Renewable Energy Alphabet Soup
If you are new to renewable energy projects, you must have come across abbreviations and acronyms that you had to look up to figure them out. In this blog post, we create a civil-engineering-biased glossary of such abbreviations and acronyms with their meanings. If we misstate a definition or if you would like to add something to the list, feel free to comment.
ACI - American Concrete Institute: Founded in 1904, ACI is a leading authority and resource worldwide for the development, dissemination, and adoption of consensus-based standards, technical resources, and educational programs related to concrete.
ACP - American Clean Power: America’s leading voice of today’s multi-tech clean energy industry.
AEP - Annual Energy Production: The amount of energy generated in a year.
AHJ - Authority Having Jurisdiction: The government authority having jurisdiction over a project.
ANSI - American National Standards Institute: Oversees standards and conformity assessment activities in the United States.
ARESCA - American Renewable Energy Standards and Certification Association: Provides administrative functions for the US Renewable Energy Standards community.
ASCE - American Society of Civil Engineers: ASCE is the nation’s oldest engineering society. ASCE stands at the forefront of a profession that plans, designs, constructs, and operates society’s built environment while protecting and restoring the natural environment.
ASD - Allowable Stress Design: A design approach that adopts a global factor of safety to account for all uncertainty.
ASR - Alkali–Silica Reaction (in concrete): A deleterious chemical reaction between some siliceous minerals in the aggregate and the alkalinity of the concrete that produces an expansive gel after the cement has set and causes internal pressure leading to expansion and cracking of the concrete.
ASTM - American Society for Testing and Materials: ASTM was established in 1898. Nowadays, ASTM International is a globally recognized leader in the development and delivery of voluntary consensus standards.
BESS - Battery Energy Storage System: A system that stores energy (typically from renewable sources or the grid) in batteries to be used when needed.
BMP - Best Management Practices: Cost-effective methods, controls and mitigation measures for reducing pollution and protecting water quality during construction and soil disturbing activities. BMPs are part of the SWPPP.
BOEM – Bureau of Ocean Energy Management: An agency of the U. S. Department of the Interior whose mission is to manage development of U.S. Outer Continental Shelf energy and mineral resources in an environmentally and economically responsible way.
BOP - Balance of Plant: In the wind energy sector, the BOP is everything in the farm except for the wind turbines.
BOQ: Bill of Quantities: Quantities of materials making up a given design used for estimating and project pricing.
BOS - Balance of Systems: The Balance of System (BOS) for a PV solar energy project encompasses all components of a photovoltaic system other than the photovoltaic panels.
C&I: Commercial and Industrial (market).
CAPEX - Capital Expenditures: Capital costs to develop and build a project.
CF - Capacity Factor: The ratio of the average power output of wind turbine and its maximum power capacity. Quoting online sources, capacity factor of land based wind in the U.S. ranges from 21% to 52% and averages 35%. This should not be a surprise knowing that the theoretical maximum efficiency of a turbine (known as the Betz Limit) is about 59%. Most turbines extract about 50% of the energy from the wind that passes through the rotor area.
CFA - Continuous Flight Auger: Continuous flight auger-cast piling is also known as auger-cast piling and it consists of creating a concrete pile by using a continuous flight auger to excavate the pile hole and injecting concrete through the hollow auger shaft of the auger as the auger is pulled out of the ground.
CHP - Combined Heat and Power: CHP, also known as cogeneration, is the concurrent production of electricity or mechanical power and useful thermal energy (heating and/or cooling) from a single source of energy and using a variety of fuels, both fossil and renewable-based.
CM - Condition Monitoring: Systematic data collection and assessment to identify the cause(s) of changes in the data being collected.
CMS - Condition Monitoring System: A data collection system to monitor the operation conditions of an asset (drive train of a wind turbine, vibrations of a structure, etc.)
COD - Commercial Operation Date (of a Project): the start date of commercial operation for a project.
COV - Coefficient of Variation: A statistical measure defined as standard deviation divided by the mean.
CPT - Cone Penetration Test: A standard geotechnical probing method consisting of pushing a cone-shaped instrument and recording soil resistance (ASTM D3441). The test provides a continuous vertical record and can even measure pore water pressure.
CSP - Concentrating Solar Power: CSP technology uses many mirrors to reflect and focus sunlight into one point to heat a working fluid that drives a turbine or heat engine/generator for electricity production. CSP is also referred to as Solar Thermal Electricity (STE).
CCS - Carbon Capture and Storage/Sequestration: A method of capturing carbon dioxide formed during power generation and industrial processes and storing it so that it is not emitted into the atmosphere.
DEF - Delayed Ettringite Formation: delayed formation of the mineral ettringite (a normal product of early cement hydration) resulting in expansion and cracking of concrete. DEF is caused by high early heat of hydration (temperatures above 70 to 80 degrees centigrate).
DEL - Damage Equivalent Load:
DG - Distributed Generation: Generation from renewable energy plants, typically 30MW or less, that deliver electricity straight to a distribution, rather than a transmission, grid (typically an autonomous microgrid).
