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869 publicly visible posts • joined 11 Jun 2009


Shagbook won't take Facebook thrust lying down


Not in the UK

"Facebook" is an American word - I'd never heard of it before the website - so it could be argued that in the UK the company is hanging on to its coat-tails.

DOH! Housing contractor loses unencrypted stick down the pub


memory stick?

It's fine - if it was a Memory Stick (TM), then no-one would be able to read it anyway...

Samsung Galaxy Tab 10.1


I don't think that's right

I don't think drivers can be used to convert a USB host into a device - the hardware limits it to one or the other. That is, unless you have USB On-The-Go, which the computer you are connecting to is unlikely to have.

Diary of a not-spot: Vulture hack vows, I will never pay BT again!


Overhead supplies

My parents live in a small town in Wiltshire where there is quite a lot of 230/240V three-phase overhead supply, with a phase being picked off for each house. As no earth is supplied, there is an earth rod fed through an RCCB (not an RCD) although this may be quite historic as RCDs (measuring current imbalance between live and neutral rather than current in an earth wire) are a relatively recent phenomenon.



I think you mean one-phase.


What powers the media converters?

...because that will provide a path for the lightning.


£30 BT bill?

It's less than half that, and you can shift it to Primus to save a couple of quid and still be able to use override

On grounding (earthing), my solar PV installer said that on the first installation they ever did, they carefully earthed the mounting bars and brackets and were then told to remove the earthing by the inspectors. And TV aerials aren't earthed either, so what's the problem?

Apple Mac OS X 10.7 Lion Part Two


Thought that was symlinked...

...to /dev/null?


"Apparently, its in case people forget to paste."

Then you don't actually remove the file from the original place until you paste it in the new place, i.e. a "mv" operation. I've just tried that in an Ubuntu file browser as I thought it was so obvious that I must have missed something, and that's exactly what happens.

There must be another reason. Illogicalities like this are usually explained by a desire for style over substance, such as the supposedly uber-ergonomic Mac's refusal to have more than one button on the mouse for so long.

Yahoo! reads! your! emails!


Thank you!

Will try it.


You can't go back!

When I accidentally "upgraded" and tried to go back, I found this, which would make Michael Howard proud:

"Can I switch back to a previous version of Mail?

Last Updated: 21 June 2011

We have removed the "Return to Original Mail" link from the help menu as we're strongly encouraging all users to migrate to the newest version of Yahoo! Mail. We will continue to invest heavily in the latest version of Yahoo! Mail, further improving it and delivering more compelling features to our users.

We know that changing to a new interface can seem daunting, so we’ve done everything possible to make the transition easy. We have created help pages specifically for users who have recently switched to the newest version of Yahoo! Mail, highlighting differences that you may notice: http://help.yahoo.com/l/uk/yahoo/mail/ymail/migrating/.

We hope you’ll give this new version a try. It’s our fastest version of Yahoo! Mail yet, with improved protection against spam and advanced features like in-line photos and videos."

In other words - far fewer words - NO!


Magnificent Moon mountain sunrise caught on camera



My first reaction was why weren't they using a colour camera? But then I realised the moon is very grey. Extremely grey - I opened the image in gimp, whacked up the saturation and it looked just as grey.

Or maybe they weren't using a colour camera?

Solar panel selling scam shown up by sting


@AL: what size installation?

Would be interested to know if you're happy to tell us. Presumably quite big for £15k. How is it performing compared with the estimates? What are of the country are you in?

AJ: you seem to be criticising solar installations on the basis that electricity costs will rise to make the FIT proportionately smaller. But as they rise, the amount you save on your electricity bill will also rise, making the panels more worthwhile, not less. Sorry if I missed your point.


You're right

I am planning to live in my house for the next 10+ years; I'd certainly think twice about installing panels if I weren't.

It is a little depressing that this thread is focussing so much on payback. Of course I want to avoid losing huge amounts, but the prospect of fitting panels to the roof and generating some electricity renewably, even if there could have been better ways of doing it, will give me a great deal of satisfaction. I probably said earlier that if my motivation was merely the amount of money to be made out of it, I would not be bothering. Of course you can laugh all you like at that, but it is no more or less laughable than spending money on any other hobby - even beer.


