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Slashdot Asks: How Prepared Are You For an Earthquake?

AaronW Somewhat prepared (190 comments)

All of my bookshelves are strapped to the wall. My hot water heater has three straps (only 2 are required). Emergency rations are available plus I have my camping equipment and propane for my stove. Next to my bed I have an emergency radio that charges via USB, solar or a hand crank. I'm not terribly concerned about water though I keep several gallons of bottled water. I have a water purification system for camping but the main water supply is literally two blocks away from me though it's on the other side of the Hayward Fault. They just retrofitted the water pipes crossing the fault a few months ago right near my house. In an emergency there's always 50 gallons in my hot water tank. I also have a wrench handy for turning off the water and gas. I'm more worried about gas, especially given that we're supplied by PG&E. It took many years of complaining by my parents until they fixed a rather sizeable gas leak under their property. The only thing I'm missing is a generator.

I imagine I'll have a lot of stuff falling off of my shelves making a huge mess.

My house is only a few hundred feet from the Hayward fault. The fault goes right through one of the nearby apartment buildings. Many years ago the developers would conveniently relocate the fault to suit them. Our old city hall which was built on stilts was built on top of a mound that was pushed up between two traces of the Hayward Fault.

My house is bolted to its foundation and is only a single story so it will probably be OK though I might have some damage from my chimney. I also have earthquake insurance though it's quite expensive (around $4K/year).

2 days ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:Meh. the time limit is still there (174 comments)

The superchargers are not subsidized in any way by taxes. The cost of the electricity used is factored in to the price of the car itself for the 85KWh battery or is a $2000 option for the 60KWh battery car. The actual cost of the electricity is not much. If Tesla is paying $0.10/KWh then a full charge is $8.50. $2000 would cover a lot of charges. Since most charging is done at home overnight it ends up not costing Tesla much money at all. As they build out their solar the cost of the electricity drops even further. Tesla also paid back, with interest, their government loan. The $80K cars are being used to fund their development of $30K cars.

Tesla has agreements with the property owners for installing their superchargers in their parking lots and it's often in the property owner's interest since that means that someone with an expensive car will be stopping by there for half an hour or so to charge and will likely want to use the amenities in the area. Public funds are not used in any way.

about two weeks ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:Meh. the time limit is still there (174 comments)

Currently there are far more superchargers than hydrogen filling stations and they are expanding very rapidly. On top of that, there are tens of thousands of public charging stations at shopping centers, parking garages and elsewhere. Electricity is everywhere. A supercharger is estimated to cost under $200K. A hydrogen filling station cost a minimum of between 2 to 4 million to build and the cost of hydrogen will never be competitive with gasoline, especially if made from cracking water water.

The cost of a battery swapping station is still far less than the cost of a hydrogen filling station. Most of the time the only thing that is needed for the battery swap is electricity and periodic restocking of batteries, which may not be all that often since the cost of swapping includes swapping again for your original battery. For one thing, the hydrogen filling station will need to be manned when it's open for safety, the battery swap does not need that since it is fully automated. Second of all, the cost of a hydrogen filling station will be far higher. If hydrogen is not made on site then a LOT of trucks will be needed to transport the hydrogen since a truck can typically only carry enough hydrogen to fill around 200 vehicles due to the heavy high pressure tanks involved. Regular pipelines cannot transport hydrogen due to embrittlement and leaks. High pressure pumps are also required. The equipment to make hydrogen on-site is also very expensive, and if it is made from water then a tremendous amount of electricity is required. Most likely it would be made from natural gas through steam reforming which also releases CO2. It takes several times as much electricity to make hydrogen to power a single hydrogen fuel cell car as it does to power an EV. In fact, 20% of hydrogen's energy content is used just to compress it.

Furthermore, you will need far more filling stations since EVs typically do most of their charging at home. With hydrogen this is not really possible. The only time I need to use a supercharger is during long trips. I have no need for most of my driving which is within the range of the battery. I spend 5 seconds plugging in at night and 5 seconds unplugging in the morning. Superchargers are typically needed along long distance routes, not in every town like gas stations or hydrogen filling stations.

http://www.thenewatlantis.com/...
http://www.teslamotors.com/sup...

about two weeks ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:So there is a problem... (174 comments)

Tesla also uses waste heat from the inverter and electric motor. A gasoline powered car also gets less milage in very cold weather. Tesla loses 15-20% of the range in very cold climates which is not all that significant.

about two weeks ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:Meh. the time limit is still there (174 comments)

I see superchargers popping up all over the place. They're becoming quite common along the east and west coasts. They're not needed for in-town driving since most people charge at home. The battery swap will cost about the same as a full tank of gas and includes swapping your original fully-charged battery back on the return trip. Using the supercharger is free forever.

