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Full details of the new Honda Insight have been announced – except for the price – which will be available nearer to the on-sale date in April. However, Honda is still shouting about the fact that the 5-door family hatchback with its petrol-electric IMA system will be the most affordable hybrid on the market. So that means it will be cheaper than the Toyota Prius, which starts at £17,870. In reality, it’s likely that the Insight will cost around £15,000.
The Insight 1.3 IMA SE can manage 64.2 mpg and emissions of 101 g/km CO2. This is great but why on earth has Honda not made an effort to drop the emissions by an extra 1 or 2 g/km to get a 100 or 99g/km figure? The Insight 1.3 IMA ES / ES-T, both with more equipment, can only manage 61.4 mpg and emissions of 105 g/km CO2.
Honda has aimed in its development to reduce the size, complexity and price of components and systems. And because the major hybrid components in Honda’s cars are produced in-house, this also helps to control overall costs.
The company claims that the fuel economy figures can be matched in everyday driving. And it comes with Eco-Assist, a driver coaching system developed for the Insight, which will train drivers, helping them achieve the best possible fuel economy.
Honda has avoided going down the diesel route as diesels produce higher levels of NOx and particulate emissions; as a result, there are increasingly stringent Euro 5 and 6 regulations. Manufacturers will have to fit expensive diesel particulate filters to meet these standards, thus adding potential additional cost to the on-the-road price of their cars.
Honda has ignored the wishes of Americans and gone for a hatchback rather than a boot for the European market. Hatchbacks are also a more aerodynamic shape.
Because of the electric motor and the additional battery found in a hybrid vehicle, it’s been claimed that there’s a significant environmental cost to producing hybrids, perhaps even outweighing the environmental benefit of the cleaner tailpipe emissions.
As a matter of course, Honda carries out a Life Cycle Assessment (LCA) programme which looks at the CO2 emissions at each stage of a car’s life cycle, including production.
Honda further developed this programme in 2007 to introduce a product specific LCA system to investigate the volume of CO2 emissions associated with the whole life cycle of each Honda vehicle. This allows Honda to compare the environmental impact of the manufacturing stage and indeed the whole life cycle of our hybrid cars.
The findings demonstrated two things: the importance of the ‘use stage’ in a car’s life cycle CO2 emissions; and that the fact there’s very little difference between the CO2 emissions associated with the raw material and production stages of Honda’s hybrids compared to their conventional cars.
Honda’s IMA hybrid system is now 10 years old – having made its debut in the original Insight back in 1999. IMA stands for Integrated Motor Assist, which means that an electric motor sits alongside the petrol engine it supports and in front of the transmission.
This system has been used successfully in not only the Insight, but also the Civic IMA, and its successor, the Civic Hybrid. Over the years the system has evolved and become smaller, more lightweight and cheaper to produce, and the latest version in the new Insight is the most advanced IMA technology introduced by Honda to date.
The engine itself is new, but is based heavily on the 1.3-litre petrol unit from the Civic Hybrid. This modified i-VTEC unit from the Civic Hybrid has been further enhanced with lessons learned from the Jazz incorporated to improve fuel economy.
The low friction, pattern coated piston design has been combined with a new catalyst design to optimise its already economical design. These measures, along with a more stabilised combustion process help make the engine incredibly fuel efficient.
However, the really clever part happens during deceleration, when the engine’s cylinders have their feet up.
During this idle time, combustion in all four cylinders is stopped and each pot is sealed shut. This means the engine is not working as hard to pump fuel or air, so it’s immediately more efficient.
The technology used to shut the cylinders, VCM (for Variable Cylinder Management), is also used to shut all four cylinders when only little torque is required – during low speed cruising for example. In this mode the Insight is powered by the electric motor only, with the pistons running idle.
In addition, virtually everything possible has been done to the engine to reduce friction, including an offset crankshaft/connecting rod design, plateau honing of the cylinders for a smoother surface and a second low friction piston ring.
On its own, the engine produces 88PS and 121Nm of torque (89 lb.ft), but the key to hybrid systems is the support given by the electric motor that can help boost performance as well as keep emissions and fuel consumption to a minimum.
As well as a new engine, the Insight gets a new, improved motor which uses coils with high-density windings and high-performance magnets to produce 14PS and 78 Nm (58 lb.ft).
But the real step-forward with the motor has been its size and shape – the latest version is much thinner than the motor in the current Civic Hybrid (35.7mm vs 61.5mm), which means the entire IMA system is more compact and lightweight.
Improvements have also been made to the high-power, nickel-metal hydride battery, which is located under the boot to help lower the centre of gravity.
The cooling system for the battery has been much improved, which means it’s more efficient in its use of power, and can feed it to the electric motor more often.
A motor on the side of the battery pack draws through air from pipes leading to intakes outside of the rear seal bolster in the car (on the Civic Hybrid, the air intake is on the parcel shelf, which can be obstructed).
The recovery speed of the battery has also improved, meaning that with power from regenerative braking, it can charge more quickly and therefore deliver power to the electric motor more regularly.
