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• A
  • automatic voltage regulator
    • An Automatic Voltage Regulator (AVR) is a device, which provides brownout protection and
      surge suppression in a single cost-effective unit. AVRs also correct for over voltages and are
      sometimes called line conditioners.  They are perfect for powering voltage sensitive equipment
      from backup generators that experience voltage fluctuations during load changes.
  • AVR
    • Automatic Voltage Regulator
• B
  • BOOT
    • Build-Operate-Own-Transfer
  • BOT
    • Build-Operate-Transfer (BOT) is a form of project financing, wherein a private entity receives
      a franchise from the public sector to finance, design, construct, and operate a facility for a
      specified period, after which ownership is transferred back to the public sector. During the
      time that the project proponent operates the facility, it is allowed to charge facility users
      appropriate tolls, fees, rentals, and charges stated in their contract to enable the project
      proponent to recover its investment, and operating and maintenance expenses in the project.
      In some countries, such as Canada, the term used is Build-Operate-Own-Transfer (BOOT).
      BOT is now also used in the off-shoring and outsourcing of knowledge work. In these cases
      there is usually no government or public funding involved. Typically a Western customer
      contracts with an India or China vendor and the vendor builds and operates a customer call
      center or other business process for an extended period of time. But the client retains the right
      to take over the operate ("transfer") at any time based on certain conditions and certain payments
      to the offshore partner.
  • bus bar
    • A bus bar refers in electrical power distribution to thick strips of copper or other material that
      conduct electricity around a switchboard, distribution board, substation, or other electrical
      apparatus.
      The size of the busbar determines the maximum amount of current that can be safely carried.
      Small distribution boards or consumer units may have busbars which have a cross sectional
      area of as little as 10 mm² but large electrical substations may use metal tubes of 50 mm
      or more in diameter as bus bars.
      Bus bars are typically either flat strips or hollow tubes as these shapes allow heat to dissipate
      more efficiently due to their high surface area to cross-sectional area ratio. The skin effect
      makes AC bus bars more than about 8 mm (1/3 in) thick inefficient.
      Bus bars are usually suitably insulated for the voltage which they carry. The busbar may either
      be supported on insulators, or else insulation may completely surround the busbar. Bus bars
      are protected from accidental contact either by being surrounded in a sheet metal enclosure
      or by being placed out of normal reach. Neutral bus bars may also be insulated. Earth busbars
      are typically bolted directly onto any metal chassis of their enclosure.
• D
  • Danvest Energy A/S
    • Previous company, which is now called Vestesen A/S
  • Danvest system
    • This is the wind/diesel system tested and approved by Risø National Laboratory, Denmark.
  • DDB
    • Dynamic Dump load Bank
  • DDL
    • Dynamic Dump Load
  • desalination
    • Desalination or desalinization refers to any of several processes that remove the excess salt
      and other minerals from water in order to obtain fresh water suitable for animal consumption
      or irrigation, and if almost all of the salt is removed, for human consumption, sometimes
      producing table salt as a by-product.
  • DPP
    • Diesel Power Plant
  • dump load
    • This is a resistive load designed to dissipate the excess power generated by the generation system.
      The dump load is designed so the capacity will be the rated power of a wind turbine + 30% Another
      way to determine the dump load power is to take the maximum wind turbine kW minus minimum
