Glossary of Terms
What is the smart grid?
The smart grid marries information technology with our current electrical
infrastructure, helping us support the energy needs of our 21st Century
society. The smart grid is, in essence, an “energy Internet,” delivering
real-time energy information and knowledge—empowering smarter energy choices.
Considering the energy challenges we currently face, we must find a way
to do more with less—and quickly. This is the role for a smarter grid,
- Enables the integration and optimization of more renewable energy
(such as wind and solar) and plug-in electric vehicles.
- Drives significant increases in the efficiency of our network.
- Empowers consumers to manage their energy usage and save money without
compromising their lifestyle.
2. Are smart-grid technologies shovel ready?
Many smart grid technologies are "shovel ready". Here are just two examples.
- Advanced Metering Infrastructure (commonly referred to as AMI)
and smart meters, which serve as the foundation for consumers and
utilities to work together to maximize our current electrical resources
through information exchange and
- Grid management software and grid automation technologies that
can deliver significant increased energy efficiencies in our network
Most of what’s discussed in this site is ready for deployment
3. Will the smart grid stimulus funding
support job creation?
Funding deployment of existing Smart Grid technologies will
provide immediate job creation. In fact, the $16 billion targeting clean,
efficient American energy could create approximately 280,000 new jobs,
with 150,000 being created in the first year.
4. How will the stimulus funding be focused
on smart grid?
The promise of the smart grid is the societal benefits it will
deliver to our national energy security and carbon reduction initiatives.
To this end, we advocate focusing the stimulus spending on the technologies
that will deliver meaningful consumer and societal benefits. Smart grid
technology can help reduce our dependence on fossil fuels and lower our
CO2 emissions via the following four key deliverables:
- Delivery management - Increased grid efficiencies
through network intelligence: conserving finite natural resources,
lowering the cost of electricity, and reducing emissions.
- Demand management - empowering consumers with
information to manage usage and save up to 10% on power bills and
cut their power use 15% during peak hours.
- Renewable integration - reducing our nation’s
dependence on foreign oil by enabling the seamless integration of
cleaner, greener energy technologies into our power network
- Plug-in electric vehicle integration - with time-of-use
rates and billing mechanisms, utilities will be prepared to integrate
and optimize plug-in cars, which will help decrease our dependence
on foreign oil.
Smart grid can reduce our dependence on fossil fuels and lower our
CO2 emissions by:
- Embracing more renewables, such as wind, solar and biogas—both
central and distributed generation
- Increasing the efficiency of the delivery of electricity –
enabling us to do more, with less, thereby, maximizing the use of
our finite natural resources
- Empowering consumers and businesses to make smarter energy choices
by providing them with real-time information about their energy use
- Preparing the grid to integrate and optimize plug-in electric cars.
In order to achieve these initiatives, smart meters and advanced metering
infrastructure, as well as advanced grid management and automation technologies,
will need to be deployed.
The unfortunate reality is that today, utilities’ revenues are
based on the amount of electricity sold, putting the energy efficiencies
delivered through a smarter grid in direct conflict with utilities'
bottom line. Ultimately, policy will be needed to encourage and reward
utilities for driving efficiency and conservation.
8. Why are Internet Protocol and open standards
Internet Protocol is an open, standardized foundation for networking America's
next great infrastructure—the smart grid.
Open standards are the hallmark of modern American industry and commerce.
By spurring innovation through the adoption of open technology standards,
we have built remarkably interoperable foundations that drive our economy,
ranging from the familiar electricity socket to the transformative information
superhighway that is the Internet.
9. Will a smart grid make me give up control
as a consumer?
No. Smart grid is all about choice, and empowering consumers to make smarter
energy decisions. Utility programs involving applications in your home
will likely be optional and incentive-based.
10. How can I get a smart grid?
Glossary of Terms
Smarter grids will be deployed at different times by different utilities
across the nation and all over the world. While you can’t purchase
a “smart grid” for your home, you can reach out to your local
utility or public utility commission and tell them you are interested
in smart grid and how it can provide you with additional choice and control
over how you use and pay for electricity. You can also opt to make smarter
energy choices today – whether it’s purchasing ENERGY STAR®
appliances or changing to compact fluorescent light bulbs (CFLs).
1. American Recovery and Reinvestment Act
(and how it relates to smart grid)
On February 17, 2009, President Obama signed the American Recovery and
Reinvestment Act of 2009 into law. This economic recovery package represents
the largest effort to stimulate the economy in United States history.
This includes $4.5 billion for activities to modernize the electric grid.
2. Asset optimization
Asset optimization refers to maximizing asset performance and
reducing unexpected failures of primary equipment (i.e. transformers)
through alerts, detection, diagnosis, and prognosis. Asset-optimization
technologies help maximize asset performance and life for just a small
fraction of what it would cost to replace them altogether.
Automation is bringing “intelligence” to the grid,
much as Internet technology has brought intelligence to computers. It
allows for remote monitoring and control assets on the power grid.
Capacitors on the grid will ultimately help improve grid efficiency
by minimizing electrical losses. Technically, a capacitor is a passive
electronic component consisting of a pair of conductors separated by a
dielectric. They can be used to store charge in an electrical circuit.
A capacitor functions like a battery, but charges and discharges much
Current is the flow of electrons in an electrical conductor,
such as power lines or a power cord. The amount of movement of the electricity
is measured in amperes.
6. Demand response
In the electrical grid, demand response (DR) allows the management
of customer consumption of electricity in response to supply conditions.
For example, letting electricity customers opt into programs that reduce
their consumption at critical times, or in response to market prices.
