Every self-respecting car maker needs an eco-friendly vehicle in its range. No manufacturer accepts blame for global warming, but most accept they are going to be demonised if they don’t appear to do something about it.
To be fair to the industry, the government’s latest figures show that passenger cars accounted for 13% of carbon dioxide (CO2) emissions in Britain in 2003. This is less than residential emissions (15%), manufacturing industries (15.7%) and less than half produced by the energy industries (38.1%). If you take account of the large amount of CO2 given off by livestock then cars account for an even smaller share. And commercial flights give off more CO2 per passenger kilometre than most modern automobiles.
By no means everyone acknowledges a link between man-made CO2 and global warming in any case. Nonetheless, there are 30m cars on UK roads alone, each pumping hundreds of kilograms of CO2 into the atmosphere every year. The number is growing, as is the average number of miles travelled each year.
The other issue is oil. President George Bush said in his state of the union address last week that the world needed to find alternative energy sources. “America is addicted to oil,” he said. “The best way to break this addiction is through technology.”
If you want to be greener than your neighbour there is a range of eco-friendly cars to choose from. We tested the four main types to assess what they would be like to live with on a daily basis, taking into account cost, emissions and practicality.
It’s worth remembering, by the way, that Rudolf Diesel, who in the 19th century created the engine type that bears his name, would probably find the rush for alternatives amusing. His idea was that his invention should run on hemp oil or peanut oil — not so far removed from rapeseed biodiesel and recycled chip fat that is being used today in some diesel engines.
Hybrid power: Toyota Prius
Petrol-electric hybrids use a conventional petrol engine that is assisted by a battery powered electric motor. The battery is charged by the engine and from energy that would otherwise be wasted during braking.
The Prius is by far the best known and bestselling of the petrol-electric hybrids and on paper its environmental credentials appear exemplary. The system of switching from electric to petrol power means that at low speeds it runs solely on battery energy, making it the cleanest vehicle on the road, while at higher speeds the petrol engine ensures its performance remains acceptable.
To drive the car takes a little getting used to: it runs in complete silence on its electric motor alone. But once you are acclimatised it is a perfectly practical if expensive five-seater family hatch offering reasonable performance and, in London, congestion-charge exemption. Keep the Prius in town, where it can make most use of its electric motor, and it’ll return 56.5mpg. Not only that, but when it runs on electric power alone it is a true zero-emissions vehicle, something that can be said for few other cars save its big brother the Lexus RX 400h.
On the open road, where you rack up the most miles, its advantage over the opposition is nothing like as clear cut. Indeed its fuel consumption (65.7mpg combined) is likely to be little if any better than that of a conventional comparable diesel car. For comparison, the most fuel-efficient standard car on the road, the Citroën C1 1.4 HDi Rhythm, manages 68.9mpg (the petrol version achieved a stunning 85.5mpg combined in a Sunday Times test), with CO2 emissions of 109g/km and a price of £8,525. Even a Ford Focus 1.8 TDCi, just as quick in acceleration as the Prius, will get just 1.6 fewer miles from a gallon of fuel when gently driven.
CNG: Volvo V70 2.4 S
Compressed natural gas (CNG) is methane, a relatively cheap fuel source. It is around half the price of petrol and offers emissions reductions — 60% less carbon monoxide and 10% less CO2. The problem is availability. Although natural gas has been around since the 1930s there are still only a tiny number of filling stations — just 15 in the UK — and so far Volvo is the only manufacturer to offer CNG-powered cars. CNG manages only half the range of the equivalent weight of petrol and therefore requires large fuel tanks. The CNG-powered Volvo has lost the spare tyre to make room, but also has a conventional fuel tank half the normal size (you need a conventional tank in case you run out when you are nowhere near one of the 15 CNG filling stations, which is likely to be most of the time).
Unless you happen to have a CNG supplier on your doorstep, driving a gas-powered V70 in real life will be very much like driving a normal V70, except it costs over £3,000 more to buy.
There’s little prospect of the situation changing much, either.
When liquefied petroleum gas (LPG) and CNG were first offered to the market they were touted as equivalent technologies, much like VHS and Betamax video formats in the 1980s. We asked Volvo to tell us exactly how many CNG-powered V70s it sold in the UK last year, to which a brave and honest spokesman replied: “Er, one.” We hope its new owner likes the car very much — he may find himself owning it for rather a long time.
Bioethanol: Saab 9-5
Bioethanol fuel comprises 85% bioethanol (produced by the fermenting of renewable crops such as wheat or sugar beet) and 15% petrol. It is often called E85 and is capable of reducing CO2 emissions by 70%.
This is not achieved through less emissions from the exhaust (these are roughly the same as a conventional engine), but by the way the emissions are balanced by the amount of CO2 removed from the atmosphere through natural photosynthesis, when the crops for conversion to bioethanol are growing (the argument for using biodiesel, which is produced from new and recycled vegetable oils, is the same).
The Saab 9-5 BioPower we tested arrived in Britain in December and is available later this month. Unlike the Toyota Prius, which charges a hefty premium for the added technology, the Saab costs just £600 more than a standard version (prices begin at £21,651 for the saloon and £22,851 for the estate). This is because minimal modifications are needed to enable the engine to run on the fuel. Saab says that maintenance and servicing costs are expected to be the same as for conventional cars, too.
