The 100+ miles-per-gallon, plug-in hybrid Hummer

Raser Technologies have debuted a Hummer H3 converted into a plug-in series hybrid to co inside with the listing of Raser company stock on the New York Stock Exchange. With the aerodynamics of a house (Cd .43) and a curb weight of 4700 lb (2132 kg) in standard trim, the H3 hardly makes for the ideal vehicle to base a hybrid conversion on. Raser chose the Hummer on the logic that trucks and SUVs are/were the best-selling vehicles in America and can benefit the most from increased fuel economy and reduced emissions. The recent economic slump and fuel price volatility have led to the Hummer brand being put up for sale (with no takers) while SUV sales have stalled with many plants former SUV plants now closed.

The Plug in technology demonstrator has the original 5.3 Liter V8 14 mpg (17.l/100 km) removed and replaced with a much smaller 2.2-liter turbocharged four-cylinder EcoTech engine. Because this is a series hybrid there is no mechanical connection between the engine and the wheels, the EcoTech drives a 100-kilowatt generator only which charges three lithium ion battery packs of 30 kWh battery capacity which Raser say will give an electric mode of 40 miles. Although the engine capacity more than halved the addition of the battery packs, electric motor and generator raises the curb weight by over 20% to 5720 lb (2594 kg).

The standard Hummer four wheel drive automatic transmission and transfer case is retained but moved back in the chassis to accommodate a 200kw AC Induction motor bolted on where the petrol engine would normally connect. Mechanical losses through a 4WD transmission system are in the region of 40% and the use of an automatic transmission pretty much eliminates one of the main benefits of a hybrid, brake regeneration.

To explain briefly, because electric motors have 100% torque from zero rpm with a flat torque curve throughout their rev range they do not need a multi speed gearbox like a combustion engine. As a comparison, the Chevy Volt is a series hybrid where the combustion engine charges the battery and an electric motor provides the drive to the wheels but it has only a single speed reduction gear between the motor and the drive shafts. The reason this is done is the achieve maximum drivetrain efficiency. Each time power is transmitted through a pair of gears 10-15% of the energy is lost to heat. To achieve maximum range in an electric vehicle the fewer number of gears between the motor output shaft and the wheels the more energy efficient the vehicle is. In a 4WD system there are more gear that 2WD cars because of the transfer case gearing and you most certainly don't want to put an automatic gearbox in an EV as they are much less energy efficient than even a manual gearbox. On top of the huge power loss in the transmission the lack of regeneration just makes this hybrid conversion half baked.

While the Raser claims of 100MPG sounds impressive it is only achieved in electric only mode where energy consumption is usually measured in watt-hours / mile. As a comparison an electric vehicle like the Wrightspeed X1 consumes 200 wh/mi which they calculate is equivalent to 170 MPG. Although the X1 is a much lighter vehicle the 5 door Chevy Volt also gets approx 200 wh/mi.

Toyota's 2010 Prius breaks cover

The third-generation Toyota Prius 50 MPG hybrid features a more aerodynamic shape, larger 1.8 litre petrol engine with optional roof-mounted solar panels and intelligent park assist. Unfortunately the 2010 Prius is not yet a plug in hybrid and still comes with a relatively small Nickel-metal hydride battery so EV only mode will not exceed approx 5 miles. While the current model Prius is EPA rated at 46 mpg, the third-generation Prius has increased fuel economy to an estimated 50 miles per gallon for the new Prius. (It has not been EPA rated as yet)

90% new Drive System

The move from 1.5 Litre to a larger and more powerful 1.8 litre Atkinson-cycle, four-cylinder engine should significantly improve the power to weight ratio and the performance of the Prius. The current 1.5Lt Prius has always scored well in city driving due to it’s regenerative braking but it has been noticeably lacking in highway performance due to it’s small engine capacity and the additional weight of a battery pack compared to vehicles with similar engine capacity. Contrary to conventional wisdom, the larger engine actually helps improve highway mileage. By making more torque, the new engine can run at lower average rpm on the highway. When operating at lower rpm, the new engine uses less fuel..

Toyota has used an electric water pump for the first time that increases engine’s efficiency by removing auxiliary loads from the engine’s crankshaft. These loads, such as the power steering and the air conditioning compressor, are powered directly from the 500v battery at achieve much higher energy efficiency. The 1.8-liter Prius engine is the first Toyota engine with no belts under the hood. The 4 cyl VVT-I puts out 98 hp (72 Kw) @ 5,200 rpm with 105 lb/ft (142 Nm) @ 4,000 rpm compared to 76hp (57 Kw) and 82 ft/lb (111 Nm) in the current model.

