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Note that's a record for electric car acceleration. Top Fuel (burning nitromethane) is still way, way faster. still impressive. I wonder if they have to go looking for a jockey-sized driver to minimize weight.

This statement really irritates me. First of all, FCVs are clearly not the ultimate in environmentally sound automobiles. BEVs will always be cleaner than HFCVs. and hybrids are strictly better than a HFCV. There's nothing a Mirai does that a Prius doesn't do better, including g CO2/mile...

Why do you say that? So far, Prius has been "destroying" (5X?) the Chevy Volt in sales. Granted the cargo capacity in Prius is way better than in Volt. but it seems to me that even with the same or bigger cargo capacity, it wouldn't be destroying Prius. Any word on the MSRP of the PHEV...

I think you're overstating the aerodynamic inefficiency of a minivan. Modern minivans have a coefficient of drag around 0.30, which is similar to the coefficient of drag of a modern sedan. Minivans do have a greater cross section that they present to the wind, but so does Model X. Yeah, maybe...

I agree. Tesla has its hands full making Model 3, which a whole lot of people want really badly. I'm just saying that I am disappointed at Tesla's choice. I'm sure there are some that much prefer Model X the way it is. Oh well. My oldest kid is just turning 4, so I can wait years before I...

I think it's easier to find evidence of a good market for an expensive SUV than evidence of a good market for a CUV, no? Porsche Macan? Mercedes GLE? I'm not sure if I've ever seen those on the road.

Also, while I agree that minivans have not generally sold at high prices, full size SUVs certainly have. Escalade. QX80. It's unclear to me why the more-practical sliding door means the vehicle should be priced less than the less practical swing door, but I'll concede that vehicles with...

Ironic that we're talking about the "Pacifica", which was the poster child for a "Crossover Vehicle" failing to meet sales expectations. so now they're making the "Pacifica" into a minivan instead of crossover.

For a while, I had been thinking that it would be nice to get a Model X to replace my Model S. Then I could move guests around when they came to visit. It's more fun to keep my family in the same vehicle as the guest family on a trip to San Francisco, or Monterey, or wherever. and as my kids...

I still think that a BEV + HFC range extender is one of the sillier exercises. When 90% of your driving is from the battery, and you mostly want the range extender for convenience on long road trips and for peace of mind of easy refueling, I would think that not_very_common Hydrogen fueling...

yeah, so your numbers agree that a BEV running on US mix or on Natural gas (which are similar in carbon intensity at 550-600gCO2/kWh) emits around 240gCO2/mile while a Prius emits around 214gCO2/mile, right? I'll grant that your report shows that a Mirai running on SMR H2 is much better than I...

Well, if you assume that the max power is limited by the battery, then the difference between power to the wheels and max power tells you a lot about efficiency. The published curves would then indicate that the car's efficiency is constant from 40 mph to 70 mph, and that it only drops off after...

The motor isn't that much less efficient at 8000 RPM.. See this graph: First Dyno Video - Page 6 You could conceivably get more torque to the wheels with a transmission, but the tires are already near the grip limits and the car's low speed acceleration is generally satisfactory. :-) and...

Thanks AntronX, but I'm not that interested in the "average"; I'm interested in the marginal usage. If I drive to San Francisco and back, how much carbon have I emitted compared to not making the drive. From the looks of it, we're always using as much of the non-emitting power as we can. We...

When I plug my car in overnight in California, what is the carbon emissions of the energy that comes on line to provide energy to my batteries? One can look up what the carbon emissions per MWh are for California where I live. but using that to talk about my car's emissions are a little goofy...

Disagree. The absolute statement was warranted. :-) How much more efficient are you going to make solar cars? The electrical systems are already pretty efficient, so the main thing you need to do is reduce the wind resistance, and that's something auto makers have been working on for decades...

Yes, a 14,500 square foot home is probably energy intensive. 75 square meters of solar is extensive for most, but that's about the size of my array and mine doesn't even cover my electricity usage. His home is way bigger than mine, so I imagine his electricity usage is noticeably more than...

