Hydrogen

Plug-in Hybrid Electric Vehicles

PHEV technology provides an evolutionary path to some of the most important advances in energy technology of the 21^st century. Aspects of this technology include:

· Why PHEV is so Important 1

· The Hydrogen Economy Dream.. 1

· Very Real, but Different, Dream.. 3

· More Than Displacing Vehicle Emissions. 3

· Newest Addition to PHEV Family. 3

Why PHEV is so Important

Based on traveling 18,000 miles per year, the average yearly gasoline consumption for conventional, HEV, and PHEV vehicles are the following:

Conventional Vehicle	600 gallons
HEV	400
PHEV	80

This is why PHEV technology is so important to the U.S.—PHEV technology substantially eliminates the use of petroleum as a fuel. Instead of petroleum, electricity is used, and this electricity can be provided by a variety of sources including wind power, solar energy, coal, or nuclear. PHEV technology delivers these benefits while saving consumers money.

But the benefits do not end with the ability of PHEV technology to substantially eliminate the use of petroleum in passenger cars.

About half the gasoline consumed in the U.S. is consumed in the first 20 miles of daily travel of an automobile, and so, even 20 miles of plug-in range can have a dramatic impact on the national economy. To use mostly plug-in grid power at 12,000 miles per year would require 34 miles of plug-in range, and so, a PHEV-30 to PHEV-60 would best serve the needs of a typical American consumer.

The Hydrogen Economy Dream

PHEV technology will evolve into the hydrogen economy dream. The stages of evolution include commercialization of the following technologies:

Stage 1: HEV Technology

Stage 2: PHEV Technology Using Batteries

Stage 3: PHEV Technology Using Batteries and Regenerative Fuel Cells

Stage 4a: PHEV Technology Using Mostly Regenerative Fuel Cells

Stage 4b: City Car Limited-Range HHEV without Engine Backup.

Stage 5: PFCHEV Technology with Cheap Engine

Stage 6: PFCHEV Technology Using Duel-Fuel Fuel Cells that Eliminate Need for Engine

Stage 1 has already started with close to a dozen different versions of HEVs commercially available.

Stage 2 has already been initiated with Renault’s Kangoo. A PHEV version of the Mercedes-Benz Sprinter was on display at the Hanover IAA Commercial Vehicle Show 2004 (see Newest Addition to PHEV Family 3).

Stage 3 is the seed that will grow into the hydrogen economy and is already economically competitive, but the concept has yet to leave the drawing boards. By using a 0.8 kW regenerative fuel cell (RFC) stacks as battery chargers in PHEVs, the plug-in range can be doubled for the typical application. For example, to attain 20 miles of plug-in range, a vehicle would have a 10-mile battery pack and a 10-mile RFC system. The 10-mile battery pack gets the driver to work. While at work, the 10-mile RFC system recharges the battery pack so the battery pack can take the driver home after an eight-hour work day. The RFC system uses grid electricity to convert water to hydrogen and oxygen during the night, and during the day, the RFC system uses the stored hydrogen and oxygen to recharge the battery. The RFC-Battery combination is less expensive than batteries or RFCs alone.

The RFC uses hydrogen as a fuel—it is the culmination of the hydrogen economy.

Stage 4.represents the transition to a mostly RFC-based automobile. While projecting fuel cell prices and respective costs for PFCEV systems, this will be economically viable in about 2013 for the PFCHEV-60. Since the price of fuel cells continues to rapidly decrease, in 2013 a 15 kW RFC system will cost about $4,900 as compared to about $6,000 for the battery pack required for a 60-mile plug-in range. It will be about 2015 before the PFCHEV-60 displaces the PFCHEV-40 and about 2017 before the PFCHEV-60 displaces the PFCHEV-20. For the “mostly RFC-based automobile”, there is little economic penalty in going from 20 to 60 miles of plug-in range, and so—this is why “-20” and “-40” models will eventually be replaced by models with higher plug-in ranges.

Stage 5.includes increasing ranges for the PFCHEV vehicles—form PFCHEV-60 to PFCHEV-120 or even PFCHEV-200. With these ranges, the engine would rarely be used and expensive/efficient engines could be replaced with cheap/inefficient engines will little impact on average fuel economy. The advantage is that the initial cost of the vehicle would be reduced by $500 to $1,000.

Stage 6 includes eliminating the use of petroleum-based fuels in automobiles and can be based on fully renewable, fully sustainable, and fully indigenous energy sources. Today most versions of low-temperature fuel cells are powered from hydrogen; however, modified fuel cells are able to run from methanol. As methanol (or ethanol) fuel cell technology is improved, it will be viable to produce fuel cells that can be fueled by either hydrogen or methanol. (This is actually possible today, but debatably, a fuel cell optimized for use with methanol is not best used with hydrogen as a fuel.) It will be possible to have vehicles where 80%-90% of the miles are from plug-in hydrogen with the remaining 10%-20% from methanol (or ethanol) that can be refueled similar to gasoline.

