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Thomas Pedersen
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I have a 325d with the same engine, only double turbo (a small and a large working in parallel). It's not even once a month that I get above 3,500 rpm. Many days I don't even break 2,500 rpm. Pollution above 3,500 is a non-issue. If you spend more than a few seconds at those rpms, you're driving your diesel engine wrong! That said, there might still be a defeat device in there somewhere.
Prediction: More than half of the passengers of these vehicles will be people who would otherwise use public transport or bikes. The concept of having to install an app means that you first have to know that you have to install that app and learn to use it. That means: young people and/or people who already use a slew of public transport apps. Only two things can drag me out of the comfort of my own car (at least presently): Hassle finding a parking space and wanting to have more than one drink before going back home. Other than that, the mini-bus looks cool! Great for airport shuttle service. PS: the seats are shaped for young, fit bodies... I think they know already.
I think it's relevant to point out, regarding average gas mileage that the user has a great influence as well. I average 15-20% better gas mileage than my wife, despite driving faster, because I understand the physics of the driving and the combustion engine. Sticking to speed limits also helps (a lot). Or so I've been told ;-) And it's OK to maintain enough distance to the car in front to not have to brake all the time, when it reduces its speed a bit. I have a 4-cyl BMW 325d (the one with a small and a large turbo working in parallel) with, I suppose, an inflated NEDC rating. However, if I stick to the speed limits, drive in ECO PRO mode and avoid a greater fraction of city driving than in the standards, I can almost reach the advertised value. However, I can also make it use twice as much fuel. Easily! To me it's fair that fuel economy ratings reflect what a trained driver can achieve with predictive driving. It's obviously not OK to tweak all other parameters like car weight, taping over openings, tire pressure, and all those other tricks they play before they resort to outright fraud.
I haven't been to Toronto but if it's anything like in the US, I'm not surprised by the conclusions of the study. When I first visited the US, I was appalled by the noise level everywhere. From construction trucks sounding like they had no muffler, to clanging steel wheels (hint: air suspension works wonders with isolating the noise and not having the steel car work as a loudspeaker), to droning A/C's everywhere. The dishwasher sounded like it was tumbling the dishes, while the ones we bought in Europe at the time were marketed with noise level (around 45 dB at the time) as one of the main selling points. The buses had extremely loud engines with a horrendous straining sound. But I guess it was a little cheaper than getting noise down to a decent level...
I'd venture that 80 km/h (50 mph) top speed is outright dangerous... Why the sudden regression back to under-powered golf-cart capacity? Less power than a Nissan Leaf. About the same capacity in a vehicle way more expensive and with 2-3 times higher Wh/mile usage. I am seriously underwhelmed. And this is coming from a non-Tesla-fanboi, who usually defends German auto makers for their late entrance to the party.
GT's are nice, but have some drawbacks: - Not dual-fuel; no HFO capability - Failure-prone gearbox (direct propeller drive simple and efficient) - Expensive and difficult service (large-bore engines can close-out individual cylinders and can largely be serviced by inexpensive labor) - While the GT is compact, the waste heat recovery unit (WHRU/HRSG) is quite large - Steam turbine = more components to fail Large-bore diesels get ~50% efficiency, which would be hard to better significantly in a small CCGT configuration with tropical sea water.
When you are at the top and have the best-seller, you don't need to disrupt yourself - just follow the market. BYD, Proterra, et al could not make ordinary diesel buses and expect to compete with the established players. Therefore - or for other reasons - they create something new. MB has been able to make this all along, they just didn't have any reason to. Technically, converting a diesel bus into a battery-powered bus is at least an order of magnitude less difficult than converting and ICE car into a BEV (hint: space for batteries, and market requirement for range, vs. actual range driven between charges). The commercial side is a little less straight-forward, since development costs can be recouped over a number of vehicles two-three orders of magnitude less than battery powered cars. However, buses are often under political influence, so a city can specify that only battery buses need submit tenders, regardless of the CAPEX/OPEX split compared to diesel buses.
