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Comment: Re:price and ROI of solar panels (Score 1) 131

by MrHops (#46950521) Attached to: Tesla Logged $713 Million In Revenue In Q1 and Built 7,535 Cars

I agree there unfortunately. I did the math a few years ago, during which time the electric price hasn't really risen substantially in the midwest. I basically figured that the cost of installing the PV panels would be recouped at about the same time that the panels reached about 30% of their original capacity... in other words by that point you'd be so close to replacement time that it was almost a wash. It just didn't make sense to me because when I also included costs of routine maintenance (you have to clean PV shingles or panels frequently to ensure maximum efficiency) it really was a net negative.

Now, if electricity prices were higher like in Australia then I could definitely see it making a lot more sense.

Where did you get these data? I can't even find any timetable for solar panels degrading to 30% rated capacity. The typical warranty is no worse than 80% of rated capacity after 25 years.

Doing a little math: Normal degradation is around .7% per year, so getting to 30% would take ln(.3)/ln(.993) or 171 years. Even at 2% per year it's roughly 60 years. All I can say is electricity must be pretty cheap where you live, if it takes 170 years for panels to pay off.

Comment: Re:One of my earliest multiuser gaming experiences (Score 1) 146

by MrHops (#46705035) Attached to: Born To RUN: Dartmouth Throwing BASIC a 50th B-Day Party

The biggest appeal was getting into the chat system. There, we could chat with what I assume were Darthmouth college students. "JOIN XYZ" I think was the command from the main menu.

There was this cool VT display of who was in the chat, so you could tell how many people were there. I used to chat with these people all the time. It was great for a precocious 13 year old who couldn't talk with his peers because his vocabulary and worldview was greatly expanded from theirs. How unfortunate that my social skills were so backward at the same time.

The details are a bit foggy, but I'm sure with some conversation with some of the same folks who used to chat there, I could dredge up those memories. Anyone remember chatting on that system?

Oh yes. I was a freshman in '80, and I spent a lot (too much?) time in Kiewit, playing the adventure game, writing programs in BASIC (and later BASIC7, which had a multi-threaded version if you can believe that) chatting on XYZ. Probably talked to you at one point.

BTW, it's 'Dartmouth'. I'm not fussy, but I'm sure there are alums who are.

Comment: Re:Efficient? (Score 1) 176

The average kwh cost in the US is about twelve cents, or $0.90 to $1.20 to go 25 miles.

PG&E has standard rate plans that vary from 11c/kWh (which is so little that you can't afford a refrigerator) to 30c/kWh. There are also special plans (time- and season-driven); one of them is specifically intended for charging EVs. In that plan, IIRC, the rate is about 5 c/kWh - but that is at night only. I do not recall what is the rate during the day. Utilities hide the actual rate tables. PG&E has a convenient calculator. I tried it with Tesla S60 and 60 miles per day. I got about $150/mo on plan EV-A.

60 miles per day * 30 = 1800 miles per month. If we convert this to a gas car, $150 pays for about 42 gallons of gas. This results in efficiency of 42.85 mpg. This not something to write home about. My own Prius does 52 mpg on flat land, and 45 mpg if you add climbing of the surrounding hills. If these calculations are correct, it is not efficient to use an EV even if you got it for free. At best it equals the hybrid that costs a third of the price of the EV.

I'm not sure I understand their math. A Tesla 60 gets at least 3 miles per kWh (, so your 60 mile day would take about 20 kWh. At 5 cents per kWh, that is $1/day, so about $30/month. To get a cost of $150/month would take electricity at $.25/kWh. At $.05/kWh, you end up getting more than 200 miles/gallon equivalent, and that's if gas is $3.57/gal. Around here (Bay area) it's closer to $3.80. Like I said, the math is squirrelly.

Comment: Re:Print shops? (Score 1) 166

by MrHops (#44362847) Attached to: Crowdsourced Finnish Copyright Initiative Meets Signature Requirement

So if I set up a print shop that prints and sells copies of recent bestsellers and sells them dirt cheap to bookstores that sell them at deep discounts to consumer's that's a misdemeanor? How about if I download copies of the latest movie releases, burn them to DVDs and ship them all over Europe?

Then you would no longer be a private citizen but would be engaging in business. I think that almost everyone agrees that anyone who does that for commercial gain should have the book thrown at them.

Better not copy "Lord of the Rings" then...