I've used the superchargers numerous times and they were not a major inconvenience. When I drove up to Lake Tahoe from the Bay Area I stopped at the one in Folsom. I went and grabbed a burger and by the time I was done eating and using the restroom the car was ready to go and it cost me nothing to use.

Every morning I start out with a full battery. It takes me 5 seconds to plug in at night and 5 to unplug in the morning. I spend far less time charging than I ever did waiting in line to fill up with gas at Costco. Besides, I don't have to stay with the car while it's charging. Usually there's other stuff to do within easy walking distance. In 30 minutes I get 170 miles of range. They're generally only needed on long trips, not for everyday driving since it's more convenient to charge overnight at home. Even charging at home I average over 50 miles of range per hour of charging (with a dedicated 80A 240V charger).

The chargers are popping up all over the place as can be seen on Tesla's interactive map: http://www.teslamotors.com/sup...

Better Place died because nobody wanted the EVs that they worked with. Their range was also quite limited and the Better Place setup was quite expensive. With the Tesla I have a choice. I can pay to fill up in 90 seconds or spend nothing and wait a while.

My last electricity bill for around 1500 miles of driving was $62.57 for 39 days, and I'll admit I tend to exceed the speed limit and accelerate hard, so I'm not taking it easy either. Next month I'm driving up to Seattle and it will cost me $0 in electricity.

about two weeks ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:To make it clear (174 comments)

The drive unit is a combination of the single electric motor, gear reduction, differential and inverter and axles. It's all a single unit that can be quickly replaced. As Elon stated in his last earnings call, most of the problems were due to some cables that were tucked up in there coming loose and making noise. Before finding out that that was the root cause they just replaced the drive unit because it could be done quickly. Now it turns out all they do is apply some zip ties to fix the problem. The car is fairly modular and should be fairly easy to work on, especially since there's no engine in the way of everything. Things like power steering, coolant pumps, AC, etc. are all easily accessible after removing the frunk plastic tub or the plastic panel under the front of the car.

When I have taken my Tesla in for a problem they don't fool around but try to address it as quickly as possible. All of the issues I've had with my car, an early model S, have been addressed by later versions of the car.

Here's a picture of the drive unit: http://arstechnica.com/cars/20...

about two weeks ago
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Tesla Removes Mileage Limits On Drive Unit Warranty Program

AaronW Re:So there is a problem... (174 comments)

Assuming that the car is plugged in to charge at night it will heat the battery to keep the temperature at an acceptable level.

about two weeks ago
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Silicon Valley Doesn't Have an Attitude Problem, OK?

AaronW Re:The problem is hipsterism, not engineer culture (262 comments)

I don't know about the NYC area but in Silicon Valley I'm constantly being contacted by companies even when my Linked In profile clearly says I'm not looking to move. My employer is looking for more people with those skills since we make a lot of embedded processors targeted at networking and the data center. There are a lot of companies that make hardware in the area looking for good software people. Skills like being able to work on the Linux kernel and device drivers are in demand.

about two weeks ago
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Silicon Valley Doesn't Have an Attitude Problem, OK?

AaronW Re:The problem is hipsterism, not engineer culture (262 comments)

While I think many of the programmers in my group could do many of these things most are not young. Also most of the positions we open are for more senior people since we need people who can do things like write compilers, kernel developers, bootloader developers, etc. who understand the details of CPU architecture. When I talk with young people getting a CS degree I tell them that there is a huge demand for people with these skills. Few software people have a good grasp of hardware.

about two weeks ago
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Ask Slashdot: Life Beyond the WRT54G Series?

AaronW Re:Mikrotik (427 comments)

I agree with you there. I have a Mikrotik router and while routeros is very powerful there can be a steep learning curve. I have a lot of complex QoS rules which it seems to handle well so my online backup software does not impact any other traffic. I also use a lot of its other features such as DHCP relaying between various subnets and some complex port forwarding rules and traffic shaping. Most consumer oriented routers also can't do BGP and MPLS either.

about three weeks ago
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Ask Slashdot: Life Beyond the WRT54G Series?