Sorry for my wording

I do know that you can post anonymously while logged in; I just got the words wrong, sorry, and that explains why it looked odd that I didn't know that!

I didn't know you couldn't post without registering, but the end result is the same to anyone except the anonymous poster, so no, it doesn't make me feel any better that moderatrices know who they are! In fact it's depressing that so many postings are deliberately made anonymous rather than just being the result of someone not bothering to register. And of course it makes it impossible to link postings. Perhaps they should automatically be assigned numbers within a thread? That would make life a lot easier I think.

By the way, I see that the site has moved to post-moderation, at least some of the time - postings appear instantly at all times of the day, even though you are still told they will be checked. And I saw my first "this has been withdrawn by a moderator" recently.


@Apocalypse Later

Two things wrong with that posting:

1) The tax on train fuel is not zero, so by your logic, aviation fuel should be taxed.

2) Aviation is not like trains. If you don't understand why, read my previous postings.


OK, you win your battle of semantics

...I'll drop the term "tax break", not that it matters though, because the point is that it is an anomaly (as I have also called it before - may I use that term instead?), and a major one - the form of transport which guzzles fossil fuels like no other (per passenger mile etc) gives nothing back for that profligate waste. I'm a little surprised that you are focusing so much on this tangential point when there are far more important things to discuss, such as (Richard) my rebuttals to your earlier post.

BTW - according to el Wiki, diesel train fuel is not untaxed: "UK train operators do not receive a general fuel duty rebate, though in 2006 the duty on biofuels was reduced from 53p to 8p to encourage the its introduction for train use."


Zero tax is a tax break to me

Thank you for a sensible post this time, or apologies for confusing you with another AC...

Unfortunately you've still got it wrong though.


The tax on petrol and diesel (and bioethanol and biodiesel) is exactly the same per unit volume (shame it's not the same per unit energy). The tax on LNG etc are about half, which is a tax break to encourage their use, just like there used to be for diesel.

The tax on aviation fuel is ZERO.

So it is patently NOT taxed just like any other fuel, and if that isn't a tax break, then I name you as the chairman of Vodafone and claim my 50p.


Same anonymous?

No, I don't see paying tax as the same as receiving a subsidy. A subsidy is income, and tax is expenditure, or reduced income if you like. They have opposite signs.

Even though you won't log in or register, these comically inept attempts at erecting straw men (or simply the inability to understand written language), not to mention the inability to spell "it's", are certainly forming a pattern, so I assume you are the same person.


Come on now

Your (unqualified) assertion about the increase in efficiency of air travel compared with "anything else" merely means it is slightly less dreadfully wasteful now than it was 15 years ago. And Michael O'Leary's excuse that it is only 2-3% of emissions doesn't wash either, both because of the wasteful way in which it is consumed (air travel is never going to be anything other than very energy intensive) and also because it is growing rapidly due to our growing addiction to unfettered air travel.

You are contradicting yourself by complaining about subsidies on solar power whilst stating that research into aircraft efficiency is entirely paid for by the airlines. Tax breaks on aviation fuel are just as pernicious as subsidies on solar installations. The only difference is that one is money being given out, while the other is less money being taken away. Both apply to the same pot of money. So why are you reserving all your ire for solar subsidies whilst ignoring airline tax breaks entirely?

If the airline "subsidy" were removed it could well have a triple benefit of raising more revenue, curbing the increase in (mostly unnecessary) air travel and stimulating the research into efficiency (subject to fundamental limits) you are so supportive of.

And this brings me on to your either/or stance on solar grants vs solar research. Firstly, how do you know that the FIT money is displacing research grants? And secondly, surely the subsidy is helping to get the market going? I would suggest that Sharp's investment in manufacturing panels in Wrexham, for instance, would attest to that. This in turn will feed into research budgets. Surely this cannot be making the situation worse? Open-ended research grants - hand-outs from the politicians you despise, in other words - do not offer the same incentive to produce real results as ones driven directly by competition.