There is no space available to install equipment to utilize the exhaust impulse right out of the exhaust valve, which is why the effort is reduced to recover the kinetic energy as pressure ('gentle' slowdown) before the turbine of the turbo. A multi-cylinder marine diesel has an exhaust receiver with the express purpose of reducing the pulsating nature of the exhaust and turn it into a steady flow in order to increase the aerodynamic efficiency of the turbo charger (which has too much inertia to utilize the pressure pulses). Concerning sulfur content. Maybe you're right, but according to a refinery guy i heard, when I used to be in the 'utilize exhaust energy from marine diesels' business, it costs about the same to extract sulfur from heavy fuel oil (HFO) as it does to convert it to diesel + a pile of coke + a pile of elementary sulfur. And the latter combination has a much higher sales value. So right now, afaik, the strategy is to bunker HFO for ocean sailing and LGO (light gas oil - diesel) for near-shore sailing. But even without the sulfur in the exhaust, HFO has so much sticky, unburnt 'stuff' (all the accumulated crap from the oil field through the refinery) that clogging is a high risk below temperatures where anything (sulfuric acid or organic compounds) can condense. And, as refineries get more efficient in extracting all the valuable stuff, the remainder - HFO - gets worse. And the quality of the crude oil is also generally declining, because all the best oil was produced first. Note: Diesel (LGO) generally costs about twice as much as HFO
From the looks of it, this bike has at least two and probably three in-wheel motors. Should be quite the rocket when unloaded. Also, plenty of space for batteries under the cargo container. Good initiative. Although, biking in really cold weather is just no joy. It's fine, when the temperature is constant and you can dress for it. But stepping off the bike in 20°F and into a 68°F elevator will leave you sweating like the troops in Iraq! And if the stop is long enough, you could end up getting very cold when you come back to the bike. Factor in half an hour a day to go back for forgotten mittens...
I must say I question the motives of this request, since neither of the 'ideas' make any thermodynamic sense at all. TEG's have, what 1-3% efficiency (where the heat is lost at sink temperature), a factor of 10 lower steam generators. 'The kinetic energy of the exhaust gas'... Give me an F'in break! If the exhaust gas is moving at an unreasonable high speed of 30 m/s (100 ft/s), its kinetic energy is 292 J/kg, whereas the energy potential is 110,000 J/kg (by cooling 100 K to avoid sulphuric acid condensation and/or clogging from heavy fuel pollutants). And this kinetic energy could be 95% recovered by reducing its speed to 5.4 m/s (18 ft/s). Either some brainstorm was not filtered through someone who passes Thermodynamics 101, or they are pretending to do something about their emissions by throwing a hail Mary at 'some future development'.
In Phoenix and Houston it is probably correct that more CO2 would be saves by making the house (insulation + AC) more efficient, provided that the power comes from high-CO2 sources. However, I we are to do anything serious about climate change - and many other pollutants from energy generation - (nearly) all electricity production has to be switched to zero-emission sources within a couple of decades. That is why the transportation sector needs to electrify itself. Luckily, the power-hungry sun belt cities are also the easiest to switch to solar (and wind and nuclear), because of the concurrence of power production and demand. Also, here solar energy is fast becoming 'too cheap to meter'. Well, not quite, but prices are plummeting faster than most projected just a few years ago. Solar + cold (ice) storage for the A/C + batteries for lights, TV, etc. and you could practically go off-grid in those states (not that I recommend that). And you see clearly that a number of BEV's in the garage with a combined capacity of 2-300 kWh would dovetail quite nicely in this scenario. Making the A/C more efficient or installing more/better insulation will compete with the prospect of just installing more panels, with the incremental cost of adding another panel dropping daily. As much as I am personally in favor of energy efficiency, I'm just not sure it makes business sense in many cases with cheap, clean energy.
Very positive to see this kind of stream-lining and standardization of diesel-electric power trains and systems after a quite slow take-up in large parts of the bus industry. Should be a very short time now before the last diesel-only bus is sold for anything other than long-distance coaches.
Curious, 47% improvement is pretty darn close to exactly the improvement of both e-Golf and BMW i3 with the the same battery pack size...
When I'm pumping diesel, I have to stand there waiting in the 45° rain, because too many people were stupid enough to disconnect the nozzle before they drove off. With electrical 'fueling', I expect I can get back in the car and play games on my phone for 5-10 minutes, or go to the store, while leaving the car unattended, so I can drive 100-230 minutes more. Huge improvement!
There are some very, very good safety reasons to limit e-motor power to 250 W and cut-off speed to 15 mph/ 25 km/h. Mainly the safety of the other thousands of bike riders riding along side you: https://evolvetours.com/wp-content/uploads/2017/02/Biking-Copenhagen-Scandanavia.jpg Having the gear integrated into the drive unit is genious because it avoids the weight and complexity of rear wheel gears, whether an derailleur system (central motor) or planetary gear (usually with front wheel motor). This way both wheels become clean and easy to take on and off when you get a flat tyre. It also reduces the 'un-sprung' weight, in case of wheel dampers. 3.8:1 gear ratio is very respectable and should be plenty for everyone with up to 250 W assist.