AaronW Re:Mikrotik (427 comments)

I had no problem adding a 5GHz card to mine, but the coverage wasn't very good.

about three weeks ago
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China Bans iPad, MacBook Pro, Other Apple Products For Government Use

AaronW Re:Seriously can you blame them (115 comments)

Having seen plenty of code from Asia, I'll take code from the United States any day. The worst code I have ever dealt with all came from China and Taiwan. The worst code I saw came from this Chinese company: http://www.zdnet.com/hack-in-t...

about three weeks ago
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35% of American Adults Have Debt 'In Collections'

AaronW Re:So! The game is rigged! (570 comments)

I actually have a credit card through Citibank and another through Discover. I have maintained the Citibank card since around 1990 (I got it my first year in college and it was my first credit card) and the Discover card for over 15 years. The reason it's basically a free ride for me is because of the fees they collect from the sellers. The credit cards are paid off automatically through electronic fund transfer from my credit union checking account (again, no fees). I have never had a credit card canceled on me and I maintained a credit rating of around 800 with no loans and never an outstanding balance.

You need to research the different cards that are available.

about a month ago
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35% of American Adults Have Debt 'In Collections'

AaronW Re:So! The game is rigged! (570 comments)

By paying off a credit card every month I am not paying any fee to use my money. In this case the seller is paying the fee and I collect on the benefits. On one card I earn cash back and on the other I earn airline miles which I have used to fly all over the country with very little out of pocket for the tickets (mostly various airline fees and taxes). I don't pay one cent for the use of my credit card. I don't pay interest or fees. In my case, the sellers are paying the credit card fees, not me. I'm basically getting all of the benefits at no cost to me being paid by the companies I purchase from.

The scam is when you end up paying fees to use a credit card or when you don't pay it off and pay obscene interest rates. I could see someone doing that on a rare occasion like an emergency, but it should be paid off as soon as possible. Carrying debt for the sake of carrying debt on a credit card is stupid. I have never done this and always had a very high credit score.

All of my regular banking is through my credit union where I do not pay any fees to use my money. I don't pay ATM fees at any other credit union (and they'll reimburse me for any). The more I hear about banking through the big banks the more disgusted I am.

about a month ago
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35% of American Adults Have Debt 'In Collections'

AaronW Re:So! The game is rigged! (570 comments)

There is nothing wrong with using credit and loans as long as they are used responsibly. All of my cars up until my latest one were paid with cash. When I could get a 2% interest loan for my latest car it made a lot more sense to get a loan than to pay cash. If I can earn more than 2% on my savings then I am ahead. That's easy to do today. In the case of my house I did everything I could to pay of the principal as fast as I could. I also use my credit card for most things but I always pay it off in full every month. That way I get all of the benefits and protections it offers and none of the downsides. While I may have a car loan I certainly do not feel that I am in debt, especially when my savings exceeds my debt and is earning more than the debt is costing me in interest. I could pay off the loan any time I want to but it is in my best interest not to.

about a month ago
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35% of American Adults Have Debt 'In Collections'

AaronW Re:So! The game is rigged! (570 comments)

I find that there are more benefits to using a credit card and paying it off every month than just plain cash. For one thing, I earn bonuses and have flown for free all over the country using them. Second of all, if there is a dispute it gives me far more leverage. Third, in a number of cases it offers me a better warranty. There is nothing inherently wrong with credit cards as long as they are used responsibly. I ALWAYS pay it off every month so I never pay any interest or fees to use it. It saves me from always hitting the ATM machine, many of which charge an obscene amount of money to use. I can get reimbursed for the fees through my credit union but it's always a pain to have to always enter in the amount of fees I pay for a transaction. I can also use my ATM card, but the protections on credit cards are far better than those of ATM cards. It's a lot easier to deal with someone getting my credit card number than if someone somehow steals my ATM card number and PIN, which has happened at a number of places in my area. One of the big grocery stores in my area had someone running a scam where they were stealing the ATM card numbers and PIN numbers and it's also happened at a number of gas stations and even ATM machines.

The few times I have had my credit card number stolen and used I never paid a cent in fees or anything else.

