Energy and Oysters
Sizing up the Quest for
Renewable Energy
A
Light-hearted Look at
Heavy-handed Projects
Dave Mitchell
Leaning heavily on:
SUSTAINABLE ENERGY – without the hot air
By David J.C.MacKay
and
paying homage to
The Hitch-hiker’s Guide to the Galaxy
By Douglas Adams
Scarthin Books 2012
Oysters and Energy
Numbers are famously feared to “phase” folk. Even in the
so-called serious press and Radio-4 culture they are used just to impress rather than
to inform. Few journalists and commentators appear to understand let
alone have the ability to employ numbers to inform the public. Among the
innumerate is numbered at least one Chancellor of the Exchequer.
A typical misuse of numbers, from a 2010 issue of the
Independent newspaper’s magazine supplement:
“In 1860, the three oyster companies in Whitstable alone, employing
more than 100 boats and over 500 people, sent 50
million tons of oysters to London.”
Let me illustrate ways I customarily make sense of, and check
the plausibility of numbers. This is a million tons of oysters a week, 125,000
tons a day or 5000 tons an hour – 6 times the rate at which coal is fed up the conveyor into
a typical German 2GW power station, such as Ratcliffe on Soar. Allowing for the
weight of inert shell, maybe the oysters could be burned to produce 8MW of
electricity – about a fifth of our generating capacity (from about a quarter of
our one-time coal-mining production). – Out with wind-turbines, in with Oysters! It’s also
10 tons of Oysters per year per inhabitant of London,
or a trainload from Devon every 5 minutes. I think it is
the tons that crept
or was slipped
in there, 10 oysters a year per Londoner sounds about right.
I’m going to quote lots of figures, and most of them I’ve
subjected to what we might call the Oyster Absurdity Check: looked at in other ways,
do they seem ABOUT RIGHT? The whole talk has been produced without using a
calculator; we’re dealing in round figures and in estimates that should be
right to an error of maybe plus or minus about 20%. So far are we from coming
to terms with the long-term implications of our way of life, that such accuracy
is an adequate guide to figures that are subject to variation or cannot be
precisely known. I’m going to stick to metric units, much easier to manipulate,
besides we do have a feel for a kilogramme (about 2 lbs, 1000 make a tonne) and
for a kilowatt-hour – the famous one-bar electric fire or fan heater.
Human Energy and Power
Running a fit, skinny 65kg body like I used to have up the
Bookshop stairs in 2 seconds, at rather more than 1 metre per second = 700 watts or 0.7 kW, a quick burst of adolescent human power, about the steady output of a horse, 1
horsepower.
Running up a mountain at 1200 meters per hour = 200 watts,
0.2 kW
A fit day-long ascension at 600 metres per hour = 100 watts, )
0.1 kW. Actual useful steady output of a manual labourer, or
a serene old Monroe-bagger, maybe 75 watts on average.
I’ll concur with David MacKay’s (Sustainable Energy – without the hot air) approximation of 1kwH per day per
person as a ballpark figure for adult human output, we can buy that
much electric power for about 10 to 20 pence. So
that’s what we’re worth as manual labourers – hence our replacement by JCB’s. Think of that when virtuously winding up your torch,
radio or watch to save energy. We need to eat the equivalent of several times
this output of course, as us small chemical engines, are, at about 25%,
somewhat less efficient than car engines and coal-fired power stations. A quick
check on the reasonableness of this calculation. At 25%, we need to input about 4kWh of food,
or about 3500 kcalories (often referred to as 3500 Calories with a capital C)
in heat energy units. Yup, that’s about the sort of daily intake we’re supposed
to need if working normally hard.
Historical Energy Use by
not so ancient Brits
Fortunately, we get a bit of help from nature – already
complex mediaeval and renaissance European societies were very energetic,
founding and naming ALL our villages and towns
– Wirksworth, Bonsall, Matlock, Cromford, Snitterton, Tansley - routing nearly all our town-centre and village
roads, establishing esssentially ALL of our
hedges and walls, building ALL our village
churches and ALL our cathedrals, without having heard of as
yet unborn Watt. In the Derbyshire
Peak especially, we are renting
unfurnished a world built by our pre-industrial foreparents. Interestingly,
hardly enyone wants to actually LIVE in the modern world built by machines –
even in Dubai, those who can
live in detached villas.
