Just to state where I'm coming from - I've got a keen interest in renewable energy and do believe in global warming.
Here's my take on some of the subjects mentioned in this thread:
Wind power
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Home generation doesn't work well unless you live in a windy area and can afford a large turbine. Large DIY windturbines are the best bet if you have the time and skills, these ones can pay for themselves very quickly. 1kw DIY turbines built from scrap materials are quite common.
When you try to generate your own energy it makes you realise just how much we use.
Wind up torches
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Very much a gimmick and I would agree that a standard torch with rechargable batteries is a much better bet in terms of being 'green' and function i.e. none of this feeble 3 led rubbish.
Electric cars
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Better than ICEs in every respect except one - energy storage/batteries. Electric cars can/are faster, smoother, more efficient, quiter than ICE. The problem is storing the energy, this is where ICE wins.
Solar PV panels
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Low maintance easy energy - the problem is the initial cost of the panels and setup needed to store the energy. Once these can be produced very cheaply (e.g. printed onto plastic) then it will really take off.
Petrol prices still have some way to go before we start to see electric cars become commonplace. Personally, I love the idea of having an electric car and generating my own fuel/energy for it - but the reality is that its never going to be easy.
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here's a good account of someone making their own 2kw turbine. Motoring link - they used parts from a 1995 BMW.
www.itsnoteasybeinggreen.org/forum/viewtopic.php?t...6
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Wind up torches Very much a gimmick
I would have agreed until recently, but I got given a 3 LED wind up torch by my Mum. Contrary to my expectations, it's very good indeed. 30 seconds winding gives a very good, bright, even beam that lasts for 15 mins +, and it's now a permanent fixture in my glovebox. Not as bright as my Petzl SLED headtorch, but very handy.
No idea if it's greener, probably not with the capacitors that are presumably in there, but it's very nice to have a torch that will def work. I can have a look at the brand if anyone is interested?
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I agree Gorden, I too already have a wind up torch. Very useful, in particular that its sure to work.
I wanted something else though that would provide brighter and longer duration light if we had another all night power cut at home next winter. Both have their place, I`m sure.
I think the real breakthrough is LED`s though..
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I agree Gorden I too already have a wind up torch. Very useful in particular that its sure to work.
I'm not so sure about the reliability of these torches. I think most of them have rechargable batteries inside, which of course have a limited lifespan.
I think the real breakthrough is LED`s though..
Cant argue with that!
I'll admit that I actually have two wind up torches - I bought them out of curiosity and for the gimick factor. One has 3 LEDs (trigger operated) and the other has 5 LEDs (handle operated). From the specs the handle operated one can generate about 4w.
I've not had them for very long so hard to comment of the performance long term. So far I find that even the 5 LED larger torch is not as bright as a normal torch (not that the LEDs are at fault - just needs a few more of them).
At some point I'll probably dismantle them to take a peek inside, in fact that's one of the reasons I bought them....
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The thing to remember about wind generators is they dont actually power anything themselves they basically top up a power storage unit as and when needed its the same with solar panels, so when reading the capabillities of a wind turbine its telling you how much it will put back into the system over a set period not what it can power.
As for power you really need to concentrate on the actual gear ratio of the generator a bad gear ratio in the turbine will give you nothing despite the pretty windmill spinning it heart out all day whereas a good balanced system will give you a better output.
Its a common misconception that solar panels and wind turbines will only power things if the weather permits but that not trueits the PSU connected to the panel/turbine that really does all the powering (when you consider that the nearest thing to renewable energy most people have ever seen close up is a solar powered calculator its easy to understand where the confusion arises, personally it took an open university engineering course to show me where my own thinking was totally wrong).
As for wind up torches i love them, i have one here on my desk as i have coin meters for my gas and electric and you can bet if i forget to feed them they will always run out at night, plunging my into complete darkness, i used a conventional torch to start with but having left it turned on after the lights came back on and then finding it flat when going to use again i switched to a windy
Edited by welshlad on 23/06/2008 at 17:15
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Actually the future may hold imaginative possibilities for things like community service as a sentence for minor crimes. People could be sentenced to so many hours on a bicycle-frame generator rigged up in series with a lot of others to run someone's Mig welder or electric cutter.
Perhaps the job of slave-driver could also be revived, someone walking up and down with a whip or taser or the threat to start playing doleful modern bubblegum rock and roll very loudly for hours and hours if they don't pedal harder.
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My thoughts on wind power is to do away with storage and dump the energy into heating hot water or space heating. These are two of the large energy consumers in the home and the variations in output is not a problem if used as supplemental heating.
Large battery banks and charge controllers add a lot to the overall cost.
Of course this doesn't help with powering a PC or charging your electric car up.
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The future of car propulsion is wood gas. See here: freeweb.deltha.hu/zastava.in.hu/wood-gas.htm
(only joking).
On the TV programme Planet Mechanics, Dick Strawbridge and his mate converted a Hilux to run on wood gas; they built it for a woodland trust charity in London. Unfortunately the system looked like it weighed half a tonne and took up half of the pickups load bed.