The Hybrid Synergy Drive system in the 2010 Prius is 90 percent newly developed with significant improvements over previous models. These include a lighter continuously variable transmission (CVT), an improved inverter cooling system and improved control logic to enhance brake regeneration.

The electric motor is still a permanent magnet AC synchronous motor (BLDC). Power has been increased from 50kw (67hp) to 59kw (80hp) while the Electric only torque figure provided in this press release says 153 ft/lb but the current model Prius has 295ft/lb (400Nm) so we’ll take that as a Toyota typo. Toyota say net hybrid systems power has increased from 110 hp (82 Kw) to 134 hp (98.5 Kw)

Worlds lowest Cd

The aerodynamic design of the new 2010 Prius was an important factor. The goal was to create a wedge shape with steeply raked windscreen and square rear end corners to reduce aerodynamic drag. The overall height of the Prius is the same, but moving the top of the roof 3.9 inches to the rear alters the roof profile. This also allows for enhanced rear headroom and improved aerodynamics. The new Prius received more hours of wind tunnel testing than any other Toyota in history, resulting in the cleanest aerodynamic profile of any mass-produced vehicle in the world. By focusing on the shape of the body, underfloor, wheelhouse liner and shape of the wheels, the designers of the new Prius were able to reduce the coefficient of drag (Cd) value to 0.25, compared to 0.26 for the previous model. The airflow under the car was studied extensively. Engineers made changes to the shape of the fender liner, front surface of the underfloor, and added a fin at the rear floor cover to increase linear stability.


An optional sliding glass roof is packaged with solar panels, located over the rear seating area, that powers a new ventilation system. This solar powered ventilation system uses an electrically powered air circulation fan that does not require engine assist. The system prevents the interior air temperature from rising while the vehicle is parked, making the cool-down time shorter when the driver returns to the vehicle, thus reducing the use of air conditioning. As it is usually hottest inside a vehicle when the sun is shinning rightest this should prove an efficient way to power a cooling system.

The remote air-conditioning system is the first system in the world to function on battery-power alone and that can be remotely operated, so the driver can adjust the interior temperature for comfort before getting in the car.
Reducing the vehicle's power consumption, potional LED (light emitting diode) lamps are used for low beams and also in the tail and stop lamps. Air conditioning, a major energy drain, has been re-engineered to increase efficiency and cool-down performance. In addition, an exhaust heat recirculation system reduces heat waste by warming engine coolant during cold startup, for improved performance. It also heats up the passenger cabin more efficiently.

Lighter chassis

The hood, rear hatch, front suspension axle and brake caliper are made from aluminium and the use of super high-tensile steel in the rocker inner, centre pillar, and roof reinforcement form a roll cage like safety cell for the occupants in the event of an accident. The 0-to-60 acceleration has been improved to 9.8 seconds, more than a second faster and disc brakes are now used on all four corners, replacing the front disc/rear drum brakes in the current model. Anti-lock Brake System (ABS), Electronic Brake Distribution (EBD), Brake Assist (BA), electronic traction control (TRAC) and Vehicle Stability Control (VSC) are included with Toyota's standard Star Safety System.

Dynamic Radar Cruise Control system, using advanced millimetre wave radar, is an available option. The system also enables Lane Keep Assist, which helps the driver stay safely within the lane, and the Pre-Collision System, which retracts seatbelts and applies the brakes in certain conditions when a crash is unavoidable.

Next-generation Intelligent Parking Assist features simplified settings to help guide the car into parking spaces. A back-up monitor, which provides a view of rear obstacles when reverse is engaged, is available with an optional voice-activated navigation system.

