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Considering the hybrid question
When futuristic, hybrid-engined cars first came to New Zealand attention, rumours did the rounds about them being tricky to repair and the batteries being difficult to replace and hard to recycle. CLiCK Me correspondent Mark Webster examines the hybrid question in light of a changing environment. The main concerns about cars used to revolve around carbon footprints and exhaust emissions – that was before the price of fuel went through the roof. Now you can happily (or not) add that to the list of issues a hybrid helps to address. Let’s be clear; a hybrid isn’t a full alternative to a petrol-engined car. It’s actually one motor made from two using a high-tech electric engine grafted to a standard petrol motor. A hybrid runs in one mode at low speed and then when the vehicle needs more power, the other component kicks in. Running on petrol helps charge the batteries, as does braking, and running electric saves fuel. All this is managed seamlessly and impressively by technology so sophisticated it scares many traditional mechanics. You might well ask, “why don’t we just have electric cars?” Fully electric-engined cars need either a constant power source – like a tram’s overhead lines or the electrified rails of a train system – or they need a good, powerful, long-life battery that needs periodic charging. But it turns out that using electricity for transport isn’t totally ecologically sound. While it’s clean – a fully-electric car doesn’t blow any kind of smoke – electric vehicles still need to get their power from somewhere. Whether they have the constant power source of trams or regularly charge their batteries, both methods impact on the electricity grid and if your electricity comes from nuclear or coal-fired power stations, welcome to another whole raft of issues to consider. So the hybrid car is the auto-industry's attempt to find the sweet spot between electric and fuel. Although they’ve been around for a while now, hybrids do cost more to buy than standard petrol or diesel-engined cars. But on the road, a hybrid definitely saves money. You still need to buy fuel – but less than normal. What’s more, they are eerily quiet when running; but any illusions about lack of power are dispelled when you put your foot down. Toyota took a huge risk when it launched the Prius a few years ago, and it has been suggested – somewhat cynically – that Toyota’s sales of SUVs, with their commensurate environmental impacts, paid for Prius development. In a Prius, the 1.5-litre engine operates constantly inside its peak efficiency range in stop/start city driving. This means the Prius offers twice the fuel efficiency of a conventional vehicle with only half the C02 emissions in town driving. At slow speeds, the Prius typically runs electric-only, requiring no fuel and producing no emissions. Toyota opted for a distinctive look for the Prius, making it almost instantly recognisable when viewed near other cars. Honda took a different approach, offering a smaller hybrid option in a Civic body. The 1.3-litre Honda hybrid looks just like any Civic except for the ‘hybrid’ badge. Honda’s hybrid also works differently to Toyota’s. It uses the petrol engine as the low-speed power source, adding electric power for a boost when the engine comes under load. In other words, with the Civic, more fuel is saved on open-road and hill driving than town driving. And Honda has a new hybrid hatchback in development that uses an even smaller, lighter engine with a continuous transmission and a nickel metal hydride battery pack. Ok, so what about the batteries? People do worry about them, but overall they appear to be very hard wearing. According to the AA some vehicles have clocked up 300,000-plus kms overseas on their original batteries. The current retail price for replacement batteries is around $6000, but this cost is likely to decrease. Toyota NZ currently offers an eight-year warranty on Prius batteries as part of the new car warranty programme for vehicles sold through the their dealer network. According to Toyota NZ should a battery fail or need to be disposed of, it gets sent off to Toyota in Japan where each part is either used in new batteries or recycled. In effect, nothing ends up in a landfill which is comforting to the greener consumer. A recent addition to the hybrid flock is the recently launched Toyota Lexus luxury hybrid [www.lexus.co.nz/PerformanceHybrid/]. Using a high performance petrol engine component synchronised with electric energy, the Lexus Performance Hybrid has been developed to deliver more acceleration with lower fuel consumption and CO2 emissions. Like the Prius, the petrol engine generates all the electricity needed. Under braking, kinetic energy is converted to additional electrical energy which is used to help charge the battery. Test driving a Prius The eponymously named Campbell Green has owned a Prius for a year, along with a secondary, smaller petrol-engined car. Green uses the car for “everything, except when we really need to use two cars at a time.” He bought the car for environmental reasons and because of fuel prices. “We had a three-litre vehicle that was costing over $100 to fill and we were getting only 450-500 kilometres from it. Back then it cost me $60 to fill the Prius, but I got almost 850 kilometres out of it.” Despite some longer drives of about 240 kms, the Prius has performed well with no problems. It also easily copes with loads – as Green says, “this thing generates +400nm of torque through electrics up to 50kms per hour!” That’s an impressive figure for the size of the engine. Green says the torque feels constant at all speeds, which makes for interesting driving as you always seem to get smooth acceleration: “I notice some cars have difficulty keeping up with the acceleration when I pass slow trucks or cars on the open road.” Overall Green’s convinced of the benefits of a hybrid. “We love our Prius and will never go back.” With fuel prices as they are and environmental concerns growing, we can look forward to more companies launching hybrid vehicles, including heavy vehicles, in the not too distant future. Links: Land Transport’s NZ Fuel Saver site: www.fuelsaver.govt.nz Toyota Prius: www.toyota.com/prius-hybrid Lexus Hybrid: www.lexus.co.nz/PerformanceHybrid Honda Civic Hybrid: www.honda.co.nz/site/new_cars/civic_hybrid/index.html 
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