Sorry - I came to this late - I am seriously looking for a device to
install here at home and it seems to me that only 2 makers are in the
running, but I would like to be proved wrong.
Renewable Devices (hooked up with SSE to the tune of £9M) and Windsave
(currently looking to float for £55M).
What sets them apart is the connection directly into the mains so they
export energy when it is not being used internally (no batteries).
Supposedly there is a quicker payback.
All the above auguments about efficiency, turbulence, noise, etc apply.
What makes them less than ideal consumer products is the price. I
calculate that the RD genny comes in at £9,000 installed. OK, grants
& payback may offset that, but that is not an attractive price for
1.5KW.
Similarly, but better positioned, is the Windsave at about £1500 for
1KW.
Come on. Whereas this thread is engineering based, due to the
interests of contributors, and the 'big windfarm debate' across the
country is landscape based, I feel this is a marketing issue. If these
were made in volume the cost should not be more than a dishwasher.
Every house should have one.
If you look at a micro wind generator there is not much that is more
complex than is found in a DVD player or such common appliance.
The argument should be to get these into volume production, get people
installing them and the energy equation will change rapidly.
The complexity for the connection apparatus to the grid system are one
of the killer's price wise. Corners cannot be cut as back feeding
after a system fault, particularly from numerous sources could kill.
Also one thing conveniently overlooked is that the ratings quoted for
wind turbines are *always* without exception hopelessly overstated.
Unless you want to go completely off grid forever and all that entails
then the planning implications of huge (or even less than huge)
amounts of wind generation are immense, the consumer will still need
to stump up the costs for conventional plant lying idle for the day
the wind drops. If wind renewable's expand significantly more than
the current renewable's target and compose a large percentage of that
total (as they currently do) the shit would start hitting the fan as
reality bit.
So no amount of windmill building, even up to and beyond T B Liar's
targets will keep the lights on. Tidal barrages might have some future
but again the environmentalists will moan. The ONLY possible future is
nuclear. It will really upset the environmentalists but unless action
is taken now (a firm decision to press the button for a new generation
of multiple nukes in the next 12-24 months) the lights will go out in
a couple of decades (or less).
1kW peak perhaps. What do you really get?
Small windgens today dont pay back.
There are far more significant issues than that. Anyone who bases their
argument on landscape is really missing it.
Yep, agreed. They would be much cheaper than dishwashers. But there are
a number of issues to overcome.
much simpler, but it has to handle far higher powers.
The energy equation wont change greatly, house mounted mills wont
contribute much percentage wise, but they can contribute some. They can
save householders money if theyre cheaply mass produced, but not today.
The block is the now point, no-one is buying so no-one is funding mass
production. There are also blocks re planning, safety, legalities,
noise, effects on house structures, and power feed issues. Hence no-one
will invest.
Matt wrote:
Maybe someone else with more detailed knowledge can fill in, but is
that not a case of suitable precautions not being in place on the
supply companies side? IOW if mills became common, linesmen would never
assume a circuit to be dead or stay dead, and working practices would
need to change to deal with that. And could. If I've got this one right
- if - its todays practices that are not safely compatible with the
occasional backfeeding mill.
There may also be ways to automatically check for mill problems and
isolate any such sources from the grid when needed for work.
not so sure about that. There is always wind blowing in some places,
not in others. Its true that utilisation is not very good, but there
will be some saving, though not as much as is reflected by nameplate
figures or eevrn average output figs. As gennies go theyre the worst
kind, intermittent and unpreditable individually, but less so in bulk.
I forget the actual figs, but ISTR something like 20% of a nations
electricity could come from windmills, and domestic ones wont produce
that much.
Not really, simply a case of less utilisation. If wind made up too high
a percentage, which IRL will never happen, there would be times at
which some generated energy went unused. But price policies will take
care of that. Domestic windgens arent going to be big on output after
all. Even a biggish 1kW mill will average what, somewhere vaguely ITRO
100w out.
Just one part of the puzzle, it will add some.
I agree we need more nukes, theyre the most environmentally friendly
option, and the one practical option for our ills.
Imho no lights will go out though, prices (and energy saving drives)
will take care of that. Attitudes to energy may change as things get
tighter and prices go up. There are various sources of energy not a
whole lot above todays prices, those will come into play when prices
rise. And most consumption will be much more efficient by then. And
quite simply a lot of todays consumption just isnt needed.
