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Comment: Re:Most ambitious (Score 2) 132

by mrvan (#49256151) Attached to: Self-Driving Car Will Make Trip From San Francisco To New York City

Highway driving is also the most boring part of driving, and on longer trips often the largest part. City and local driving is kind of fun, you have to pay attention and hopefully you get some nice scenery and usually takes at most 30 minutes. Highways are just boring and can easily take 10+ hours. Fully automated highway driving (even requiring me to stay behind the wheel but letting me read, work or sleep until/unless an alarm goes off) would certainly be a killer feature.

I guess adaptive cruise control plus lane assist or whatever they call it comes close, so it should be possible to get it on the market soonish?

Comment: Re:Write-only code. (Score 1) 757

by mrvan (#49229065) Attached to: Was Linus Torvalds Right About C++ Being So Wrong?

There should be one-- and preferably only one --obvious way to do it.

So, tell me, should I prefer

borbs = []
for orn in orns:
    x = compute(orn)
    if x > 12:


borbs = [compute(orn) for orn in orns if compute(orn) > 12]

And please note that this is from someone who is actually Dutch, so it should be obvious to me, right?
(and it comes from someone loving and professionally using python for >10 year)

+ - Solar eclipse puts Europe's power supplies at risk

Submitted by mrvan
mrvan (973822) writes "An eclipse of the sun next month could disrupt Europe’s power supplies because so many countries now use solar energy, electricity system operators have warned. “The risk of incident cannot be completely ruled out,” the European Network Transmission System Operators for Electricity said on Monday, adding the eclipse on March 20 would be “an unprecedented test for Europe’s electricity system”.

Normally, it is generally cloudy in some parts or Europe while the sun shines in other parts: “Within 30 minutes the solar power production would decrease from 17.5 gigawatts to 6.2GW and then increase again up to 24.6GW. This means that within 30 minutes the system will have to adapt to a load change of -10GW to +15GW,” if it is a sunny day and all solar power stations were producing at full load. Solar power covered just 0.1 per cent of all the electricity produced in Europe from renewable energy sources around the time of the last large solar eclipse in Europe in 1999, according to the network, known as ENTSO-E. But since then solar power generation has soared to at least 10.5 per cent, as countries subsidise green power to meet EU renewable energy targets."

Comment: Re:Electric not the answer (Score 3, Informative) 212

by mrvan (#49099965) Attached to: The Best, and Worst, Places To Drive Your Electric Car

1500 Tesla's were sold in the Netherlands last year out of 400k in total, or around 0.4% [link]. However, in total electric+hybrid cars were about 4.3% of total [link]. So, while they are obviously not the majority, they are certainly not rare either. Amsterdam has almost 500 public charge locations [link] and in the center (where parking space is scarce) there are designated parking spaces for electric cars where they can charge, see e.g. this street view of what would be the closest parking spot to my house if I had an electric car. There are two taxi companies that use electric vehicles exclusively, which is good news since taxis have disproportionate impact on air pollution, one drives Nissan Leaf and the other Tesla. As far as I know they are not directly subsidized apart from general subsidies on electric cars, so they must be commercially viable.

All in all, electric cars are not some sort of pipe dream, they are out there and have small but growing market share, and infrastructure is growing with it. For each consumer a different tradeoff will be in order (e.g. I use my car a couple times every month so got a small gasoline car instead, while a friend commutes 50km every day so he got a Tesla). It still uses some government subsidy, but honestly, so do oil and traditional car makers.

Comment: Re:The Dangers of the World (Score 2) 784

by mrvan (#48831397) Attached to: Parents Investigated For Neglect For Letting Kids Walk Home Alone

There is a lot of things that I dislike the US* for, but as a European, I'm really grateful that they put their bodies on the line *twice* in the previous century to bail us out, even if both cases they would be completely right to say "you had it coming"**. So, a big "Thank you" to NotDrWho's parent and all his brothers-in-arms.

*) And the same holds for my country, and for Russia, and China, Israel, Egypt, Germany etc etc. Politics are messy
**) For WOI by entering in ridiculous alliances, letting minor incidents escalate, and thinking that War would be a great way to reinvigorate the continent; for WOII by not following the US'/predisent Wilson advise and instead enforcing draconian measures on Germany (looking at France), for electing and keeping in power a maniac (looking at Germany) and for trying to placate said maniac instead of doing something about it when it would have been easier (looking at all of us)

Comment: Re:IceWM == frosty (Score 1) 30

by mrvan (#48525579) Attached to: Using OwnCloud To Integrate Dropbox, Google Drive, and More In Gnome


Switched to xmonad a couple years ago, and I realized that all I ever need is (shortcuts for) multiple workspaces, terminal, and a program launcher.

(Interestingly, I actually much prefer the way floating windows are handled in xmonad in the rare occasions that they are useful (move with super+drag, resize with super+right-drag, what more do you need... plus those small and difficult to reach resize handles or title bars are a really stupid idea)

~$ sudo apt-get install gnome-desktop-environment
After this operation, 441 MB of additional disk space will be used.

non, merci!

