solar and wind power forecasting
TRANSCRIPT
Jan Schmelter
Euro Arab Training Course:
SMART GRID AND INTEGRATION OF RENEWABLE ENERGY
Granada, Spain
28th April 2016
>>>Solar and wind power forecasting
>>>Company profile
Integration of renewables into grids and markets Service provider for energy meteorology since 2004 Areas of business
– Wind and solar power predictions worldwide
– Predictions for grid operators and traders
– Software for Virtual power plants and demand side management
– Development
• Industry projects
• National and international research projects
70 people
>>>Choice of international customers
PJM Interconnection
BPABonneville Power Administration
Tennessee Valley Authority
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
How does a power prediction work?
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
How does a power prediction work?
Why is a power prediction difficult?
>>>Central Questions
Why are power predictions necessary? Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
How does a power prediction work?
Why is a power prediction difficult?
>>>lo
ad
[% m
ax.
load
]
time [d] 0
0
100
1 2 3 4 5 6 7
Grid load without wind power
Why are power predictions necessary?
wind and solar power depends on meteorological conditions
>>>lo
ad
[% m
ax.
load
]
time [d] 0
0
100
1 2 3 4 5 6 7
Residual load due to renewable production
Grid load without wind power
Why are power predictions necessary?
wind and solar power depends on meteorological conditions
>>>lo
ad
[% m
ax.
load
]
time [d] 0
0
100
1 2 3 4 5 6 7
Residual load due to renewable production
Grid load without wind power
Why are power predictions necessary?
wind and solar power depends on meteorological conditions
contribution of wind and solar must be known in advance
power forecasts provide schedule of expected generation
>>>How does a wind power prediction look like?
Schedule containing 24 or 96 values per day
Single plants or aggregate
Optional confidence bands
>>>How does a solar power prediction look like?
Schedule containing 24 or 96 values per day
Single plants or aggregate
Optional confidence bands
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power
predictions? What are the recommendations to implement forecasts?
How does a power prediction work?
Why is a power prediction difficult?
>>>Who needs wind and solar power forecasts?
grid operators (TSOs, DSOs)– balancing– dispatch / re-dispatch– load flow calculations– congestion management
>>>Who needs wind and solar power forecasts?
grid operators (TSOs, DSOs)– balancing– dispatch / re-dispatch– load flow calculations– congestion management
energy traders– trading wind and solar power on energy markets– influence of renewable energy on spot market price
>>>Who needs wind and solar power forecasts?
grid operators (TSOs, DSOs)– balancing– dispatch / re-dispatch– load flow calculations– congestion management
energy traders– trading wind and solar power on energy markets– influence of renewable energy on spot market price
wind farm / solar plant operators– schedule maintenance– send schedule to grid operator
>>>Who needs wind and solar power forecasts?
Time scale of forecast Stakeholder Area of application
Shortest-term(0 – 6 h)
Traders Trading on intraday energy marketControl of curtailment due to negative market price
Grid operatorsload dispatch centerssystem operators
Balancing Unit re-dispatchCurtailment of power plants
Speculators Influence of renewable production on market price
Short-term(6 – 48 h)
Traders Trading on day-ahead energy marketParticipation in regulation marketInfluence of reneables on market price
Grid operatorsload dispatch centerssystem operators
Unit dispatchLoad flow calculationsDA congestion forecast
Plant operators Day-ahead planning of maintenance
Medium-term(2 – 10 days)
Traders Trading on long-term markets
Grid operatorsload dispatch centerssystem operators
2DA congestions forecastWeek-ahead planning
Plant operators Medium-term planning of maintenance
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement
forecasts? How does a power prediction work?
Why is a power prediction difficult?
