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Here at MEA we often get asked questions that are deceptively straight forward. Questions that upon first glance seem easy to answer. One such question is about how much solar is installed in Maryland. The answer to this requires a bit of a calculus. The policy and analysis work my team does at MEA, requires us to strike a balance between the need for a quick (and sometimes immediate) answer and ensuring that the answer is not undermined by the inherent biases in the data. So, I thought this might be a great way to introduce myself as a MEA Blog writer.

We get asked about solar pretty regularly, and when asked, we have two sources of information. The first is the internal database that MEA uses to track our residential and commercial solar grants. The second is the PJM-GATS database that is used to track all systems registered for our solar Renewable Portfolio Standard program. In the early years of the RPS (i.e. before 2009), there were only a handful of solar installations in the state and our database had the best information because the majority of people applied for MEA grants. After the solar RPS “carve out” was passed in 2008, it is now a safe assumption that the vast majority of solar systems are registered in GATS, the Generation Attribute Tracking System used by states in PJM for RPS compliance.

When I checked GATs on July 30, 2014, there were 186.308 MW of solar systems registered in the database. Seriously! Based on this information, I can say with total confidence that at least 186.308 MW of solar is registered in Maryland right now. When we need to have a quick update, we will use this figure as it is accurate, available, and citable. However, based on how GATs works this figure likely understates the actual progress of the industry because it doesn’t capture every project.