NT
On 17 Nov 2005 18:07:38 -0800, snipped-for-privacy@care2.com wrote:
As a "for instance" the electricity selling price (not the cost of
generation) just dropped straight through the floor around five years
ago. As a result a major power station (7% of the installed UK
capacity) went bankrupt and was repossessed by the bankers,
fortunately they had difficulty offloading it as scrap otherwise we
really could be in the shit. That same power station is now on the
market and in a bidding war attracting offers around GBP2bn. Until
there is a coherent national energy policy and stable market
conditions no investor (other than one who has been siphoning off IMF
funds) will contemplate entering the market.
The Tories started this off in the 80's with the persecution of the
miners at any cost increasing dependence on imported fossil fuels, the
waste of North Sea oil revenues on unemployment benefit was deemed
more acceptable than state funded/assisted construction projects that
would provide real labour opportunities and provide something long
lasting and of value to the nation (like a decent rail system or 4
lane M1 etc) The Tories then carried it on into the 90's with
privatisation of the gas and electricity systems and the phoney sell
off of the nuclear industry. The tosser Tory Clone T B Liar can't even
get his head around the rapidly impending crisis after "eight glorious
years"
You're posing half the story only. Basic capitalist concepts tell us
that if the power station were decommissioned and we reached the point
where supply were insufficient, electricity prices would rise until
investors would return to the market. IRL the moves are slow enough and
preditable enough that a major station being decommissioned then
another getting rebuilt would be pretty unlikely.
NT
On 18 Nov 2005 08:20:45 -0800, snipped-for-privacy@care2.com wrote:
What I am saying is the price swings are so violent that one year the
generation is very profitable, then the market evaporates *completely*
because the market was manipulated by certain parties that have less
than this countries interests at heart. More than one company just
went to the wall (witness British Energy for instance) If scrap
prices had been more favourable, and the banks had made the decision
to go for stripping the site there is no way the "market forces" would
have been able to react in time and build new generation. Witness the
same thing happening in California a few years ago. No investment
signals were flashing because the market didn't signal anything at all
until it was too late. Those who did know what was happening and
predicted it ahead of time were sidelined by know it all financiers.
Some of the "informed" just took the severance money and retired to
the woods up in Oregon and now live a comfortable existence "off
grid". The UK market is identical. All the money, from all the
tinpot dictators/football chairmen in the world doesn't give you the
opportunity to jump the queue at the manufacturers and get what you
want years early.
The centralised intelligent planning that went into the UK electricity
market up until the late 70's disappeared forever to be replaced by
almost total inaction throughout most of the 80's (except Sizewell)
due mainly to government restraint and was replaced by the free
market, sweet bugger all, head in the sand, couldn't give a shit
approach post 1990 with the result that Postman Pat's cat half asleep
has more idea of the UK's future power plant requirements than any
slick suited inbred merchant banker making critical decisions for the
future of the UK ever would.
On Fri, 18 Nov 2005 17:39:02 +0000 someone who may be Matt
The problem with "basic capitalist concepts", as taught in O Grade
economics, is that Adam Smith modelled the market of his time. Small
family-owned companies, operating in a local agricultural market. As
a result of this there were few barriers to changing product,
everyone had much the same market intelligence and the interests of
the owners and managers were the same. Markets are rather more
complicated today, but party politicians appear unable to grasp
this.
Well, there was centralised planning. How intelligent it was is a
matter of debate. Two examples.
Scotland ended up with five large power stations (two nuclear, one
gas/oil, two coal). There are others but these are all relatively
small, apart from the oil fired one that has spent most of its life
mothballed. This was the result of unintelligent planning. As well
as the expense, it means that the system is less robust than it
should be. The exception is the Highlands, which has a large number
of small power stations, remotely/automatically controlled and
remotely supervised.
The generators of the time were obliged to generate electricity as
cheaply as possible, with the result that they built large
centralised coal fired power stations that threw a lot of heat away
without making any use of it. Had they been obliged to do the best
for "UK plc" then they would have built smaller more local power
stations, with the heat used for district heating. We would not now
be facing a gas shortage if many homes had hot water piped in,
instead of burning gas to produce it.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
Agree 100%. The Merchant Wankers who run this country can't see beyond
the next quarter's figures.