2010 PRUIS PRELIMINARY SPECIFICATIONS

POWERTRAIN
1.8-liter four-cylinder engine with VVT-i
Engine horsepower: 98 hp @ 5,200 rpm
Engine torque: 105 lb-ft @ 4,000 rpm
Electric motor: Permanent magnet synchronous motor
Electric motor power output: 80 hp/153 lb-ft torque
Hybrid system net horsepower: 134 hp
Emission rating: SULEV (with AT-PZEV)
Electronically controlled continuously variable transmission
Drive System: Front-wheel-drive
Hybrid battery pack: Nickel-metal hydride
Estimated fuel economy: 50 mpg (combined)*
DIMENSIONS (inches)
Overall Length: 175.6
Overall Width: 68.7
Overall Height: 58.7
Wheelbase: 106.3
Ground clearance: 5.5
Coefficient of Drag: 0.25
Wheels: 15-inch alloy wheels
17-inch alloy wheels (optional)
Tire Size: 15-inch: 195/65R15
17-inch: 215/45R17 (optional)
Seating Capacity: 5
EPA class rating: Midsize
* Preliminary figure based on Toyota's internal testing. Actual mileage will vary.

DIY Honda Civic gets 95 MPG

It might look ugly but this 1992 Honda Civic has double the fuel mileage of a standard Civic simply by lowering the coefficient of drag (Cd) from 0.34 to 0.17 with a little engineering savvy and $400 worth of material bought the local hardware store. In fact the drag on this 350,000 miles (563,270 km) old Civic has been reduced to the point where it is virtually equal to the radical tear drop shaped Aptera which has a Cd of 0.15.

The car's builder Mike Turner says at a highway speed of 65 mph (105 km/h) he can routinely achieve a fuel mileage of 95 MPG (2.5Lt per 100km). The most obvious feature are the wheel covers and Boat Tail which were modeled on a Vintage German 1939 Maybach. The extended tail eliminates the recirculating, low-pressure eddy that forms behind "normal" cars and that act to slow them down. More subtle but just as important additions have been a fully enclosed undertray, the removal of wing mirrors and blocking intake vents at the front of the car and exhausting the radiator air out through the front wheel wells.

Using coast down tests and a SuperMID fuel consumption computer Mike’s next target is to improve mileage during night driving as he has calculated the electrical load from the lights are costing him 2 to 3 mpg with half of this loss being from the parking lights. Mike wants to replace the parking and dome lights with LED's. Check out the Aero Civic web site.

Raser Hummer H3 Series Hybrid 100mpg SUV

Video featuring a Raser modified Hummer H3 converted to Series Hybrid that they claim gets 100mpg in EV only mode. Read More

Tesla Roadster - Wrightspeed X1 - EV1 - RAV4EV

A British produced documentary featuring interviews with former EV1 and Tesla research engineer Wally Rippel and test drives of both the pre-launch Tesla Roadster and the Wrightspeed X1 with Ian Wright.

Thermoelectrics to replace car alternators and improve MPG

Thermoelectrics - the phenomena in which a temperature difference creates an electric potential - have been known about for almost 200 years, but practical applications have not been widespread due to their low energy efficiency. That may all now be about to change as Germany automakers Volkswagen and BMW have developed thermoelectric generators (TEG) that recover waste heat from a combustion engine.

According to a report by Prof. Rowe of the University of Wales in the International Thermoelectric Society, Volkswagen claims 600W output from the TEG under highway driving condition. The TEG-produced electricity meets around 30% of the car’s electrical requirements, resulting in a reduced mechanical load (alternator) and a reduction in fuel consumption of more than 5%.

BMW and DLR (German Aerospace) have also developed an exhaust powered thermoelectric generator that achieves 200 W maximum and has been used successfully for more than 12,000-km road use.

Thermoelectric refrigeration

Thermoelectric have been used for refrigeration utilizing the Peltier effect originally discovered in 1834. An electrical current at the junction of two different metals results in heat being absorbed by one metal and expelled by the other metal. Thermoelectrics can also be used to generate electricity using the Seebeck effect that dates back to 1770. Thermoelectric power generators convert heat energy to electricity. When a temperature gradient is created across the thermoelectric device, a DC voltage develops across the terminals.

Thermoelectric generators

Typical applications for this technology include providing power for remote telecommunications and navigation beacons. A more familiar application is a thermocouple that is a type of temperature sensor that can generate a current proportional to the amount of heat it is exposed to. Thermocouples were used in remote parts of Russian in the 1920s to power radios from a wood fireplace and they also form the basis of radioisotope thermoelectric generators (RTG) that use heat from a radioactive material to power deep space satellites. The drawback to all thermocouple based electric generation is that they are very inefficient at between 3-7%.

Automotive thermoelectric generators (ATEG) have been developed intermittently since 1988 when Porsche made a exhaust ATEG capable of 20-30 watts out of a 944 exhaust system but they have never made it past the prototype stage of development.