The credit score is based on credit. My score was quite high even though I never carried a balance and did not have any outstanding loans. Credit scores, sadly, do not look at savings. Years ago when I went to buy a house I had no problems getting a rather large loan at the time even though I had never had any other loan before in part due to my credit card usage because I always paid cash for my cars.

In time I eventually paid off my house. When I went to get my new car I ran the numbers and with the insanely low interest rates it was far more economical for me to get a loan for the car than to pay cash. Since the loan is at around 2% all I have to do is see if I can do better than 2% with my savings. If I can do that then I'm ahead and it makes more sense to get a loan.

Even though I have a lot of savings I use my credit card for most things. By paying it off every month I get all of the benefits without the downsides. Debt is not always bad. I could pay off my debt in an instant but it makes more economic sense not to as long as my savings is growing at a faster rate.

about a month ago
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Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

AaronW Re:More Range Needed (119 comments)

Usually the recharge times don't matter. I own a Tesla model S and sold my gas powered car. For most of my driving I just plug in at night and have the equivalent of a full tank every morning. It's only on long trips where the superchargers come in to play. I rarely bother with public charging stations since I don't need them. Now on long trips the superchargers come into the picture. In my last trip to Reno I stopped in Folsom to charge up. It took about 40 minutes during which time I got a nice lunch, took a bathroom break, etc while spending not a dime on fuel. Granted, more range is always better for long trips, but having to take a 30-40 minute break after several hours of driving is often a good thing.

The extra time spent waiting to charge during long trips is more than offset by the time not spent going to gas stations when most of my driving is under the range limits of the car. I typically spend 5 seconds plugging in at night and 5 seconds unplugging in the morning rather than several minutes at a gas station waiting in line and filling up.

about a month ago
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Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

AaronW Re:More Range Needed (119 comments)

There are plenty of car chargers out there like Chargepoint which basically use a RFID credit card. You wave the card in front of the charger to activate it and it bills your account for charging. They've had this for years.

about a month ago
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Sand-Based Anode Triples Lithium-Ion Battery Performance

AaronW Re:That said... (60 comments)

Google for the Leaf issues in hot climates like Arizona and Texas where some owners lost 40% of their capacity in two years. There's a reason why most EV manufacturers have active battery cooling.

about a month and a half ago
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My most recent energy-saving bulbs last ...

AaronW Re:LEDs (278 comments)

I picked up some 3-packs of 40 watt equivalent chandelier bulbs at Costco that work quite well. They seem brighter than the original incandescents though I did have one fail within a day which Costco let me exchange without question. They also dim just like the bulbs they replaced. They're only 4.8 watts instead of 40 watts. I put in 2 months or less even though other than the single failure I have not had any other LED bulb fail on me and I'm up to around 20 bulbs so far. I don't think I'll buy another incandescent or CFL ever again. I still have a lot of CFLs to use up though.

about a month and a half ago

Submissions

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3mm Inexpensive Chip Revolutionizes Electron Accelerators

AaronW AaronW writes  |  about a year ago

AaronW (33736) writes "Scientists and engineers at the US DOE SLAC National Accelerator Laboratory and Stanford University have discovered an advanced accelerator technology smaller than a grain of rice. It is currently accelerating electrons at 300 million volts per meter with a goal of achieving 1 billion EV per meter. It could do in 100 feet what the SLAC linear accelerator does in two miles and could achieve a million more electron pulses per second. This could lead to more compact accelerators and X-ray devices."
Link to Original Source
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Earth May Once Had Two Moons

AaronW AaronW writes  |  about 3 years ago

AaronW (33736) writes "According to a story at space.com, Earth may once have had two moons. The smaller moon, estimated to be 750 miles (1200km) wide and only 4% of the mass of the larger moon, crashed into the far side of the larger moon which caused the features we see today on the moon. The surface of the far side of the moon is quite different than the side facing the earth, having a different composition and a much rougher terrain."
Link to Original Source
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Moon Rock from Apollo 11 Sent Back Into Space

AaronW AaronW writes  |  more than 5 years ago

AaronW writes "According to this article at collectspace.com, a rock collected by Neil Armstrong during the Apollo 11 mission was quietly sent up to the ISS back in March. It was sent up in a special case to protect it with instructions given to the astronauts to not open it. Contamination isn't a huge issue since the rock sample had already been exposed to the air and was not that remarkable, resembling Hawaiian lava. It will be revealed tonight for a 40th anniversary celebration at the National Air and Space Museum in Washington DC."

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