Hydrogen-Boosted Gasoline Engine Overview
Faced with the ever-increasing cost of gasoline, automakers worldwide are working overtime to cost-effectively improve vehicle fuel economy while still meeting today's strict emissions requirements. One promising way to boost fuel economy is to add hydrogen to the fuel/air mixture in a conventional gasoline engine. It's called a hydrogen-boosted gas engine. However, since hydrogen isn't readily available at your local filling station, selling a hydrogen-boosted gas engine hasn't been on any automakers' short list. Until now, that is.
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In this article, we'll explain a new technology that utilizes a fast-response on-board reformer to generate a small amount of hydrogen from gasoline. This hydrogen is added to the engine's normal air/fuel mixture. Engines designed to run on a mix of hydrogen/gasoline can see a fuel-economy gain of 20 to 30 percent with no requirement for control of harmful NOx emissions, oxides of nitrogen. On the next two pages, we'll tell you how this new fuel-saving engine works and why it looks like it has the potential to become a viable, fuel-saving technology. We'll address the following issues regarding this new technology:
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What Is a Hydrogen-Boosted Gasoline Engine?
A small amount of hydrogen made on-board by the reformer is added to the normal
intake air and gasoline mixture in the vehicle's engine. This greatly improves
overall combustion quality by allowing nearly twice as much air for a given
amount of fuel introduced into the combustion chamber. This is more energy
efficient because it saves energy by reducing the amount of engine pumping
needed. Learn what the experts are saying about this new technology.
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The Future of Hydrogen-Boosted Gas Engines
The
race is on for the fuel-economy leadership position. Where will the
hydrogen-boosted gas engine fit in with other fuel-saving technologies like
hybrid cars, E85 ethanol-powered vehicles, and new clean diesel-powered cars.
How much gas does it save compared to other alternative fuel-powered vehicles?
Will consumers begin seeing this type of engine in cars in the near future? Find
out in this section.
The Future of Hydrogen-Boosted Gas Engines
Hydrogen-boosted gasoline engines have the potential to considerably improve fuel economy. A major cost and environmental advantage of the hydrogen-boosted lean system engine are low amounts of NOx emissions gasses, hence, complete elimination of the need for external NOx emissions control. Currently, NOx emissions control is a major cost problem for diesels which use expensive traps to meet emissions standards. Diesel particulate emissions must also be collected by a filter that must be periodically regenerated.
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Hydrogen-boosted gasoline engines require neither NOx or particulate control
filters and require only a low cost oxidation catalyst to control small amounts
of exhaust (unburned hydrocarbons) formed mostly during engine start-up and
early warm up. Additional cuts in emissions control requirements stem from the
engine's ability to use only the clean hydrogen enriched charge during the cold
start phase when 90% of emissions are generated in the emissions test.
The hydrogen-boost system is effectively a bolt-on technology that can be added
to an existing vehicle's engine compartment. According to the developers, the
cost of the system is less than half of the added cost for diesels. U.S. auto
industry production costs for tooling diesels to replace gasoline engines are
enormous and would be difficult for U.S. makers currently struggling with
financial difficulties.
A prototype hydrogen-boosted engine is now being installed in a V6-equipped SUV
that has sufficient free space for the reformer and its related system. The
start of long-term road testing for performance, reliability, and durability
information is planned for later this year with the first production application
marketing expected for 2010.
Performance data generated during the early phase of testing is certain to be
watched intensely by virtually everyone concerned with automotive and energy
environmental matters in part because the system is associated with the buzzword
"hydrogen."
High on the list of interested parties are makers of the large SUVs and vans for
which government regulators are seeking 10 percent higher average miles per
gallon vs. the 2007 level of 22.2 mpg. The new level of 24.1 mpg is to be
adhered to by 2011.
Four-cylinder vehicles will likely also be prime candidates for the technology
as high gasoline prices continue to generate competition among the high fuel
economy models seeking mpg leadership. A contributing factor in the compact car
market may be a concern with hybrid vehicle lifetime cost due to system
complexity and battery replacement, reported in some cases to be as high as
$5000. This is just now beginning to be reflected in low resale values as early
production hybrids reach high mileage.
The hydrogen-boosted engine will not be alone, however, in the race for fuel
economy leadership position. Advanced turbocharged downsized direct injected
variable valve engines, common-rail diesel engines, hybrids, and flex-fuel
vehicles are all vying for the automaker's attention in the fuel-economy race.
None of these technologies can boast all of the advantages of the
hydrogen-boosted engine, namely dramatically increased fuel economy, minimal
emissions control, and overall cost-efficiency. In the end, it will take a
combination of many technologies to address this nation's thirst for driving
freedom, but it's likely that we'll hear a lot more about the hydrogen-boosted
engine in the future.
How Plug-In Hybrid Cars Work
Because
of their promise of improved fuel economy and reduced tailpipe emissions,
vehicles employing hybrid drivetrain technology have drawn the attention of both
the media and automotive consumers. There is no question that the technology
works, typically providing fuel economy gains of 25-40 percent when compared to
similar vehicles with conventional drivetrains.
Looking for ways to further improve fuel-economy, manufacturers are exploring
enhancements to the basic hybrid concept. One promising avenue is the plug-in
hybrid car. In simplest terms, plug-in hybrid cars incorporate traditional
hybrid technology but benefit additionally from plug-in charging.