These foreparents did have some help in boosting their 1 kWh
per day. Taking just Renaissance England England, around 5 million people had
the power of more than a million oxen and horses to draw on, so this added
perhaps as much as 2kWh per day per person to
their power They had 125,000 square kilometres to divide up between no more
than one tenth of today’s population, so they had lots of woodland – maybe
50,000 sq. kilometres, growing wood at the rate of 0.2 Watts per sq metre. Work
it out: 50,000 x 106 x 0.2 = 1010 watts = 10 million Kilowatts,
2 kWh per person, or 48kWh per day per person – maybe they utilised a quarter
of this, say 12
kWh per day per person. No wonder we are so fond of open fires and campfires! Indirectly, the power of the sun turned their wind and waterwheels, perhaps 20, 000 of
them in England, generating 12kW each, or 50W per person for maybe 10
hours a day, a handy 0.5 kWh per person per day. Also courtesy of the sun, they grew food to feed themselves and their
beasts, used for meat and milk and wool as well as for power, maybe producing
another 10
kWh per person per day so you can see that
they had already, by Shakespeare’s time managed to multiply their personal power output by a
factor of 20 or 30 by what we would call
sustainable methods, producing or at least utilising some 25 KwH per person
per day. Nature provided everyone with 24 slaves. This estimate is
supported by similar levels for today’s Algeria,
Egypt, Indonesia
and other “developing” economies.
So - Back to the Land?
Sorry, there’s a catch. Were the
ten times more of us to attempt to go back to Olde Englande’s way of working
and living, that 25kWh per person per day would be reduced to 2.5 kWh per person per
day. That’s what a back to the land, self-sufficiency, backyard-windmill-and-chickens
life would mean. Maybe we should indeed envy France,
which supported a mediaeval population of some 20 millions, a full third of
today’s number, on 4 times England’s
land area.
Back to Today’s Feasting on
Energy
How much power in total do we ACTUALLY use per head per day
in early 21st. Century Europe – well, it’s
hard to be exact, with all the global trade and moving around, but the figure
seems to be about 125 kWh per day. 125 kWh per day!? I’ve seen an estimate as high as
140kWh per day. 5kW roaring away every hour of the day for
every one of us – 12kW per household!!??
Yes, give or take a bit, it is so, and, at 15p per kWh, we
in Europe can (just about) afford it – £19
per day per head, maybe £50 per day per household, 8 hours work at the
minimum wage –
it is already becoming a strain, may we have some working tax-credit
please?
Where does it come from – well, mostly from coal, oil and
gas of course – hence the global warming we’re warned about. And, on that front
let me say that I fear that we ain’t seen nothing yet – you can’t multiply the
concentration of a gas in the atmosphere by 50% without having effects. It’s
lucky for us that the concentration of
carbon-dioxide in the used air in our lungs is already two
orders of magnitude (about a hundred-fold) greater than the ambient levels, or
we would all find ourselves panting continuously even when resting. Fortunately,
our evolving forbears had plenty of time to accustom themselves to ancient
carbon dioxide concentrations which are scientifically controversial but
probably 2-3 times the present level.
An Everyday Tale of
Cromford Folk
How do we manage to use all this energy? I nip into Matlock
to pick up our Clare from the community minibus, six stop-and-start
miles in the van, about a litre of fuel used, 10 kW-hours used at 30%
efficiency, or about 3 x my daily output of power, or, roughly, input
of food! Maybe with the right equipment I could hand-haul the van to and from
Matlock in three days. I could have walked it easily and gently in two hours,
expending 200 watt-hours and Clare 100 watt-hours, needing about a kWh of food
intake, or about a tenth of the energy actually used, but at the cost of (say) £20-worth of my time. The actual money cost,
doubling the fuel cost, was about £2,30 Afterwards, a cup of tea! – boil up a
litre of water through 80 degrees, 80, 000 calories, 80kcals, about 100 watt-hours.
Well, that’s better, I could produce that much in an hour -but how, in practice
– cuddling the kettle would only get the water to about 350C. Later, a bath for Clare
– 70 litres
through 25 degrees, say 1.5kWh, or one and a half times my daily power output,
but costing me only about 25 pence. A week of baths for Clare for less than the price of a pint.
No wonder pubs are struggling – daily baths for all the family for the price of
a round this Friday night.
These apparently trivial examples indicate how without
thinking we use prodigious amounts of energy in our daily lives. Us Mitchells
have had a very long generation time averaging about 35 years for three
generations now, so my Granddad remembered life in the
late 19th.century – he an iron-ore miner, Grandma a milkmaid
in a Cumberland
village. Sounds mediaeval, but it wasn’t. Their society, with its profligate
and inefficient use of coal – 5 tons or more per head per year – got through over
100kWh per head
per day. The blink in time of 250 years since the Industrial
revolution seems like for ever to us, the profligate use of energy goes back
not just to our own upbringing, or to that of our parents, but far beyond the
tales even of our great-grandparents.