DLC - Design Load Case: One of the many load cases considered in the design of the structure or its foundation.
eBOS - Electrical Balance of System: All the components in a solar park that are needed to carry electric current from the modules to the grid.
EIA - Environmental Impact Assessment: The assessment of the environmental consequences of a project.
EIA - US Energy Information Administration: A US government agency that collects, analyzes, and disseminates energy information to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and the environment.
EOR - Engineer-of-Record: Registered design professional in responsible charge of a certain engineering scope of a project.
EPC Contractor - Engineer-Procure-Construct Contractor: The contractor (a construction or construction management company) that assumes the scope of detailed engineering, procurement and construction of a project or part of a project.
EV - Electric Vehicle: A vehicle that runs on electricity.
FLS - Fatigue Limit State: The state of fatigue failure due to stress level, stress variation or number of cycles.
GEOR - Geotechnical Engineer-of-Record: Geotechnical engineer for a given project.
GM - Ground Modification: Any technique for modifying (improving) the capacity of ground materials to support foundations and superstructures.
GPR - Ground Penetrating Radar: A non-intrusive geophysical technology that uses radar pulses to image the ground subsurface.
GSU - Generator Step-up (GSU) Transformers: The GSU is the link between the power plant and the transmission network. It is a critical component of a power plant used to convert the power plant voltage level up to the interconnecting voltage level.
GWP - Global Warming Potential: A measure of how much infrared thermal radiation a greenhouse gas absorbs over a given time frame after being added to the atmosphere
GWT - Groundwater Table: Typically, a reference to depth of the groundwater table.
HH - Hub Height: The hub height of Horizontal Axis Wind Turbine (HAWT) is the height from ground level to the horizontal axis.
HAWT - Horizontal Axis Wind Turbine: The most common model of wind turbines where the blade(s) spin(s) around a horizontal axis.
IBC - International Building Code: Design code produced by the International Code Council.
ICC - Installed Capital Cost: The actual total cost that would be paid to complete a project including materials, labor, taxes, and overhead.
IEC - International Electrotechnical Commission: An international standards development body.
IFC - Issued-for-Construction: The state of the set of documents (drawings and specification) corresponding to being approved for construction.
IOU - Investor-Owned Utility: A private company that that provides utility services, typically over a defined service territory and using their own infrastructure and equipment.
IPP - Independent Power Producer: A non-public entity that owns electric power generation facilities, also called a Non-Utility Generator (NUG).
ISO- Independent System Operator: An independent and federally regulated entity that coordinates regional electrical transmission to ensure grid reliability and non-discriminatory grid access.
ISO - International Standards Organization: An international standards development body.
ITC - Investment Tax Credit: A federal income tax credit for certain types of renewable and clean energy projects.
LCA - Life Cycle Assessment:
LCC - Low Cabon Concrete: Concrete produced in compliance with Global Warming Potential (GWP) reduction provisions.
LCOE - Levelized Cost of Energy: An economic measure used to compare the lifetime costs of energy generation (typically electricity) across various generation technologies
LCOH - Levelized Cost of Hydrogen: An economic measure used to compare the lifetime costs of producing hydrogen across various production technologies.
LNTP - Limited Notice to Proceed: An official notice to proceed with executing limited parts of a project or scope.
LOTO - Lock-out-Tag-out: A standardized practice (within an organization) and documented set of procedures to safeguard workers from hazardous energy releases.
LRFD - Load and Resistance Factor Design: A design approach where separate safety factors are assigned to loads and resistance.
LSD - Limit States Design: A design approach based on meeting one or more limit states.
LTE - Lifetime / Life Extension: Extending the life of an asset beyond its original design life based on an assessment of its Remaining Useful Life (RUL).
MASW - Multi-Analysis of Surface Waves: a geophysical survey method that provides a depth profile of shear wave velocity, compression wave velocity, etc.
MCS - Monte Carlo Simulation: A simulation consisting of random generation of realizations.
MDD - Maximum Dry Density: The maximum dry density of a soil sample compacted using a specified compaction effort (typically Standard Proctor or Modified Proctor).
MSA - Master Services Agreement: An agreement that would apply to multiple projects.
NDA - Non-Disclosure Agreement: An agreement governing rules for confidentiality and information protection between two parties.
NDE - Non-Destructive Evaluation: An evaluation using non-destructive testing methods.
NDT - Non-Destructive Testing: Testing using non-destructive methods.
NREL - National Renewable Energy Laboratory: A national laboratory of the U. S. Department of Energy that strives to achieve a clean energy future for the world through a mission consisting of leading research, innovation, and strategic partnerships to deliver solutions for a clean energy economy.
NTP - Notice to Proceed: An official notice by owner/manager to EPC to proceed with construction, or by to Engineer to proceed with engineering services.
NUG - Non-Utility Generator: A non-public entity that owns electric power generation facilities, also called an Independent Power Producer (IPP).
OE - Owner Engineering: Engineering (review) services provided to project owners and investors. Also called Independent Engineering (IE).
