Electric vehicles – hybrids (4)
Hybrid vehicles powered by either or both electricity and fossil fuel are far from new. In 1898, Ferdinand Porsche developed a hybrid car (the Lohner-Porsche). Its petrol-fuelled engine ran a generator powering electric motors built into the front wheels. The car had a range of almost 60 km from batteries alone.
The 1898 Lohner-Porsche- the first hybrid car. Pic: Original source not known.
In 1905, American H. Piper applied for a patent for a petrol-electric hybrid vehicle able to accelerate to 40 km/h in ten seconds. His patent, however, took so long to be granted that by the time it was, petrol-fuelled vehicles had advanced to have much the same performance.
Woods Motor Company Dual Power
The best-known early hybrid is the Woods Motor Company Dual Power Model 44 Coupe. It was made during 1917-1918, and based on a patent of Roland S. Fend.
The vehicle had an inline 1.1 litre four-cylinder 10.5 kW petrol engine coupled to a 48 volt compound-wound (i.e. both series and parallel winding) via an electromagnetic clutch. The motor was powered by a pack of 115 Ah Exide lead acid batteries (about half the capacity of electric car batteries of today). Below 24 km/h the car ran from the electric motor. Once over that, the petrol engine would start up and could power the vehicle to about 55 km/h.
The Woods petrol-electric hybrid. Pic: courtesy of Petersen Automotive Museum Archives
When the electromagnetic clutch was engaged, the petrol engine drove the car’s rear wheels through the electric motor’s armature shaft. Some sources claim the car had magnetic transmission (as in Wood’s patent) – but existing examples show that is not so. Much like hybrid cars of today it had regenerative braking.
The Woods car ran on petrol, electricity or both. It was promoted as ‘a self-charging, non-stalling, two-power motor with unlimited mileage, adequate speed and greatest economy.’ Among other claimed advantages were 40% higher speed than most electric cars, no gear lever or clutch, ease of operation, lessened maintenance and no need for a home charger or public charging station.
Once the electric motor’s torque got the vehicle moving (thus doubling as a starter motor) the petrol engine could propel it at moderate speeds. Whilst doing so the electric motor’s function was reversed: once the petrol engine was running the electric motor acted as a generator that optionally charged the car’s batteries. Reversing was effected by causing the DC electric motor to run backwards.
Sadly, only a few hundred of Woods Dual Power Cars were sold. This was probably due in part to its high price, but also because the first era of electric cars was coming to an end. Apart from being much quieter, even the best could not compete with Henry Ford’s petrol-powered Model T once a wider fuel distribution network was established.
Furthermore, because rechargeable battery development (re capacity per volume and weight) had barely improved since their commercial inception, there was little incentive to develop electric motive power until quite different incentives arose.
Almost all hybrid development re-arose in the USA and Japan. In response to rapidly increasing air pollution (particularly in California) the U.S. Congress, in 1966, recommended using electric-powered vehicles. One result (in 1969) was General Motors’ experimental hybrid car - the GM 512. It used electric power to 16 km/h, then both electric and a (two-cylinder) petrol engine power until 21 km/h. It then ran only on petrol. Its maximum speed was about 65 km/h.
The Arab oil embargo (1973) increased interest in electric powered vehicles. One result was Volkswagen’s experimental petrol and battery powered hybrid - but it did not go into production. Another result (in 1975) was the US Postal Service trialing battery-powered delivery vans.
In 1976, the (US) Electric and Hybrid Vehicle Research, Development, and Demonstration Act encouraged industry to develop hybrid-electric components. At that time also, Toyota built its first (experimental) hybrid: using a gas-turbine generator for its electric motor.
In 1980, lawn-mower engine maker Briggs and Stratton developed a hybrid car driven by its twin cylinder four-stroke Baldo engine of a mere 6 kW that ran on ethanol, an electric motor, or both. The car’s twin rear wheels were needed to cope with its 500 kg or so lead acid batteries. It could travel 50 to 110 km in electric mode and about 320 km in hybrid. The car was primarily a promotion for its lawn-mower engines as, to put it mildly, its adverse power/weight ratio ‘limited performance’.
The Briggs and Stratton hybrid. Impressive visually –but seriously underpowered.
Pic: Briggs & Stratton.
A battery boost
A major boost for hybrid vehicles was the USA’s (1991) ‘Advanced Battery Consortium’ aimed at producing a more compact battery. The reported US$90 million cost resulted in the nickel hydride battery of about three times the capacity of lead-acid batteries of similar size and weight. Whilst its capacity/weight ratio was still less than really needed, it enabled a new generation of practical electric vehicles – hybrid and otherwise.
