Wednesday, January 26, 2011

Combined heat and power - the way forward?

Here's a demonstration of a domestic fuel cell, from Ceres. These systems behave like gas boilers from the point of view of generating hot water and heating, but have the added benefit of using the wasted energy to generate electricity, at a level of up to a kilowatt or so. This has the effect of reducing carbon emissions and also reducing the consumer's electricity bill.

Ceres are in the process of getting their micro Combined Heat and Power boiler to the market place. Based on a quick trawl across the internet, there are a couple of boilers already on or close to the market which do this - the Baxi Ecogen, which is expensive (the boiler itself seems to cost around the £6000 mark) and relatively powerful (it is capable of providing 24 kW of heating for water), and the e-on Whispergen, which seems to be less expensive but also less powerful (around 12 kW of heating). I just checked our boiler - which is a combi boiler, so has to produce hot water on demand - but it's capable of an output of 30 kW. All the mCHP systems I've seen seem to work on the basis of using a hot water tank. Maybe the next boiler we get is going to require us going back in the direction of having a tank....

Solar PV - the difference a month makes

It's not that loads has changed - the days since we had the solar panels installed have been predominantly grey - well, this is an English winter, after all. However, the system is responding differently already. Even on the greyest day, the panels seem to be generating power from around 9.30 to around 3.30, and we rarely seem to have the "zero output" days that we had for the first few weeks.

There hasn't been a huge change in the sun. In the first month after the winter solstice, the noon position of the sun only gets three degrees higher in the sky, and the day gets less than an hour longer. However, it is evidently enough to take it closer to the light threshold at which the panels start to generate.

We have discovered that the panels weren't optimally connected to the inverter (the south and the west facing panels should have been connected as separate "strings" into the inverter, and they were in fact all linked in series), so Rayotec are coming back to rewire a section of the system. I'm hoping that they are going to find out how much it would cost to install the PC interface module at the same time. I don't know whether this will have a noticeable effect on the performance of the system. In theory, the output of the two different sections of panels can be optimised separately by the inverter: I don't know whether this is likely to give a 1% or a 10% improvement.

The peak output of the system so far has been just over 1000 W - it has reached that on four days, the first after the solstice being 9th January - and the highest total output we've seen has been about 2 KWh. The total output of the system since installation is a mere 13 units, though we lost a couple of days which ought to have been good as a result of our messing around with the system.

Monday, January 24, 2011

Religious freedom not dead yet ...

... at least in the US.

Martin Gaskell was the front-runner for the post of director of University of Kentucky's (UK, confusingly ...) MacAdam Student University, but as news of his religious commitments spread, it seems that opposition to his appointment did too.

UK has paid Gaskell $125,000 out of court in return for dropping a federal religious discrimination suit.

H/T Telic Thoughts

Saturday, January 22, 2011

I think I disagree with my lecturers ...

... and the course hasn't even started yet!

The course is U211, Exploring the English Language, which is not technically due to start for another week or so. However, in a bid to get ahead, since I really don't think I'm going to have the 15-16 hours a week (!) that it claims I need, I've reached the section on accents, chapter 5 of the first book.

The focus in the course has been that no one variety of English should be privileged. That's the sense of the background reading - Crystal's "The Stories of English" emphasises the fact that the conventional narrative of the rise and rise of English disregards the fact that "standard English" is only one facet of the English language. Graddol's "English Next?" explores the issue that English is, in world terms, dominated by non-native speakers. And the opening chapters of the first book have been keen to emphasise that the prescriptive approach adopted to the language in spelling, grammar and pronunciation has only led to one of the expressions of English that we see today.

In discussing accents, however, I think the course goes too far. I am quite happy that in general, accents don't in themselves say anything about the intelligence of the speaker - I've known too many English speakers from all over the place to think otherwise. I'm also quite happy that RP is not a "non-accent".