I am not saying that you will get exactly the same result per unit of investment if you put it into subsidy rather than research directly. But you are trying to paint a black and white picture, and that is unfair.


No, Anonymous

...I am simply illustrating that there are tax anomalies all over the place and that I am no more stealing by installing panels on my roof than is someone taking a flight.

Thank you very much for highlighting the stupidity of JP19's accusation.



One company who supplied an estimate/quote talks about supplying a remote (wireless) monitor. Another is trying to flog one for £400.

One company reckons they can get four panels on one part of my roof. The other company reckons they can get six - of the identical panel...



Thank you for your measured and comprehensive response.

I've heard figures from 6% to 10% drop-off if you don't clean them.

Sharp panels, the type that seem to be flavour of the month, are made in Wales. I agree that they could be assembled in Wales from bits made in China. I'm sure most of the inverter comes from the far east too.

It would require legislation to cancel the FIT. I feel it unlikely that this will happen, although I am not naive enough to believe that it is guaranteed. And it won't stop my panels working if it is.



Yes, they may be in Australia, but usually Australians realise there is more than one type of dollar and mention it. Poster said nothing about subsidies either, talking about the full costs of installation. One of my quotes also mentions Sunny Boy inverters, if that's of interest. German company.

One quote I have is for a 1.15kWp system for just over £6k, which estimates income/savings of about £440 a year (~7%) . There are an awful lot of variables though, such as:

- interest rates on the money, if invested instead

- depreciation on the money due to inflation, if invested instead (the generation tariff is index-linked so does not suffer from this)

- rises in the cost of grid electricity, making the savings larger

- drop-off in efficiency over time, equipment failure, etc, making the savings smaller

Savings are of course based on the Standard Assessment Procedure, which Which? apparently doesn't like.

I am convinced that it will be environmentally worthwhile. The efficiency of the installation is not important so long as you get more out of it than the embodied energy. (Sharp panels are indeed about 14% although you can get different technologies that are 19%, both minus inverter losses of about 10% of course, but then you can offset that against losses in transmission which are virtually nil.) Apparently you get something like a 10:1 advantage, though I don't know who told me that figure.

If I were doing it just for the money, I probably wouldn't bother, which may please those who think they are victims of an extortion racket.


Touchy, aren't we?

Sigh. To pick but one example: do you ever fly on holiday? In that case may I have the honour of bestowing on you too your splendid title of "jerk" for taking advantage of the the ridiculous tax dodge that allows you to use huge amounts of non-renewable energy whilst only reimbursing the exchequer (who can then spend it on the poor) with a fraction of the amount that you would have paid if you had used that precious resource in other, far more necessary, ways?

The same way that stealing items from a shop would make you a jerk.

In other words, the same as your analogy of finding a wallet, except that instead of you *acquiring* money you *shouldn't* have, you are *not paying* money that you *should be*. Pretty stupid analogy though it is, as you generally don't have to invest large amounts of money to find a wallet.

Actually, may I use "knee-jerk" instead? It is far more appropriate.

Seems to be a pretty clear case of "he who is without sin..." I'm sorry, but life's not nearly as black and white as you like to think it is.


A challenge

Some lovely rhetoric there, and you make a lot of good points, but you really do exaggerate for effect, and I don't think that helps your case at all.

The likelyhood of builders dropping bricks on my panels is probably about the same per unit energy produced as a tsunami hitting a nuclear power plant :-). Energy consumption is not inversely proportional to light level (Economy 7, anyone?). One failed cell writing off a panel sounds nice and scary but is irrelevant if the chances of that cell failing are sufficiently small. And the cells have bypass diodes, so while a faulty one might be a resistor, it takes far from the full current of the array, so presumably having less "radical" an effect than you say (but then "radical" is not a quantitative term).

I'm with you all the way on reducing consumption. I could talk about the ways I have done this without using one penny of government subsidy, but the sad thing is, it would merely get me dismissed as a "tree hugger", so I won't.