When combined, the motor and engine produce lively performance ideal for urban environments, with good throttle response and acceleration times to rival conventional 1.6-litre petrol cars with automatic gearboxes.
The Insight reaches 62mph from a standing start in 12.5 seconds, and has a top speed of 113mph.
Using a CVT transmission in a hybrid provides smooth and predictable gear transitions and helps keep the IMA system operating at its peak efficiency.
In the Insight, an evolution of the high-torque CVT unit from the Civic Hybrid is used.
For the first time on a Honda hybrid, the Insight benefits from paddle shifts, so quick gear changes can be made from levers just behind the steering wheel (ES models).
While all hybrid cars have both an internal combustion engine and an electric motor, there are three main types of technology offered by different manufacturers. The first is the Series hybrid, which is driven solely by an electric motor. A combustion engine is used to generate electricity to power the motor.
The second type is called a Parallel hybrid, which uses the petrol engine as the main source of power to drive the car. The electric motor assists the engine, and at times even powers the car on its own. This is the system used by Honda hybrids – the system we call Integrated Motor Assist.
The other kind of hybrid is known as Series Parallel or Combined hybrid. This is the type used by the Toyota Prius, and it uses elements of both the parallel and series hybrid systems. This system has two electric motors and an engine, and each can be used independently of one another.
Each system has its advantages and disadvantages, but the biggest benefit of a parallel system, like IMA, is that it’s much smaller and lighter than the others. It also tends to be much cheaper to produce. Honda has focussed on optimising the parallel system over the past decade, which helped it bring Insight to market at a lower price.
The Environmental Protection Agency in the US (www.epa.gov) has developed a section on its website in which visitors can log the latest mpg of their current car, and see how other cars on the market are performing. Honda engineers used the results of these charts to benchmark the actual fuel economy of the Insight.
From 2010, the EPA is set to introduce a new method to determine fuel economy estimates.
This test is based on the results of five different driving modes, including cold temperature, air conditioning use and high speed acceleration.
Similarly, Japan’s new JC08 test cycle (due to begin in 2010) has been designed to include more cold engine starts, repeated stop/go accelerations to 40mph and other new driving modes more representative of everyday driving.
A few years ago, while monitoring customer use of the Jazz, the Insight development team found that there were significant differences in the fuel economy achieved from one driver to another. For example, at an average speed of 20mph (30km/h), there were differences of up to 21 per cent in the actual mpg being recorded by different drivers. With this in mind, the engineers tweaked the car’s management system in an attempt to minimise the effect of varying driving styles on fuel economy. When the tests were repeated, the least efficient drivers improved their results, and the difference between all the results was reduced to 12 per cent.
Honda has taken these learnings into the development of Insight, and the result is the ECON switch. When activated by the driver, this switch tells the car’s management system to adopt specific settings to improve fuel consumption. It does this without affecting overall safety levels or the general usability of the car.
When the ECON switch is depressed, the Insight enters a ‘super economy’ mode, resulting in the following:
* Power output is limited and torque is reduced by four per cent (except when driver pressed throttle to the floor)
* Smoother CVT shift pattern
* Throttle control is modified. At any engine speed, there is an optimum throttle angle, which if maintained, results in the best fuel efficiency. But some drivers apply a more on/off approach to throttle control, often pressing the accelerator down too far. To counteract this, the system ‘smoothes out’ driver input by maintaining the throttle opening to match the speed and conditions. The driver can override the system at any time, to perform an emergency manoeuvre, for example
* Greater regenerative brake energy is captured
* Air conditioning operates more frequently in the recirculation mode
* The fan blower power is reduced more frequently to limit the system’s consumption of energy
* During Idle Stop mode (the engine turning off when the car is stationary), the air conditioning shuts down.
There are driving styles and techniques that can be employed to take greatest advantage of the hybrid technology.
Driving as smoothly as possible, without heavy acceleration or braking, reduces excessive fuel consumption and allows the high-power battery to remain charged, which in turn means it can power the electric motor to support the engine more regularly, resulting in greater fuel economy. And driving without a heavy right foot generally equals better fuel consumption anyway.
That may sound easy in theory, but in practice it can be tricky to change the way you’ve been driving, in some cases for decades. We’re not expecting everyone to know how to drive like an eco-warrior – or indeed, to have to monitor the way they drive to eke more miles from a tank of fuel.
Instead, Honda has developed some useful technology to help Insight owners become more efficient behind the wheel called Eco Assist.
Together with the ECON switch, Eco Assist can be used to achieve high fuel economy and thus minimise harmful exhaust emissions.
During driving, there are two main elements to the system: an ‘Eco drive bar’ indicator within the black and white Multi Info Display (MID), and an ambient meter behind the digital speedometer display. Both instruments are synchronised, to give ‘real time’ information on the consumption of fuel and provide guidance on how you should alter your driving style.
The ‘eco drive bar’ in the MID is a solid bar symbol that moves to either side of a central line. The idea is to drive in a way that keeps the bar in the centre and away from the shaded/dotted areas on either side.