Can this go on – of course not! – the reservoirs
of fossil fuels are finite, only, typically about100 years of them are left at
current usage rates. Global warming is just a little sibling of the family problem of use of finite and
irreplaceable fossil fuels to provide energy – we’d better find other sources
damn quick.
Finite Resources Last for
Ever – the Chocolate bar Effect
Actually, this isn’t
quite true. Logically, we CAN make a finite resource last for ever. Consider
this bar of basic best-value chocolate (I recommend repeating this
demonstration). Total
Dave-reserves one bar. Consideration-time’s up! Current comfortable
rate of consumption, half a bar a day. Dave’s reserves will only last
for two bites, two days, then the end of life as I gnaw it. But wait, remedial action,
I’ll reduce my consumption by 50% per day. Next bite is a quarter, next an
eighth, next a sixteenth. It’s the old frog-in-the-well commonplace that I’ll
never quite eat all of that chocolate. Even though there were only two bites of
proven reserves, and half were consumed on the first day, the bar will last for
ever. Coincidentally, we are thought to have used around a half of everything
there is in the way of finite resources in a “day” of about 100 years (200, actually, but
the equivalent of a much shorter period
at late-20th. Century rates), so to make a rough stab, to eke out
what remains for ever we need to use up only half of what remains in the next
hundred or so years.
Generally, the maths is beautifully simple – for 2 years of
natural resources to last forever, we have to halve consumption each year, for
reserves of 50 years to last for ever we have only to reduce consumption by a
fiftieth or 2% per year, for a 100 year reserve to last forever we need to reduce
consumption by a hundredth or 1% a year to make the resource last FOR EVER.
Eventually, of course, our consumption will reach very low levels, and will be
significantly lower after as little as ten or twenty years, but surely such a
rate of retrenchment should be possible.
Not so easy, however. If we continue at present
energy-use levels then even such an apparently small, say 1%, annual reduction
in fossil use implies an enormous rate of increase in the provision of
renewable energy, from a baseline near zero. Fossil fuel use would go down in the
series 100,99,98,97,96,95,
roughly, but renewables must therefore go up in the series 0,1,2,3,4,5. The final 5 in that series is about where we are
at in the UK with regard to electricity generation now, so to achieve just a 1%
further reduction in fossil fuel use, we have to increase pour renewable energy
output from 5% to 6% - a 20% annual increase in capacity; a tall order. You can see why it is that
people quote 10 to 20 years as the minimum period it takes to get from the
pioneering stages to a substantial use of replacement technologies.
Sources of Renewable Energy
How might we replace fossil fuels? By renewable energy we
tend to think of wind, water, tide or sun. However, to quote an article in the
latest Scientific American:
Nathan Lewis of Caltec
says that by the year 2050, civilisation must be able to generate more than 10
trillion watts of clean energy (what he means is 10 terawatts, or 10,000
Gigawatts, which he says is 3 times the average US energy demand of 3.2
Terawatts) (c.f. UK 400GWatts). Damning up every lake, stream and river on
the planet, Lewis notes, would provide only five trillion watts, about half his
target.
We can do that sort of calculation for the UK.
Area of UK is
245,000 square kms, or 245 x 109 sq metres, so if we could generate 2 W per sq metre of our
land area from renewable sources of energy,, we could generate at a
power of 500GW, approximately our current level. But is anything approaching 2
W per sq metre practicable?
Hydro: David MacKay estimates the maximum
theoretical hydro-power in lowland Britain as only 0.02 W per sq metre, (one hundredth of the target) and in Highland Britain
as 0.24 W per sq
metre – average about 0.15 W per sq metre and what
proportion of this could we utilise in practice? – 20%? That gets us down to 0.03 Watts per sq. metre. Really,
the contribution this can make is almost trivial, and just think of the
expense, fun though it might be to mess
about with Archimedean
screws in Cromford Dam.
Wind. Coincidentially (or is it?), the practically
extractable wind energy per sq metre in the UK seems to average about 2 Watts
per square metre ,so we could get to the target by covering the entire country
with wind turbines at the optimum spacing. Actually, probably only about
two-thirds of the country has wind-speeds high enough to justify installing
turbines – but we can probably make up for that by employing off-shore area. If
we wanted only to replace current electrical power generation as end-use then
about an eighth of the country would do. If a quarter of current electricicity generation
is the target,
then about a thirtieth of our land area would suffice. This begins to
sound more feasible, and is indeed about what the UK
is currently aiming for, I think, and not far beyond what has already been
installed in Denmark,
Germany and Spain.
