Solar resource for high penetration and large scale applications

As the penetration of PV increases, improved accuracy and finer spatial and temporal resolution of solar data sets are needed to optimize the performance of these technologies in the energy system of a particular region or country.

International collaboration and consensus on developing and managing these data sets will expedite the high penetration of solar technologies, and improve markets for these technologies. Large scale PV plants now need accurate resource and forecast data due to high investment costs. Therefore Task participants will focus on the following two scientific issues:

High frequency variability and solar forecasts for managing grids with high penetration of PV and local storage

High quality solar resource assessments and forecasts for solar installations notably in the multi MW class

High frequency variability and high quality needs are also important issues for the planning and the operation of Concentrating Solar Thermal facilities and CPV, which will be a focus of the Task as well. In addition, the development of bankable data sets for system sizing and accurate continuous data sets for performance evaluation are important to Solar Heating and Cooling technologies, and will also be a focus of this task.

Goals

The main goals of Task 16 are to lower barriers and costs of grid integration of PV and lowering planning and investment costs for PV by enhancing the quality of the forecasts and the resources assessments. To reach this main goal the Task has the following objectives:

Lowering uncertainty of satellite retrievals and Numerical Weather Prediction (NWP) models for solar resource assessments and nowcasting.

Define best practices for data fusion of ground, satellite and NWP data (re-analysis) to produce improved datasets, e.g. time series or Typical Meteorological Year (TMY).

Develop enhanced analysis of long-term inter-annual variability and trends in the solar resource.

Develop and compare methods for

-            Estimating the spectral and angular distributions of solar radiation (clear and all-sky conditions)

-            Describing the spatial and temporal variabilities of the solar resource

-            Modelling point to area forecasts

-            Probabilistic and variability forecasting

Contribute to or setup international benchmark for data sets and for forecast evaluation.

As the scope of Task 16 is also directly linked to Concentrating Solar Power and solar thermal installations the collaboration with the two TCPs dealing with these topics is of great importance. IEA PVPS Task 16 will be a joint task with IEA SolarPACES and will keep minimal collaboration with IEA SHC.

Approach

The work programme of the proposed Task 16 addresses on one side scientific meteorological and climatological issues to high penetration and large scale PV in electricity networks, but also includes a strong focus on user needs and for the first time a special dissemination subtask. Dissemination and user interaction is foreseen in many different ways from workshops and webinars to paper and reports.

The project requires the involvement of key players in solar resource assessment and forecasting at the scientific level (universities and research institutions) and commercial level (companies). A consortium of 55 institutions of 20 countries has been formed. This includes large science centres like DLR, NREL or Fraunhofer, universities like State Univ. of New York, Mines ParisTech or Univ. of Jaen, national weather services like DWD, BOM or DMI and data providers like Solargis, Vaisala or Meteotest.

The work plan is also focused on work that can only be done by international collaboration like definition and organization of benchmarks, definition of common uncertainty and variability measures.  E.g. the measure P10/90 years, which is often used today, lacks a commonly accepted definition up to now.

Subtasks

The work programme is organized into three main technical subtasks (subtasks 1 – 3) and one dissemination subtask (subtask 4), including three to four activities:

Subtask 1: Evaluation of current and emerging resource assessment methodologies:

Ground based methods
Numerical weather models (NWP)
Satellite-based methods
Benchmarking framework

 

Subtask 2: Enhanced data & bankable products:

Data quality & format
Merging of satellite, NWP and ground data
Spatio-temporal high variability
Long-term inter-annual variability
Products for the end-users

 

Subtask 3: Evaluation of current and emerging solar forecasting techniques:

Value of solar power forecasts
Regional solar power forecasting
Variability forecasting and probabilistic forecasting

 

Subtask 4: Dissemination and Outreach:

Develop a Task Brochure
Create a 6-month Task Newsletter
Conduct periodic (annual) Subtask-level webinars and/or conference presentations
Update of the solar resource handbook

 

Publications

The Task 16 starts in July 2017 and will go on for three years. Therefore no publications are yet available. The main contribution of the preceding Task IEA SHC 46 was the solar resource handbook (LINK), which is currently updated.