When driving smoothly, and thus efficiently, the bar stays near the centre of the indicator, shifting slightly right during gradual acceleration and slightly to the left when braking gently. During these conditions, the ambient meter behind the speed display glows a green colour to show optimum economical driving performance.
Under greater acceleration or when braking moderately, the bar in the MID shifts more towards either end of the scale, showing the use of more fuel, and the ambient meter glows a green/blue colour.
With aggressive acceleration, or sudden braking, the indicator bar will head to the right or left, deep into the shaded areas of the scale to show major fuel consumption and the ambient meter turns blue respectively.
In order to achieve the best mpg figures, the driver should aim to keep the bar in the centre, and the display glowing green as much as possible throughout each journey.
To help motivate Insight drivers during each journey, another display above the bar indicator grants rewards for more efficient driving. If performing well, small trees will ‘grow’ above the bar to show the driver’s eco-progress.
Also, by pressing the Info button on the steering wheel and scrolling through the MID displays, drivers can not only look at their average mpg of the current trip, but can also retrieve their average fuel economy of the last three journeys.
Once a journey is over, and the ignition is turned off, the black and white ‘Eco guide’ in the MID changes to an ‘eco score’ display. Now, the tree symbols at the top report on the driver’s performance during the last drive, while the bar and symbols at the bottom of the display show a lifetime score. This is shown in three ‘ranks’ with the fully grown tree and flower to the right of the bar showing the best score.
If the driver’s rank has improved since the last journey, a recognition symbol is also displayed, with wreathes and trophy symbols reflecting good progress. Conversely, if the driving style is worse, and the lifetime score and rank decreases, a more depressing recognition symbol of a withering plant is displayed.
Honda is aiming for people to think about the Eco Assist system as a Tamagotchi – those digital pets that took the world by storm in the late nineties. As with a Tamagotchi, the nicer you treat your car, the more it will reward you.
Official fuel consumption test procedures have been in use since the 1970s. EU Directive 80/1268/EEC describes the tests, which all new cars (on sale after 1 January 2001) have been required to take.
All tests are carried out in a laboratory on a rolling road (or chassis dynamometer) at an ambient temperature of 20°C to 30°C from a cold start, (ie, the engine has not run immediately beforehand).
Each test doesn’t actually measure the amount of fuel going into the engine. Fuel consumption testing is conducted by testing a measurement of CO2 emissions and air quality pollutant emissions, and a ‘carbon balance’ calculation determines the fuel consumption.
The test route is only 11km long. The VCA says this “is not dissimilar to UK average car journey length”. It is a completely flat route, without uphill or downhill sections, both of which would affect real world fuel economy.
The cars tested have to be run in and must have been driven for at least 1,800 miles (3,000 kilometres) before testing. There are two parts: an urban and an extra-urban cycle.
The Urban cycle test consists of a series of accelerations, steady speeds, decelerations and idling. Maximum speed is 31mph (50 km/h), average speed 12 mph (19 km/h). The distance covered is 2.5 miles (4 km).
The Extra-urban cycle test is conducted immediately following the urban cycle and consists of roughly half steady-speed driving and the remainder accelerations, decelerations, and some idling. Maximum speed is 75mph (120 km/h), average speed is 39 mph (63 km/h). The distance covered is 4.3 miles (7 km).
The combined figure is calculated using the urban and the extra-urban cycle. It is an average of the two parts of the test, weighted by the distances covered in each part.
In the acceleration elements of tests, the driver has 50 seconds to accelerate to 62mph. This is to allow for all types of vehicle, eg, buses/HGVs which might take that long to get to 62mph. Every vehicle has to follow an acceleration curve (speed against time).
No switchable additional equipment (air conditioning, wipers, head/sidelights, audio equipment, Sat Nav) is included or activated during the test. These would affect the fuel consumption of the engine.
“Because of the need to maintain strict comparability of results achieved by the standard tests, they cannot be fully representative of real-life driving conditions… The consumption achieved on the road will not necessarily accord with the official test results.” www.vca.gov.uk
While there were many considerations and factors that affected the exterior design, it was aerodynamics that most governed the shape and look of the Insight.
Making the car as slippery as possible exaggerates the already frugal hybrid technology on board the Insight, increasing fuel economy. So the design team set about creating a shape that had minimal drag.
The exterior design is similar to that of the FCX Clarity, but that likeness is closest when the two cars are viewed in profile. It’s clear that the rear sections of these two cars are almost identical in shape – and for good reason.
Firstly, the line from the centre of the roof to the top of the boot lid is at the optimum angle for controlling the flow of air off the top of the car, with minimum turbulence.
Also, the top half of the body tapers in towards the rear of the car, which also helps the air flow travel smoothly over the top. Stable air flow over this section helps the car pass through the air with minimal drag.
“We learnt a lot about aerodynamics from the first Insight,” says Mr Minowa, Creative Chief Designer.
“From the B-pillar back the two cars are very similar, but we couldn’t have radical optimisations like the covered wheels, for example, as this Insight had to have more appeal.”
Over the next few years Honda will also launch a sporty hybrid (based on the CR-Z), a Jazz Hybrid along with the Civic Hybrid.
