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Comment: Re:homeowner fail (Score 2) 494

I have had the same experience with Comcast Business. The business service for me has been the exact opposite of their residential service. The business technical support's first response isn't "have you rebooted your PC" and usually the first level support person has been able to resolve everything. The few times they've had to come out they were prompt and resolved the problem, having had to replace the line from the pole a couple of times (apparently the squirrels like to chew on the cable).

Residential just plain sucks.

Comment: Re: And the almond trees die. (Score 1) 413

by AaronW (#49334139) Attached to: How 'Virtual Water' Can Help Ease California's Drought

When I grew up the water was handled by a private company, Citizens Utilities. The water was undrinkable and came out of the tap brown. The emergency water supply was from an old leaky tank up on a hillside that provided 3 minutes worth of water. Oh, and the water costs a fortune. The residents passed a bond measure to buy out Citizens Utilities, spending a fortune to do it. They had to rip out and replace the entire system when they switched to the county water system. The county water was much better and a lot less expensive. The county system also makes use of RO of brackish water to help supplement the water supply and makes an active effort to refill the underground aquifer where possible, though the last few years of drought have made that all but impossible to do. The county buys water and passes on the cost to the users.

Some things can be privatized just fine, others not so well. The problem becomes the monopolies involved and how they skimp on maintenance and do everything they can to maximize profits. We have this problem with PG&E. They have a horrible record of maintenance and even though most power is generated using natural gas, which is at record lows in terms of cost we have about the highest electricity rates in the country. It was the same thing when we had Citizens Utilities for water.

Comment: Re:I can see this working! (Score 1) 271

by AaronW (#49332309) Attached to: Ford's New Car Tech Prevents You From Accidentally Speeding

In my current car it can be difficult to tell what your speed is unless you look at the speedometer frequently. There is no engine noise to go by. Newer models of my car read the speed limit signs and give a warning if it is exceeded by a certain amount and the adaptive cruise control already takes into account the speed limit (though it allows you to exceed it as well). The new model already reads speed limit signs. If a car is very smooth and quiet it can be quite easy to speed without realizing it.

Comment: Re:Why no "skateboard" designs? (Score 1) 229

Wheel motors make no sense in most cases. They add a lot of unsprung weight and add more complexity. You need to provide flexible cables handling a LOT of current at high voltage, plus you have to deal with dirt, water, shock, vibration and other things you don't want to get into a motor. You also require an inverter for each motor. You're better off having the motors in the body of the car. There's not a lot you can do about the issues of unsprung weight. I had a long discussion with a friend of mine who helped design the Tesla drive train about this. The unsprung weight is a big issue and has a large negative effect on how the car handles. You typically want to minimize unsprung weight. Think of the effect of all of that additional weight going over bumps. You also can't provide the gearing you can for an in-body motor. Most EVs use gear reduction.

Comment: Re:Sad to see the Republicans always... (Score 4, Informative) 85

by AaronW (#49287325) Attached to: New Jersey Removes Legal Impediment To Direct Tesla Sales

Except now the problem isn't the small dealerships. It's the huge dealership conglomerates that are worth billions. The laws were created in order to prevent the likes of GM from competing directly with third-party dealerships. In the case of Tesla, there are no third-party dealerships with which to compete.

Also, with the Tesla model dealerships don't really work. Every car Tesla sells is made to order. There is no inventory sitting around at dealerships. The customer orders exactly what they want and it's made to order. This is very different than a traditional dealership where the dealer buys an inventory of cars then turns around to sell it to the customer.

Comment: Re:The answer has been known for over 10000 years. (Score 1) 286

by AaronW (#49270201) Attached to: Elon Musk Pledges To End "Range Anxiety" For Tesla Model S

If one looks at the average power generation an EV is more efficient than diesel. Where I live none of my power is generated from diesel and a fair amount comes from renewable sources (wind, geothermal, solar, etc). The percentage of renewable power is growing quickly in my area as well and most new power plants coming online are natural gas since it's cheaper than coal. The percentage of power in the US generated from coal is dropping rapidly.


The energy losses in electricity transmission are fairly low (estimated around 7%). The chargers are also fairly efficient (over 90%) and charging Li-Ion batteries is also quite efficient. Similarly, the inverters are also quite efficient (over 90% is typical) and the electric motor are also quite efficient (typically 80% or higher). There is minimal loss in the transmission compared to an ICE vehicle as well since there are only two gears (single speed, just a 9.73:1 gear reduction). At least in my Tesla, losses due to resistance are quite low due to the very short runs between the battery, inverter and motors and very heavy duty power buses. On top of that, a lot of energy is recovered from braking, unlike diesel vehicles.

There are other advantages as well. An EV is extremely smooth and quiet, unlike a diesel. It cost me a fraction the amount it cost per-mile compared to a diesel vehicle as well. My EV gets cleaner as time goes on whereas most vehicles emit more pollution as they age.

Another thing to consider is that many EV owners have also installed solar to help offset their energy use, further reducing CO2 emissions.

For urban delivery trucks electricity makes even more sense.


Comment: Re:Good job Mr. Musk... apk (Score 1) 286

by AaronW (#49269285) Attached to: Elon Musk Pledges To End "Range Anxiety" For Tesla Model S

Actually it's not 4x the price in the market the model S is in. It's actually fairly comparible and in some cases a bargain when compared to the other luxury cars it's competing against. Right now they have 28% margins on the model S. As for profitability Tesla is doing the right thing and is spending their money on growth which is exactly what they should be doing. They're not an old established company like GM or Ford so they have to spend a lot of money investing in the infrastructure they need for the future (i.e. the gigafactory, R&D for more models, superchargers, more manufacturing capability, etc.) Once they're out of the huge expansion phase then they should be profitable.

Comment: Re:Can't help but think of (Score 1) 286

by AaronW (#49269245) Attached to: Elon Musk Pledges To End "Range Anxiety" For Tesla Model S

I don't know of any electric that gets 35eMPG. My model S is rated at 89MPGe. A leaf is even better. Also, the model S is not a sports car but a sedan. And we buy them because it beats the hell out of driving a Prius (my previous car). Hell, an electric can go 30 miles using just the energy required to refine a gallon of gasoline.

Comment: Re:Predictive behavior and minor User Input (Score 1) 286

by AaronW (#49269207) Attached to: Elon Musk Pledges To End "Range Anxiety" For Tesla Model S

There's a web site I use that is pretty good at estimating range. It takes into account the destination, change in elevation, type of tires, speed, temperature and wind conditions. Last week when I had my annual service the loaner car I drove (A P85+) had beta software running on it. The GPS showed an estimate of how much battery would be used for the trip. I know they're working on better integrating the charging and battery support into the GPS.

You know you've landed gear-up when it takes full power to taxi.