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Stop the digital deluge

I read Robert Latham's letter regarding analogue and digital broadcasting in the January 2012 issue of E&T with interest. For some time now I have been trying to come to terms with the technical aspects and programme content of British broadcasting.

We have finally been forced into digital TV with its flood of extra channels, most of which are pointless. The technical performance of the system leaves a lot to be desired, with poor programme timekeeping, frequent loss of information, abrupt cutting-off of programmes to adverts and frequent glitches in sound and vision. I have lost count of the number of times I have had to reboot digital receivers of various types for both myself and friends.

Radio frustrates me. I use both analogue and digital receivers at home but the one I use most is analogue FM because it is so easy to use: finding stations on an analogue scale you can see the whole spectrum of stations at a glance and then go straight to the one you require. I find the way power-hungry DAB radios tune most irritating and slow, especially if you need to wait for the text to see what is being broadcast, clicking serially through lots of stations to find the one you require. I also find that DAB stations seem to disappear and new ones appear on a regular basis.

Most local radio stations seem to follow the same format with frequent irritating adverts. Where has middle of the road, easy listening music gone from radio? An example being Radio 2, which I believe was supposed to replace the Light Programme, as the name suggests, broadcasting light entertainment and music. We now do not have a national station that provides this. Quite frankly, I cannot see the difference between Radio 1 and 2, almost all the music on non-classical stations is of the same form – DJs talking rubbish, punctuated by noisy pop music. Where is the pleasant music of previous years introduced by presenters who could speak proper English?

I would like to know how British broadcasting has moved into this mess, especially in music content. Dumbing down? In my opinion, without doubt.

While I am not against progress, the way in which the transition to digital has been handled has been disgraceful. The present broadcasting formats in radio and TV seem to be continuing regardless, and it seems we licence-paying listeners and viewers must just accept that this is, on the whole, what broadcast entertainment now is.

Will broadcasting ever return to some balance and sanity? I miss Edmundo Ross!

David Illingworth MIET

By email

 

Make national roaming mandatory

In his article 'Finding 4G's Grid to Go' (January 2012), Prof William Webb mentions national mobile roaming, an idea I have long considered but never seen mentioned elsewhere.

Having four main mobile networks in this country, each with its own set of masts, is hugely inefficient, especially in low-density areas. My own choice of network is predicated solely on which one gives me a signal in all my most frequently visited places, but even that one has dead spots. Visitors from abroad can roam onto several UK networks, so annoyingly get better coverage than a native.

My solution? Mandate roaming between UK networks. When you roam to the mast of another network, then your home network pays it a termination charge, which it would not be allowed to pass on to you. If all networks have equivalent, though not necessarily overlapping, coverage, most of these back and forth charges cancel out. There are advantages:

Networks putting up new masts in rural areas would be able to recoup their capital cost by levying termination charges. There is an immediate financial incentive to networks to make their coverage better, so overall coverage should improve. Conversely, a network which falls behind in coverage can make a management decision whether it's more profitable to add more masts or pay the charges. Users would experience better coverage, especially in rural areas. The environment would be improved by having fewer total masts with less duplication.

I can't think of a single disadvantage. How about it Ofcom?

David Watson CEng MIET

Reading

 

Solar economics

Clive Reader (Letters, December 2012) should not include the capital cost of a domestic solar installation in calculating return on investment. The facility will remain part of the fabric of the building and thus add to resale value. The lifetime and hence depreciation of PV panels is extremely difficult to predict as there is insufficient experience with this technology and linear depreciation does not work. It is equally difficult to predict the life-expectancy of the inverter, which is under considerable stress when the DC voltage on the panels is high, but five years may not be unreasonable.

A further point is reduced consumption from the grid. To what extent domestic consumers can save on imported electricity is largely a lifestyle issue, but potential savings can be considerable. I am a domestic microgenerator receiving about £0.44 per kWh feed-in tariff. I have had a 2kWp PV installation for one year and have kept a very close eye on it, logging relevant data every day and comparing predicted to actual performance.

Obviously weather plays a crucial role in PV output, so one year's results cannot be claimed to be typical. My installation has produced 1.68MWh in total, averaging 4.6kWh per day over. The average reduction in imported power from the grid is 23 per cent compared with the previous 12 months.

On the above basis, I calculate my return on capital as 7.2 per cent in this first year. Should electricity tariffs rise in coming years, my returns will improve still further. Even at the reduced feed-in tariffs in force since 12 December, I believe financial returns on domestic PV are good compared with cash in the bank or stock market yields. Add to that the undoubted satisfaction of producing totally emission-free power and it's win-win!

Peter Aknai CEng MIET

By email

 

Am I alone in thinking that the government programme to encourage the domestic uptake of PV solar generation has not been thought through properly?

