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Solar Data Hub

Kirsten Orwig

NREL Transmission 

and Grid Integration 

Group

UWIG Solar User 

Group Meeting

April 13, 2011

PIX 17749 NREL/PR-5500-51372

PIX 16995

PIX 15558
National Renewable Energy Laboratory Innovation for Our Energy Future

1min

What is the Need?

• FEAR and UNCERTAINTY among utilities about high 

penetrations of PV −

• Concerns: system stability, increases in reserves, CPS2 

violations, voltage regulation, etc.

• Concerns must be addressed

to reach high penetrations.

• Primary barrier?

DATA!

Source: Tom Hansen, Tucson Electric Power

THIS TERRIFIES UTILITIES
National Renewable Energy Laboratory Innovation for Our Energy Future

Why?

• Demand for solar is increasing rapidly.

• Unknowns:

• Impacts of variability on the grid;

• Full extent of geographic diversity benefits;

• Correlation and interaction between PV and other renewable energy 

resources;

• Correlation of ramps in power production to ramps in irradiance.

• Benefits:

• Predicted data for integration studies, transmission planning, and other 

studies;

• Power production forecasts for utility operations;

• Model and forecast validation;

• Better knowledge, better management.

• High-resolution solar radiation and power production data are 

not readily available from large plants.

• Data collection and analysis done on an ad-hoc basis – a more 

sophisticated approach needed.
National Renewable Energy Laboratory Innovation for Our Energy Future

What We Know

For wind: 

• The variability decreases with increasing geographic diversity within plants 

and across regions.

• Plant production does not scale linearly with capacity.

• Variability operational impacts tend to be on load following, and not on a 

regulation time frame.

• Load forecast errors are not linearly related to wind forecast errors.

• Studies suggest storage is unnecessary with penetration levels up to 30%.

For solar:

• Plant production does not scale linearly with capacity.

• Ramps can occur at shorter time scales than wind. 

• Adjacent PV plants are more correlated than adjacent wind plants, but 

correlation decreases with distance.

• Solar power plants may contribute to voltage and frequency regulation 

within a region.

• More solar data is needed to develop accurate models of large-scale 

solar plant performance and characterize solar variability.
National Renewable Energy Laboratory Innovation for Our Energy Future

Solar Data Hub

• Born from PV Variability Working Group.

• Project Team consists of DOE labs, EPRI, and industry partners.

• Development sponsored by DOE.

• Centralized data repository:

• Collect, manage, store, and provide access;

• Public and proprietary information will be stored in the data hub;

• Proprietary information will be secure and have restricted access;

• Data quality will be evaluated through a semi-automated QA/QC 

process.
National Renewable Energy Laboratory Innovation for Our Energy Future

Beta Version ─ Went Live April 1

http://solardatahub.org
National Renewable Energy Laboratory Innovation for Our Energy Future

Future Version
National Renewable Energy Laboratory Innovation for Our Energy Future

Timeline for Upgrades (TENTATIVE)

Objective Timeline

Add Feedback form May 1, 2011

Semi-automated quality control of data June 30, 2011

Basic visualization (time series plots) August 30, 2011

Provide real-time data feed capability November 30, 2011

Enhanced visualization and coordination 

with PVDAQ

January 31, 2012

Incorporate grid integration datasets June 30, 2012