Energy planning and land-use decisions come with their own language: dockets, CPCNs, megawatts, intervenors. This glossary explains the terms you’ll see on our site, in public notices, and in news coverage, in plain words. If you come across a term that isn’t here, email us at info@preserveruralmaine.org and we’ll add it.
A · C · D · E · F · H · I · K · L · M · N · O · P · R · S · T · V · W
A
Abutter — A property owner whose land borders a project site, road, or corridor. Abutters often receive formal notice of proposed projects and may have specific rights to comment.
C
Capacity factor — How much electricity a power plant actually produces over a year, compared with what it could produce running at full output all the time. A wind project rated at 100 megawatts with a 35% capacity factor produces, on average, about 35 megawatts.
CETU (Cluster Enabling Transmission Upgrade) — ISO-NE’s term for the transmission needed to connect a group, or “cluster,” of new power projects in one area to the regional grid.
Comprehensive plan — A town’s long-range plan for land use, growth, and community character. In Maine, zoning and many land-use ordinances must be consistent with the town’s comprehensive plan.
CPCN (Certificate of Public Convenience and Necessity) — Approval from the Maine Public Utilities Commission that a new transmission line is needed and in the public interest. A utility generally needs a CPCN before building a major line, and before it can use eminent domain for it.
D
Decommissioning — Removing a facility at the end of its life and restoring the land. Ordinances and permits often require a decommissioning plan and money set aside up front to pay for it.
DEP (Department of Environmental Protection) — The state agency that issues environmental permits for many energy and development projects, including those in the Northern Maine Renewable Energy Development Program.
Distribution line — The lower-voltage lines on wooden poles along most roads that deliver electricity to homes and businesses. Compare transmission line.
Docket — The official case file for a matter before a regulatory agency such as the PUC. Each docket has a number (for example, 2026-00033), and all filings, orders, and public comments are posted to it.
DOER (Department of Energy Resources) — Maine’s state energy agency, formerly the Governor’s Energy Office. It leads state energy planning and studies such as the Maine Transmission Infrastructure Study.
E
Easement — A legal right to use part of someone else’s land for a specific purpose, such as running a power line, while the landowner keeps ownership. Easements are usually permanent and transfer with the property when it is sold.
Eminent domain — The power of the government, or a utility it authorizes, to take private property, or an easement on it, for public use in exchange for compensation. Maine law limits how transmission and distribution utilities can use eminent domain, including protections for homes.
EUT Committee (Energy, Utilities and Technology Committee) — The joint committee of the Maine Legislature that holds public hearings and work sessions on most energy and utility bills.
F
FOAA (Freedom of Access Act) — Maine’s public records law. It gives anyone the right to request records from state and local government agencies, with some exceptions.
H
Home rule — The authority of Maine towns to adopt their own ordinances on local matters, unless state law specifically limits that authority.
HVDC (High-voltage direct current) — A way of moving large amounts of electricity over long distances, often with fewer losses than standard alternating current (AC) lines. HVDC lines can be buried or run underwater more easily than AC lines, but they require large converter stations at each end.
I
Interconnection — The process and equipment for connecting a new power plant to the electric grid. Interconnection studies determine what grid upgrades a new project needs.
Intervenor — A person or organization granted formal party status in a PUC proceeding. Intervenors can file evidence, ask questions of other parties, and appeal decisions; members of the public who are not intervenors can still file comments.
ISO-NE (ISO New England) — The independent, non-profit organization that operates the electric grid and wholesale electricity markets for the six New England states, and plans the region’s transmission system.
K
kV (kilovolt) — One thousand volts. Large transmission lines in Maine typically carry 115 kV or 345 kV; the lines along most roads carry far less.
L
LD (Legislative Document) — The number given to a bill in the Maine Legislature, such as LD 2087. Numbers start over with each two-year Legislature.
Load — The amount of electricity customers use at a given time. A load zone is an area of the grid used for pricing and planning.
