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Comment Re:will they "cost no more to" buy? (Score 1) 176

Was it only the panels or the inverters, rails, etc.? I got a 5 kW system (4.3 AC) with microinverters and the panels cost about 1,100 per kW and another 5,000 for the inverters, rails, conduit etc. Labor etc. was another 1,000/kW (rebate makes it much cheaper).

Comment Re:Population/Area has to be a factor (Score 2) 278

There are fewer than 1 million people in SF, but it's also relatively small. I think the big problems are the very hilly streets that plateau at the intersections and cars parked end-to-end along the sidewalk. Drivers make right turns (or left turns at one-ways) from a downhill at green lights without seeing if a pedestrian is on the crosswalk (this happens especially during high traffic periods); every corner is virtually blind.

That, and the taxi drivers are some of the most aggressive I've seen.

Comment If this takes off, my guesses on what will happen. (Score 1) 446

Because human nature for many lets me down more often than not, my thoughts on where this will go.

  • People will change their phone numbers (part of the terms for someone saying they know someone).
  • People may stop using Facebook, and Facebook may ban them.
  • The site will be flooded by mostly binary distributions of 5 star vs 1 star.
  • The founders will make a fortune, regardless of if it flops.
  • A whole new industry in law will develop around quick libel suits.

I'm gonna refer to the Han Solo quote on this one (and I'm not talking about the Kessel Run).

Comment Flowing water around the triple point. (Score 2) 260

Pretty interesting really, my first thought was that the pressure was too low, but the Martian atmospheric pressure is right near the triple point of water. For liquid water to be there the pressure must have gone up above the nominal 600 pascals to 611 or higher, and the temperature above 0 deg C.

Comment Re:Maybe Scott just wasn't listening that hard... (Score 1) 163

I read the book, but I'm wondering how much mass the dust has. Momentum is density*velocity, if you have a kilogram of dust moving at 100 meters per second, the momentum would be 100 newton-seconds, not a huge amount, but more than the very thin atmosphere of Mars.

Comment Re:The difference between an 'event' and a 'race' (Score 1) 142

Never said cyclists don't use less energy. They use less energy, but they use it terribly inefficiently. And no, nobody burns "excess calories that they would have already eaten". The reason you get hungry after exercise is because you're burning calories. If you start burning an excess of calories and never eat more to compensate, you will starve to death.

If you ride your bike an hour, you'll burn about 500 calories. If you drink two beers worth drinking, you'll consume 500 calories. The average person has a pretty large variance in caloric intake and an hour exercise isn't going to change the food distribution of the world. So it's not a stretch to say that extra food consumption from cycling isn't going to affect the environment at all, when comparing to moving a 1000 kg car with the 90 kg person inside it going the exact same distance with the goal of getting that person from point A to point B. Nor is a single person driving a car, I think we're in agreement on that. The cyclist commuter wins easily. Especially if you go back to the petrol and car supply chains like you did with cyclists food (after all, oil wells don't drill themselves, nor does gasoline refine itself, nor do cars spring magically from the earth...all of these require tremendous energy.

And of course it's risk of death per mile that matters, not per time or per number of trips. Are you going to quit your job and pick a job closer to your home when you switch to the bike too? You have the same destination as in the car, just a different mode of transportation. You have to do the same number of miles.

This would be true if all miles were the same, but they aren't because of hills. My 10 mile bike ride takes 45 minutes where it would take me 30 minutes in Florida. Plus, probability math would use a timescale, not a distance. More important considerations would be the road configuration, traffic per lane, clearance between the car lanes and bike lanes, and the blood alcohol content of the driver and cyclist. Apparently it's more dangerous in the UK than the US, our fatality rates are 1:2. Clearly the UK roads are more hazardous to cyclists than American (because I know that the Brits drive better than we do).

The average Briton cycles 53 miles a year. The average number of car miles is 8200 - 155 times more mileage. Looking at the same year's accident statistics, 801 people died in cars and 8232 were seriously injured. 110 cyclists died, 3222 seriously injured. That's 7,3 times more deaths and 2,6 times more serious injuries for cars... which go 155 times further. Even if you factor in 100% of pedestrian deaths to cars (and hey, are we forgetting that we still need goods hauled around?), they're only about half of the car casualties, so it doesn't even bring the numbers close too each other.

Sorry, bike nuts. Your mode of transportation is horrible for the environment and horribly dangerous per mile. So stop trying to make us all take part in your stupid hobby.

By the way, I'm not saying don't drive your car, I'm just calling BS on saying that cyclists are less efficient than cars when considering commuting. And it is more dangerous, but not extraordinarily so.

Comment Re:The difference between an 'event' and a 'race' (Score 1) 142

I live in a place where the city keeps trying all sorts of ridiculous ways to force people out of cars and onto bikes, such as spending small fortunes to shrink down roads and doing nothing particular with the space on the sides, putting up all sorts of obstacles in the road (such as constant turn lanes, alternating between left and right) to turn 3-4 lane roads into effective 2-lane roads, building new buildings without any parking, tearing down existing parking, etc. And among their reasons for trying to force people off of cars is "safety for cyclists". But even if they succeed at making their goal of forcing a dozen or two percent of the population to switch from cars to bikes, they're only going to increase the total number of transport deaths.

I think I know the Silicon Valley city of which you speak, if you are referring to the recent changes in the road where I live. Especially if said road has a hill that is over 10% grade in spots.

See this link on bike statistics, based on what it says it looks like the risk may be doubled (if 2% of the deaths are accounted for by 1% of the trips), but those could be misleading. I'm guessing the better metric is time on the bike, not miles traveled.

As others have noted, a person burns about 3000 joules extra per hour on a bike, and 100s of kilojoules per hour in a car, so it's a no-brainer that overall cyclists use less energy if you are only doing personal travel, regardless of the food transport and other factors (also consider cyclists are just burning excess calories they would have already eaten).

How much that compares to the overall carbon cycle? Hardly at all and most of the changes you discussed are symbolic.

But again, this thread is about a father and husband who died while riding, it's a sad day for that family and some of the comments on this thread are disappointing.

Comment Re:Cause of death (Score 1) 142

Cycling is sport that demands tremendous technical skill in addition to fitness and the tri guys usually treat the cycling portion of their sport as a necessary evil. (Ever notice how world class cyclists are in their mid-upper 30s and sometimes in to their early 40s? Well past the average male's peak athletic prime?)

I'd say about half the triathletes I know (I'm one of them) are stronger on the bike than the swim (I always assume everyone can run okay). The issue with triathletes is that they often ride their aerobars in places where they should be on the hoods.

I feel bad for the man's family, more than likely he just made a mistake.

Comment Re:About over-reactive police state, not genius (Score 1) 662

I have to agree with you here. I knew someone who blew up mailboxes with pipe bombs because it was fun (this was in rural Oklahoma). The cops at the time knew he was a bit of a trouble maker and they heard through the grapevine about him setting off pipebombs. They pulled him into the office, tricked him into confessing, made him buy a new mailbox, and told him if he did it again he would go to jail.

This kid should have gotten less than that, even if his intent was mischievous. Call him to the office, listen to him, agree it's a clock, get him to understand that we know it's a clock but it does kind of look like a bomb and we have to be careful with things like that. Tell him to leave it home next time, and if he does bring it in, send him home for the day. Handcuffs should not be a part of this.

In space, no one can hear you fart.