Toyota’s ‘Earth Charter’
In 1992 Toyota’s ‘Earth Charter’ outlined an intention to develop and market vehicles with the lowest possible emissions: ‘to dedicate our business to providing clean and safe products and enhancing the quality of life everywhere through all of our activities’.
Also that year, the USA’s ‘Partnership for a New Generation of Vehicles’ sought low emission cars consuming less than 3.0 litres/100 km. Three prototypes (all hybrids) resulted – but Toyota was formally excluded from participating.
That (seemingly extraordinary) decision prompted Toyota to create the first Prius, model NHW10. It went on sale in Japan in December 1997, just prior to the Kyoto global warming conference.
The original (1997) model NHW10 Toyota Prius. It was sold only in Japan but some were imported privately into many countries. Pic: Original source unknown.
The initial (NHW10) version’s petrol engine produced 43 kW. Its electric motor produced 29.4 kW with torque (at zero rpm) of 305 Nm. It was powered by nickel-metal hydride batteries.
The model later sold in European and the USA (from September 2000) was the NHW11 version. It had a petrol engine producing 53 kW and 115 Nm torque and was an instant success. Some buyers waited six months for delivery.
The official launch of the Toyota Prius in Australia was in 2001.
Hybrid development in Europe was delayed following Audi’s (1997) unsuccessful attempt to sell such vehicles in volume. Based on its A4 Avant, the car was powered by a 67 kW 1.9-litre turbo-diesel engine and a 21.6 kW electric motor via a lead-acid gel battery.
It did not sell as hoped, causing Europe’s car companies to concentrate on reducing diesel emissions. Doing so proved to have major limitations – to the extent that some makers illegally disguised their true levels.
European makers’ failure to realise, let alone accept, that diesel engine emissions could not be reduced to ongoing EU requirements, resulted in almost all initial electric car and hybrid development being done in the USA and Asia.
Progress in Europe was thus initially slow, but now (mid 2019) there are European designed and made electric-only cars and hybrids of all shapes and sizes.
Owned by BMW the first Mini hybrid, the Countryman S E ALL4 is scheduled for sale in Australia during the latter part of 2019.
Mini hybrid –the Countryman S E ALL4. Pic: https://www.mini.co.uk
Sharing some of the underpinnings of BMW 2 Series Active Tourer plug-in hybrid, its front located three-cylinder petrol engine develops 100 kW and drives its front wheels via a six-speed automatic gearbox. A 65 kW electric motor drives the rear wheels – also providing optional 4WD. The 7.6 kWh battery enables an electric-only range of about 40 km. BMW states that it aims to have all of its vehicles with a choice of petrol or diesel engines, hybrid or all-electric propulsion.
In Europe at least BMW’s hybrid, (that used a 0.65 litre petrol engine to charge the drive battery (if needed), has been replaced by an all-electric version. The battery (now 42.2 kWh) enables a claimed range of about 310 km. This suggest that, as battery technology improves (and more grid power is from wind and solar) the days of hybrids may be over.
Porsche has two hybrids. The 2019 Cayenne E-Hybrid has a 3-litre turbocharged petrol engine and a V6 engine and a single electric motor located between the transmission and engine.
The petrol engine can produce 250 kW 335 HP and 450 Nm of torque while the electric motor adds an additional 100 kW plus 400 Nm of torque.
The Porsche Panamera 4 (hybrid) is much as the Cayenne hybrid, but its Turbo S E-Hybrid has a twin-turbo 4.0-litre V8 petrol engine of over 505 kW and 850 Nm. It is claimed to have an all-electric range of 22.5 km and to use 4.9-litre of petrol per 100 km.
Volvo has reconfirmed its goal of selling one million hybrid vehicles. Its forthcoming V40 will have a choice of engines: plus a rear axle-mounted electric motor.
Hybrid off-road vehicles
Hybrid drive trains work well with off-road vehicles as the electric motor increases overall power and the fossil-fuelled motor extends the overall range. There is also little choice: few existing such vehicles will meet the 2020 Euro 7 Emissions requirements. Fortunately, many existing 4WDs have ample space for batteries – thus easing conversion.
The Lexus RX 450h retains its existing 3.5-litre V6, but has three electric motors energised by a 123 kW battery which marginally increases power (from 221 kW to 230 kW) and reduces fuel consumption from 9.6 litres per 100 km/h – to 5.7 litres per 100 km. There is also a three-row version that, being slightly heavier, uses marginally more fuel.
