SOLAR TODAY
APRIL 2009
VOL. 23, No. 3
Long the ruin of sustainable community efforts, the
energy-hogging transport sector finally has a viable green
option in the coming fleet of electric-drive vehicles.
By TERRY PENNEY and HOWARD BROWN
microalgal oil would improve the energy balance considerably, but any significant market
share for such technology is years away.
But now, a coming fleet of mass-produced,
plug-in electric-drive vehicles promises an alternative. Deployed within a “smart electric grid”
capable of supporting information exchanges among utilities, businesses and homeowners, plug-in hybrids offer the opportunity
for truly sustainable communities nationwide.
Little more than a vision a few years ago when
SOLAR TODAY published “Plugging In to
Renewable Communities” (Penney and Elling,
May/June 2006), the sustainable community
is edging toward reality as the supporting elements near fruition.
plants, widespread use of PHEVs will likely
reduce both toxic and carbon air emissions.
In a bold move directly supporting sustainable communities, General Motors in February outlined a roadmap for cities to become
“plug-in ready.” Suggested measures include
“public and workplace charging infrastructure;
consumer-friendly electricity rates and renewable electricity options; government and corporate vehicle purchases; supportive permitting and codes for vehicle charging; and other
incentives” (press release at media.gm.com).
Federal regulators have also signaled support.
Jon Wellinghoff, the Federal Energy Regulatory Commission’s new chair, in late January
told the utility and automobile industries that
they must integrate electric vehicles into the
national power grid.
Terry Penney is a principal laboratory program
manager for advanced vehicle and fuels
technologies at the National Renewable Energy
Laboratory, having worked in the renewable
energy field for 30 years. Prior to NREL, he
worked on the design and testing of NASA’s
space shuttle. Howard Brown is a science writer
for NREL. His previous work includes policy
analysis for the U.S. Congress and the state of
Colorado and river preservation advocacy.
Becoming Plug-In Ready
A Chevy Volt extended-range electric vehicle (EREV), a straight-electric vehicle (EV) Aligning the Electric Grid
Ford Transit light-duty van and a Toyota Prius A second key development is the availability
plug-in hybrid (PHEV) could be here as soon of “smart grid” technology. Smart grid electri-as 2010, and many other EVs and PHEVs are cal distribution networks convey information
in the works. (With an EREV, an electric motor as well as power, so utilities, businesses and
drives the vehicle, while a small engine acts as a homeowners can better manage their electric-generator to recharge the batteries as needed. ity use, and air conditioners, plugged-in vehi-In a PHEV, both a motor and an engine are cles or other power applications can be cycled
used either in parallel or in series to drive the on and off to manage peak electrical demands.
vehicle.) Indeed, nearly every major auto man- Smart grid systems will also enable power to be
ufacturer plans to have an EV on the market by drawn from plug-in batteries to help improve
2012. (See a detailed listing by maker, type and electric power quality, meet peak demands or
status at solartoday.org/plugin.) provide emergency power during an outage.
Shifting to plug-in electric drive could be Smart grid technology is thus a tremendous
the biggest change the automobile industry has door opener for realizing the full potential of
seen in 100 years — since, ironically, Henry plug-in electric vehicles. Leadingorganizations,
Ford and Thomas Edison were debating the including Rocky Mountain Institute (see “
Get-merits of gas- over electric-powered vehicles. ting to Transportation’s Fourth Shift,” page
PHEVs are, of course, only as sustainable as the 22), are advocating for smart grid applications
electricity with which they are charged, but in to support electric transportation. The Electric
the context of a sustainable community, they Power Research Institute, as another example,
dramatically enhance our ability to live sus- is promoting an “ElectriNet” that would com-tainably. Analyses by the National Renewable bine low-carbon generation, smart grids, local
Energy Laboratory (NREL) and others find energy networks and electric transportation.
that even if powered by conventional electric Already, progressive cities are pursuing
smart grid applications. University of Delaware
Professor Willett Kempton recently forged a
project among the university; Newark, the city
in which UD is based; and the state of Delaware to develop a vehicle-to-grid (V2G) system in Newark. Boulder, Colo., is also working
to incorporate PHEVs and V2G benefits. Here,
electric utility Xcel Energy is installing fiber-optically connected monitoring equipment
for transformers and other grid components
and smart meters for homes within its distribution system to develop a SmartGridCity. The
systems will tell consumers which appliances
are drawing the most power and enable users
to turn them on or off from a remote computer.
Boulderites will also be able to plug in electric-drive vehicles to charge when rates are low or
to feed power back to the grid during peak
power periods. The Boulder system takes
advantage of technology from GridPoint Inc.
( gridpoint.com), which markets a software
platform that monitors and controls electrical
