Month: September 2006

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Charge for 5 minutes, drive 500 miles

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This CNN article discusses a company that’s working on a new type of energy storage technology designed for electric cars. If it works as it’s supposed to, it will charge up in five minutes and provide enough energy to drive 500 miles on about $9 worth of electricity.

Something about that doesn’t sit right with me, and after a bit of maths, I know why. Consider the following, and I will appreciate any advice necessary if I have somehow cocked up these equations.

  • Electricity costs around 5.5 pence per kilowatt-hour (kwh) in the UK.
  • $9, at today’s exchange rate, is £4.75.
  • £4.75 therefore buys us 86 kwh of electricity.
  • The technology claims that it can suck up this amount of electricity during a five minute charge.
  • 86 kwh in 5 minutes equates to 1,036 kwh in an hour, meaning that this technology requires a 1,036 kilowatt power supply.
  • That’s just over 1 megawatt.
  • At 240 volts (where, broadly, amps = watts divided by volts), a 1 megawatt supply requires 4,166 amps.
  • 4,166 amps is roughly 70 times that provided to a normal domestic premesis, assuming a 60 amp UK domestic supply.

I’m preparing to wield the big “BOLLOCKS” rubber stamp, but before I do, let’s run those figures again assuming that everything’s in the US, so that differences in cost and specification of electricity supply between the USA and the UK aren’t affecting the judgement:

  • Electricity costs around 4 cents per kilowatt-hour (kwh) in the USA.
  • £9 therefore buys us 225 kwh of electricity.
  • The technology claims that it can suck up this amount of electricity during a five minute charge.
  • 225 kwh in 5 minutes equates to 2,700 kwh in an hour, meaning that this technology requires a 2,700 kilowatt power supply.
  • That’s 2.7 megawatts.
  • At 110 volts (where, broadly, amps = watts divided by volts), a 2.7 megawatt supply requires 24,545 amps.
  • 24.545 amps is roughly 204 times that provided to a normal domestic premesis, assuming a 120 amp US domestic supply.

It’s REALLY bollocks then. *STAMP*

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Top Gear’s Hammond crashes jet car

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I know I’m a little late to the party on this one, but I’ve not had a chance up until now to comment on Hammond’s crash. This is terrible, terrible news, primarily because such an affable chap has encountered such serious misfortune, but also because it doesn’t bode very well for Top Gear one of the last few if not the last remaining television programmes that sticks two fingers up at political correctness and hippy handwringing. The Health and Safety fascists have been desperately looking for reasons to sanction Top Gear for ages, and this will give them more than enough excuse. If Hammond dies, then it will be the end of Top Gear for good, despite the fact that it’s one of the BBC’s most popular shows.

The show’s popularity speaks volumes about the general public and what they think about all this politically correct handwringing hippy nonsense that goes on these days. Every day we’re told by these sycophants which longstanding words are no longer acceptable and what we can and cannot do lest we offend some minority, somewhere. We also have loony organisations such as Transport 2000 basically telling us that we’ll all be better off if we regress by a century or two in terms of transport and that programmes like Top Gear are “irresponsible” and that it’s not what people want to see. Yet Top Gear, a programme that makes a point of NOT adhering to these liberal dictats, and that especially hates idiots like Transport 1700 (sic), is one of the most popular programmes on the BBC. Go figure.

It’s this sort of thing that makes it so good (from Wikipedia):

During the November 13, 2005 episode a news segment featuring BMW’s MINI Concept from the Tokyo Motor Show showcased what Richard Hammond quoted as a “quintessentially British” integrated tea set. Clarkson responded by mocking that they should build a car that is “quintessentially German.” He suggested turn signals that displayed Hitler salutes, “a sat-nav that only goes to Poland” in reference to the Nazi invasion of Poland that started WWII, “und ein fanbelt that will last a thousand years,” a reference to Adolf Hitler’s propaganda slogan of “the thousand-year Reich”.

If we can’t poke fun at the Germans, who can we poke fun at? Come on, lighten up.

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Wireless: Not the convenience utopia everyone thinks it is

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You know what? I fucking hate wireless networks. It seems that every single day of my life I’m somehow supporting or fixing a wireless network, whether that’s at home, in the office or for a broadband customer. Wireless simply isn’t the convenience utopia that it’s made out to be. It’s unreliable, unsecure and absolutely no substitute for a proper wired network, despite what some bedroom network consultant idiots I’ve overheard in the Institute of Directors claim.

At work I’m constantly being asked what the WEP key is, even though it’s the name of a reasonably popular children’s television programme which is hardly difficult to remember. Then as soon as a website doesn’t load or whatever, it’s immediately assumed that the wireless network has gone down and I get a phone call or a shout accross the office as if it’s somehow my fault.

At home I get friends coming round who decide that they want to check their e-mail or whatever and so ask if they can use my wireless. I give them the 26 character WEP key and of course this is a big old hassle for them to enter into their PCs (which of course they have to do twice on Windows machines) and there’s lots of huffing and sighing, as if it’s some fucking huge inconvenience for them to use my Internet connection for free.

Then there are the hotels which claim to offer a wireless network service but it actually transpires that all they’ve done is install a couple of crappy wireless access points here and there and haven’t actually checked that it’s usable in all parts of the establishment. The Crowne Pointe is a fine example of this. Luckily they also have wired connections in the rooms, but that of course meant that we had to drive all the way to Hyannis (some 50 miles away) yesterday to get a network cable, because the wired port is behind the dresser on the other side of the room.

Then you get the people who insist on having a wireless network, but that also want it to be 100% secure. It’s not going to happen. If you want a secure computer network, don’t connect a wireless access point to it. You must choose between the “convenience” of wireless and a secure network, you cannot have both, especially when you don’t want to invest in RADIUS servers, secure certificates, and all the other stuff that’s associated with WPA encryption; itself no guarantee of 100% security.

Don’t get me wrong, wireless does have its place, but by no means should it be considered to be an all-encompassing solution for network connectivity requirements. It’s limited, unreliable, unsecure, and a lot of the time just not worth the hassle. It’s been improving over time, and will continue to do so, but it’s not mission-critical just yet. Until it is, use it at your own risk, and if it goes wrong, use a fucking cable.