400 mAh/g at 1 V is 400 Wh/kg, which is quite high. The voltage is really not a concern, unless you go to very low voltage, where several hundreds of batteries need to be connected serially to achieve proper voltage. Anyway, the voltage in the battery and motor supply is handled by a DC/DC converter. Too low voltage results in too high current, which necessitates heavy and expensive cables.
What are you smoking, mahonj? ;-) What customers do you think would like to have A4 120+60 TFSI stenciled on their boot?
Fewer places other than airports are better suited to BEV operation. They only drive <10% of the time and stay parked by the terminals plenty of time to charge the relatively small battery required for driving to a plane. Sorry, I'm not impressed by this news. Of course, Neste being a Finnish company, makes them more likely to choose this route...
I have always claimed this option would be economical, despite possible low utility ratio, because installation and power management costs drop to near zero when installed in a factory into a car that already has those components. I imagine the cost to the factory is counted in tens of dollars, if that when fully implemented.
FastEddie, 5 years is how long it normally takes one of the major German auto makers to set up a new platform and prepare everything for mass production, to churn out hundreds or thousands of fault-free units per day. Another reason for the delay is that they are concentrating their efforts, including the staff with the necessary BEV-skills, on the Golf-sized I.D. - the right move by VW, in my opinion.
What is the maximum regen power? I suppose it is also 16 kW, limited by the 333 A running through the wires and power converter..? It may take a few years but I definitely think this technology will percolate down to the Ford Focus class vehicles. Probably as an optional extra because these features appear to increase comfort almost as much as they improve fuel efficiency. With time, this technology would ideally motivate development of much less sophisticated ICEs with higher peak efficiency and lower component count (no more cylinder de-activation, VTG, etc.) and thus reduce the premium of a fuel-saving 48V system.
I agree with E-P. I think the 48V systems are going to be a Trojan Horse and enable gradually increasing electrification as it makes sense. And along the way, the ICE will get completely new tuning and modes of operation, such as burn-and-coast. When integrated with topographic maps and intelligence (oh, it's 5:30, and we're going the same direction as usual Mon-Fri, so program the ECU to minimize gasoline consumption for that particular route, taking into account on-line traffic information). I can't wait for cars to skip 1st gear entirely, because I loathe the sound they make in that gear. They rev too fast with no load, which makes for a very straining sound. Not like an engine under full power in 3rd or 4th gear, which is a quite pleasing sound - if you're into that sort of thing. There are loads of expensive equipment to potentially shed, when there's an e-motor to take care of all the challenging load modes. Variable valve timing, cylinder cut-off, variable turbine geometry, turbo chargers, etc. The Toyota hybrid system is complicated because their battery is too small. Ideally, there would be an e-motor with sufficient power and battery capacity to handle all driving in all but the highest gear. The ICE would only kick in from 40-50 mph or more. An ICE tuned for optimum efficiency at a narrow operating window (65-75 mph). The current PHEVs are mostly overly complicated, using highly advanced (expensive) stock engines. Once customers and car makers start to 'trust' the electrical components, they should be more inclined to simplify the ICEs again. And with that, gasoline cars could easily slash their effective gas consumption by a very large percentage - enough to make it less important whether BEVs take over entirely.
9% reduction is 90% short of what is really needed. The real-life health costs of NOx are actually quite high.
Wh/kg may be important for airplanes but Wh/litre is more important for most practical applications. Cars, cell phones, laptops etc. are all volumetrically limited concerning battery capacity. For BEV's a bit of extra weight is not welcome, per se, but most of the energy required to accelerate it is recovered during braking and thus not a deal breaker. But try finding more space for it, and you will struggle.
The highly complicated and spatially challenges battery of the eGolf beautifully illustrates the need for the MEB platform, and why the eGolf should be discontinued when the I.D. arrives. That said, VW, please go as far as feasible down the 48V route with gasoline-powered vehicles, preferably using the gearbox-mounted 10-15 kW e-motor. PS. I wonder why VW finds it necessary to use an additional Li-Ion battery to power the AC and lights for the limited number of seconds of engine-off-coasting. What is the maximum number of seconds you have ever coasted in your car? 5? 10? 20?