Dan's Data letters #154
Publication date: 15-Nov-2005.Last modified 03-Dec-2011.
Try leaving the fridge door open
I've been trying to save money in the house by not having the AC on as much, but this invariably has me and all the roommates keeping their ceiling fans running all the time.
I sit staring at this fan being spun non-stop and wonder - how much juice is it using?
Is it really worth this discomfort for the amount I might (or might not) be saving?
Brandon
Answer:
Ceiling-fan power consumption depends on the kind of fan and what speed it's running at, but a reasonable middle-of-the-road
estimate is about 40 watts.
This, by the way, is a lot more power than is actually needed to do this much work. The shaded-pole motors that ceiling fans use are hideously inefficient, as are their simple flat blades. But flat blades are cheap (and can be very nifty), and so are shaded pole motors, and you can control the speed of a shaded-pole motor with a simple light dimmer, so they're still in use.
Air conditioning is much more efficient at pumping heat than ceiling fans are at moving air, but even taking that into account, air conditioning needs a lot more power than fans. A quite small window air conditioner will still draw 1400 watts; it's easy to find units that draw two or three thousand watts.
So unless you're paying an awful lot for power, a few ceiling fans shouldn't dent your budget. If, for the sake of argument, you're paying 10 cents per kilowatt-hour, four fans totalling 200 watts, running all day and all night, will only cost you 48 cents a day. A 2.5kW air conditioner running constantly, though, will cost six bucks a day.
Air conditioners are a big number in power-company demand calculations. In winter, people use various technologies to keep warm, and electricity is convenient but not usually very price-competitive, so many people only use it if they have to. Gas, oil or wood heating (or just wearing more layers of clothes...) don't strain the power grid. In summer, though, air conditioning's far and away the most popular cooling technology (the only real alternative is swamp coolers, which are cheap to run but can't cool air as much, encourage mould and rust, and don't work at all when it's humid), so suddenly every household on the grid averages another kilowatt or so.
Why cesium batteries aren't too popular
We received some 9V lithium batteries from Singapore. One of the cartons had burnt batteries in it. The supplier confirmed that he despatched the batteries in good condition - what do you think happened in transit?
Manish
Answer:
Lithium
primary batteries (the
non-rechargeable kind, as opposed to lithium-ion rechargeables) contain a metallic
lithium anode. Lithium is a very reactive metal; it'll catch fire if you drop it
into water, and may actually ignite spontaneously in air if it's humid enough. You
don't want to hold it in your hand.
For this reason, physical abuse can make lithium batteries catch fire. They'll also burn if they just get hot enough - lithium's melting point is only 180 degrees Celsius - and one burning battery in a box can set off the others.
The batteries contain safety devices to disconnect an electrode if they're short-circuited (which can easily make them hot enough to burn), but sometimes those devices don't work properly.
Damage from fire can make it hard to figure out exactly where the problem started, but if the batteries were packed properly (not just jumbled up in a box, and not with metal objects near the terminals), my guess would be that one or more of them was defective, or they got really hot in transit (sunlight wouldn't do it, but some genius might have put the box next to an engine exhaust or something). Or they suffered physical damage - for instance, the box being stabbed by a forklift.
From the makers of Gasoline Powder!
After your extensive look at metal's rusting, I was intrigued to know your stance on oil/fuel additives for cars?
I have used an oil additive in the past called "Bi-Tron" (see here; there are many other pages about it on the Web). It has served me well, and once allowed me to drive my XF Falcon about 20km with the oil pump broken. Well, I can't be sure if Bi-Tron provided this or I was just lucky.
But myself and many friends have sworn by this stuff - what's your take on it?
Benn
Answer:
Generally speaking, oil additives whose manufacturers make grand claims about economy, power and/or engine protection
are worthless at best and actively harmful at worst.
All-liquid additives are likely to be harmless, provided they don't manage to greatly change the viscosity of the oil or dissolve tubing or something. Additives with suspended solids (graphite, PTFE, fairy dust) are the ones that sometimes kill engines, when the solids cake up in exactly the way that engine lubricant is never meant to do.
As with get-rich-quick schemes and psychics, this is one of those situations where you can point to a string of more or less famously fraudulent products in a particular category, but there's always something new and amazing that hasn't been specifically debunked yet. And which, in the case of oil additives, might not even be chemically identical to, or sold by the same shysters who sold, one of the older ones.
So it's impossible to say that all of these concoctions are useless. But it's the way to bet. Simple single-function additives, like stuff you dump in your fuel to clean your engine's injectors, can work. But that's only for suitably small values of "can". Most if not all of these concoctions, definitely including injector cleaners, have been made obsolete by the additives that've been mixed into all brand-name fuel at the refinery, for many years now.
A standard patent-medicine-show demonstration of the amazingness of oil additives is an engine on a test stand, running peacefully, with the additive in its oil. Then, shock, horror - the salesman pulls the sump plug, and all of the oil drains out! And the engine keeps running! And then the phone number to order the stuff starts flashing on your TV screen!
The secret to this trick is that most engines, especially nice old low-performance ones where none of the parts fit together too tightly (see also: AK-47, RPG-7), will run for some time without oil. It's really bad for them, and durability varies from engine to engine, and you can't expect to rev any engine hard for a few minutes without oil and then be able to stop and start it again without replacing most of the moving parts. But this sort of thing still isn't nearly as miraculous as many people think.
Keep an old rattly engine moving without oil and it may not seize for a very surprisingly long time - it'll just wear very rapidly. Perhaps what eventually stops it will be the loss of all compression, or explosive and/or fiery failure of some other component thanks to the increasingly spectacular longwave infrared output of the high-friction engine block, or something.
