power grid terms

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power grid terms[edit]

See a more technical version of this same glossary of terms. The following is meant to be understood by non-power-geeks. See also this commercial blurb.

energy master planning[edit]

demand side management (DSM)[edit]

Any plan or system for reducing overall power use and timing so as to minimize peak loads and ultimately reduce all loads. Almost always involves diurnal (overnight) power storage and backup and must necessarily include energy conservation measures such as appliance replacement, insulation, lighting changes.

"Demand Response: Electric power generation and distribution systems are strongly affected by supply-side policies (how, when, and where to generate electricity, how to couple generation into the grid, how to transmit and distribute generated electricity) and demand-side policies (pricing schemes, conservation efforts, customer premises automation, and, in extreme circumstances, rolling blackouts). Demand-side programs focus on reducing the peak-to-average demand profiles through automation in the customer premises.

Demand Response or Demand Side Management can be achieved through demand reduction, by shifting load to a less expensive time period, or by substituting another resource for delivered electricity (such as natural gas or onsite power generation, also known as "distributed generation."

Demand Response (DR) is a set of activities to reduce or shift electricity use to improve electric grid reliability, manage electricity costs, and ensure that customers receive signals that encourage load reduction during times when the electric grid is near its capacity. The two main drivers for widespread demand responsiveness are the prevention of future electricity crises and the reduction of electricity prices. Additional goals for price responsiveness include equity through cost of service pricing, and customer control of electricity usage and bills. The technology developed and evaluated in this report could be used to support numerous forms of DR programs and tariffs." - demandsidemanagement.com

demand response[edit]

Demand response is the real-time aspect of demand side management: Signals sent to users' devices to tell them to shut down or off so as to deal with a grid peak event and avoid expensive time of use pricing for peak power. In most cases devices that comply generate revenue for the users.

demand response program[edit]

Any service, human or automated or combined, which helps users manage demand and rewards them for it (or relieves the pain of not doing it). Utilities implement demand response programs prior to time of use pricing to avoid smart meter backlash, political blowback, protests and sabotage: Unless users have opportunities to monitor and manage their demand before they are presented with huge bills for peak power, they revolt.

"Demand Response Programs are programs usually designed and offered by electric utilities that offers those clients that sign-up for specific DR programs with financial incentives and other benefits that help those participating customers to curtail energy use. These actions by the electric utilities and participating clients provide a reliable, predictable amount of power (megawatts) that the ISO's and RTO's can count on during an emergency when energy supplies are low, and there is an inadequate amount of available power generation. The electric utilities typically require that those customers that enroll in their DR program(s) install certain software and hardware, that communicates with these client's online energy management systems, and can control these client's electric power requirements as needed." - demandsidemanagement.com

technologies used in DSM[edit]

"These energy conservation technologies are implemented to reduce total energy use. Specific technologies include energy-efficient lighting, appliances, and building equipment, all of which can be found on the EREN Buildings Energy Efficiency page. For energy efficiency at industrial sites, see the EREN Industrial Energy Efficiency page. " - demandsidemanagement.com

load levelling[edit]

"These technologies are used to smooth out the peaks and dips in energy demand — by reducing consumption at peak times ("peak shaving"), increasing it during off-peak times ("valley filling"), or shifting the load from peak to off-peak periods — to maximize use of efficient baseload generation and reduce the need for spinning reserves. " - demandsidemanagement.com

load control / EMCS[edit]

"Energy management control systems (EMCSs) can be used to switch electrical equipment on or off for load leveling purposes. Some EMCSs enable direct off-site control (by the utility) of user equipment. Typically applied to heating, cooling, ventilation, and lighting loads, EMCSs can also be used to invoke on-site generators, thereby reducing peak demand for grid electricity. Energy storage devices located on the customer's side of the meter can be used to shift the timing of energy consumption." - demandsidemanagement.com

You couldn't pay me to igorne these posts!

More posts of this quality. Not the usual c***, palese


Any means of generating electricity. A generation strategy is never as efficient as a conservation strategy and rarely as efficient as a storage strategy and is never a good idea to implement first. However, because generation is generally more centralized and amenable to power politics it is often profitable for corporations and governments to focus on it. This is always a bad idea and inevitably results in extreme waste. Promoting generation over conservation and storage strategies will always favour fossil fuels and nuclear power, as advocates of these dirty fuels can compare the watt for watt price of generation to renewable generation (which they often win especially given the uncertain numbers) rather than to conservation (which they always lose and always will).