While several manufacturers claim to be working on the technology, General
Motors' Saturn division has promised to introduce a plug-in hybrid version of
its Vue SUV by 2009.
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Expanding
further on plug-in hybrid technology are two vehicles still in the concept
stage. The Chevrolet Volt, which was introduced at the 2007 Detroit Auto Show,
and the Ford Edge with HySeries Drive, also introduced in 2007, combine elements
of plug-in charging with other potentially fuel-conserving technologies.
The following article will explain exactly how plug-in hybrid cars work. It also
will examine some of the benefits of plug-in hybrid cars.
Plug-in Hybrid Cars Explained
In summary, current hybrid vehicles have a gasoline engine that is assisted
by an electric motor, which helps it save gas. A typical hybrid vehicle
conserves fuel a few different ways. It recaptures energy lost through braking
and decelerating. This recaptured energy is stored in a battery pack as
electricity. As demand warrants, the stored electricity is used to power an
electric motor that assists the vehicle's gasoline engine--usually during
acceleration.
Many hybrid vehicles conserve additional fuel by incorporating a shut-off system
that shuts down the engine during stops. In these cars and trucks the electric
motor alone may propel the vehicle for short distances.
Hybrid vehicles available today are closed systems, and do not require plug-in
charging. A plug-in hybrid vehicle expands on the hybrid concept by allowing for
the battery pack to be even further recharged through plug-in charging.
According to Saturn, the Vue plug-in hybrid will use a conventional electric
cord that can be plugged into any 110-volt household wall outlet.
While a conventional hybrid vehicle may travel short distances in pure-electric
mode, plug-in hybrids are designed to travel extended distances with little or
no assistance from the gasoline engine. Even before the charge is depleted, the
gasoline engine may be called on to provide additional power for recharging the
battery, accelerating, passing, and merging.
While operating on the additional plug-in charge, a plug-in hybrid more-or-less
works the opposite of a conventional hybrid, with the electric motor acting as
the primary power source, and the gasoline engine providing supplemental
motivation. In the case of the Vue, once the initial charge is depleted, it
would operate just as conventional hybrid does, using the gas engine. The
Chevrolet Volt Concept is designed to use only its electric motor, using
gasoline only to aid in battery recharging, not driving.
To keep vehicle weight inline with a conventional hybrid, plug-in hybrids would
have little or no additional battery capacity. As such, the distance a plug-in
hybrid will travel in pure-electric mode will be relatively modest. Saturn has
suggested distances as great 40 miles, and as low as 20; GM estimates that the
Volt Concept could travel an average of 40 miles per charge.
In the next section, we'll detail the benefits of plug-in hybrid cars and take a
sneak peak at pure plug-in concepts from Chevrolet and Ford.
For more information about hybrid cars, go to:
· Hybrids come in many shapes and sizes. Read Consumer Guide's new-car reviews of all the latest Ford, Honda, Lexus, Saturn, and Toyota hybrid cars and trucks.
· The Chevrolet Volt Concept was unveiled at the 2007 Detroit Auto Show. Click here for more Volt pictures and information.
· Volt wasn't the only alternative fuel-powered concept car unveiled at the 2007 Detroit Auto Show. Read about other fuel-cell, biofuel, and electric-powered vehicles on the stage.
The Benefits of Plug-In Hybrid Cars
So, what are
the benefits of plug-in hybrid cars? Plug-in hybrid drivetrains may seem like a
complicated solution to a simple problem, but in reality they address the two
fundamental issues that have prevented pure electric vehicles from becoming
economically viable: range and weight.
Though battery technology has improved dramatically in recent years, the
potential range of a pure electric vehicle is still below the roughly 300-miles
of travel a typical consumer expects from a tank of gas.
According to Saturn, with a pure-electric range of up to 40 miles, the Vue
plug-in hybrid will accommodate the 80 percent of consumers who live within a
20-mile radius of where they work. For these drivers, the gasoline engine would
only be used to provide extra power for acceleration, passing, and merging.
Because the drivetrain is engineered for maximum efficiency in daily short-range
driving, a plug-in hybrid is not saddled with what Saturn estimates is 400-600
pounds of additional battery capacity.
Given that it should be possible to always drive a plug-in hybrid vehicle within
the range of its plug-in battery capacity, and gently enough to avoid requiring
power assistance from the engine, it is theoretically possible to never consume
gasoline.
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More
likely, fuel consumption would decrease dramatically in routine commuting,
though the reduced cost of gasoline is offset to some extent by increased
electricity usage.
Pure Plug-in Concepts:
The Chevrolet Volt Concept and Ford Edge with HySeries Drive
While Vue will be able to run on its gas engine after the battery's power is
exhausted, Volt Concept's motor will soley get its power from the electric
battery. This concept car is most notable for what it doesn't have than for what
it does. Not a hybrid in the conventional sense, the Volt's gasoline engine
never powers the vehicle's wheels. Instead, in the event that the car's plug-in
charge is depleted, a small gasoline engine is used to power a generator that
supplies back-up electricity. As the gasoline engine never provides power
directly to the drive wheels, Volt does not require a conventional transmission.
Relatively light and compact, Volt's three-cylinde