Here's my challenge: convince me that putting solar PV on my house will not generate something of the order of ten times the amount used in manufacture and installation, and I won't bother. I am doing this because I am a "tree-hugger" after all - whoops!



No, the amount exported into the grid is NOT metered (at least for domestic installations), even though you do, as you say, get paid 3p a unit. The installation only provides one extra meter. It is simply assumed that you will use 50% of what you generate, and export the other 50%, so as well as the 43.3p/unit Generation Tariff so you get paid effectively 1.5p/unit Export Tariff.

This might sound odd, but considering that the Generation Tariff is 15 times the Export Tariff, you can see why the initial and ongoing cost of an extra meter to measure how much is exported might not be justifiable.

If you tailor your electricity consumption to use as much as possible of you own generated electricity, you will reduce your electricity bills without making any difference to the amount you are paid for generation and export.


Nope, guess again

I am simply a householder keen to reduce my carbon footprint and getting quotes for installation of PV on my roof, using my own money to pay for it, rather than renting my roof out for someone else to get the generation tariff. But thanks for the compliment - obviously I am making a good case for solar power or I wouldn't be being accused of astro-turfing. :-)

I guess that makes me middle-class and thus evil.

El Reg - your hacks' pathetic attempts to stir up tribal hatred are quite depressing. Why don't you leave it to professionals like the Daily Mail, eh?


Yes You Can...

...feed electricity both ways through a transformer. It will happily send energy in either direction. But the supply authority does need to be informed about your installation to avoid the grid becoming "unbalanced". This may be to do with phases, it may be for overall planning of supply, it may be to ensure that the generation capacity is always less than the base load (meaning that what you export is always consumed locally), or it may be something else - I'm guessing.

Whatever happens, it won't "heat up the pavement" - trying to do that would cause far more serious problems as well as being a waste of energy. What you export really does help to reduce the total amount needing to be generated by other means.


So what do you propose instead?

Burying your head in the sand is the expected answer, but it would be good to hear something more useful.


Not applicable for a UK article

We are talking about the situation in the UK (and similar in other European countries), with government subsidies. This makes it financially as well as environmentally worthwhile. Learn about it here: https://www.government-grants.co.uk/feed-in-tariff.shtml#feedintariffs


Better to have solar power...

...than not. Consider the long-term environmental (and hence financial) costs of burning fossil fuels and a bit of a subsidy on solar power (which will, with luck, help to reduce its price by encouraging research and mass-production) may well be a small price to pay. This subsidy for new installations, by the way, will reduce by 8% per year from next April, if that makes you feel better, and of course the price of conventional generation is forecast to rise steeply, meaning that the proportion of your electricity produced by these means will rise in cost accordingly. If that proportion is reduced due to solar power being fed into the grid, the rise will be smaller.

So, as usual, there's a lot more to it than a headline whinge about "tax".

PS the article is wrong - it's not the 'surplus' electricity that's subsidised, it's all the electricity. The amount generated is metered; the amount fed into the grid is not.


Solar facts

As far as I understand it... east-facing roofs will produce between 10-15% less electricity than south-facing roofs. The difference is not enormous because of the sinusoidal drop-off and because sunlight, when averaged, does not come from a point source - it moves around. Certainly comparing two estimates I have for different parts of my roof, there is an 11% pro-rata drop-off for the east-facing one (although it is incorrectly described as west-facing which may or may not be in the calculation).

Vertical surfaces produce about 30% less electricity - at least south-facing ones, compared with ideally-sloping (20-40 degrees) south-facing roofs.

Shading, even a small amount, is Very Bad, because it can affect many more cells than the ones shaded, due to the way they are wired up. I would think that any panels installed in any area where there is shade would have been put in by cowboys.


On snide "middle class" remarks

Companies are offering to rent your roof from you, paying you the feed-in tariff while they pocket the generous generation tariff. Yes, you still have to be a freeholder, and the overall payback is less, but it won't cost you £6 to £12k+ either.