High-performance engines will seize in short order if deprived of lubricant (ask any dedicated sports-bike rider...), and the jury's still out on whether there's something spooky about the ability of canary-yellow 1974 Toyota Corona station wagons to run apparently indefinitely without oil, or water, or fuel for that matter. But none of this supports the claims of the oil-additive salesmen.
Not him again
I'm from the States, but I thought the Guardian was a respectable paper?
Also, does the rest of the English speaking world often use the phrase "wrong maths"?
Jared
Answer:
Newspaper science reporting sucks - though The Guardian is actually now something of a candle in the dark, thanks
to Ben Goldacre. I hope he does a column on Blacklight
Power.
Randell Mills and his "hydrino" theory have been around for quite a while - I mention them in this column. Randell's had another blip of popularity recently, but it's been more than nine years since the publication of Mills' magnificently titled book, and the Web site for the company under its current name goes back to the start of '98.
And yet, astoundingly, still nothing.
Randy displays various signs of crankitude, including using the fact that his exciting "chemical process" is patented as if it implied value. As I've mentioned on previous occasions, I could get myself a patent for a machine that allegedly makes automobiles out of dog turds; it's not the patent office's job to make sure patented things actually work. The Blacklight patent only proves that the examiner didn't decide to refuse it on the grounds that it was a perpetual motion machine (which it isn't, though it's arguably a way in which you could drive such a machine).
Regarding "wrong maths" - it's a bit clumsy, but headline writers have a difficult job.
First, drive Rolls into swimming pool...
I'm not sure if you've already come across this, but it looks like quite useful gadget if you ever get stuck in a car that's sinking into the ocean.
It's a key-ring sized device that can apparently cut through seat belts, and uses a spring-loaded steel point to break through car side windows.
I'm looking at buying one, but have already brought a Photon 3, and some other gadgets for my key-rings, and I'm not sure if it'll be worth it. And their international shipping looks a little bare, with only a link to some Spanish company. Are these sorts of things distributed here in Australia?
Michael
Answer:
The ResQMe looks as if it works, but it's far from being the only product
in this market sector. It may (or may not...) be the smallest such product, which is a good thing if it means
you actually keep it with you all the time, but which might also mean you fumble it if you have to use it.
Probably the best known of the "full size" gadgets is the LifeHammer, and I think it, or some similar gadget, should be easy enough to find in Australia.
(A reader's now pointed out that the ResQMe and the LifeHammer actually seem to be made by the same company.)
There are a fair few pocket knives with both functions, as well, like this one (expensive, and illegal in Australia), and this one (cheaper, legal).
If you want the press-click glass-breaking function by itself, I think an "automatic" centre punch (from any half-decent hardware store) will do the job nicely, in a very small package. It works the same way as the ResQMe for that. Plus, you can use it as a centre punch!
More "relevant" ads
There is "Vibrant Media" text link advertising in this TweakNews review.
As I looked at the review I moused over the "Logitech" text linked word to see:
Logitech Mx1000 Legal Help
If you have purchased a Logitech Mx1000 mouse fill in this form to have a lawyer help you evaluate your case.
www.lawyersandsettlements.comI bet Logitech would be none too happy to have seen that link I saw!
I'm wondering if product suppliers to review sites should now worry about whether the site uses this marvellously accurate advertising?
The text "G5's" further down the page linked to an ad for "Ping" brand golf balls.
Hope this still says the same thing as when I last looked. Just refreshed a few times and it's been linking to several different sites, haven't seen that one again.
Anyway, hope you enjoy it, and I'm glad your own site doesn't use text link adverts.
Dan (another bloody one)
Answer:
There've already been various legal
skirmishes about people buying, for
instance, Google AdWords that match their competitors' products.
And then there's the plain wide word matching that gives rise to, for instance, the Google ads on the Periodic Table Table site that I link to all the time, which've been a bunch of rubbish about a panacea called "Monatomic Gold" for some time now. Apparently people have been crapping on about that for some years now, and of course selling related products, without ever being in any danger of lapsing into comprehensibility.
Speak of the devil
I realise you are not responsible for the adverts that appear on your site, but you have mentioned at least once removing 'unsuitable ads'. If so, you may want to remove the one I've just seen on your front page for the Life Technology Tesla Purple Energy Shield
Not that I have anything against purple energy in particular. I'm sure it's just as good as any other colour.
Neal
Answer:
Heh. I've now blocked any ads featuring the domain belonging to m'verygoodfriends
at Life Technology. It's a wack-a-mole situation, of course; I can add a bunch of Sites I Hate to Google's exclude
list in advance, but I don't know every domain belonging to some whackjob who might buy an Adword that matches
some of my content.
I hope you realise how big a sacrifice I'm making here, though. Can you imagine how many of my readers would have clicked frantically on that ad, hoping to score themselves an Energy Shield before the dealers ran out of stock?
Actually, of course, some people actually do click ads that contradict what a site is saying, and not always because they agree with the advertiser. If you're reading a page about how reprehensible anti-vaccination activists are, and find an ad-link at the bottom that says FREEMASONS USE VACCINES TO NEUTER CHRISTIAN KIDS, you might feel a strange urge to click it. Not only to revel in the craziness, but also to transfer some money from the crazies to the owner of the page on which the ad appeared.
Now here it is, your moment of Zen
You'll love this.
Len
Answer:
And if you hang it from your rear view mirror, it stops speed guns from working on you!
(Either that, or makes your speed seem much higher. I'm not sure which.)
