There are significant backlogs of interconnection requests from renewable energy developers in local utility engineering departments in many parts of the country. Requests have been stuck for years as utilities struggle to complete complex interconnection studies. 

Since submitting a request is easy, even for large interconnections, a nontrivial number are submitted with minimal likelihood of getting built, which only adds to the problem. The Federal Energy Regulatory Commission has begun to intervene, issuing a notice of proposed rulemaking to streamline the process, adding requirements and penalties for transmission providers to complete studies on time and more stringent requirements for developers to prove they can build what is proposed.

Transmission work is typically needed for any large generator (greater than 20 megawatts) to interconnect the source to the grid. Smaller generators can usually connect to the local distribution system. Even when the generator is installed next to an existing transmission line, a small substation with equipment such as breakers, transformers and buswork is needed to rearrange the existing grid. This includes protection schemes designed to de-energize and re-energize the lines for any potential disturbance. 

The existing transmission lines must still be able to operate when the generating plant needs to be isolated for maintenance work or repairs. The simplest of these interconnections still requires adequate study by grid planners, project planning, detailed engineering design, construction and final commissioning work. Ramping up the amount of generation in the coming years will take some streamlining, along with an increase in engineering and construction resources in the very near future.

Some states and regions are leaning into this challenge aggressively, attempting to react rapidly to proposed generator interconnections while coming up with a more proactive, holistic and inclusive plan for transmission grid expansion and upgrades to enable renewable generation in optimal locations. 

In New York and beyond

For example, New York State conducted an expansive power grid study in 2020, in coordination with state regulatory and other agencies and all six major electric utilities. This study identified near-term priority transmission projects to support currently approved generator interconnections and longer-term projects and corridors to help facilitate pending or future renewables development. The report identified and recommended expedited approval for 52 near-term projects at a cost of $4.2 billion. This does not include several other planned multibillion-dollar transmission projects such as the 339-mile Champlain Hudson Power Express and the 175-mile line included with the Clean Path NY project. Plans are also underway to upgrade facilities in Long Island to access approximately 9,000 MW of offshore wind slated for installation in the next 5–15 years. 

On the national scale, there are broader studies and proposals that might ensure that much larger power flows can move over greater distances. This would allow for more flexible and efficient balancing of generation and load on a grid with significant penetrations of intermittent renewables. Areas of the country that have a natural abundance of hydro, solar or wind resources can produce far more energy without having to be curtailed as often. There are a variety of ideas for a national HVDC network, like those from the National Renewable Energy Lab and the Energy Systems Integration Group, which would create high-capacity ties between the separated interconnections. 

These new proposals would also leverage expanded offshore wind generation on both coasts and include significant expansion of the existing AC transmission networks in each interconnection. High-level estimates for a macrogrid exceed multiple trillions of dollars over a few decades. Daunting investments like this will require new ways of justifying and distributing costs across larger portions of the country, as well as changes to the traditional energy markets and regional grid operations. Much more coordination will be needed between the regional transmission organizations and independent system operators across the interconnections.

Massive challenges

There are many other headwinds for grand initiatives such as this, including the challenge of getting new transmission lines sited and built, especially when the proposed lines cross through regions that do not directly benefit from them. Local opposition may prevent or delay the projects from proceeding, causing painful expense write-offs of a few hundred million dollars for the companies.