There are all sorts of tax anomalies about. Consider how disproportionately small is the tax on aviation fuel, for instance.

Peugeot iOn e-car


You've been duped

"On a 15-mile local run, I left with the range indicator at 84 miles and got back with it reading 80, which goes to show how effective regenerative braking can be at extending range if you resist the temptation to accelerate hard."

No it doesn't. It goes to show that you can't believe a range indicator that says you have only used four miles'-worth of energy when you have driven 15 miles (which is not surprising as it's notoriously difficult to work out how much remaining capacity there is in a battery). The only other explanation is that using the braking system recovers more energy than was used to get the car going! This of course is impossible unless you had a following gale-force wind or the journey was downhill most of the way.

Regenerative braking recovers only a small amount of energy. Most of the energy used is lost in friction (air and rolling resistance) and inefficiencies in the motor/drive train/control circuitry. You are placing far too much faith in it.

British Library hands 200 years of history to Google


Shame on the British Library

They were hijacked by Microsoft to act as an ad for Vista - at one point their website was trumpeting material that could only be viewed with that OS. I complained to no avail - obviously they were in Microsoft's pockets. Now it seems that has gone the way of Vista and now I expect they are in Google's pockets, but you're right - at least more people will be able to access the stuff. I'm not surprised to hear about their newspaper deal - they are either corrupt or very stupid.

Toshiba reveals iPad 2 rival


And as the other old saying goes...

There's one born every minute.



NOT everybody wants an iPad 2.

Microsoft eyes Ubuntu and Debian love on Hyper-V


Chairs will fly

"One request that has come to us time and again is Ubuntu and Debian"

...but he had to add, hastily:

"[er,] We haven't seen a lot of requests"


Building your house on quagmire

As I was reading the article I thought how scary it must be to be trying to build Linux on foundations laid by the enemy. You can imagine how they could fine-tune the flakiness just enough to persuade Linux users to dump Linux without dumping Windows. Maybe since Microsoft has been caught employing such fraudulent tactics so many times, the company wouldn't dare do this any more - let's hope so.

Pint-sized 3D printer produced

Dead Vulture

Significant figures

"€1200 (£1056)"

I thought not understanding significant figures was the BBC's job.

Samsung Galaxy S II dual core Android smartphone


NO DVB-T because no aerial

You wouldn't get any signal without a relatively large external, preferably directional, aerial.

Renault readies sub-£7000 e-car for Blighty



kWh - kilowatt-hours - not "KW" by which you mean kW which is a measure of power, not energy.

I'm sure they could find a reasonably secure way of telling you how much energy is available from the battery (a display on it, for instance) and charge you accordingly. But it would still be a lottery as to how much juice the thing contains and therefore how far you'd get with it.

Australia cuts solar subsidies, and not before time



As you say, you need a tank to run the system 24/7. Just how big is this tank? Rather more huge than your average hot water cylinder I would think. And as I also said, you need very good insulation because you are losing heat 24/7 which you aren't with a conventional system which only heats when you need it to.

So, solar thermal heating for new builds certainly; for most existing properties there are large, expensive problems to be overcome.



You use a mixture of glycol and water the same as in a car radiator, but that does not mean it is maintenance-free, which is why I said it needs maintaining. It looks as though freezing isn't the only problem you can get if you don't maintain the system:



Solar panel positioning is not that critical

It's a sinusoidal drop-off from the ideal position - the gradient is shallow either side, so exact positioning is far from critical. They say "south east to south west" is fine, as well as a surprisingly large range of pitch.

If you have a flat roof, the panels will be mounted on a frame which will automatically have an ideal pitch and orientation, so while there is the cost of the frame/fixings and possible wind loading and planning implications, flat roofs can be good sites.

Even if you mount the panels vertically, on a south-facing wall you only lose 30% of output from ideal, and large-scale wall installations are considered viable.

There is one fly in the ointment with PV panels though: shading. A small amount of shade has a disproportionate effect because the cells interact. So while general roof muck on your panels will only reduce the output by 6%, clean off those bird droppings.



