The Virginia Board of Companies has approved the continued use of grid safety devices, which may result in excessively high financial costs for medium-sized solar projects.

In early February, the SCC in the state allowed utility company Dominion Energy to continue requiring direct transmission trips (DTT) for interconnected solar and storage projects, which can prevent distributed energy from generating electricity when operating independently of the grid or when it is not necessary to "islander" power generation.

Generating isolated electricity in this way may pose safety risks, such as keeping collapsed wires energized during power outages. But critics of DTT argue that existing utility and inverter safety protocols can mitigate these risks.

DTT is suitable for interconnected solar projects with a power of 250 kW or higher. The Interstate Renewable Energy Commission (IREC) believes that the cost of implementing DTT may hinder the implementation of solar and energy storage projects. In a study published by IREC in July, it was reported that DTT communication components (such as radio or fiber optic cabling) could cost tens of thousands to hundreds of thousands of dollars, while solar project developers would need to spend tens of thousands to hundreds of thousands of dollars to purchase them.

Brian Lydic, Chief Regulatory Engineer at IREC, said: "After years of industry and utility collaboration, decades of research, and billions of watts of interconnection in other regions, this is an incredible and disappointing result, all of which prove that the use of DTT in inverter DER applications is arbitrary. ”

In that report, IREC estimated that the "unintentional island" scenario, which could pose security risks, is unlikely to occur - a situation that "only occurs once every 3800 to 10000 years".

The report states that these claims are supported by empirical data, as there has only been one recorded sustained island event in North America that occurred under extremely unusual transmission levels, and typical DTT schemes cannot address this issue. ”

Although Virginia's requirement for DTT has hindered its community and commercial solar market, other states in the region are installing solar energy of this scale at a faster pace.

Disappointingly, during a period of historic energy price increases, Virginians in the world's data center capital will have fewer opportunities to obtain community DER energy cost savings, "said Shay Banton, IREC regulatory project engineer and head of energy justice