A quick Google hasn't given the me an update on the current situation,
but BNFL where looking to sell off their Westinghouse division... the
one company with a modern approved reactor design, for sale to the
highest bidder (probably be Far Eastern) just as the world moves into
the next major phase of Nuclear build. Again the Bankers can see beyond
the fast buck now to a potential bonanza 5-10-20 years down the line.
Or maybe they've got the nod from Teflon Tone that he hasn't got the
balls to order new nuclear.
Maybe a really long, hard winter with rolling blackouts would be the
best hope for this country.
On Thu, 17 Nov 2005 23:36:23 +0000 someone who may be Matt
The report at http://www.eci.ox.ac.uk/renewables/ukwind disagrees
with you.
On the myth of wind power being unavailable for long periods it has
this to say:
"Low wind speed conditions affecting 90% or more of the UK would
occur in around one hour every five years during winter;
The chance of wind turbines shutting down due to high wind speed
conditions is very rare - high winds affecting 40% or more of the UK
would occur in around one hour every 10 years."
On the myth of wild fluctuations in wind output it has this to say:
"The most likely change in power output from a diversified wind
power system from one hour to the next is less than plus or minus
2.5% of the total installed wind power capacity. Larger changes from
one hour to the next do occur - a change in hourly output equal to
around plus or minus 20% of the installed wind power capacity is
likely to happen about once per year."
Note that wind forecasting for the next hour or two is highly
accurate and hydro and gas turbine plants can start within a couple
of minutes. The anti-wind claim that coal fired plant running
constantly in reserve is necessary in case the wind suddenly stops
blowing is a myth.
As Energy Minister Malcolm Wicks is reported as saying:
"The only sensible debate about energy is one based on the facts.
This new research is a nail in the coffin of some of the exaggerated
myths peddled by opponents of wind power."
http://www.bwea.com/media/news/141105.html
As for conventional plant lying idle, unless wind exceeds around 20%
of total generation there is negligible extra plant than there would
be if that 20% was generated by nuclear, coal or whatever.
http://www.sd-commission.org.uk/pages/media/list/wind.html and
navigate down to the "Download our booklet 'Wind Power: Your
Questions Answered', for householders" link then Section 5 of the
booklet.
"Many people wonder what happens when the wind doesn’t blow. The
truth is that the national grid system is already designed to cope
with large fluctuations in supply and demand. It must deal with
rapid surges in demand – such as during the breakfast period or at
the end of a televised football match when millions of kettles are
used at the same time.
"National Grid Company has confirmed that accommodating significant
amounts of wind capacity on the electricity system is unlikely to
pose any major operational challenges. Indeed there’s no technical
limit on the amount of wind that can be absorbed by the system – the
issue is simply one of cost.
"Wind power is becoming easier to predict. As it becomes more
dispersed around the country it is increasingly unlikely that all
the UK’s wind farms will be out of action at the same time. To cover
for any shortfall will require a small increase in the ‘balancing
services’ that are routinely used by the network operator. This, and
issues such as grid reinforcement, will add a small amount to the
cost of electricity, which is explained below.
"How will increased use of wind power affect my electricity bill?
"Let’s assume that by 2020, we have achieved the Government’s goal
of generating 20% of our electricity by renewable means – and this
done solely via wind power. In this case, the extra cost to
consumers of integrating wind power would be about 3.8% of the
current domestic charge – around £13 on the average annual UK bill.
If the environmental benefit of reduced carbon dioxide emissions is
calculated and included, the additional ‘social’ cost of wind power
will be less – possibly zero."
Those who want further information can go to the "Download our full
report 'Wind Power in the UK'" link. Section 3 of the report is the
place that covers this issue.
For some information specifically on microgeneration
http://www.sd-commission.org.uk/news/index.php?page=get_article&article_id=FK7OVZ8-BV9MRDZ-HKMFYS8-5OZZIS2
is a good start.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
Never trust politicians statistics. It doesn't take anywhere near that
extreme of wind conditions to cripple the power output from wind farms.
And stationary highs with very light winds over most of the country (as
at present) are a feature of the UK weather.
