DuraMAT	Capability	1:	
Data	Analytics	
Anubhav	Jain	
Lawrence	Berkeley	National	Laboratory	
August	28,	2018
Goals	of	the	data	analytics	thrust	
Field deployment
Data Hub Data analytics
Materials
Forensics &
Characterization
Predictive
simulationModule testing
Techno-economic
analysis
Data analytics is a cross-
cutting thrust that works with
DuraMat partners to provide
software, visualization, and
data mining capabilities.
This thrust does not produce
data itself!
Project	1:	Clear	Sky	Detection	(background)	
Jordan, D. C., Deline, C., Kurtz, S. R.,
Kimball, G. M. & Anderson, M. Robust
PV Degradation Methodology and
Application. IEEE J. Photovoltaics 8,
525–531 (2018).
In many analyses, data filtering /
preprocessing greatly affects final
results!
D. Jordan et al. showed that clear
sky filtering produces degradation
rates closer to expectation and
20% different than without filtering!
Generally clear
Scattered cloudsPersistent clouds
Can we design an algorithm that automatically and
reliably distinguishes clear sky periods based on GHI
measurements – across locations and data frequencies?
Approach: use satellite data to modify a published clear
sky detection technique (Reno and Hansen, 2016) to
generalize across locations and data frequencies.
Project	1:	Clear	Sky	Detection	(results)	
Using satellite clear sky labels as a guide,
we can design an “optimized” clear sky
detection algorithm with no parameters
that works better than existing pvlib
across sites and data frequencies!
Heatmaps	
plot	F0.5	
scores,	or	
classification	
accuracy,	of	
clear	sky	
algorithms	
Visual inspection confirms that clear sky
classifications from the optimized
algorithm are more relevant and correct.
Next: integration into pvlib and/or rdtools
default	
optimized	
Sample	GHI	
data	and	clear	
sky	
classifications	
for	BMS	site,	
30	minute	data	
frequency
Project	2:	Degradation	dashboards	(background)	
Backend tools like rdtools (NREL, kWh Analytics) expose many powerful functions for
processing and analyzing data through programmatic (e.g., Python, MATLAB) APIs.
How can we make some of these tools more visual, interactive, and exploratory?
Jordan, D. C., Deline, C., Kurtz, S. R.,
Kimball, G. M. & Anderson, M. Robust
PV Degradation Methodology and
Application. IEEE J. Photovoltaics 8,
525–531 (2018).
www.github.com/NREL/rdtools
Project	2:	Degradation	dashboards	(results)	
We have built interactive dashboards that
analyze data from PVOutput.org
Goal: make the backend tools interactive!
Misc.	-	contact	angle	analysis,	I-V	curve	analysis	
Automated contact angle
analysis for evaluating anti-
soiling coatings
E x t r a c t i o n o f I - V c u r v e
parameters, detection of
m i s m a t c h , a n d l e a r n i n g
“features” of I-V curves
Future	directions	
•  Relating	combined	accelerating	stress	testing	(C-AST)	
and	field	measurements	
•  Working	with	other	data	analytics	efforts	in	the	field	
(e.g.,	Case	Western)	
•  Open	to	other	project	ideas!	
–  contact:	ajain@lbl.gov	
•  Collaborators:	Benjamin	Ellis,	Mike	Deceglie,	Birk	Jones,	
Josh	Stein,	Dirk	Jordan,	Laura	Schelhas,	Stephanie	
Moffitt,	Margaret	Gordon

DuraMat Data Analytics