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"Their current hybrid buses are a joke. They spend about 5 seconds between stops on battery mode and then almost immediately start up their diesel engines on leaving each stop."

Getting a heavy vehicle moving from a stop is the hardest work the engine will do. Having the high torque of electric motors to do this (or even just help the engine by working together with it) is probably the highest impact point for reducing emissions. It will probably allow for design changes in the engine to improve efficiency too since it now has a narrower range to aim for. Since busses stop and start a great deal, they get a double-win by using regenerative braking to store the energy of slowing the massive bus for use on start.

So, not as cool as fully electric buses (which are rapidly rolling out in many areas as the make a great deal of economic sense, even without taking into account externalities like air quality and climate change) but an important stepping stone with some thought and engineering behind them.

I drive a classic Toyota Supra and agree that I don't want to see ICE-powered cars banned completely. Where the government screwed up was with diesels; other than higher CO2 per mile, petrol-powered cars are actually quite clean, and we have ways (at least theoretical) for dealing with CO2. We have no idea how to deal with diesel emissions - NO2 and particulate matter are a big question mark.

Hybrids are also very silly - while on one power source, the other is dead weight, which requires more energy to propel, dragging the efficiency down. They're a stopgap measure, nothing more. I agree that public transport needs to go pure-electric/zero-emission very soon - as soon as a bus pulls away, it spews a visible cloud of black diesel smoke, no matter how old it is or whether it's a hybrid.

A major problem I see is that many young people (myself included) are totally priced out of homeownership and therefore dependent on renting housing, meaning I cannot get access to a charging point at home. Even as a petrolhead, I would be interested in driving an electric car day to day or purely as a mode of transport, keeping my Supra for recreation only.

I checked the Supra's most recent MOT and it almost meets the 2008 (most recent) petrol emissions standards, with CO emissions off by a mere 0.2%. Larger, port-injected engines are clean enough to remain in use. Direct-injection petrols also suffer from higher NO2 emissions just like diesels, due to the higher combustion temperatures, so not only do these small engines use more fuel under boost (where they are most of the time), they produce worse emissions too.

> Hybrids are also very silly - while on one power source, the other is dead weight, which requires more energy to propel, dragging the efficiency down

Overall though the efficiency is higher. I get around 47 US MPG or 5l/100km in the city. Loaded with five people and on the highway I got 40.5 US MPG or 5.8l/100km.

"Hybrids are also very silly - while on one power source, the other is dead weight, which requires more energy to propel, dragging the efficiency down. They're a stopgap measure, nothing more."

Extra batteries are also a heavy load, whether full or empty. So it's not that simple a calculation. Also, the power sources do often work together, in various ways, so it's not always a question of two parallel systems, but rather considering it as a whole system working together, which in many case is better than either alone.

As battery prices fall, and energy densities rise, and fast charge solutions are rolled out widely, then pure EVs will push out hybrids, but they'll be around for a while and have already saved a whole lot of money (it surprises me how little people consider efficiency when thinking about moving civilization forward and making everyone wealthier) as well as toxic emissions and greenhouse gasses.

You're right in that it is indeed more complex, especially since hybrids use electric propulsion almost all the time. My point was that, while operating in pure battery-electric mode, the engine and fuel are nonfunctional and must be dragged around. An engine driving an electric generator is indeed more efficient than a pure ICE drivetrain, but versus the potential efficiency of a pure-electric power source, that's why I said 'dragging the efficiency down'.

I agree completely, hence my comment about them being a stopgap measure. Once pure-EVs are able to offer comparable range and charge time to a tank of fuel, hybrids will be consigned to history.

1) Difficult, but may be necessary; the health cost of particulates pollution is getting harder to ignore.

2) Not great but better than nothing. Buses spend a lot of time idling. Maybe we should bring back the trolleybus: https://en.wikipedia.org/wiki/List_of_trolleybus_systems_in_...

3) Sadly the market is going to have to be converted from the top down, because at the moment electric cars just have a higher sticker price. That leads into (4): this change will be a lot more popular if the "aspirational" car segment converts voluntarily first. Having a petrol performance car needs to become as socially unpopular as smoking.

In fact, maybe we need more extreme engine downsizing. Cap engine size and horsepower aggressively; large petrol domestic vehicles should be sluggish.

We'll have to address the commercial fleet as well, especially lorries.

The issue here is that, in most cases, while engine downsizing tends to provide some decrease in emissions, fuel consumption isn't all that much better.

If you look at the Fiat 0.9 Twinair 2 cyclinder engine real world consumption is somewhere between 35 and 40MPG despite a manufacturer claimed 68MPG. You cannot have a car with less than 80BHP either, it would be undriveable. In comparison, the VW EA888 2.0 turbo petrol engine (in the Golf GTI, Golf R, etc) has the same real-world consumption (because I drive one), yet can produce up to 300BHP at the top of the rev range if and when you need it. The reason for this is that the engine produces so much power and torque in the low-mid rev range compared to the 0.9 Twinair, the same rate of acceleration is possible without having to work the engine at all. It's not until you put the car into Race mode and use full open throttle that consumption drops below 30MPG to the mid 20s. What's more, in the case of automatic transmissions, gear ratios and software can be made to work the engine at low RPMs 99% of the time to decrease fuel consumption. This isn't possible with the 0.9 Twinair engine because it produces too little power at low revs.