"renewable generation" advocates[edit]

Renewables advocates who promote generation over conservation sabotage any effort to reform a power system and are generally disregarded and disdained by experts. They discredit groups they speak for and are usually seen as shills for an industry (such as wind power) that is seeking government subsidies.


Cogeneration is any system where users can generate power that they contribute to the power grid and for which they receive a credit or payment. Usually implemented to relieve peak loads, a cogeneration system requires inverter, intertie and generation devices and also often power storage or power reservoir devices. It is always more expensive to implement cogeneration than simple peak levelling, storage, demand reduction or conservation/demand management systems, and should generally be done after all those measures are fully exhausted.

renewable generation[edit]

Any system of generation that does not rely on a non-renewable fuel (uranium, coal, oil). This is not the same as not generating pollution: Wood is a renewable fuel but very often when it is burned (especially in poorly adjusted fireplaces or stoves) it generates far more pollution than do fossil fuels.

While renewable generation can be off-grid it is almost always a better idea to feed power to the grid via interties and participate in [[demand response]. This avoids expensive and potentially dangerous storage technologies such as batteries, wasteful conversion of DC to AC power via inverters, and lets others rely on excess power generated by the renewable facility.


Power distribution is usually defined as the medium voltage lines that evenly distribute power throughout a neighbourhood or community.

district utility / distributor[edit]

A district utility or distributor is the organization that bills the customer and takes care of their service issues and complaints. District utilities in the smart grid era will support openADR providers, authenticated, bonded, secure security, safety and medical monitoring services, increasingly act as and compete with Internet service providers, telcos, cablecos and cellcos (often offering so-called triple play or quadruple play service which combines phone, cell, net and TV services).


Power transmission is usually defined as the very high voltage lines that move generated electricity from generators to end user distribution networks and district utilities. An open access transmission tariff guarantees that the highest bidder gets access to the lines without inhibition from any existing monopolies.

supply-side management[edit]

supply shortage[edit]

A supply shortage is any situation where a utility must buy poiwer. Volatility and shortages may be controlled either by supply-side management or by having sufficient supply availability to meet with rising demand or by Demand-Side Management (DSM) by curtailing electricity demand during supply shortages. For short term measures SSM is not effective as it takes long time for units to start up (if these are available) and meet the rising demand immediately, rather it is demand side management which can be implemented immediately and in more economic ways to keep the balance.

smart meter[edit]

load response program (LRP)[edit]

LRP are the actions undertaken in response to electricity supply position and wholesale market price of electricity. Or in other sense these refer to switching off or reschedule of non-essential and non-critical loads by the end users in response to the request of IMO or the utilities. This can lead to save the system network from exceeding its peak rating.

There are a large variety of load equipments and applications that can be switched on or off at a particular times to reduce electricity demand from the network.

Reliability-based programs:[edit]

These programs operate in response to the system contingencies. That is why these can also be called as “contingency” programs. These are used whenever there is an emergency of power supply in case of acute shortage due to less generation or more demand or due to some other system constraints. These programs are also called Emergency Demand Response Program (EDRP)

Market/Price based programs:[edit]

These programs are based on market price signals of electricity. This category includes programs that use time-of-use (TOU) rates/Real Time Prices, Interruptible Rates and Two-part Tariff. These rates are intended to reduce consumer bills through the application of time-differentiated rates. The consumer participants of these programs that curtail their loads at critical times of very high prices can also be paid some extra financial incentive to help maintain system reliability.

These programs can include Day Ahead Demand Response Program, where the end users respond to price signals and reduce loads when the price exceeds their set Base Price on day to day or day-ahead time basis.

IMO based Programs vs. Utility/Supplier Based Programs: Direct Load Control by IMO/Utility Operator and Load Control by Consumer. Implementing these technologies and techniques is not always so cheap. Though there are many opportunities where we can apply these without any additional cost or investment. But to apply them at large scale for the whole market there are various factors to be considered as:

   *Cost to the customer to shed and reschedule the load
   *Time it takes to activate the load response
   *The variation in wholesale price
   *Losses to occur in case of reliability problems due to acute shortage
   *Any losses in production by implementing these programs

Normally these programs are internet/web based. Different packages provide different services to the consumers. In some internet based programs the participants are alerted on real-time and day ahead prices. The customer can access the web site, check the prices and give their price option and the load to be curtailed. The supplier give notification to the customer by e-mail, cell phone, pager, or fax about the curtailment.