Lexus 450h (2019) Pic: Toyota
The Mitsubishi Outlander LS and Exceed each has a two-litre petrol engine and two electric motors. They can travel up to 55 km on their lithium-ion batteries and have a claimed fuel usage of 1.7 litres per 100 km. A minus is that the Outlander model is reduced to a five seater (to free up space for the batteries).
Mitsubishi (2019 Outlander hybrid. Pic: MitsubisiNissan’s
Pathfinder Hybrid is available in 2WD or 4WD variants. Each has a 2.5-litre cylinder supercharged petrol engine of 201 kW and 330 Nm. The 10 kW electric motor is powered by lithium ion batteries, charged by the engine’s alternator and also by regenerative braking.
Fuel use is reduced to a claimed 8.6 litres per 100km – down from about 10 litres per 100 km for the equivalent V6 non-hybrid models. Why the product has no provision for grid or other charging is unclear, but at least simplifies usage.
Subaru’s current XV model is to become a petrol-electric hybrid by the end of 2020. The existing 2.0-litre petrol engine and automatic transmission is to have a 10 kW electric motor to ‘assist smooth acceleration’. The maker claims that the current fuel usage (of 7-litres per 100 km) will be reduced to 5.2 litres per 100 km.
The Range Rover hybrid has all-new light alloy monocoque construction and unusual in being diesel-electric, rather than the generally used petrol-electric. At almost A$150,000 upward they are far from cheap but (as with their Land Rover counterparts) are serious four-wheel drives (not SUVs)
They have a 215 kW (520 Nm torque) diesel engine, plus a 35 kW electric motor (170Nm torque built into the 8-speed gearbox) developing a claimed total of 250 kW and 700Nm from 1500 to 3000 rpm...The electric motor is powered by a liquid-cooled lithium-ion battery pack within a protective underfloor cradle. Regenerative braking assists charging in stop-start driving - both in city and some off-road usage in hilly going. Diesel capacity is 80 litres.
The Range Rover Evoque hybrid. Pic: landrover.com
The claimed (Australian Design Rules) fuel usage is 5.8 litres per 100 km but independent tests report it to be closer to 7-9 litres per 100 km.
The hybrid’s Range Rover’s main benefit is sometimes quieter going and greater acceleration as long as the battery has adequate charge. Its towing capacity is a claimed 3000 kg.
By and large the Range Rover is a brand name of the original ultra-rugged Land Rover 0riginally developed by Rover (in the UK in 1948). It has been owned by India’s Tata Motors since 2008. Tata Motors has now created distinct images for what is essentially much the same vehicle - but with subtle differences.
The Range Rover is both marketed and perceived as being an up-market vehicle used mostly for suburban driving such as taking the kids to and from school and also towing the smaller up-market caravans. It is a sort of high status limo without looking like one. A Range Rover is capable of crossing the Simpson Desert – but is mostly shown in promotions dropping VIPs off at the local Hilton.
The Land Rover is (now) much the same vehicle but marketed as a more serious 4WD and promoted accordingly. A Land Rover is not necessarily cheaper, a few models (e.g. the LR4 HSE LUX) were more costly than many Range Rovers.
A new Land Rover Discovery Sport hybrid is expected to be available in Australia in late 2019 (or early 2020) and as with its associated products to have a hybrid power train. Full details are not currently available.
Hybrid vehicles and emissions
When comparing overall CO2 emission, of electric versus petrol or diesel cars, the efficiency of charging from fossil-fuel fed power stations must be taken into account. Most convert about 38% of their resultant heat into usable energy. Petrol burned by cars converts only 25%.
Energy is also lost in producing petrol and diesel, conveying electricity from power station to electric outlets, and in charging electric (and hybrid) car batteries.
A 2019 petrol-fuelled car typically emits 345-350 gram of CO2 per km, an electric-only car of the same size emits 150-155 gram of CO2 per km. A Prius Hybrid emits 107 gram of CO2 per km. An electric-only car charged from the Australian grid network thus has about half the emissions of a similar sized petrol fuelled car. Hybrids typically emit less than one-third.
Solar-powered electric vehicles
If adequate solar energy is available an all-electric car is by the least polluting.Battery making is seriously polluting – but is common to hybrid and all-electric cars – excepting the latter have larger capacity batteries. See also Solar Charging Your Electric Car at Home.
No electric car seems likely to be made in Australia. An initially promising all-terrain electric car (the Tomcat) was designed and built in 2012. The first 100 sold out almost immediately, but high manufacturing costs (and investor concerns) resulted in the company entering voluntary administration in February 2018.
The all-terrain electric Tomcat – sadly no more. Pic: Tomcat