Regeneration no longer just about braking

Recent developments in regeneration technology are almost ready for prime time. Both Hydraulic Hybrid Vehicles and Power Generating Shock Absorbers are both being field tested and may be soon headed for mass production. UPS have committed to purchasing seven "series" hydraulic hybrid delivery vehicles while Electric Truck, LLC has exclusively optioned commercial rights to a technology from Tufts University that uses Regenerative Shock Absorbers to recharge the batteries of any hybrid electric and electric-powered vehicle while it is driven.

Regenerative shock absorbers

The regenerative electromagnetic shock absorber uses an electromagnetic linear generator to convert variable frequency, repetitive intermittent linear displacement motion to useful electrical power.
Tufts University claim the regenerative electromagnetic shock absorber technology was developed by Tufts engineering professor emeritus Ronald Goldner and colleague Peter Zerigian within the School of Engineering and received additional support in subsequent years from Argonne National Laboratory.

How it works

A conventional automotive shock absorber dampens suspension movement to produce a controlled action that keeps the tire firmly on the road. This is done by converting the kinetic energy into heat energy, which is then absorbed by the shock’s oil. The Power-Generating Shock Absorber converts this kinetic energy into electricity instead of heat through the use of a linear electric motor. The electricity generated by each PGSA can then be combined with electricity from other power generation systems (e.g. regenerative braking) and stored in the vehicle’s batteries.

The motor is usually a cylindrical 3-phase brushless permanent magnet linear electric motor that is sometimes referred to as a ServoRam. Early ServoRams were developed in the 1990s to replace hydraulic rams in entertainment motion simulators. Bose have also developed an Active Suspension System that uses linear stepper motors to replace standard shocks/springs. Bose claim they have been working on the software (algorithm as they call it) for 24 years (since 1980). The difference between the Bose system and power generating or regenerative shock absorbers is that the later retain standard coil springs to suspend the static load of the vehicle while Bose have deleted springs altogether.

Linear motors as replacement ‘shock absorbers’ are a much cheaper solution with more regenerative potential and have enormous potential in motorsport where shock absorbers could be constantly variable. An electromagnetic shock absorber could be tuned to respond to virtually any input. With regenerative shock absorbers connected to a microprocessor system with any number of inputs such as on-chip gyro, accelerometer, ride height and steering angle a 4-shock system can actively control a vehicles pitch, roll and yaw.

Since the technology actively uses the weight of a vehicle for energy recovery, it could help speed the expansion of the hybrid and battery electric vehicle market from cars to vehicles of greater size, weight and payloads, such as SUVs, pickup and delivery trucks, mail trucks, school and city buses and other light and medium duty trucks

Hydraulic hybrid regeneration

The UPS "series" hydraulic hybrid delivery vehicles have a diesel engine combined with a unique hydraulic propulsion system, replacing the conventional drivetrain and transmission. The vehicle uses hydraulic pumps and hydraulic storage tanks to capture and store energy, similar to what is done with electric motors and batteries in a hybrid electric vehicle. In this case, the diesel engine is used to periodically recharge pressure in the hydraulic propulsion system. Fuel economy is increased in three ways: vehicle braking energy is recovered that normally is wasted; the engine is operated more efficiently, and the engine can be shut off when stopped or decelerating.

The hydraulic series hybrid, originally developed in a laboratory of the US Environmental Protection Agency (EPA), uses a diesel engine/pump to pressurise and transfer hydraulic fluid to the rear drive pump/motor and/or high pressure accumulator. The hydraulic drivetrain replaces the conventional drivetrain and eliminates the need for a conventional transmission. UPS and the US Environmental Protection Agency (EPA) said the prototype vehicle had achieved a 45-50% improvement in fuel economy compared to conventional diesel delivery trucks.

Eaton began working with the EPA in October 2001 under a Cooperative Research and Development Agreement involving hydraulic hybrid systems and components. As part of Eaton’s role in designing and developing hybrid technologies, the company’s engineers were co-located at the EPA’s Ann Arbor facility. Eaton also earned a number of hybrid power system patents and continues to work on a number of other hybrid vehicle initiatives with UPS and others.

The EPA believes the technology can perform equally well in other applications such as shuttle and transit buses and refuse pick-up trucks. In 2007, the agency launched a project to develop hydraulic series hybrid systems for Class 6 port yard hostlers—the heavy-duty diesel’s that move goods and products from ships to trucks at ports.