      consumer demand + 20% The dump load power can vary depending on the installation.
• F
  • flickering
  • fluctuation
• H
  • HFO
    • Heavy Fuel Oil
  • high wind penetration
    • click here
  • HPS
    • Hybrid Power System
  • Human Machine Interface
    • The HMI/SCADA industry was essentially born out of a need for a user friendly front-end to a
      control system containing programmable logic controllers (PLC). While a PLC does provide
      automated, pre-programmed control over a process, they are usually distributed across a plant,
      making it difficult to gather data from them manually. Additionally, the PLC information are usually
      in a crude user-unfriendly format. The HMI/SCADA gathers information from the PLCs via some
      form of communication method, and combines and formats the information. Since the early 1990s
      the role of SCADA systems in large civil engineering solutions has changed, requiring them
      to perform more operations automatically. A sophisticated HMI may also be linked to a database
      to provide instant trending, diagnostic data, scheduled maintenance procedures, logistic information,
      detailed schematics for a particular sensor or machine, and expert-system troubleshooting guides.
      Since about 1998, virtually all major PLC manufacturers have offered integrated HMI/SCADA systems,
      many of them using open and non-proprietary communications protocols. Numerous specialized
      third-party HMI/SCADA packages offering built-in compatibility with most major PLCs have also
      entered the market, allowing mechanical engineers, electrical engineers and technicians to configure
      HMIs themselves, without the need for a custom-made program written by a software developer.
  • hydrophore
    • An instrument used for the purpose of obtaining specimens of water from any desired depth,
      as in a river, a lake, or the ocean.
  • Hz
    • Hertz
• I
  • IPR
    • Intellectual Property Right
• K
  • kW
    • Kilowatt: 1,000 kW = 1 MW
  • kWh
    • Kilowatt-hour: the kilowatt-hour (symbolised kWh) is a unit of energy equivalent to one kilowatt
      (1 kW) of power expended for one hour (1 h) of time. The kilowatt-hour is not a standard unit
      in any formal system, but it is commonly used in electrical applications.
• L
  • LFO
    • Light Fuel Oil
  • LLU
    • Low Load Unit
• M
  • MW
    • Megawatt: 1 MW = 1,000 kW
• O
  • osmosis
    • Osmosis is the diffusion of a solvent through a selectively-permeable membrane from a region
      of low solute concentration to a region of high solute concentration, or in other words, from a
      high water concentration to a low water concentration. The higher the solute concentration the
      lower the water concentration will be. The selectively-permeable membrane is permeable to
      the solvent, but not to the solute, resulting in a chemical potential difference across the membrane
      which drives the diffusion. That is, the solvent flows from the side of the membrane where
      the solution is weakest to the side where it is strongest, until the solution on both sides of
      the membrane is of the same strength.
• P
  • PFP
    • Partnership Facility Programme
  • PHE
    • Plate Heat Exchanger
  • photovoltaic
    • Description of PV
  • PLC
    • What is a PLC?
      A Programmable Logic Controller, or PLC, is more or less a tiny computer with an built in
      operating system (OS).
      This OS is highly specialized to handle incoming events at real time i.e. at the time of their occurence.
      The PLC has input lines where sensors are connected to notify upon events (e.g. temperature
      above/below a certain level, liquid level reached, etc.) and it has output lines to signal any reaction
      to the incoming events (e.g. start an engine, open/close a valve, etc.) The system is user
      programmable. It uses a language called "Relay Ladder" or "Relay Ladder Logic". The name of
      this language implies the fact that the control logic of the earlier days, which was built from relays,
      is being simulated.
      