However, in discussing accents, the focus has tended to be on aspects of pronunciation that are "neutral" - for example, glottal stops or dropping aitches ("ge' inside the 'ouse!"). There has been no discussion so far on the fact that a few aspects of accents quite often betray a level of ignorance of English, or illiteracy - for example, one feature that arises often is the use of "of" where "have" is correct in English (as in "I couldn't of"). The sense I get from the course is that it seeks, in quite a postmodern/pluralist way, to affirm all users of English, regardless of how the language is spoken. (In true postmodern fashion, of course, the language adopted for the course is itself standard English, and I strongly suspect that a response to the course that was not would be likely to raise eyebrows).

I'm trying to imagine how the writers of the course would respond to this issue. They might suggest that English is mutating so that "of" instead of "have" in this context will be considered acceptable usage. But if this is to take place, then sections of the rules of English relating to particles and verb tenses have to be basically disregarded, and in the fullness of time, this would be likely to tidily erode the comprehensibility of the language. They might suggest that there is a difference between an accent and an incorrect usage - but the emphasis hitherto has been that there is no "incorrect usage" - just different, and people need to swim with the tide in this regard. I'd be interested in hearing their thoughts on this.

Personally, for what it's worth, I think that whilst the prescriptive approach is wrong, and fails to take into account many valid expressions of English, the people who write the course are also wrong if they are saying that all expressions are equally valid. There is some discussion about the tone used for science writing, which has taken shape over the centuries, and the writers accept the requirements of the medium. More generally, whilst RP and Standard English have no right to a privileged position in the canon of English language beyond their usefulness as being most widely acceptable, I don't think that the substitution of varieties of English which undermine its ability to communicate can be regarded as progressive.

Friday, January 21, 2011

Monitoring energy use

We've been using a Current Cost Energy ENVI-CC128for a while now.

Good bits first. It is very easy to fit - the device works (I assume) by electrical induction. The sensor has a clip which fits round one of your mains wires, and then communicates wirelessly with the monitor. It sets itself up automatically, and it is apparently compatible with further units, which can be added and set up with similar ease.

If you are displaying this visibly somewhere, the feedback on power usage will almost certainly result in you increasingly switching off unnecessary lights and appliances. This is how it is likely to pay for itself. We have notices changes in our behaviour, and in the event that you don't know which the expensive lights in your house are, this will remind you.

Now the not-so-good. The sticky pad which is supposed to support the sensor isn't strong (or alternatively, large) enough; our transmitter thingy has ended up falling off where it was stuck. The velcro join is fine; it's the sticky pad that doesn't hold the weight of the transmitter when stuck to a smooth plastic surface. Maybe I needed to press it on harder, but I'm wary of pushing too hard on the side of the consumer unit!

Most of the displayed information is, to be honest, a little over-the-top and limited in value. The bar graphs have no scale, so don't really offer much except a vague comparison. The "cost" indication is all very well - it can be set to what you are paying - but the sort of person who can make sense of the concept of electricity units is likely to also be able to make deductions about cost from those values.

We are generating some of our own electricity (with solar panels). Unfortunately, the means of measuring energy use is indifferent as to whether net current is flowing into or out of the house. During the day, when we aren't using much electricity, and the solar panels are generating, we become a "supplier" to the grid. However, the device assumes that this is power being used, artificially inflating the figures for the day. It's fair to point out that this currently isn't likely to be a widespread issue ....

Finally, there's the issue of software. The data from the device is output through an Ethernet connection - but a weird Ethernet connection, which apparently has to connect to a USB dongle - which means that if you want to use this with a computer, you effectively need to buy another piece of proprietary hardware. Other people have commented on the quality of this - their comments, in my opinion, make me wonder whether simply buying a more computer-friendly monitor might make more sense. Also, too much of the software is only available remotely - your power usage being sent to a server on the internet, rather than being analyzable by you. I don't think this is the best way of doing it, and again, my hunch is that there are other devices that are likely to be more user-friendly.

However, if all you are looking for is a power monitor which will encourage you to switch things off, and show you what is going on electrically in the house, this is an excellent little device.

Friday, January 14, 2011

When to wean babies

Interesting news published today, in the British Medical Journal.