OEM - Original Equipment Manufacturer: In the case of wind projects, typically turbine manufacturers. In general, the manufacturer of a given piece of equipment.
O&M - Operation and Maintenance: Typically an O&M building on a site or the O&M operator.
OMC - Optimum Moisture Content: The water content of a soil soil sample that produces the maximum dry density for a specified compaction effort.
OPEX - Operational Expenditures: Costs to operate a project or facility.
PLT - Pile Load Test: Subjecting a pile to load and measuring displacements.
POI - Point of Interconnection: The physical location where a generation entity's interconnection facilities connect to the Transmission Service Provider's (TSP's) transmission facilities.
POU - Publicly-Owned Utility: A non-profit organization that supplies and delivers services to the public.
PPA - Power-Purchase Agreement: An agreement to purchase power from a project.
PPE - Personal Protective Equipment: Safety equipment required for a specific task.
PTC - Production Tax Credit
PTI - Post-Tensioning Institute: A non-profit organization that promotes and advances the post-tensioning industry through education and technical leadership.
PV - Photovoltaic: A system or process that coverts sunlight into electricity.
QA/QC - Quality Assurance / Quality Control: The collection of processes to achieve construction to specified quality.
RBD - Reliability-Based Design: A design methodology that considers, in a quantifiable manner, the risks and uncertainties associated with performance, geometry, materials, and loads.
RCA - Root Cause Analysis: A standardized process to identify root cause(s) of an issue. See IEC 62740 as an example standard.
RDP - Registered Design Professional: A person who is licensed or registered to practice their design profession.
REC - Renewable Energy Certificate: A market-based instrument to document that energy flowing into the power grid comes from a clean, renewable power source.
RFC - Rain-Flow Counting (algorithm): A method for determining the number of fatigue cycles present in a load-time history.
RFI - Request for Information: A formal request of information, typically from a construction site to the engineer.
RNA - Rotor-Nacelle Assembly: Part of the wind turbine that consists of the rotor (blades and nose cone) and nacelle.
RPS - Renewables Portfolio Standard: A set of policies, developed at a country, state or local level, that require that a specified percentage of the electricity utilities sell comes from renewable resources. Typically, the policies aim to diversify energy resources, promote domestic energy production and encourage economic development.
RTO - Regional Transmission Organization: An organization that coordinates, controls and monitors the operation of the electrical power system. In the United States, an RTO is formed at the approval of the Federal Energy Regulatory Commission (FERC) for an area that a encompasses a single state or multiple states.
RUL - Remaining Useful Life: Estimated time an operating asset will continue to operate before requiring major repair, replacement or decommissioning.
SCADA - Supervisory Control and Data Acquisition: A computer-based system for gathering and analyzing real-time data to monitor and control equipment or process.
SCPT - Seismic Cone Penetration Test: A standard geotechnical probing method similar to the CPT but with the added capability of measuring down-hole shear wave propagation at 1-meter intervals of the probed depth.
SDC - Seismic Design Category: A classification assigned to a structure based on its occupancy category and the severity of the design earthquake ground motion as defined by ASCE 7.
SEIA - Solar Energy Industry Association: The national trade association for the U.S. solar industry.
SHM - Structural Health Monitoring: A non-destructive method of evaluating the structural health of structures. SHM uses sensors to analyze, record, and localize the conditions of loading and damage to structures.
SLS - Serviceability Limit State: A state of design beyond which a structure or structural element loses functional operation because of violation of certain criteria such deflection, vibration, durability, or cracking.
SPT - Standard Penetration Test: A standardized test for sampling soil material and measuring soil resistance in a boring hole (ASTM D1586).
SSAL - Site Specific Assessed Life: Fatigue life of a component or asset assessed based on site-specific conditions.
SWPPP - Storm Water Pollution Prevention Plan: A site-specific, written document developed to identify potential sources of stormwater pollution at a construction site and outline the Best Management Practices (BMPs) employed to reduce pollutants in stormwater discharges from the site.
SWT - Small Wind Turbine: The American Clean Power Association defines a small wind turbine as an electricity-producing wind turbine having a Peak Power of 150 kW or less.
TLM - Through-Life Management: A system of managing assets (mainly wind farms) where condition monitoring and intervention during operation are an integral project component.
TSP - Transmission Service Provider: The entity (electric utility, municipally-owned utility, electric cooperative, etc.) that manages the transmission tariff and provides transmission services to transmission customers.
ULS - Ultimate Limit State: The maximum load or force a structure can withstand without collapsing or sustaining irreversible damage.
VMS - Vibration Monitoring System: A system to monitor vibrations at specific points of a system, used typically for early detection of damage or faults.
VPPA - Virtual Power Purchase Agreement: An agreement to purchase power but not necessarily from a specific project.
WEC - Wind Energy Converter: The electro-mechanical plant or system that converts wind energy into electricity. The same as Wind Turbine Generator (WTG).
WTG - Wind Turbine Generator: The electro-mechanical plant or system that converts wind energy into electricity. The same as Wind Energy Converter (WEC).