> You cannot have a car with less than 80BHP either, it would be undriveable

Why say things like this, which are so easily contradicted? I used to drive a Peugeot 306 1.4 with a 75BHP engine that was perfectly adequate.

I'm sure that people like big heavy cars that accelerate quickly, but it's worth questioning how much you actually "need" one.

Because I also drive a VW Up! with a 59BHP engine (1.0 N/A) and I think the engine is too weak for the car.

The issue isn't the peak power, but the torque curve. Small, naturally aspirated engines have very poor torque curves, which means that you really have to rev the engine to get the rated power from it. In real driving, where you're between 2,000 and 4,000RPM most of the time, the engine only makes at most 40BHP (peak torque of a meagre 80lb-ft doesn't come in until 3,500RPM). This is fine for driving in built up areas, but it's really bad when you need to accelerate up-hill on an on-ramp to join a motorway or build up speed on dual carriageways where there are roundabouts every mile.

Cars have gotten a fair bit heftier since the days of the 306, largely due to advances in safety (crumple zones, airbags etc). Would you be willing to trade all that for better emissions?

My GF's VW Up! with a beefy 59 BHP is perfectly driveable.

Sure, I do find myself shifting more than on my car and it won't push past 100 mph but it can comfortably do 80 mph on the motorway.

It also gets about 60 mpg on regular use ( best i've measured is 70 mpg, beating VW's figures, IIRC; Mostly A roads and motorway within the speed limit)

1. This is essentially the same as the T Charge which comes into effect in October this year. Diesel taxis are exempt, which is a shame seeing as they are very high polluters, and also drive around all day long.

2. That would be nice, but 2020 is too soon to be realistic. Unless some of the newer busses have options to operate solely under battery with some modifications.

3. Gov. should absolutely invest in infrastructure.

4. Yes, this. It would be seen as favouring the rich, but there should be an exemption for petrol powered performance cars. Some of the finest examples of human engineering are found in supercars and it would be a shame for them to die out. Tesla is obviously a great example of an electric sports car, but there's something to be said for petrol sports cars. Of course, if all the car companies are working electric mass market cars, they'd probably stop working on petrol high end vehicles anyway.

Yeah, the thing to be said about petrol sports cars is that they have poor acceleration.

BTW there are all-electric busses available in the market. Stanford has a fleet of them from BYD, and there's also an American manufacturer, ProTerra. I've been stuck behind one of the BYD busses and was pleasantly surprised at how quickly it accelerated.

4. does not make any sense (especially considering your quite sensible 1-3) beyond: "I like it, therefore it should be so! Let's have the masses take care of the environment so we can have more fun on the expense of it."

I think if wasteful petrol performance cars are banned or at least prohibitively taxed it would open up a lot of innovation to get fun cars (or driving experiences real or virtual) to the market.

Don't get me wrong, I like the thrill of a performance car too, but I can't take this line of reasoning seriously if we are talking about tens of thousands of premature deaths a year of pollution in London alone let alone the much bigger environmental topic.

My concern with electric sports/performance cars is their weight over ICE cars. It ruins the characteristics of the car. You can add power to hide the weight of the car on a straight line, but in the corners the extra weight catches up to you fast. If anyone here has ever driven a Caterham or a Lotus they'll know exactly what I mean by this.

4. should make distinction between the one primarily used for recreation and one also used for e.g. commuting. Majority of cars are used purely for transportation and are expendable. Therefore it is reasonable to introduce a shift to electric because it has a higher impact. Track day cars are driven less miles, though slightly higher emission per mile, with smaller impact in total. It is as wasteful as operating a roller coaster in a Disneyland.

Most people don't care about what car they drive. For them driving a Prius is just fine. For petroheads driving a Prius is NOT fine. It feels as if Mac enthusiasts are forced to live forever with Windows XP, or Emacs/Vim users forced to write code with Notepad, or a mechanical keyboard user forced to live with a cheap membrane keyboard. It brings a huge disappointment to their life. For most people switching to a dull car means nothing, since they have been driving a dull car, which is not the case for them.

By the way, the more serious track day cars, without audio/AC/insurator, are painful and impossible to drive daily, in my personal experience. Especially the summer. One day I was dehydrated and could not shift properly.

> [Hybrid buses] spend about 5 seconds between stops on battery mode and then almost immediately start up their diesel engines on leaving each stop.

The point is that the diesel engines can always run at 1000-2000 rpm, which is the area of maximum fuel efficiency.