LTTP (Longer-Term Transmission Planning) — ISO-NE’s process for planning transmission to meet the New England states’ long-range energy needs, including its competitive request for proposals to build new transmission.
LUPC (Land Use Planning Commission) — The state agency that handles land-use planning and permitting in Maine’s unorganized territories and some towns without their own planning.
M
Megawatt (MW) and megawatt-hour (MWh) — A megawatt measures how much power something can produce or use at one moment. A megawatt-hour measures energy over time: one megawatt running for one hour. Project sizes are given in MW; electricity bills and usage are counted in kilowatt-hours (one-thousandth of a MWh).
Moratorium — A temporary local ordinance that pauses certain kinds of development while a town studies the issue and writes permanent rules. Maine law sets requirements for when and how long a town may adopt one.
N
NESCOE (New England States Committee on Electricity) — An organization representing the six New England governors on regional electricity matters. NESCOE works with ISO-NE on regional transmission planning, including the LTTP process.
NMISA (Northern Maine Independent System Administrator) — The organization that runs the electric system in northern Maine, which is not directly connected to the ISO-NE grid.
Northern Maine Renewable Energy Development Program — A program created by Maine law in 2021 (revised in 2024) to build transmission connecting new renewable generation in Aroostook County and the NMISA area to the rest of the grid. The PUC runs the procurement. See our Northern Maine Transmission & Wind page.
O
OPA (Office of the Public Advocate) — The state office that represents Maine’s utility customers in PUC cases and other proceedings.
Ordinance — A local law adopted by a town, usually at town meeting or by the town council. Land-use ordinances can address where and how development happens, within the limits of state law.
Ought to Pass / Ought Not to Pass — The recommendations a legislative committee votes on after reviewing a bill. “Ought Not to Pass” usually means the bill will not move forward.
P
PAC (Planning Advisory Committee) — ISO-NE’s open stakeholder forum for transmission planning. Meeting materials are posted publicly, and members of the public may attend.
PPA (Power Purchase Agreement) — A long-term contract to buy electricity from a power plant at set terms. Under Maine’s procurements, utilities sign these contracts and the costs are passed on to ratepayers.
Protective order — An order limiting who can see confidential information filed in a case, such as bid prices. Parties who sign the order can view the information; the public generally cannot.
PUC (Public Utilities Commission) — The three-member state commission that regulates Maine’s utilities: it sets rates, runs energy procurements, and approves major transmission lines.
Public hearing — A scheduled meeting where anyone can speak or submit written comments on a bill, rule, or project before a decision is made.
R
Ratepayer — A customer who pays an electric utility bill. Many energy decisions are paid for by ratepayers through charges on their bills.
RFI (Request for Information) — An early step in which an agency asks the public and industry for information before designing a procurement.
RFP (Request for Proposals) — A formal invitation for companies to submit competing bids to build or supply something, such as a transmission line or new generation.
Right-of-way (corridor) — The strip of land a utility controls, usually through easements, to build and maintain a line. Rights-of-way are kept clear of tall trees.
S
Substation — A fenced facility with transformers and switching equipment that changes voltage and connects lines together. New transmission often requires new or expanded substations.
T
Testimony — Written or spoken comments given to a legislative committee or agency. In the Maine Legislature, testimony can be for, against, or “neither for nor against” a bill.
Transmission line — A high-voltage line that carries large amounts of electricity over long distances, usually on tall steel or wooden structures in a cleared corridor. Compare distribution line.
TSA (Transmission Service Agreement) — A long-term contract that pays a developer to build and operate a transmission line, with costs typically recovered from ratepayers.
V
Vegetation management — How a utility keeps its right-of-way clear of trees and brush, by mowing, cutting, or applying herbicides. Landowners can ask utilities about their methods and schedules.
W
Work session — A legislative committee meeting where members discuss a bill, propose changes, and vote on a recommendation. The public may watch but usually cannot speak.
Last reviewed: October 2026