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Targeting High-Value Solar Installations to Reduce Costs to the Electric Grid
Last registered on May 17, 2019


Trial Information
General Information
Targeting High-Value Solar Installations to Reduce Costs to the Electric Grid
Initial registration date
October 03, 2018
Last updated
May 17, 2019 1:42 PM EDT
Primary Investigator
Yale University
Other Primary Investigator(s)
PI Affiliation
yale University
Additional Trial Information
In development
Start date
End date
Secondary IDs
In 2017, the installed capacity of distributed solar photovoltaics (PV) reached more than 16 gigawatts in the United States. Solar PV has seen increasing investment over the last several years due to improvements in technology and steady declines in prices. However, there is little consensus on what impact residential solar deployment will have on electricity grid systems. While solar advocates tout the many benefits of increased distributed solar PV development, many electric utilities have cited concerns over how new, intermittent, distributed resources will be incorporated into existing grid infrastructure and planning.
This study targets adoption of solar installations in areas with the highest potential value to the electric grid. We analyze the costs and benefits of these high-value solar installations to the electricity network, by measuring their effect on a number of network metrics.

External Link(s)
Registration Citation
Gillingham, Kenneth and Marten Ovaere. 2019. "Targeting High-Value Solar Installations to Reduce Costs to the Electric Grid." AEA RCT Registry. May 17. https://doi.org/10.1257/rct.3363-2.0.
Former Citation
Gillingham, Kenneth, Marten Ovaere and Marten Ovaere. 2019. "Targeting High-Value Solar Installations to Reduce Costs to the Electric Grid." AEA RCT Registry. May 17. http://www.socialscienceregistry.org/trials/3363/history/46692.
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Experimental Details
In each targeted subcircuit we are running a behavioral intervention designed to encourage solar adoption. This intervention involves a roughly 18-week campaign, a single chosen solar installation company (based on a competitive bidding process), discount pricing, a kick-off event, targeted communication, etc.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Highly increased penetration of distributed solar PV generation in small local subcircuits (500-2000 customers).
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Measuring the effect of increased PV penetration on a number of network metrics like line loading, voltage, losses, outages and transformer loading.
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
A set of subcircuits are matched to a number of utility-identified high-value subcircuits. The utility-identified subcircuits receive a utility-managed campaign, while the matched subcircuits are randomly assigned to a "Solarize" campaign and a control group. Both campaigns start at approximately the same time.

Partner utilities collect data on all residential solar installations in their coverage area as well as the network metrics.
Experimental Design Details
Randomization Method
Randomization done in office by a computer
Randomization Unit
Randomization is at the electric subcircuit level, after initial matching
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
20 subcircuits
Sample size: planned number of observations
20+ subcircuits
Sample size (or number of clusters) by treatment arms
2 subcircuits receive solar campaign + rate rider
4 subcircuits receive solar campaign (likely additional campaigns + controls depending on funding)
6 municipalities are in the control

+ Estimate for the ones in Eversource area?
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
Yale Institutional Review Board
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Is data collection complete?
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)