Very Real, but Different, Dream

PHEV technology evolves into a hydrogen economy where the RFC system produces hydrogen onboard the vehicle during the night and uses that hydrogen during the day. The consumer never has to handle hydrogen, and no hydrogen refueling infrastructure is required. For longer trips, renewable and indigenous ethanol can be used to refuel the vehicles and provide extended ranges.

While PHEV vehicles do not require advances in hydrogen storage, hydrogen refueling, and/or hydrogen production by systems (other than RFC systems on the vehicles), the PHEVs will create a market for all these technologies much quicker and much greater than other approaches. PHEVs can be designed that allow refueling with hydrogen if there are regional desires to refuel with hydrogen..

More Than Eliminating Oil Imports

More Than Displacing Vehicle Emissions

The benefits of PHEV technology extends beyond eliminating oil imports and displacing vehicle emissions from our cities. By using off-peak electricity, base load electricity demands are increased that will ultimately lead to substantial increases in the average efficiency with which electrical power is produced. In addition, electrical power can readily be produced from non-greenhouse gas emission sources like wind power and nuclear power—this technology is bring a halt to increasing greenhouse gas emission problems and the resultant global warming. Additional details can be found at Benefits.

Newest Addition to PHEV Family

Daimler Chrysler is introducing the newest addition to the PHEV family. The news release can be found at Sprinter with detailed excerpts as follows:

Diesel engine combined with electric engine: Mercedes-Benz Sprinter now also with hybrid drive

Quiet, emission-free operation around town

Fuel consumption reduced by between 10% and 50%

Two versions: Plug-in hybrid drive and hybrid drive

Plug-in version on display at Hanover IAA Commercial Vehicle Show 2004

Stuttgart, Jul 30, 2004

For many decades, Mercedes-Benz has also been a pioneer in the exploration of environment-friendly, resource-friendly propulsion systems. Whether in natural gas, LPG, electric propulsion or the particularly future-oriented fuel cell, Mercedes-Benz is a leading developer. This pioneering position will be highlighted once again at the IAA Commercial Vehicle Show 2004, this time with a plug-in hybrid-drive Sprinter. Plug-in means that the vehicle is equipped with a power socket which enables the batteries to be recharged even when the engine is not running, for example overnight. A hybrid-drive Sprinter with no recharging socket is also planned.

In the hybrid-drive Sprinter (with or without a recharging socket) an electric motor is integrated into the drive train between the transmission and clutch. It obtains its energy from a nickel/metal hydride battery which it constantly recharges when on the move, acting as a generator and using the energy produced when braking or on downhill gradients (recuperation). The basic vehicle is a Sprinter 311 CDI (3.5 t GVW, kerb weight 1960 kg) with an automatic transmission.

A hybrid-drive van can provide zero-emission, exceptionally quiet operation when travelling in towns and other emissions-sensitive areas. Other advantages include an unrestricted operating range thanks to the internal com-bustion engine, familiar operation which is largely the same as for a conventional vehicle and a high level of operating safety. Last not least, the operator is rewarded with a reduction in diesel fuel consumption of between 10% and 50% depending on the type of operation.

Plug-in hybrid drive with a 70 kW electric motor

Since the two drive units – the internal combustion engine and the electric motor - are intelligently configured in parallel, the hybrid Sprinter can be optimally operated to suit the situation: emission-free, low-noise operation in sensitive areas (city, warehouses) under pure electrical power and fuel-reducing hybrid operation by supporting the internal combustion engine with electrical power at low speeds and when accelerating. When the accelerator is fully depressed for maximum performance, both power units operate together. This so-called boost function is appropriate when more performance is required for acceleration or on uphill gradients. During normal operation the driver is able to select the required drive unit at the push of a button.

In the plug-in hybrid drive system in the Mercedes-Benz Sprinter, an elec-tric motor with an output of 70 kW is combined with the conventional diesel engine. It obtains its energy from a nickel/metal hydride (NiMH) battery with a capacity of 14 kWh. This allows an operating range of up to 30 kilometres under purely electric propulsion. The battery is recharged from the mains power supply, e.g. overnight, with a recharging time of approx. six hours. The energy generated when braking is also used to recharge the battery.

Workmen, disaster relief organisations or the fire services can also use the 40 kW electric motor in the Sprinter with plug-in hybrid drive as a generator to operate tools and machinery while in the field. The additional electrical equipment weighs 350 kg. If lithiumion batteries are used in place of the NiMH batteries, the weight penalty is reduced to 160 kg.