Rate of change in output is a red herring. What matters is the amount of
conventional capacity that has to be kept on standby and/or used to
produce the difference between wind farm capacity and actual output.
Has anybody got a figure for the actual average output of the current
wind farms as compared with their theoretical maximum?
On Fri, 18 Nov 2005 10:31:24 GMT someone who may be Roger
I don't.
Are you suggesting that the University of Oxford
Environmental Change Institute are politicians?
In the full SDC report I referred to one will read:
"3.5 Capacity and flexibility of wind power
"The need for reserves
"It is commonly assumed that adding significant wind power capacity
to the electricity system will lead to a large expansion in the need
for balancing services, particularly reserves. This is due to an
implicit assumption that the intermittent output of wind power
results in the need for large amounts of reserves devoted entirely
to providing standby power for wind output – this is often referred
to as ‘backup plant’. Therefore, if the average output of wind plant
is 35% of its rated output (its capacity factor), the remaining 65%
must be provided as reserve, or backup capacity.
"This reasoning is seriously flawed, for three key reasons:
"• No generating plant is 100% reliable. Therefore, reserves are
required to cover for unexpected outages on all plants.
"• The rated capacity of the total installed wind plant is of minor
interest to system operators, who make supply security assessments
based on estimates of overall statistical probabilities for the
complete generating mix. This leads to the concept of ‘capacity
values’, described below.
"• Wind power is often described as ‘intermittent’, which implies a
high level uncertainty as to its actual output, but it can be quite
accurately forecast in the appropriate timeframes for balancing
electricity supply. A more precise term might be ‘variable’,
especially when considering aggregate output, which benefits from
the wide distribution of wind turbines across the country.
"Instead, system operators assign all generating plant a ‘capacity
value’ (often called ‘capacity credit’), which refers to the ability
of that plant to contribute firm capacity to the overall system.
High availability plant such as combined cycle gas turbine (CCGT)
can have a capacity value of up to 90%, meaning 10 GW of gas plant
would be treated as providing the system with 9 GW of firm capacity
– the remaining 1 GW allows for outages, both scheduled and
unscheduled. Existing nuclear plant in the UK has recently shown
lower capacity values of 75%, due to a number of problems at
individual plants.
"No plant has a capacity value of 100%, because there will always be
some statistical probability that it will not be available when
required. When determining reserve requirements, system operators
make an assessment of the needs of the system as a statistical whole
rather than considering the needs of each individual plant. This
leads to a treatment of wind output that is different than if it
were the only generating source available.
"Capacity value of wind
"Due to the variability of wind power, its capacity value is more
limited, as it will not be possible to displace conventional
generation capacity on a ‘megawatt for megawatt’ basis. The capacity
value decreases as more wind is installed on the system; at low
penetrations it has been put at roughly equal to the capacity factor
for wind (30-35%), but at higher penetrations the value decreases.
This is because with low penetrations wind output is hardly noticed
on the system, but when this increases, the variability of wind
becomes more noticeable and its ability to provide firm capacity is
reduced. National Grid Company have stated that 8,000 MW of wind
capacity would displace 3,000 MW of conventional plant, with 25,000
MW displacing the need for 5,000 MW. This means that wind power has
a capacity value of around 35% at penetrations of around 6%,
declining to around 20% at penetrations of 20%. These figures, along
with other corroborating evidence, were accepted by the House of
Lords Science & Technology Select Committee in their 2004 report
into renewable energy.
"It is worth noting that the capacity value of wind is higher in the
winter than in the summer, in line with seasonal changes in the
capacity factor. This means there is a correlation between the
capacity value and times of peak demand.
"Lower capacity values have been reported in other countries. For
example, a recent report by E.on Netz, one of Germany’s network
operators, with 44% of that country’s wind capacity, quotes an
average yearly capacity factor of just over 15%. However the UK’s
greater resource means that capacity factors and the associated
capacity values tend to be higher than most other European countries
and comparisons can therefore be difficult. In addition, the
integrated nature of the GB electricity grid, differing trading
rules (eg. gate closure times), and its wide geographical
distribution, separates it from some of the other problems faced in
Germany."
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
They could be and in any event even scientists are not always as
impartial as circumstances should demand.
snip
It seems to me that this argument is based on the average output. No
wind at all might be almost impossible but what about the presumably
near 50% of the time when the output is below average? Sometimes it will
be well below average.