Demand response is generally used to refer to mechanisms used to encourage
consumers to reduce demand, thereby reducing the peak or overall demand
7. Distributed generation
Currently, most generation of electricity is centralized and
electricity is sent one way – from utility to consumer. With a smart
grid, the generation of electricity can be distributed – such as
solar panels on rooftops. Energy can then enter the grid from many more
8. Distribution grid
The part of the electric grid that is dedicated to delivering
electric energy to end-users. After traveling through transmission lines
and distribution substations, electricity reaches the distribution grid,
where distribution lines deliver electricity to industrial, commercial
and residential electricity customers.
Today, the distribution grid operates with little automation and intelligence,
which will be required to manage distributed renewable generation, support
grid efficiency technologies, control the isolation and restoration of
outages, and more. Without intelligence, maintaining a reliable supply
of power to customers will become increasingly challenging.
9. Distribution management systems
A Distribution Management System (DMS) is a smart grid automation
technology that provides real-time information about the distribution
network and allows utilities to remotely control devices in the grid.
10. Economic dispatch
This is a method of determining the most efficient, low-cost,
and reliable operation of a power system by dispatching available electricity
generation resources to supply demand. The primary objective is to minimize
the cost of generation while honoring the constraints of the available
11. Electric Cars and Plug-In Electric
An electric car is just that—a vehicle that is powered
primarily by electricity rather than gasoline. The power is stored in
batteries that are recharged by plugging the car into an electrical outlet.
Some electric cars may also use a gasoline-burning engine to supplement
their range and allow the batteries to be recharged as the vehicle is
driven. Such a system results in a plug-in electric hybrid vehicle (PHEV).
12. Energy management systems
The Energy Management System acts as the central nervous system
for the transmission grid, giving utilities or independent system operators
the ability to control generation and aggregate, manage, and dispatch
power at the transmission level.
The process of producing electric energy by transforming other
forms of energy, whether it is the burning of fossil fuels or the wind
turning a wind turbine.
14. Grid congestion
Congestion is a condition that occurs when insufficient transfer
capacity is available in power lines to allow for scheduled transmission
Load is the amount of electric power delivered or required at
any specific point on the system. The electric power required comes from
the electricity-consuming equipment of the consumers.
16. Monitoring and diagnostics
Smart grid monitoring and diagnostics technologies help utilities
maximize asset performance and reduce unexpected failures of primary equipment
(i.e. transformers) through alerts, detection, diagnosis, and prognosis.
By monitoring different gas levels within the transformer, for example,
smart sensors will detect and report potential problems back to the utility
in real-time. The information sent to the utility can be stored and analyzed
by advanced software, helping predict and prevent potential transformer
failure before it happens.
17. Net metering
Under net metering, consumers who own renewable generation (such
as solar on rooftops) can receive retail credit for at least a portion
of the electricity they generate.
18. Peaking plants
Peaking plants are power plants that generally run only when
there is high demand, known as peak demand, for electricity. In the U.S.,
this often occurs in the late afternoon and early evening, especially
during the summer when air conditioning is required. The peak power load
generally occurs when people return home from work, start cooking dinner,
and turn up the air conditioning. The time that a peaking plant operates
may be many hours a day or as little as a few hours per year, depending
on the condition of the region's electrical grid.
19. Reactive load (VArs)
Along power lines, a combination of electrical losses takes
place due to the complexities of how power is currently delivered. These
losses take place due to something called reactive load, or VArs, and
also “resistive load”, which is more like friction and has
to do with the length of the line.
More technically, reactive load (VArs) establish and sustain the electric
and magnetic fields of alternating-current equipment. Reactive load must
be supplied to most types of magnetic equipment, such as motors and transformers.
Reactive load is provided by generators or equipment such as capacitors,
and it directly influences voltage. It is usually expressed as VAr (Volt
20. Renewable portfolio standards
Renewable portfolio standards are regulatory policies requiring
the increased production of renewable energy sources, such as wind, solar,
biomass, and geothermal energies.
21. Resistive load
Resistive load is electrical waste that is transformed into
heat or other energy. Unlike the losses due to reactive load, it cannot
be regained or mitigated. It can be compared to friction that the electricity
encounters as it moves across the lines.
Sensors, in this case, refer to smart equipment placed at key
locations on the power grid. They sense what is happening with the electric
load or with the assets on the grid and communicate this status back to
23. Smart appliances
Smart appliances can be programmed to operate when it is most
cost effective to do so based on time-of-use pricing signals from the
utility. For example, a smart refrigerator would only enable the defrost
cycle to occur when electricity prices are lowest, without compromising
a consumer's lifestyle.
24. Smart meters
Smart meters are among the fundamental building blocks of smart
grid deployments. They track and report energy usage by time of day, enabling
utilities to charge less for electricity used during off-peak hours. As
a result, consumers can choose to shift energy-intensive activities to
times when rates are lower to save on energy costs.
25. Time of use pricing
Most consumers don’t realize the cost of electricity varies based
on demand. Electricity is cheaper to produce during off-peak hours and
more expensive during peak hours when additional generation is needed.
Yet most residential electricity customers pay one set price — regardless
of the time of day. Smart meter technologies enable “time of use”
pricing in states where variable pricing rates are available, offering
lower prices during off-peak periods.
26. Transmission grid
Electric power transmission is the bulk transfer of electrical
power from a generation facility to a load or distribution substation
center, which then distributes power to the end user.
The difference is electrical potential between any two points
of an electrical circuit, expressed in volts. Voltage is analogous to
water pressure through a pipe.