Knowledge is Power

Multiple sources confirm that residents seeking to install solar encounter high interconnection fees, delays, and administrative hurdles. 

Between 2019 and 2024, OPC handled 102 consumer complaints about solar applications. Most complaints involved unexpected and high interconnection fees, ranging from $2,000 to $104,000. Others involved delays in the interconnection process and administrative hurdles. This data does not include cases where residents were unaware of OPC’s assistance or chose to not seek help. 

While based on a relatively small sample size of 315 District residents, the survey found that more than 15% of homeowners who installed solar reported experiencing interconnection issues. This figure may underrepresent the full scope of the problem, as some challenges are handled directly by solar installers without the homeowner’s awareness. Three case studies by Electrify DC, news reports, and several formal cases brought to the Public Service Commission of the District of Columbia (DC PSC), confirm that unexpected costs, delays, and administrative hurdles have deterred solar adoption.

Pepco’s current hosting capacity map, instead of providing detailed, real-time data at the bus or customer level, only offers static, feeder-level data, based on minimum load and thermal rating, which estimates only thermal capacity at the feeder level and lacks the precision and updates needed for effective planning by residents and developers at the secondary voltage  and sub feeder levels.  As a result, residents and installers have no way of determining whether solar installations are going to be possible without incurring additional cost.

Pepco has stated its current hosting capacity map reflects feeder-level data for both residential and commercial installations based on minimum daylight load and thermal rating calculations. Pepco concedes that these calculations are not adequate to identify individual transformers that have reached their capacity for DER installations, and that as a result, residents and developers may be unaware of significant work and associated costs that may be required to accommodate a solar installation. Pepco has stated that as a result, residents and installers should use the Hosting Capacity Map as an initial indication that installation of a DER may be accomplished without a needed system upgrade.

Based on Pepco’s measurement, all ten feeders analyzed could fit an average residential PV installation for every single customer on that feeder. Electrify DC’s dynamic hosting capacity measurement, however, shows a much lower hosting capacity, with three of the ten feeders essentially at capacity.

Pepco was unable to provide high resolution time series data stating that it is burdensome to collect and maintain such high-resolution data. Although Pepco is investing in some elements of smart grid planning like high-resolution telemetry demonstrating its awareness that further visibility into the grid is needed, its investment is limited to only network feeders. At a more fundamental level, Pepco has also stated they do not maintain asset metadata like the age and model for individual grid components like transformers, hindering the ability to accurately model and assess the reliability of key grid components. The absence of both high-resolution operational data and key asset metadata underscores the critical need for investment in real-time monitoring to be able to avoid blind spots during grid operation. Smart grid planning and investment is urgently needed to operate the grid safely, conduct accurate analyses, and increase DER adoption.

Electrify DC found that Pepco does not explicitly take into account behind-the-meter batteries when analyzing hosting capacity. Pepco has stated they only account for behind-the-meter batteries when analyzing hosting capacity if the batteries are capable of increasing the minimum daytime load on a feeder. However, batteries are used to increase hosting capacity by off-loading peak load and storing excess solar generation. Measuring and encouraging energy storage presents an opportunity to increase hosting capacity and enhance grid flexibility.

Electrify DC’s survey found that residents’ demand for solar is strong with over 86% of responders who did not yet have solar expressing interest in it. More than one in three respondents want to know how they can become net producers of energy and sell it back to the grid which indicates consumers are moving towards becoming “prosumers.”