Comment: Re:Does this mean...? (Score 1) 181

by MrHops (#34408666) Attached to: Nook Color Rooted — Will B&N Embrace the Tablet?

All the harry dresden books, for example, decided to be in a bold fond in the version I downloaded. Makes purchasing them a LOT more worthwhile (which I ended up doing for the first few, until I decided to give up on the series, but that's another story).

I saw what you did there...

Comment: Re:Ah, the memories! And lessons, too. (Score 1) 305

by MrHops (#33266280) Attached to: Stupid Data Center Tricks

Ah, the memories! Here are some of the stories I've heard and or witnessed over the years.

  1. Buttons: Every couple years, IBM would hold an open house where anyone in the community could come in and get a tour of the facility (Kingston, NY). This was back in 1984, IIRC. PCs were just starting to make an impact at this time... big iron was king. We're talking about a huge raised-floor area with multiple mainframes, storage, tape drives... MANY millions of dollars per system. A few hundred users on a system was quite an accomplishment back then and these boxes could handle a thousand users. We were also in the midst of a huge test effort of the next release of VM/SP. I had come in that Sunday afternoon to get several tests done (death marches are no fun). All of a sudden the mainframe I was on crashed. Hard. I'd grown accustomed to this as we were at a point where we were "eating our own dog food"; the production system was running the latest build of the OS. But, an hour later and it was STILL down. Apparently, a tour guide had led a group to one of the operator consoles and a child could not resist pressing buttons. Back in those days, booting a mainframe meant "re-IPL" Initial Program Load. Unless the computer was REALLY messed up and wouldn't boot. Only then would someone re-IML the system. Initial Microcode Load. Guess which button the kid pressed? It left the system in such a wonky state that it had to be reloaded from tape. All the development work of that weekend was lost and had to be recreated and rebuilt. (It was a weekend and backups were only done on weekday nights.) It took us a week to get things back to normal.

Hey, I have a similar story from when I was working at Dartmouth College in the mid-80's. I was on third shift with two other guys, one who knew what he was doing, and one who was, uh, not fully technology-enabled.

For some reason, one night the latter person thought it would be a good idea to clean out the cabinet of our Honeywell mainframe. With a broom. A long-handled push broom.

This was on a weekend, when we normally do a full backup (onto good old 9-track tapes), reboot the system into protected mode, verify the system integrity, and go into multi-user mode. Well, we finished the backups, and tried to reboot. Nothing was working, and the diagnostics were wonky and pretty uninformative, and we (the useful co-worker and I) spent an hour or so trying to debug what was going on. It wasn't until we asked the third guy about the machine that he mentioned his cleaning. The boot switches for the IPL were on the door, and when he was in there cleaning, the broom handle toggled several of them, leaving the machine in its unusual state.

Needless to say, we asked him to avoid cleaning mainframes with brooms in the future.

Comment: Re:well.. (Score 1) 383

by MrHops (#33156346) Attached to: Steve Furber On Why Kids Are Turned Off To Computing Classes

FUSCHIA I really hope that was intentional.

Of course it was... it was a setup for another poster to come along and elevate the irony level via a similarly-constructed officious-seeming announcement in order to enhance the joke and provide, hopefully, additional chuckles among the fine readers of slashdot. Instead, by observing my typo, and failing to take the opportunity to craft a joke out of it in the same vein... why that's a complete waste of a setup. Can you help a brother out and at least continue the joke when the effort of a setup has been made?

This thread, however, is a fine example of depth-first self-flamage. For those of you who were in one of the schools that failed to properly teach computer science, observe and be edified.

Comment: Re:TiVo invented timeshifting? (Score 1) 490

by MrHops (#31292902) Attached to: The Sad History and (Possibly) Bright Future of TiVo

Yeah time-shifting is nothing new. It has existed ever since the Sony Umatic VCR released circa 1969. That VCR was too expensive, so Sony went back and created the Betamax (anc JVC copied it to create VHS) in 1975. DVR is not even the first digital recording method - that was miniDV and Digital VHS in the early 1990s. ----- People have been time-shifting for decades. All the DVR did was replace the magnetic tape storage with magnetic disk storage. Nothing revolutionary... it was an evolutionary change.

On the contrary! Using a disk to store data is completely revolutionary!

Sorry about that... couldn't help myself.

Machines certainly can solve problems, store information, correlate, and play games -- but not with pleasure. -- Leo Rosten