
  2010-01-28 07:00:00   0.0        
  2010-01-28 07:30:00   211.862    
  2010-01-28 08:00:00   347.351    
  2010-01-28 08:30:00   458.798    
  2010-01-28 09:00:00   552.1      
  2010-01-28 09:30:00   627.767    
  2010-01-28 10:00:00   686.761    
  2010-01-28 10:30:00   729.64     
  2010-01-28 11:00:00   757.198    
  2010-01-28 11:30:00   769.694    
  2010-01-28 12:00:00   767.531    
  2010-01-28 12:30:00   750.474    
  2010-01-28 13:00:00   718.446    
  2010-01-28 13:30:00   670.729    
  2010-01-28 14:00:00   606.904    
  2010-01-28 14:30:00   525.972    
  2010-01-28 15:00:00   427.433    
  2010-01-28 15:30:00   310.52     
  2010-01-28 16:00:00   168.852    
  2010-01-28 16:30:00   0.0        
  2010-01-28 17:00:00   0.0        
  2010-01-28 17:30:00   0.0        

  ⅀ / μ                 20127.324  

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 3.142, Surface Tilt ⦥: 0.785   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

Number of periods¶

pvgis-prototype power broadband \
8 45 214 180 45 \
--start-time '2010-01-27 06:00:00' \
--end-time '2010-01-28 17:30:00' \
--periods 8 \
-v

         Power series [W]         

  Time                  Power ⌁   
 ──────────────────────────────── 
  2010-01-27 06:00:00   0.0       
  2010-01-27 11:04:17   757.838   
  2010-01-27 16:08:34   0.0       
  2010-01-27 21:12:51   0.0       
  2010-01-28 02:17:08   0.0       
  2010-01-28 07:21:25   170.301   
  2010-01-28 12:25:42   753.825   
  2010-01-28 17:30:00   0.0       

  ⅀ / μ                 1681.965  

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 3.142, Surface Tilt ⦥: 0.785   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

With Orientation and Tilt¶

We can define the specific orientation and tilt angles for our solar surface, right after the location coordinates and the elevation :

pvgis-prototype power broadband \
8 45 214 \
167 44 \
--start-time '2010-01-27 06:00:00' \
--end-time '2010-01-28 17:30:00' \
--periods 8 \
-v

         Power series [W]         

  Time                  Power ⌁   
 ──────────────────────────────── 
  2010-01-27 06:00:00   0.0       
  2010-01-27 11:04:17   757.969   
  2010-01-27 16:08:34   0.0       
  2010-01-27 21:12:51   0.0       
  2010-01-28 02:17:08   0.0       
  2010-01-28 07:21:25   225.475   
  2010-01-28 12:25:42   719.613   
  2010-01-28 17:30:00   0.0       

  ⅀ / μ                 1703.057  

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 2.915, Surface Tilt ⦥: 0.768   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

With Orientation only¶

Or only the orientation.

pvgis-prototype power broadband \
8 45 214 \
167 \
--start-time '2010-01-27 06:00:00' \
--end-time '2010-01-28 17:30:00' \
--periods 8 \
-v

         Power series [W]         

  Time                  Power ⌁   
 ──────────────────────────────── 
  2010-01-27 06:00:00   0.0       
  2010-01-27 11:04:17   762.257   
  2010-01-27 16:08:34   0.0       
  2010-01-27 21:12:51   0.0       
  2010-01-28 02:17:08   0.0       
  2010-01-28 07:21:25   229.079   
  2010-01-28 12:25:42   723.348   
  2010-01-28 17:30:00   0.0       

  ⅀ / μ                 1714.684  

╭───────────────────────────────────────────────────────────────────────────────────────╮ ╭──────────────────────────────────────╮
│ Location  Longitude ϑ, Latitude ϕ = 0.14, 0.785, Elevation: 214.0 m                   │ │  ⌁  Power        ⦥  Tilt             │
│ Position  Surface Orientation ↻: 2.915, Surface Tilt ⦥: 0.785   Angular units radians │ │  ⏲  Timing       ⭸  Incidence        │
│ Definitions  UTC, Incidence angle: Sun-Vector-to-Surface-Plane,                       │ │  ⯐  Positioning  ⅀  N-ary Summation  │
│ Algorithms  Timing : NOAA, Positioning : NOAA, Incidence : Iqbal                      │ │  ↻  Orientation  μ  Mean             │
╰─────────────────────────────────────────────────────────────────────────── Reference ─╯ ╰───────────────────────────── Legend ─╯

Tilt only ?

It is impossible (at the moment) to re-define the tilt angle only, without preceeding it by an orientation angle.