I imagine Arnold's flights between Santa Monica and Sacramento caused a lot of CO2 emissions and he probably has an energy intensive house. Rich people often have large carbon footprints (e.g., Al Gore). I'm not sure it's fair to judge them on an absolute scale as most things you do with your...

That's pretty cool. :-) except for the part where the vehicles have a tendency to crash.

Seems unfairly harsh to me. I thought he had an intelligent point when he was trying to get rid of gerrymandering in the state. I thought he had an intelligent point when he argued that teachers shouldn't get tenure after only 2 years of teaching. I thought he had an intelligent point when he...

:-) funny, but probably not. Some interstates have 500 m radius turns. At 700 mph, that's like 20g's. If your upper limit is 0.5g (which seems like rather a lot to me), and you stick to 1000 m radius'ed freeways, you'd only be able to go 160 mph or so.

Petersen was right that you could make huge returns by buying long on AXPW: wait for the stock to come close to getting delisted. buy a single share. wait for the reverse split. sell immediately. If you did that on both reverse splits, the way that they're rounding up, you could have had a...

To drive them where? To work and back with a stop at the store, no, it doesn't take any planning. or it takes less planning because you don't need to figure out when you're going to get gas. To drive them to the National Park in the next state over, yeah, that takes some changes. but I do...

For me the risk of explosion seems like one of the least of the issues with Hydrogen. It's a solvable problem: just make the steel thicker. They should be able to make Hydrogen tanks safer than gasoline tanks. They will never be able to make HFCVs more fuel efficient than BEVs, and they...

Perhaps fewer components, but not lower cost. and gasoline engines have had decades to work out their issues. Net-zero emissions is a lie in today's electricity market. If you have a surplus of electricity, you should put it on the grid so that the natural gas plant down the street doesn't need...

I disagree. If you're going to make a range extended BEV where you're using efficient battery power 90%+ of the time, and only using the range extender to be a convenient way to refuel while on a long distance trip, why would you make the range extender an expensive fuel cell that is far more...

A gearbox in a Model S could get you more low speed torque or a higher top speed. but it's not going to get you more power at 40-80 mph. At those speeds, you're limited by how much power you want to pull out of your battery. The electric motor is quite efficient at a wide range of RPMs...

Projected range has also always been worthless to me. The last 5 miles has too much random noise (was there a little hill? did the traffic cause me to slow down for a bit?), while the last 30 miles usually includes irrelevant data (huge hill, traffic light, etc.). or how about this: if I...

If you're getting 300 Wh/mile, then I would think you'd be getting the rated range. If the car says it used 55 kWh, but the range dropped from 240 to 13, it seems like something else happened to steal energy, like the car being on and in park for a while with the computers and air conditioner...

Read/Watch the report from CR. They said they could only drive it short distances, and they speculated the reason for this is the car thinking the door was open. They went on to say that they don't base reliability based on their experiences with the car, but rather from surveys, where...

Agreed. Well, I think the jury would find the driver to have the ultimate responsibility. but I do think most Americans would feel that the driver's expectation that the car would stop was not completely unreasonable. and of course owners think that autopilot is here: the website details...

and working 100% as designed was a failure. - - - Updated - - - incidentally, is it supposed to ignore stationary objects? Most luxury cars have cruise control that works just fine in stop and go traffic. Does Tesla's not work in that circumstance?

The computer's job was to recognize the speed of things in front of it. It failed to recognize a stationary car as something in front of it. It failed. I think the + vs. - is a different scenario. That would be me hitting the accelerator in my 2012 car hoping the car would know that I really...

I wonder if the car could somehow alert you to such an "ambiguous situation". I don't want my car whining at me all the time, but it would be nice if the car warned that "hey, I think I'm making the right choice, but I'm not 99% certain." While I agree that the OP's accident was "the...