OPG IEEP[edit]

Similarly the Internal Energy Efficiency Program of Ontario Power Generation (OPG) in Canada since 1994 has helped to save 2,131 GWh of energy every year, 2.4 million metric tonnes of emission savings for CO2, NOx and SO2 and a saving of US$85.2 million every year.

DSM benefits[edit]

"Demand Side Management programs play an important role in mitigating electrical system emergencies, avoiding blackouts and increasing system reliability, reducing dependency on expensive imports, reducing high energy prices, providing relief to the power grid and generation plants, avoiding high investments in generation, transmission and distribution network and leading to environmental protection.

Thus it provides significant economic, system reliability and environmental benefits.

DSM techniques are the cheapest, fastest and cleanest way to solve our electricity problems. These can be immediately implemented and many times at one-tenth the cost of building new power plants.

This is what needed at this moment in Ontario when it is passing through the phase of uncertainty, already partially backed out from its deregulation policies by placing price caps or regulating prices. Forecast about power shortage in Ontario in the coming years, aging existing power plants with less investments in new generation compel us to go for the only option left i.e. controlling demand through Demand Side Management to avoid blackouts and power imports at high prices." - demandsidemanagement.com

actual peak reduction[edit]

"Actual Peak Reduction - The actual reduction in annual peak load (measured in kilowatts) achieved by consumers that participate in a utility DSM program. It reflects the changes in the demand for electricity resulting from a utility DSM program that is in effect at the same time the utility experiences its annual peak load, as opposed to the installed peak load reduction capability (i.e., Potential Peak Reduction). It should account for the regular cycling of energy efficient units during the period of annual peak load. " - demandsidemanagement.com

annual effects[edit]

"Annual Effects - The total changes in energy use (measured in megawatthours) and peak load (measured in kilowatts) caused by all participants in your DSM programs. This includes new and existing participants in existing programs (those implemented in prior years that are in place during the given year), all participants in new programs (those implemented during the given year), and participants in DSM programs that were terminated after 1992. Please note that Annual Effects are not a summation of 12 monthly peaks or the aggregate of the Incremental Effects for the reporting year, but are the total effects of all DSM programs for all participants (new and existing) for the year." - demandsidemanagement.com


direct load control[edit]

"Direct Load Control - DSM program activities that can interrupt consumer load at the time of annual peak load by direct control of the utility system operator by interrupting power supply to individual appliances or equipment on consumer premises. This type of control usually involves residential consumers. Direct Load Control as defined here excludes Interruptible Load and Other Load Management effects. " - demandsidemanagement.com

energy effects[edit]

"Energy Effects - The changes in aggregate electricity use (measured in megawatthours) for consumers that participate in a utility DSM program. Energy Effects represent changes at the consumer's meter (i.e., exclude transmission and distribution effects) and reflect only activities that are undertaken specifically in response to utility-administered programs, including those activities implemented by third parties under contract to the utility. To the extent possible, Energy Effects should exclude non-program related effects such as changes in energy usage attributable to nonparticipants, government-mandated energy-efficiency standards that legislate improvements in building and appliance energy usage, changes in consumer behavior that result in greater energy use after initiation in a DSM program, the natural operations of the marketplace, and weather and business-cycle adjustments. " - demandsidemanagement.com

energy efficiency[edit]

"Energy Efficiency - DSM programs that are aimed at reducing the energy used by specific end- use devices and systems, typically without affecting the services provided. These programs reduce overall electricity consumption (reported in megawatthours), often without explicit consideration for the timing of program-induced savings. Such savings are generally achieved by substituting technologically more advanced equipment to produce the same level of end-use services (e.g., lighting, heating, motor drive) with less electricity. Examples include energy saving appliances and lighting programs, high-efficiency heating, ventilating and air conditioning (HVAC) systems or control modifications, efficient building design, advanced electric motor drives, and heat recovery systems. " - demandsidemanagement.com

energy conservation measure[edit]

There are various opportunities and techniques available for reducing energy consumption such as efficient lighting, variable speed drives, solar hot water systems etc. These technologies reduce demand, help in lowering high peak prices and also reduce greenhouse gas emissions due to less stress on generating plants.