We were slightly surprised when new parents that we knew of said they intended to exclusively breastfeed their children until they were six months old. Evidently, this was because we were out of touch with the current recommendations. In accordance with the prevailing advice when our babies were small, we had started weaning our children at around three to four months. None had seemed any the worse for it, and to be honest, by the time they were that age, they seemed ready to move onto something other than milk.

The report is interesting, as it explains the history of the six month recommendation. Ten years ago, the World Health Organisation advised that children universally be breastfed for six months. Breastfeeding is the best option for small babies, and clearly where access to clean water and safe and affordable alternative food supply is limited, continuing to do this while possible is a good idea.

Initially, Western countries seem to have largely ignored the advice, and it was only in 2003 that a health minister said that the UK would comply.

In actual fact, the case for and against starting weaning before six months is quite balanced, from a scientific point of view. Whilst breastfeeding reduces the risk of infections, there's some evidence of undernutrition in children who are exclusively breastfed to six months in Western countries (the BMJ references studies in the US and Sweden). In any case, a lot of children are weaned early and successfully regardless of the advice - the effect of such guidelines can quite often be to lay a burden of guilt and anxiety (or smug self-righteousness) on particular sections of the population (largely middle-class) when the guidance is simply ignored by the rest.

The Royal College of Paediatrics and Child Health, the Royal College of Midwives and the National Childbirth Trust have lined up in support of current guidance. The comments from the RCM are interesting. Their spokesperson said:
I believe that this ... plays into the hands of the baby-food industry which has failed to support the six-month exclusive breastfeeding policy in the UK.

There is evidence that some babies do die in developed countries from inappropriate young child feeding, such as the introduction of solid foods earlier before their swallowing mechanism is mature enough or they have fully developed the capability to cope with solid foods.
The fact that the baby-food industry stands to gain or lose has little to do with the medical evidence - it's more strongly suggestive of an anti-corporate bias in the commenter. Similarly, the fact that the baby-food industry hasn't supported a policy signifies little, particularly if the alternative, which they were able to make money from, seemed to work just as well. For what it's worth, the total income of the baby-food industry from us before our children were a year old was probably around £10 (with the exception of expenditure on formula milk - but that's another story). And there's always a risk of babies dying as a result of inappropriate young child feeding. There's a risk of babies dying as a result of all sorts of things. It's one of the depressing things about babies being born is that they are often born to people like us who are barely competent to do anything with them, and have to learn quickly on the job, generally under massive sleep deprivation.

However, this report has the effect of drawing attention to the fact that the six months advice was advice given with a world readership in mind, and is more to do with hygiene than scientific evaluation of nutritional requirements - and where it's down to that, the conclusion seems to be that the evidence is neutral. That, of course, should hardly surprise us - the world hadn't fallen apart before the WHO recommendations came along.

Saturday, January 08, 2011

How good are Kindles?

I saw a recommendation of a book by a friend on Facebook, with a link to the Kindle edition. I clicked through to that, and paid for it using one click, confirming that I wanted it sent to my Kindle. I picked up my Kindle and switched it out of "sleep" mode". By the time I'd done that, the book had been downloaded, and I was able to start reading.

The Kindle itself is pretty small and light - with the case we bought separately for it, it's the size of a small paperback. It stores up to 3500 books. In any case, you don't have to keep books on the device. Once they have been bought, they can be re-downloaded to any of your registered Kindle devices - my Android phones also have a Kindle reader on them. There didn't seem to be much point in putting the PC Kindle reader on my computer, but it's an option. We have lots of books in the house, though less than 3500, I think - the thought of being able to extend my library without needing more shelves is wonderful.

Saturday, January 01, 2011

"Holy Child" ...

For years, one of the most common hits on my blog has been from a person or people who have searched for the words of the Dudley-Smith carol, "Holy Child, how still you lie". Several times a week, I think, for years. Here's where it is referenced on my page. Just quickly ... if you are the person (or one of the people) who comes here as a result of such a search ... why?