Why are you doing this? to save emissions of CO2? Where does your electricity come from? EVs are nice because even if the source of your electricity is natural gas, your car still emits less CO2 per mile than a similar gasoline vehicle. ICEs are like 25% efficient. Natural gas power plants...

Sorry Doug, but I agree with kptesl. PowerWall should be its own forum. Energy/Environment/Policy is more about how to save our planet, not about a Tesla product. Incidentally, Doug, thanks for generally being a great administrator of this forum.

Well I did mention the efficiency difference in my post. but with it, I pointed out that you need more energy to lift a plane with 100 tons of batteries in it. Unlike a constant speed car on a freeway, a plane's energy usage depends heavily [sorry] on its weight. To carry 1000 kg more weight...

Elon is talking about how batteries might get to 400 Wh/kg in the next decade, but gasoline/avgas is like 13000 Wh/kg. A 757 on a cross country flight might carry 30 tons of fuel. The equivalent energy in batteries would be like 1000 tons of batteries. A 757 can carry about 60 tons worth of...

As a cyclist, I have a different perspective: I hate that some people feel like they can just walk across a traffic lane if they don't hear something coming. If you step in front of me when I'm pedaling at 25 mph, there's a real chance that we'll both wind up in the hospital. Road bikes...

Seems like we can figure this out... For an HFCV, Let's say .35 kWh of electricity per mile. That means we need .7 kWh of H2 on the vehicle. That means we need 1 kWh of H2 at the plant. That means you need about 1.35 kWh of biogas (assuming they use their own biogas to power the...

I imagine it's mostly CO2 and H20 with few pollutants. The idea might be worth looking into, and it's unclear to me that it's any worse than Hydrogen. I've always wondered why we're so focused on Hydrogen, since Hydrogen is generally a difficult molecule to store and transport. If your inputs...

The argument is that even if you can charge your 85 kWh battery quickly, the 500 kW load on the electric grid "guzzles so much electricity" that it's not "ecologically sound". That seems like a stretch to me. I mean sure, a fast turn-on of a 500 kW (or 1 MW?) load is an engineering challenge...

Well, L.A. might be a particularly poor example. I calculate that it uses some 27 billion cubic feet of water, but has only about 17 billion cubic feet of rainfall. but I get your point. In the Bay Area, a lot of our rain water flows into reservoirs. These reservoirs "charge" the ground...

That's like saying that we should use Hydrogen for power because it's the most abundant element in the universe. and to those that think that desalinization plants can just use renewable power, well anything can use renewable power and electricity is one of the more transportable commodities...

It hasn't rained much in the last couple weeks and it's getting warmer, so I just turned on my lawn sprinkers. Three days a week. which is what I'd be doing if the reservoirs were full. My 2yr old daughter takes a bath 3 days a week now. just like she always has. In fact, the only change to...

I dunno; I think it helps to remove one of the last barriers to going electric. Someone just said to me, "Oh I could never get a Tesla because I drive to Disneyland every couple of months". I explained to them that with a couple half hour stops they could get there without paying anything in...

All I can say is "Wow!" You use a lot of power in a given month. :-) 30 kWh per day is average for an American. Connecticut is more like 25 kWh per day while Arizona is more like 35 kWh per day. Do you know where all your power goes? Two Teslas that each get driven 250 miles per day? :-)

1. When your boss calls you back to work, you take the 2nd car because that's happening outside working hours and the 2nd car is home? Do most people have jobs where that happens? I'm thinking that kids or long commutes makes this difficult for a lot of people already. 2. Is it common that...

If a Leaf is a practical second family car, doesn't that mean that it is practical for a lot of people? Most people in the USA live in households with more than 1 car. Most Americans (75%?) live within 20 miles of their workplace. There is a high percentage of families that could use a Leaf...

ugh; that article is awful. "polar ice is thicker than ever"? on what planet? Here on Earth, while East Antarctica has added a little to its cap, it doesn't come close to offsetting the losses of ice from West Antarctica and from Greenland. and if they're talking about the Arctic Sea, well...