Uniquely among alternative fuels, bioethanol improves performance. It boasts a higher octane rating than petrol, meaning the Saab 9-5 BioPower has 20% more bhp, more torque and better acceleration: 0-60mph in 9sec in the bioethenol version compared with 9.8sec from straight petrol.
Unlike CNG there is only one fuel tank and the engine-management system is able to cope with a variety of fuel blends, ranging from 85% bioethenol to 100% petrol with no input required from the driver.
However, there are downsides. The fuel is still in its infancy in Britain and there are no financial incentives to encourage people to take up the option. E85 costs the same as petrol, while the cars will still be liable for the congestion charge in London, unlike the Prius. There is also little difference in fuel economy between the BioPower and a conventional Saab.
The main drawback, however, is that there are few service stations that stock E85. At present only a handful of supermarkets in Somerset have agreed to sell it.
An increasing number of service stations do now stock a weaker blend of bioethanol fuel, typically comprising 5% bioethenol and 95% petrol (around 250 Tesco forecourts stock it, although the pumps themselves do not show that the standard unleaded fuel contains bioethanol).
The alternative is to buy a normal diesel car and run it on biodiesel, which is stocked at a growing number of filling stations (visit www.biodieselfillingstations.co.uk for a full list). Availability of biofuels is likely to increase under the government’s renewable transport fuel obligation, which states that 5% of all car fuel must come from renewable sources by 2010.
LPG: Vauxhall Zafira
LPG has been an alternative fuel for years and was widely used as early as the 1980s in cars in New Zealand.
It is reasonably green (typically releasing around 12% less CO2 than petrol), cheap (about half the price of petrol) and relatively easy for drivers to convert to.
The Vauxhall Zafira 1.8 we tested was converted for the car maker by a specialist subcontractor, but there are an increasing number of independent companies that will convert virtually any car to run on LPG (www.lpga.co.uk includes a network of approved converters). It is important you check with the manufacturer about whether a conversion will affect the warranty (invariably it will) and inform your insurance company of the change. Most will provide cover as long as it has been carried out by an approved company.
The conversion includes fitting an auxiliary LPG tank, a regulator, fuel- injection system and electronic control module. The first Dualfuel Zafira used Vauxhall’s 1.8 litre Ecotec engine (the 1.6 model followed later). To make room for the additional 50-litre (11 gallon) tank that slots into the spare-wheel well, the LPG Zafira doesn’t carry a spare. Instead Vauxhall offers a tyre-inflation kit.
The combined fuel consumption figure for the 1.8 litre engine running on LPG is 24.8mpg (the urban driving figure is 18.4mpg and extra-urban is 31.1mpg) while CO2 emissions are 184g/km.
Although cars do fewer miles to the litre on LPG fuel (about 25% less) its lower price means that savings still amount to 40% over petrol and 20% over diesel, according to the LPG Association. Of course, you will only actually be making a saving when you have paid off the cost of the initial conversion, typically £1,500 but, depending on the size of the tank and make of your car, anything up to £2,000. For this reason it is an option best suited to high-mileage motorists.
The chancellor, Gordon Brown, announced in his March 2004 budget that duty on LPG will be increased by 1p per litre each year to 2007-8, although it will still be cheaper than petrol. Importantly, because LPG is a by-product of crude oil distillation, it is not a way of reducing dependence on fossil fuels.
About 120,000 cars and small vans in Britain run on LPG and there is a network of around 1,300 garages that sell the fuel (www.lpgmap.co.uk), making it the most user friendly — if not the most environmentally friendly — of the alternative fuels available.
One more thing; if your car is LPG powered you can’t take it through the Channel tunnel, because of a perceived extra risk of explosion.
The future
The holy grail of car makers is the hydrogen fuel cell. This combines hydrogen and oxygen into water and, in the process, creates the electricity that is used to power the car. The only thing that comes out of the exhaust pipe is pure water. However, while all the main car manufacturers are experimenting with prototypes, a feasible and affordable finished product is at least 10 years away from the showrooms.
For many, the next best thing in terms of what is achievable in the short term is refining the hybrid technology seen on the Prius to make it even more efficient. The most obvious way of doing this is to make a hybrid diesel: not only do modern diesel engines have vastly superior economy, they also produce less CO2. Combining them with a battery motor would be the best of both worlds.
The problem has been that it was considered impractical, due primarily to the extra weight of diesel engines. However, last week PSA Peugeot-Citroën became the first car manufacturer to announce the production of a diesel-electric hybrid. The Peugeot 307 and Citroën C4 Hybride HDi models will go on sale in 2010 and The Sunday Times has already driven the prototypes.
The cars feature the 90bhp 1.6 litre HDi engine already available in both the C4 and 307 but combine it with a 23kW electric motor. The battery pack is located under the boot floor in place of the spare wheel (the hybrid vehicles will use run-flat tyres).
The hybrid diesel will have a combined fuel consumption of 83.1mpg — 28% more than the standard HDi. For comparison the Prius achieves 65.7mpg and emits more CO2 — 104g/km versus 90g/km for the C4/307 models. Even when using just battery power it will be capable of 37mph with a range of around three miles. PSA claims the hybrid will cost about £1,000 more than a standard diesel version. “The performance of a gasoline hybrid is similar to that of a standard diesel engine,” says Robert Peugeot, PSA’s executive vice-president of innovation. “Only by combining hybrid and diesel technology can we achieve a major improvement in fuel efficiency, without compromising performance.”
Additional reporting: Jeremy Taylor, Joseph Dunn and Alistair Weaver