>>>National register of wind and solar plants
Register should contain following standing data of new installations for every unit:
unique identifier for each unit technology of the generator (i.e. wind, pv, csp) installed capacity of each generator geographical location of each generator according to the World
Geodetic System 1984 as a degree in decimals associated grid connection point for wind turbines: hub height and rotor diameter for PV modules: inclination angle and orientation date of initial operation and date of decommissioning if the generated power is used on location or only fed in to the grid
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
~ 20
directmarketers
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
~ 20
directmarketers
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
~ 20
directmarketers DSOs
~ 880
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
~ 20
directmarketers DSOs
~ 880
>>>
~ 20
directmarketers
The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
~ 880
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
Wind farmowners
~ 20.000
~ 880~ 20
directmarketers
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
Wind farmowners
~ 20.000
~ 880~ 20
directmarketers
Solar plantowners
~ 3.000.000
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
Wind farmowners
~ 20.000
~ 880~ 20
directmarketers
Solar plantowners
~ 3.000.000
some othercompanies
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
Wind farmowners
~ 20.000
~ 880~ 20
directmarketers
Solar plantowners
~ 3.000.000
some othercompanies
>>>The plant register for renewables in Germany
Forecaster
plant register
Federal NetworkAgency
TSO No 4
TSO No 3
TSO No 2
TSO No 1
DSOs
Wind farmowners
~ 20.000
~ 880~ 20
directmarketers
Solar plantowners
~ 3.000.000
some othercompanies
TRANSPARENCY?
>>>The plant register for renewables: the transparent way
Forecaster
plant register
Federal NetworkAgency / TSO
Wind farmowners
Solar plantowners
>>>Grid code requirements
The grid code should contain the following data for every unit:
power output (real power output) available active power (power output due to meteorological conditions) Information on scheduled availability of wind farms and solar plants in
terms of effective installed power to cover e.g. scheduled maintenance, known outages of machines
Information on current availability of units Information on scheduled curtailment, i.e. limits to power output Information on currently activated curtailment by grid operators or
dispatch centres Meteorological data that measure the available resource
Wind farms: wind speed and direction close to hub height Solar plants: solar irradiation (direct and diffuse separately if possible)
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
How does a power prediction work? Why is a power prediction difficult?
>>>
Goal is power conversion:
transfer meteorological variables into power output of wind or solar plants
Basic approaches to wind and solar power prediction
>>>
Goal is power conversion:
transfer meteorological variables into power output of wind or solar plants
state of the art: use of numerical weather prediction models (NWP)
Basic approaches to wind and solar power prediction
>>>State of the art: prediction systems
physical model
statisticalpost processing
different NWPs
standing dataof power plants
final forecast
online data
forecaster external data
>>>… vertical interpolation is also needed
100 m
10 m
wind speed
heig
hthub height unstable
NWP datastable
NWP data
wind profile changes with atmospheric conditions
>>>Combination of weather models
Weighting factors according to capabilities in different weather situations
Weather classification
Weather data
wind powerprediction
Single wind power predictions
>>>
Forecast improvement due to intelligent model combination !
combination
measurement
solar power prediction
Benefit of combination
>>>Central Questions
Why are power predictions necessary?
Who needs wind and solar power predictions?
What are the recommendations to implement forecasts?
How does a power prediction work?
Why is a power prediction difficult?
>>>Different types of forecast errors
Large amount of different types of errors:
… errors in meteorological forecasts
>>>Different types of forecast errors
Large amount of different types of errors:
… errors in meteorological forecasts
… errors in power transformation
>>>Different types of forecast errors
Large amount of different types of errors:
… errors in meteorological forecasts
… errors in power transformation
… unknown status of power plants
>>>„Artificial“ forecasting errors due to unknown plant status
Wind farm availability below 100 %
Wind farm shut down due to grid congestion
>>>To be considered: curtailment and scheduled outages
Prediction using curtailment information(wind farm limited to 80 MW)
Prediction assuming full availability of wind farm (200 MW installed capacity)
Time schedules for planned outages or curtailments can be transmitted to Previento to be considered in the forecasts.
>>>Different types of forecast errors
Large amount of different types of errors:
… errors in meteorological forecasts
… errors in power transformation
… unknown status of power plants
… difficult meteorological situations
>>>… some more literature
Variable Renewable Energy Forecasting - Integration into Electricity Grids and Makets - A Best Practice Guide
Release: Original publication July 2015