They had to keep driving over speed bumps to knock excess ash out of the bottom of the firebox, otherwise it would clog up and the engine would stall.
The Yugo one looks a neater more compact system than the Hilux, but the latter one had to be built in about a week AFAIR..
Edited by Rich 9-3 on 23/06/2008 at 17:35
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"No chance of a `green` pure electric car then, when all of the wind farms combined will not even be able to power the nations electric kettles."
Spain now has 15,500+ MW of wind power installed, and met 32% of electricity requirements a couple of months ago; the target is 20,000MW by 2010. The turbines seem to be getting bigger - they're just commissioning some 2MW turbines near our village, and they are huge.
Couldn't comment on the economics, and always wonder what's powering the a/c units on hot wind-less afternoons, but more than 30,000 jobs have been created by the industry.
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What happens when the next ice age arrives and scrapes all the wind farms off the surface? Surely underground nuclear for then, and sun collecting diamond obelisks on south facing mountainsides to enable lizards to re-morph in the millenniums beyond.
Jack the voice developing Lizard to his mate, in what was the Yorkshire Dales. " Stop scratching your back Lad, your generating too much static electricity"
I always take the longer view, consume and drive now, gas and guzzle, while you still can...
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sq
your mind really is a dark scary place isnt it :-)
Edited by Pugugly on 23/06/2008 at 19:07
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""Spain now has 15,500+ MW of wind power installed, and met 32% of electricity requirements a couple of months ago; the target is 20,000MW by 2010. The turbines seem to be getting bigger - they're just commissioning some 2MW turbines near our village, and they are huge. "
Sorry Colin, I just don't believe that Spain produces 32% of electricity requirements from wind power. Considering that the UK needs 76gigawatts of energy to fulfil requirements 15,500 megawats sounds a small amount. To cover 20% of our requirements (on a windy day) we would require 20,000 wind turbines. Does Spain have that many? You also, of course, need the back-up of "conventional" power stations for when Spain is covered by a nice high pressure system (like in most summers and winters) and the wind ain't blowing. Wind power is a gigantic con - a very large amount of the rises in fuel costs for people is to take account of the massive subsidies to wind farms. The problem is that no matter how many wind farms you have, you still need the conventional power stations for when it's not windy (and our coldest weather always occurs in winter when we have those windless, cold nights associated with high pressure) and the problem with most conventional power stations is that you can't just switch them on and off for when wind ain't providing the power - they take a long time to "warm up") By the way, a "2mw turbine" has about a 25% efficiency - 'cos it ain't always windy enough - so it's really about 0.5mw in terms of what it actually produces (though the subsidy is based on 2mw)
Just off for a quick Google about Spain's energy supplies
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"and met 32% of electricity requirements a couple of months ago" - I didn't say how long for! I'm quoting from this:
en.wikipedia.org/wiki/Wind_power_in_Spain
I travel up and down the A6 and A3 frequently and new wind farms appear each time - also the majority of large loads are pieces of wind turbines.
As noted previously, economics and alternatives are another matter.
P.S. - the village's electricity is provided our own hydro-electric plant - so we're doubly green
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I didn't say how long for! I'm quoting from this:
en.wikipedia.org/wiki/Wind_power_in_Spain
The reference in that article takes you to a dead link. However, her is another which refers to two events a little earlier than the one in the Wiki article.
www.treehugger.com/files/2008/03/spain-wind-power-...p
" .... a week ago, Spain's wind turbines produced 40.8% of total demand, or 9,862 megawatts of power.
There's a catch, though. The previous record was 10,032 megawatts, but that was 28% of total consumption because it happened during a week day and demand was higher. So this new record is a relative record, while the previous one stands as the absolute best in electricity produced. Still, it's impressive and we hope that others will pay attention and realize that it can be done. .. "
PhilW is correct to say that the average load factor of a wind turbine will be in the range 25 to 30% if the turnine is carefully sited within a good windy location.
The links posted by Hamsafar and myself at the top of this thread refer to calculations by Prof. David J.C. MacKay, Department of Physics, University of Cambridge.
His aim was to show what would be needed to eliminate all CO2 emissions. That means energy coming from renewables and nuclear electricity, and cars depending on electricity as their primary source of fuel (eg. battery driven or using hydrogen from electrolysis or whatever). This enables the intermittent nature of wind to be taken account of as the charging of batteries can be used to even out demand.
I think it is worth reading the summary
www.theregister.co.uk/2008/06/20/mackay_on_carbon_.../
or the full paper at
www.withouthotair.com/
Professor MacKay welcomes comments on his draft, including pointing out any errors in his logic.
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Given I was replying to the OP, 9,862MW is a fair few electric kettles
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Given I was replying to the OP 9 862MW is a fair few electric kettles
Accepted, and my links were in support of your original point.
Also, contrary to the perception that wind power is not reliable or secure, statistical studies have shown that at least for the UK the pattern and distribution of wind resource is such that wind helps the Power Industry meet the security of supply critieria for the National Grid.
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