Tobie Green Energy

Wind Energy Terms

Any individual, business, farmer or school considering in investing in a wind energy project will need to be familiar with a few key energy terms.  These are not precise legal definitions.  Rather, this information is provided to give end users a sense of how these terms are typically used within the power industry.

Anemometer:  A device that measures wind speeds.

Commercial-Scale Wind Project:  Wind projects larger than 100kW

Community Wind:  An approach to wind energy development that emphasizes local ownership, involvement, and benefits.

Distributed Generation:  Electricity that is generated close to where it is used.  Includes generation for on-site use.  

Distribution Lines:  Low voltage power lines used to distribute electricity over relatively short distances from a power generation facility or substations to consumers.

Electric Grid:  A system of transmission and distribution lines connecting synchronized power providers and consumers.  Interconnects and facilitates the distribution of electricity to consumers.  

Electric Utility:  An entity that owns or operates facilities for the generation, transmission, distribution, or sales of electric energy to the public.  Usually operates with some form of legal monopoly over the electric services in the geographic area.

Federal Energy Regulatory Commission (FERC):  An independent regulatory agency within the U.S. Department of Energy having jurisdiction over, among other things, interstate electricity sales and wholesale electricity rates.

Independent Power Producer:  An entity which generates electricity, but is not an electric utility.

Independent System Operator (ISO):  An entity organized by the electric industry to control and administer non-discriminatory access to electric transmission in a region or across several electric systems.

Interconnection:  The physical and electrical interface between a power generator (like a wind turbine) and electric distribution or transmission lines.  
 
Kilowatt Hour (kWh):  The basic unit of measurement upon which the price of electricity is based.  In other words, customers pay per kWh of electricity used.  One kWh is equal to 1 kilowatt (1,000 watts) of power used for 1 hour.  

Megawatt (MW):  A unit of electrical power equal to 1 million watts or 1,000 kilowatts.

Meteorological Tower Agreement (“MET” tower agreement):  A contract through which a landowner agrees to allow a wind developer to install wind testing equipment on their land.

Net Excess Generation:  The amount of electricity produced by a wind turbine constructed to meet on site energy needs that exceed the farm’s or household’s immediate demands.  Usually calculated on a monthly basis.

Net Metering:  A method of measuring, on a single electric meter, the amount of electricity consumed from the electric grid and the amount of electricity produced on site and put onto the grid.  Allows an electric consumer to accumulate credit for net excess generation that flows back onto the grid.  

Parallel Generation:  Electricity generated on the customer’s side of the electric meter.  Sometimes called cogeneration.  

Power Purchase Agreement (PPA):  A contract though which a power purchaser (like a utility) aggress to buy electricity from a power generation facility (like a wind project).

Production Tax Credit (PTC):  A government incentive for wind energy development that reduces income tax liability based on the amount of renewable energy generation.  

Public Utilities commission (PUC) or Public Service Commission (PSC):  A state’s energy regulatory agency, typically having jurisdiction over, among other things, retail electricity sales to customers and on site power generation projects.  

Public Utility Regulatory Policies Act (PURPA):  A federal statute that, among other things, ensures a market for the electricity produced by small renewable energy generators (called qualifying facilities).

Qualifying Facility:  A renewable energy generator, as defined by the Public Utility Regulatory Policies Act, with a nameplate capacity of no more than 80 MW

Rated Power:  The amount of electricity a generator is expected to produce when operating at maximum performance.  If a wind turbine has a rated power of 1,000 kW, then that wind turbine is expected to produce 1,000 kW of energy per hour of operation, when running at its maximum performance.   

Renewable Energy Credit (REC):  The environmental attributes of electricity generated from renewable sources, like wind, that are tracked or sold separately from the electricity itself.

Small Scale Wind Project:  Definitions vary, but for the purposes of this guide, wind projects of 100kW and smaller are small scale.  

Transmission:  The transfer of electrical power from one place to another at high voltages.

Transmission Lines:  High-voltage power lines used to move electricity over relatively long distances from a power generation facility to a substation or other distribution point.