The Observer spoke with several energy industry professionals with experience in the development and management of utility-scale energy projects to understand the general context for the types of large-scale solar projects being proposed for Jefferson County (summarized below). We also researched the specific topography of the local power grid and land to understand both the potential and constraints for these types of solar projects in Jefferson County.
The areas shaded in orange on the map below represent the areas in Jefferson County most likely to meet the criteria for commercial-scale solar projects (described below). The indicated areas exclude parcels that include wetlands, are densely wooded, in farmland protection, or already developed with housing.
The 138kV Grid in Jefferson County
A Typical Project Timeline & Criteria
It takes 2 to 3 years to obtain approvals from the local grid operator (PJM Interconnection in WV) and the state Public Services Commission before any construction can begin.
A project developer must have a lease or purchase agreement with a landowner before beginning the approval process with the grid operator (typically an option agreement conditioned on project approval). In most jurisdictions the project developer does not apply for a use permit until later in the process (usually 2 years in, after the grid and state regulatory approvals). Local jurisdictions typically follow a condidional use permitting process for these types of projects.
These types of projects would connect to 138,000 volt transmission lines. The 500,000 volt lines on the larger towers (see image) or the smaller lines that connect commercial areas and neighborhoods are not suitable connections for these types of projects.
The ideal project location is flat land without trees or rocks, with a clear southern exposure. Large-scale generation projects are typically built close to transmission lines with a new substation and/or upgrades to existing substations (depending on the proximity and configuration of the project).
Tied To The Line
Direct access to a transmission line is the key criteria for locating these types of projects. Private developers (unlike public utility companies) cannot rely on eminent domain to place towers and lines across lands they do not own (or lease) and the cost of building lines is on the order of a million dollars per mile. This criteria effectively narrows the potential areas for projects to parcels (or groups of adjacent parcels) located under an existing transmission line.
A Minimum Size
The financial feasibility of a project is directly related to its size — at a cost of $7 to $9 million to build a new substation to connect into the transmission line, the minimum viable project size would be in the neighborhood of 70 MW (megawatt of energy generation) to justify that investment, given current land costs, panel costs, and current market rates for electricity generation. With current technologies, a fixed-panel system would require 4 acres per MW and a tracker-panel system would requires 6 acres per MW. These parameters suggests a minimum parcel grouping of 500 acres (assuming setbacks and buffers) for a tracker-panel system.
Capacity On The Line
The grid operator (PJM Interconnection) reviews all new projects to determine the feasibility and requirements for connecting to the grid. Each project is evaluated individually, but according to individuals familiar with the transmission grid, there is a limit on how much generation capacity can be connected to a line (think of the overloaded extension cord for your Christmas tree). It would be unlikely for PJM to allow more than 300 MW (megawatt of energy) to be connected to a single line segment. Given the size of the proposed projects, this constraint would limit the number of projects to 3 or fewer on each line segment.