incremental effect[edit]

"Incremental Effects - The annual changes in energy use (measured in megawatthours) and peak load (measured in kilowatts) caused by new participants in existing DSM programs and all participants in new DSM programs during a given year. Reported Incremental Effects are annualized to indicate the program effects that would have occurred had these participants been initiated into the program on January 1 of the given year. Incremental effects are not simply the Annual Effects of a given year minus the Annual Effects of the prior year, since these net effects would fail to account for program attrition, equipment degradation, building demolition, and participant dropouts. Please note that Incremental Effects are not a monthly disaggregate of the Annual Effects, but are the total year's effects of only the new participants and programs for that year. " - demandsidemanagement.com

interruptible load[edit]

"Interruptible Load - DSM program activities that, in accordance with contractual arrangements, can interrupt consumer load at times of seasonal peak load by direct control of the utility system operator or by action of the consumer at the direct request of the system operator. This type of control usually involves commercial and industrial consumers. In some instances, the load reduction may be affected by direct action of the system operator (remote tripping) after notice to the consumer in accordance with contractual provisions." - demandsidemanagement.com

load shape[edit]

"Load Shape - a method of describing peak load demand and the relationship of power supplied to the time of occurrence." - demandsidemanagement.com

load management[edit]

"Other Load Management - DSM programs other than Direct Load Control and Interruptible Load that limit or shift peak load from on-peak to off-peak time periods. It includes technologies that primarily shift all or part of a load from one time-of-day to another and secondarily may have an impact on energy consumption. Examples include space heating and water heating storage systems, cool storage systems, and load limiting devices in energy management systems. This category also includes programs that aggressively promote time-of-use (TOU) rates and other innovative rates such as real time pricing. These rates are intended to reduce consumer bills and shift hours of operation of equipment from on-peak to off-peak periods through the application of time-differentiated rates. " - demandsidemanagement.com

potential peak reduction[edit]

"Potential Peak Reduction - The potential annual peak load reduction (measured in kilowatts) that can be deployed from Direct Load Control, Interruptible Load, Other Load Management, and Other DSM Program activities. (Please note that Energy Efficiency and Load Building are not included in Potential Peak Reduction.) It represents the load that can be reduced either by the direct control of the utility system operator or by the consumer in response to a utility request to curtail load. It reflects the installed load reduction capability, as opposed to the Actual Peak Reduction achieved by participants, during the time of annual system peak load." - demandsidemanagement.com

utility program cost[edit]

"Program Cost - Utility costs that reflect the total cash expenditures for the year, reported in nominal dollars, that flowed out to support DSM programs. They are reported in the year they are incurred, regardless of when the actual effects occur." - demandsidemanagement.com

"peak load" (US statistics)[edit]

In 1997, 971 electric utilities reported having DSM programs. Of these, 561 are classified as large and 410 are classified as small utilities. The 561 large utilities account for 89.5 percent of the total retail sales of electricity in the United States.(1)

Energy savings for the 561 large electric utilities decreased to 56,406 million kilowatthours (kWh), 5,436 million kWh less than in 1996. These energy savings represent 1.8 percent of annual electric sales of 3,140 billion kWh to ultimate consumers in 1997.

Actual peak load reductions, the goal of the DSM program, for large utilities was 15.4 percent lower in 1997, at 25,284 megawatts, than in 1996. Potential peak load reductions were 14.7 percent lower in 1997 than in 1996.

large vs. small utility[edit]

Large utilities are those reporting sales to ultimate consumers or sales for resale greater than or equal to 120,000 megawatthours. Small utilities with sales to ultimate consumers and sales for resale of less than 120,000 megawatthours are only required to report incremental energy savings and peak load reduction, and total utility and total DSM costs for the reporting year and for the first forecast year.

supply-side investment[edit]

It is tempting, but misleading, to compare DSM costs to supply-side investments on an unadjusted cost-per-kilowatthours or cost-per-kilowatt basis. The calculation of appropriate measures for economic comparisons of DSM and supply-side investments requires that consideration of the life-cycle cost of the options being compared be addressed on an integrated basis (i.e., the interaction of the change in end-use patterns with the production function of the utility must be considered over the expected life of the various options being compared). In addition, the rate impacts of each alternative must be compared because alternative DSM/supply-side combinations may result in differing patterns of revenue requirements over time. The data presented are not sufficient to allow for such comparison.