      The PLCs purpose in life
      The PLC is primarily used to control machinery. A program is written for the PLC which turns on
      and off outputs based on input conditions and the internal program. In this aspect, a PLC is
      similar to a computer. However, a PLC is designed to be programmed once, and run repeatedly
      as needed. In fact, a crafty programmer could use a PLC to control not only simple devices such
      as a garage door opener, but their whole house, including turning lights on and off at certain times,
      monitoring a custom built security system, ect.
      Most commonly, a PLC is found inside of a machine in an industrial enviornment. A PLC can run
      an automatic machine for years with little human intervention. They are designed with (hopefully)
      stable operating systems, and to withstand most harsh enviornments a PLC will encounter.
  • PPA
    • Power Purchase Agreement
  • PSA
    • Power Supply Agreement
  • PV
    • PhotoVoltaic
• R
  • reactive power
    • Engineers use three types of power to describe energy flow in a system:
      
      Real power (P)
      Reactive power (Q)
      Complex power (S); |S|, the modulus of complex power, is referred to as apparent power
      
      In the diagram, P is the real power, Q is the reactive power (in this case negative), and the
      length of S is the apparent power.
      
      
      
      The unit for all forms of power is the watt (symbol: W). In practice, however, this is generally
      reserved for the real power component. Apparent power is conventionally expressed in
      volt-amperes (VA) since it is the simple multiple of rms voltage and current. The unit for reactive
      power is given the special name "VAR", which stands for volt-amperes-reactive.
      Understanding the relationship between these three quantities lies at the heart of understanding
      power engineering. The mathematical relationship among them can be represented by vectors
      and is typically expressed using complex numbers
      S = P + jQ (where j is the imaginary unit)
      This complex value S is often referred to as the complex power.
      Consider an ideal alternating current (AC) circuit consisting of a source and a generalized load,
      where both the current and voltage are sinusoidal. If the load is purely resistive, the two
      quantities reverse their polarity at the same time; the direction of energy flow does not reverse;
      and only real power flows. If the load is purely inductive or capacitive, then the voltage and
      current are 90 degrees out of phase (for a capacitor, current leads voltage; for an inductor,
      current lags voltage) and there is no net power flow. This energy flowing backwards and
      forwards is known as reactive power. If a capacitor and an inductor are placed in parallel,
      then the currents caused by the inductor and the capacitor are in antiphase with each other
      and therefore partially cancel out rather than adding to each other. Conventionally, capacitors
      are considered to generate reactive power and inductors to consume it. In reality, the load is
      likely to have resistive, inductive, and capactive parts; and so both real and reactive power will
      flow to the load. The apparent power is the result of a naive calculation of power from the voltage
      and current in which the RMS voltage is simply multiplied by the rms current. Apparent power
      is handy for rough sizing of generators or wiring, especially when the power factor is close to 1.
      However, adding the apparent power for two loads will not give the total apparent power unless
      the two loads have the same phase difference between voltage and current.
  • reverse osmosis
    • The osmosis process can be driven in reverse with solvent moving from a region of high solute
      concentration to a region of low solute concentration by applying a pressure in excess of the
      osmotic pressure. This reverse osmosis technique is commonly applied to purify water.
      Sometimes the term forward osmosis is used for osmosis, particularly when used for rehydrating
      dried food using contaminated water.
  • rpm
    • Revolutions Per Minute
• S
  • SCADA
    • SCADA is the acronym for Supervisory Control And Data Acquisition. SCADA may be called
      Human-Machine Interface (HMI) in Europe. The term refers to a large-scale, distributed measurement
      (and control) system. SCADA systems are used to monitor or to control chemical, physical or
      transport processes.
  • SCADA system concept
    • The term SCADA usually refers to a central system that monitors and controls a complete site.
      The bulk of the site control is actually performed automatically by a Remote Terminal Unit (RTU)
      or by a Programmable Logic Controller (PLC). Host control functions are almost always restricted
      to basic site over-ride or supervisory level capability.

      
      
      
      Data acquisition begins at the RTU or PLC level and includes meter readings and equipment
      statuses that are communicated to the SCADA as required. Data is then compiled and formatted
      in such a way that a control room operator using the HMI can make appropriate supervisory decisions
      that may be required to over-ride normal RTU (PLC) controls. (A SCADA system includes all the pieces,
      HMI, controllers, I/O devices, networks, software, etc.)
      SCADA systems typically implement a distributed database which contains data elements called points.
      A point represents a single input or output value monitored or controlled by the system. Points can
      be either "hard" or "soft". A hard point is representative of an actual input or output connected to
      the system, while a soft point represents the result of logic and math operations applied to other
      hard and soft points. The point values are normally stored as value-timestamp combinations;
      the value and the timestamp when the value was recorded or calculated. A series of value-timestamp
      combinations is the history of that point.

      It's possible to purchase a SCADA system, or Distributed Control System (DCS) from a single supplier.
      It's also possible to assemble a SCADA system from components like Wonderware HMI, Allen-Bradley
      & GE PLCs, Ethernet communication devices, etc.
  • Stand-alone
    • Power system not connected to a grid
  • Switchgear
    • The term switchgear, used in association with the electric power system, or grid, refers to the combination
      of electrical disconnects, fuses and/or circuit breakers used to isolate electrical equipment. Switchgear is
      used both to de-energize equipment to allow work to be done and to clear faults downstream.
• W
  • WD
    • See under wind-diesel - click here to se more about wind-diesel.
  • WDS2 A/S
    • Company; WDS is a contraction of two things - Wind-Diesel Systems and Water-Desalination Systems.
  • wind-diesel
    • Wind-diesel (WD) is a way to make continuous power supply from wind turbines and diesel engines.
      WD-systems are made to isolated off grid locations. The system makes it possible to control the wind
      turbines connected to small isolated grids in such a way that so much wind power capacity can be
      installed that yearly fuel savings of 50-90% can be obtained. There are three test reports from Risø,
      which verifies the functionality of the system. When there sometimes is little wind and the wind energy
      production cannot cover the consumer demand, the WD-system will automatically make sure that the
      diesel engine works as a backup to the wind turbines, so the total wind and diesel production always
      cover the consumer demand. At higher wind speeds, where the wind production covers all of the
      consumer demand, the diesel engine will be clutched out and stopped completely. The innovative by
      Vestesen's WD-equipment is that the diesel engine in a large number of hours can be stopped completely
      and in this way considerable fuel savings can be obtained. See more about wind-diesel here.
  • wind penetration
    • The percentage of the yearly wind production in proportion to the yearly power demand. Information about
      high wind penetration.
  • WTG
    • Wind Turbine Generator

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