Comment: Re:Cinnamon and MATE (Score 1) 89

by mrvan (#48499339) Attached to: Linux Mint 17.1 Cinnamon and MATE Editions Released

If you have an "obscene amount" of money, for a sufficiently obscene definition of obscene, you can add any feature you like to any open source project and get all the support you would even need, including a butler to click the buttons on the screen for you.

If you think that the price of a windows/adobe/matlab license qualifies an obscene amount of money, well, you're out of luck.

Comment: Re:combining micropayments with hefty sticker pric (Score 1) 473

by mrvan (#48409537) Attached to: Elite: Dangerous Dumps Offline Single-Player

Do you know whether it is pay-to-win (i.e. in-app purchases have a significant effect on gameplay) or mainly cosmetic (buying a paint job on your ship)?

If I pay real money for a game (>20 EUR) I expect it to be playable without subscription fees, microtransactions etc. For free or almost free games, I can understand either subscription OR microtransactions, but certainly not both...

Comment: Re:Ok but that's electricity, not energy (Score 4, Insightful) 488

by mrvan (#48367025) Attached to: Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

Heating and cooling is not symmetrical.

For one, it gets coldest during the night, when most people are in bed and blankets are a good tool to stay warm. It gets hottest in the middle of the day when most people are up and about (in countries without a siesta culture).

Also, isolating a house to keep in heat is much easier than isolating it to keep heat out, especially if you want to keep windows etc.

Third, warm clothing allows you to operate comfortably even if it is cold, a warm sweater means a room of around 18 celcius / 65 fahrenheit is comfortable. Stripping down is more difficult, but especially less acceptable in a business environment. Current business fashion originates in Northeastern Europe during the 'little ice age' of the 18th century, wearing a three piece suit with shirt, undershirt and tie is much more suited for 18/65 than for 25/77 degrees.

I live in Amsterdam and have the thermostat set to 19/66 degrees when I am at home, it cools down to something like 16 degrees during the night. I don't have A/C but in the summer the temperature easily goes up to 25/77 degrees in house, which is fine with light clothing. On hot summer days it can go up to 30/86 degrees, which is too hot to be comfortable for me, but that is quite rare.

Finally, Denmark might 'see' 15-30 degrees below zero once every century, but average low (night) temperature in January is more like -2. So, a delta of also around 15-20 degrees from room temperature.

Comment: Re:Home storage (Score 2) 488

by mrvan (#48366625) Attached to: Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

Avg US household use is in 2012 was 10,837 kWh per year, or about 29.7 hWh per day, so 50kWh is less than 2 days..

This is a story about Denmark, not the US. America has one of the highest per capita electricity uses in the world*. According to the wiki, Americans use almost three times more electicity than Danes, probably due to air conditioning and low energy prices (US is listed as .08-.17 $/kWh, Denmark 40.38)

Anecdotal evidence: I just checked my electricity consumption, which is around 4,000kWh for the past year, including a large TV and more computers than any sane 2 person household would need. According to an energy cost comparison site, the average 2+2 person household consumes 4,500 kWh per year.

So, assuming that an average Danish household consumes around 5,000 kWh per year = 13.7 kWh per day, that battery will last them 3 days.

*) Interestingly, Norway and Iceland are listed even higher - presumably because they have lots of hydropower and electric heating.

Comment: Re:Just moves a choke point (Score 1) 395

by mrvan (#48147597) Attached to: Battery Breakthrough: Researchers Claim 70% Charge In 2 Minutes, 20-Year Life

Aire de Berchem is Luxembourg is (according to Dutch wikipedia) the busiest gas station in the world (mainly because Luxembourg has the cheapest gas in the region and it is on a number of busy roads). It pumps 850.000 liters per day, enough to fill up 17000 cars*. If every car needs 70% of 85KWh, this requirs 85k * .7 * 17k = 1GWh per day. If they can spread perfectly over the day, it means they need a 50MW power plant, which I guess is not too far out there. This will probably require some impressive capacitator / battery setup to get enough peak power though, no clue if something like that is feasible.

(the total amount of energy in 850k liters of gasoline is 42.4 MJ/kg * 0.77 kg/L * 850kL = 27 TJ = 7.5GWh. So it seems that the total efficiency of electric cars is about 8 times higher, assuming equal range, which is probably false. But a factor 5 might be around right...?)

*) the wiki mentions it's 80% diesel, and while diesel cars are pretty common here, I would assume that means that the majority of liters goes to trucks. Now suppose your Tesla truck with 500KWh needs to charge in 5 minutes....

Comment: Re:Wow (Score 1) 134

by mrvan (#48080717) Attached to: Google's Security Guards Are Now Officially Google Employees

Our cleaning is outsourced and the cleaners generally have little command of the local language. I know most of them by now, however, and have a little chat when I can. I leave my wallet and phone on my table if I go grab a coffee to allow them to clean my office (I work late a lot of times). Nothing untoward ever happened and I've not heard any of my colleagues complain.

Who goeth a-borrowing goeth a-sorrowing. -- Thomas Tusser