On Fri, 18 Nov 2005 16:28:02 GMT someone who may be Roger
No, it is based on understanding the performance of wind turbines.
There is quite a lot of experience since Delabole opened in November
1991. http://www.bwea.com/ukwed/operational.asp lists the current
position.
Like any other form of generation wind farms can be treated
statistically, but that is not as crude as simply an average output.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
25000MW is about 5000-10000 large wind turbines.
To displace 5000MW, which is about one large or two medium conventional
(or nuclear) plants.
Go figure.
On Fri, 18 Nov 2005 20:43:06 +0000 someone who may be Steven Briggs
If they were all built tomorrow then the largest turbine rating in
use at the moment is 3MW, as at the recently commissioned Kentish
Flats http://www.kentishflats.co.uk Assuming all were of this size
that would be 8333 turbines, or 277 wind farms of that size.
To get that number into perspective the largest 200 cities, towns
and districts are http://www.citymayors.com/gratis/uk_topcities.html
If all the wind farms were built onshore then each of those cities,
towns and districts would have 1.4 wind farms the size of Kentish
Flats. It is more likely that say half the capacity will be offshore
and half onshore.
That is a rather simplified analysis, but it certainly isn't
"covering the whole of the UK with wind turbines", as some suggest.
5000MW is 20% of electricity generation (from the next sentence
which you snipped). It would be delightful if 20% of electricity was
generated by wind power, but it is not going to happen tomorrow.
There is an aspiration for 20% of electricity by renewable means by
2020, but I doubt if that will all be from wind farms.
http://www.scottishpower.com/pages/aboutus_scottishpowerbusinesses_ukdivision_powergeneration_longannetpowerstation?nav «outus_scottishpowerbusinesses_ukdivision_powergeneration_longannetpowerstation
says that Longannet Power Station is the second largest coal-fired
power station in the UK and one of the largest in Europe. It has an
installed capacity of four, 600 MW units. In other words 5000MW is
about two large conventional plants.
I know that Drax (3960MW) is the largest coal-fired power station in
western Europe.
I couldn't rapidly find the largest gas turbine station, but
couldn't find one above 1500MW.
http://www.british-energy.com/article.php?article# says that
Sizewell B has an output of 1200MW. In other words 5000MW is about
four nuclear plants.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
A 2MW one was erected a week ago at M4 J11 (Reading).
It seems to have caused quite some traffic congestion
due to motorists slowing down to admire it.
Ironically, there's been virtually no wind since it
was finished, and mostly it's been barely managing
1 rev per minute.
As is the new farm out near Friday Bridge in Cambs.
Mind you the turbine at the dogs home in Godmanchester every time I go
past there its turning. Dorset seem to appear on any mill databases but
suppose its privately owned.
Be glad when this bloody fine but cold weather breaks, give me a mild
wind anytime:))...
Arklow, Ireland, is built with GE 3.6MW turbines. Total capacity
25MW with 7 turbines. The largest turbines, in prototype testing at the
moment, are 5MW (REpower Systems AG, prototype operating in Germany).
Many sites may be limited to 2-3-4MW units, hence my estimate of
5000-10000 units for 25000MW. Reasonable?
I was taking the 20% that is the capacity factor of 25000MW of installed
turbines, the figure given by National Grid at 20% market penetration.
This allows for intermittent operation, periods like now, winter
anticyclonic conditions when many sites would not be generating at all.
I was thinking of Drax as the large example.
I stand corrected on the Nuclear front, I looked up Torness (near you),
at 1364MWe, assumed this was per reactor, it is in fact total for both.
So 4 or 5 typical nuclear plants (current plants have a capacity factor
of 75%, new build is expected to be 90%).
So to get to the point I was trying to make, let's take Torness again,
an example close to home for you.
1364MWe at 75% capacity value = 1023MWe of useful capacity.
To replace this with wind at 20% capacity value, thats 5115 MWe of
turbines, or 1023 units of the current biggest (5MWe) turbines in
operation.
So lets stick over 1000 turbines, at 450+ feet high, out in the Firth of
Forth. How does that look? Expensive too,
http://www.tsaugust.org/Wind%20Articles.htm#Nuclear
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