Toyota Prius

rosie2

Regarding zero-emissions, the Prius is by far the cleanest car on the market -
Taking into account all kinds of exhaust emissions (amongst those equipped with an internal combusion engine). While CO2 emissions rival small cars, NOx and HC emissions are lower than any other petrol car on the road today. Particle emissions, a great inconvenience of diesel engines, are reduced to ZERO.

unkel

greglo23 wrote:

do a little research before you scoff. http://tinyurl.com/lv7w7

If you're seriously believing that you can travel forever without using any petrol, it's time for some basic physics lessons for ya

Hint: apply the first law of thermal dynamics in processes that are less than 100% efficient

maidhc

rosie2 wrote:

Regarding zero-emissions, the Prius is by far the cleanest car on the market -
Taking into account all kinds of exhaust emissions (amongst those equipped with an internal combusion engine). While CO2 emissions rival small cars, NOx and HC emissions are lower than any other petrol car on the road today. Particle emissions, a great inconvenience of diesel engines, are reduced to ZERO.

A lot of diesels, in particular the HDis are now being fitted with diesel particulate filters, which reduce particualtes by about 60% (although require a expenasive change at 70k). But at the end of the day, I think common consensus is that a prius uses up more of mother earths resources than a small diesel, or even a small car in general.

unkel

maidhc wrote:

A lot of diesels, in particular the HDis are now being fitted with diesel particulate filters, which reduce particualtes by about 60% (although require a expenasive change at 70k)

They were the first generation of particulate filters. Other manufacturers, like BMW, now fit Euro IV second generation DPFs as standard on most diesels that reduce particulates by nearly 100% and are maintenance free

maidhc wrote:

But at the end of the day, I think common consensus is that a prius uses up more of mother earths resources than a small diesel, or even a small car in general.

I agree unless of course one can run a prius forever without a drop of petrol

Anan1

eoin_s wrote:

Once you brake occasionally, you should be OK!

Please tell me you're joking?

maidhc

unkel wrote:

They were the first generation of particulate filters. Other manufacturers, like BMW, now fit Euro IV second generation DPFs as standard on most diesels that reduce particulates by nearly 100% and are maintenance free

All the better

Blut

I have to say, I'm not too impressed with the Prius. It looks like a slightly uglier Nissan Primera and at 40-50MPG its only about as economical as many smallish (VW polo sized) cars.

Eoin

Anan1 wrote:

Please tell me you're joking?

Of course I was - I just don't like to use the smileys all the time.

ninty9er

The prius batteries do not absorb power from the petrol engine, the batteries are charged by the kinetick energy of the car. Braking accelerating movement of the wheels etc... look up any junior cert science book. I'm sure there'll be an explantion of kinetic energy there for you.

Trust me i know 2 people that have them

maidhc

ninty9er wrote:

Braking accelerating movement of the wheels etc... look up any junior cert science book. I'm sure there'll be an explantion of kinetic energy there for you.

Aside from the regenerative braking which is essentially capturing energy which would otherwise be dissipated, the batteries have to be charged by the petrol engine...

Ratchet

unkel wrote:

Beware! The Prius doesn't achieve anywhere near the official MPG. In fact it struggles to get 45 mpg, way worse than a modern diesel of similar size

echo this


ugly car designed to safe our environment and have lower running cost

instead we end up with car which
-can only be serviced by toyota dealer
-is far from ultra economical
(for the price)
-leaves set of big f3cking batteries every 5 years for next generation to recycle.

nice one

unkel

ninty9er wrote:

The prius batteries do not absorb power from the petrol engine, the batteries are charged by the kinetick energy of the car. Braking accelerating movement of the wheels etc... look up any junior cert science book. I'm sure there'll be an explantion of kinetic energy there for you.

Trust me i know 2 people that have them

This is unreal :eek:

I'll try and explain based on my minimal technical knowledge. Here goes the theory bit:

According to the first law of thermal dynamics, energy is conserved in a closed system. A car on a hill of a certain height has a certain level of potential energy. When driving down the hill, the potential energy is converted into kinetic energy. Kinetic energy is maximised at the bottom of the hill and is sufficient to drive the car up another hill of equal height (kinetic energy converting back into potential energy)

Now in practice this does not work for a variety of reasons. Here's a few:

1. In practice there is air creating resistance for the car to move. The above example is in a vacuum so energy is lost
2. In practice there is rolling resistance of the tyres against the road so energy is lost
3. In practice the conversion from kinetic energy using regenerative braking and storing the energy in the form of electricity in the batteries is far from 100% efficient
4. In practice, the conversion of electricity into kinetic energy by the use of the electromotor is far from 100% efficient

Hope that helps

ninty9er

OKAY. there is energy lost and generated, but if the car kept storing energy it would eventually just explode...well u get my drift, u end up with full batteries the whole time. the point is that there will come a point when you use the petrol engine to power the wheels, causing more energy to pass into the vatteries than is passing out and the cycle continues.

Have you driven one.. been on a long journey in one... I have. They are not thirsty and are ultra quiet when the engine knocks off at 50 kph

Anan1

ninty9er wrote:

The prius batteries do not absorb power from the petrol engine, the batteries are charged by the kinetick energy of the car. Braking accelerating movement of the wheels etc... look up any junior cert science book. I'm sure there'll be an explantion of kinetic energy there for you.

Trust me i know 2 people that have them

This is both patronising and factually incorrect. As has been said before, the only time that the batteries are charged by the kinetic energy of the car is under braking. Although this energy would otherwise be lost, it was nonetheless originally provided by the petrol engine. During steady-speed driving, the battery is charged by the petrol engine. To say that no petrol is used below 50kp/h is simply ridiculous - the car is petrol-powered.

knifey_spoonie

I have seen no clear evidence that a prius needs a set of batteeries every 5 years/60k miles.Yet this seems to be the first thing people say when ever the prius comes up in this forum.

Yes the engine will sometimes provide power to recharge the batteries usualy when the car is idleing.The engine will cut in every 5-10 minutes so the batteries dont become fully discharged.

Ratchet

http://carpoint.ninemsn.com.au/car-news/DesktopDefault.aspx?tabID=500648&ArticleID=5487&R=ce5487

unkel

maidhc wrote:

All the better

Indeed. Looks like diesel is (or should be) king for the short to medium term

Fair play to the likes of Toyota and Honda for bringing mass-manufactured petrol / electric hybrids to the market. They're bearing huge losses on every single one of them sold, but it simply is too little too late in terms of (environmental) improvement

Both car manufacturers made a huge mistake in not copping on to modern diesel technology until very recently and are desperately trying to get their act together now, with moderate success

I can only see a place for the hybrids in these realms today depending on government fiscal policy. As mentioned, the Royal Emperor of London (Heil Ken!) declared no congestion charge is due for a hybrid. We have our own VRT reduction for hybrids

A bit of a different story in the US where of course anyone buying a hybrid instead of a supersized petrol SUV would contribute to saving the planet