First we have the reduction of the feed-in tariff from 43.3p/kWh to 21p announced at very short notice. This has disrupted the solar power industry and is being challenged in the courts. If it turns out that the 43.3p offer has to be retro extended, then people like me who were offered a £3,000 reduction in installation cost if we slipped our date to post-12 December will feel a bit miffed. One wonders why the government could not have offered a gradual reduction in FIT, related to the increasing number of consumers buying PV systems.

Secondly is the issue of where to make the physical feed-in connection with its associated generation meter. At first sight, the logical place would appear to be on one's supply panel between the 100A incoming fuse and the meter. This would not only allow the meter to be read as easily as one's normal supply meter but, more significantly, would not interfere with the measurement of energy used by the property.

Our PV power is fed in via the MCB panel and our meter goes backwards when the level of solar power generated exceeds the power demand of the house. We are told that, in time, our meter will be replaced by one that does not go backwards. But even when this happens, it will still give an oddly false picture of domestic energy use. So in addition to the 43.3p/unit generated, and the 3p for half the units we generate, we will also get reduced electricity consumption bills – especially in the summer.

Presumably the PV system suppliers are not allowed to tee in upstream of the supply meter because this is meant to be 'secure' against unauthorised connections. But bearing in mind that the PV system has to be installed by an MCS certified supplier, it seems reasonable to believe that such a supplier could also be trusted to provide a tamper-proof connection to the PV inverter output. The current situation will surely present a nightmare when it comes to energy suppliers trying to reconcile domestic energy consumption readings with supply meter readings of central generators.

There is also the disappointment that the inverter will not supply power unless it senses that the mains supply is present. If we have a sustained outage we will not be able to use any of our solar power to drive a fridge or battery charger. Of course there is the potential worry of back-feeding 230V into the local mains supply cables – but surely a mains-sensing, static switch would overcome this problem?

Mike Wooldridge, MIET

Henfield, West Sussex

 

If you study the UK's load demand curve and work out how renewables help to meet this it is obvious that the current range have not displaced a single generator. It is the opposite case as my PV panels use 20W all the time the sun is not pointing at them. Inverters show zero power not the true minus 20W. A large turbine uses 5kW when it is not running to keep it warm or cool.

This country no longer makes aluminium as the electricity costs are too high. My PV panels are made of aluminium and come from another country. The inverter, switches, meter and protection MCBs are all made outside this country using fossil fuels and emitting carbon dioxide outside UK.

So I have spent £4,000 supporting industry abroad. I receive £1,100 per year for my electricity, mainly in the summer, to save '97 per year of electricity out of the local coal-fired powerstation which is paid to me by other electricity consumers for the next 25 years. In the winter, when the demand is greatest, my PV panels consume electricity for 80 per cent of the time. The problem is no-one bothers to work out when the carbon-neutral date would occur for any of the renewables. Some studies say that with backup power for wind turbines using gas turbines, the carbon-neutral date is never reached and all we are doing is using fossil fuel to add an extra layer of electrical power generators.

If we were serious about renewables and not using fossil fuels we would build a tidal barrage with power generation across the Severn and the Tay, where tides are at different times and are fully predictable.

Mike Travers FIET

Saline Fife

 

Real news

In his contribution to 'For & Against' (January 2012), Gareth Mitchell attempts to make the case for the BBC's coverage of science and technology. Yet when the discovery of the Higgs boson was announced on the BBC it took only fourth place behind a number of relatively trivial items of only ephemeral interest.

This was one of the biggest real pieces of news in years, worthy even of an interruption to a running programme. The fact that neither the Beeb, nor anyone else, seemed to think so is a sad reflection on our society and its lack of education.

Quintin Davis

Leatherhead

 

Spidola's remarkable batteries

The Spidola transistor radio, which features at number 7 in Vitali Vitaliev's 'One 2 Ten of Soviet design icons' (January 2012), actually came to Britain via a chain of shops called something like 'Scientific and Technical'.

These mostly sold products of dubious merit, such as Galilean binoculars with high magnification and a field of view of about 1 degree, but the Spidola (I think it cost £9/19/6) worked well. It had a 'turret tuner' (a large rotatable drum carrying the RF selective circuits, with switch contacts to connect to the rest of the circuits) and, of course, germanium transistors. I think it had six wavebands, and the drum also carried the six tuning scales.

Unfortunately, after a few years one of these failed with high leakage current, and to my surprise I could not get any decadent Western transistor to work in its place.

But the most remarkable features were the four D-size cells that came with it. Inside a very utilitarian red cardboard sleeve was a blemish-free mirror-surfaced zinc can. They seemed to have an infinite capacity – I didn't use the radio every day or for long periods, but they were still going after four years.

John Woodgate

Rayleigh, Essex

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