Is that a rhetorical question? Assuming it's not, electricity is very expensive and inefficient to store in large amounts, either in batteries or by pumped water storage, and it looks like that's not going to change soon. Instead there are a lot ways of coping with the situation. Off the top of my head:

- If the electricity is generated thermally from solar concentrators rather than PV cells, store the heat overnight, apparently in tanks of salt

- Regulate the charging of electric car batteries; you could imagine imposing a lower tariff on people who don't need their vehicles to be guaranteed to be charged to 100% as quickly as possible

- Regulate loads such as freezers, where they can survive for a long time without their motors running. This can be done simply by signalling the grid's condition by varying its frequency slightly

We've had Economy 7 in the UK for decades, to cope with the diurnal load variation.

Note that there is a smoothing effect from the average of lots of installations - the sun isn't going to come out and go in at the same time for every solar panel.


Solar thermal not that brilliant

The trouble is, a large installation provides loads of hot water in the summer when you don't need it unless you have a swimming pool, and a small installation gives you hardly anything in the winter - it doesn't really help much with heating. Yes, it's more effective in underfloor systems but those are so slow to act that there is a big efficiency penalty if your house isn't super-insulated or constantly occupied. Unlike electricity, you can't export the excess, and it's harder to change your consumption patterns to take advantage of it. Yes, you can store it more practically than electricity, but even that requires huge heavy tanks which aren't often practical in existing buildings. In theory you can harvest energy from sunlight much more efficiently than with PV panels, but in practice there are lots of negatives. It's also heavier and harder to install than PV and vulnerable to freezing if not maintained properly. That's why I haven't installed a system.


Not really

Just because PV cells are semiconductors doesn't mean that making better PV cells is the same as squeezing more transistors into a unit area and using them more intelligently, which is what is increasing the price/performance of integrated circuits. There is a hard limit of the intensity of sunlight so once you get towards 100% efficiency - not even an order of magnitude better than current cells - the performance can't get any better so you are limited to trying to get the price down. And while that will undoubtedly happen, do bear in mind that the cells are a relatively small proportion of the cost of the entire installation: a computer doesn't have to be made to survive outdoors on a roof for decades, nor does it have to be fixed up there.

I take your point - things will improve, but not in a Moore's Law kind of way.

The subsidies are being wound back in the UK from next April on - see my other posting.

Thumb Up

About to take the PV plunge

I have just had an estimate for installation of a 1.38kWp PV system (6x230W panels; 11 sq. m) on a due-south facing roof for £8700. This is a lot of money. However, for every unit I generate I get paid 43.3p feed-in tariff (FiT) which is supposedly inflation adjusted and protected for 25 years. Also, it is assumed that I will export half of this to the grid (this part isn't metered), so I will get paid a small amount more. Also, what I generate is free for me to use, so that will reduce my electricity bills when the panels are generating, and this can only increase over time. (I am thinking of trying to cook up an intelligent immersion heater controller which only sucks as much power as the panels are giving that is not already being used. Might be quite a challenge!)

The estimate states a predicted income from the FiT of £16k (using independent approved methodology) or a total saving of £21k over 25 years. I am reasonably confident that the panels will last that long - this is a well-proven technology.

I am also in a solar club which will give me a retrospective discount of up to 12% on the cost depending on how many others take the plunge. Not expecting more than 5% discount really.

The FiT is set at the time of commissioning and goes down each year. This can be thought of as a disincentive to wait until the panels/inverters get cheaper/more efficient. I was told (I am just reporting this...) that developments in panels are heading more in the direction of lower production costs rather than efficiency improvements, so will most benefit those with area to spare for panels, which I don't have.

Nobody can predict energy prices, interest rates and inflation, so it's impossible to know exactly how this will compare to investing the money instead. However, these panels definitely reduce greenhouse gas emissions and fossil fuel consumption (they produce far more energy then is embodied in the installation) and for me, importantly, there is more to it than how much money I get out of it compared with how much I put in - there is the element of satisfaction which makes it more valuable than a simple financial calculation.