That amounts to an average output of 4 GW, which assuming a 20% load factor requires 20Gw of rated
capacity, only about 10,000
two-megawatt turbines, an investment of only around 20 billion pounds
in today’s money. A wind-turbines-on-all-hills policy seems to be going ahead
in Spain, where
I suspect wild
country is still viewed as wasteland, pending romantic poetical
publications by their equivalents of Wordsworth, Coleridge and Ruskin. More of
Wordsworth’s view of the Lake District later. Averages, however, conceal fluctuations from
zero to more-than-we-need. Wind-generated power needs to be stored for when
required, a knotty problem considered below.
The sun, the sun! Even in this country, it’s often burning down
at the rate of a full kilowatt per square metre – from 10 sq metres, the
footprint area of your house maybe, we can replace a 1 litre of petrol (10Kw) in an hour!
Alas, however, there are clouds, low sun angle and winter - cutting into the
potential is the knife of the long
nights! (not quite original – a rockband got there first). So the average
power available in the UK
is only 100 Watts per square metre. Still, the human body, lazing in the sun all
year would absorb about 2.4kWh per day;
2 kiloCalories if it could ALL be
converted into food. So what about:
Sun via Biofuel? Europe’s best plants in bright sunlight
and warmth can achieve about 2% efficiency in converting our 100 W per
square metre average sunlight into carbohydrate fuel; but the effect of cold
and their tendency to have evolved to switch off in low-light conditions
reduces this in practice to somewhere in
the region 0.2
to 0.5 W per sq metre. What proportion of our agricultural land
could we spare? Well, as much as two thirds of our land area is classified as
“agricultural”, but only about a quarter as “arable”. We still need to eat, and
upland pastures would be very inefficient at producing biofuel, so I think 10%
of our land area is the absolute maximum that could be utilised, so for the
whole country that brings the Watts per metre down to 0.05 to 0.02 watts per metre – like
hydro, symbolic rather than significant.
Was it Fred Hoyle who remarked that the sensitivity of
photosynthesis to different light wavelengths suggested that life had evolved
on a planet with a different solar spectrum to our sun and had arrived here
from space via meteorites. Certainly, if we want to propagate our form of life
in the Universe, something like sending out exploding warheads of poppy-seeds
might well be the best way (but doing the maths is depressing). Plants utilise
the red and blue
ends of the visible spectrum, but with a big hole in the middle –
hence the green
colour of leaves, reflecting or transmitting the unexploited
wavelengths.
Are scientists even now working on genetically modified plants that would
utilise the whole visible spectrum? Their all-sunlight-absorbing leaves would
of course look BLACK. The era of black grass will
then be upon us. Scientists would assure us that they’d built in safeguards
such as susceptibility to a modified Roundup, in case the gene spread – but
black plants being so much quicker-growing, they’d inexorably oust those old
outmoded green species – England’s Black and Pleasant Land would soon be
upon us. A fantasy? “Imagine my surprise” to open an issue of the Scientific American at an article
entitled “Reinventing the Leaf “
“Researchers are devising artificial leaves that could…..convert
sunlight and water into hydrogen fuel, which could be burned to power cars,
create heat or generate electricity, ending dependence on fossil fuels.” These
particular leaves would, however, be entirely artificial and non-propagating.
Phew! The present aim is to get 10% efficiency in convertion of sunlight to
fuel energy.
Sun via photovoltaics Currently, photovoltaics are
very expensive financially and dangerously greedy for rare metals or expensive
silicon products. Nevertheless, they are encouragingly efficient – about 16%
conversion of light energy to electricity is the current standard, 20% the
current commercially available limit, 30% to 40% achievable but so far only in
the lab. So that’s 16 W per sq metre. If we put 20 sq. metres of photovoltaics
on the roofs of 25 million buildings, that is 500 million sq metres, we’d be
covering only a five-hundredth of the UK land area, so our watts per sq metre
on average is down to (surprise, surprise.. about 0.03 W per sq. metre – pretty
trivial once more – and the capital cost of that, even at £100 per square metre
(well below current costs) would be £50 billion.
Sun via Ground or Air-source Heatpumps There is an example in the building where this diatribe was originally presented (the
Derbyshire Eco-centre), a plant said to be able to produce some 20kW of
underfloor heating for an input of about 8 kW – an efficiency of 250% - about 4
x that obtainable from the most efficient gas-burning boiler or from
combined-heat-and-power fossil-fuel generating stations. MacKay estimates an
energy flow into the ground, derived from solar-heating as 3 to 5 W per sq metre, averaged over the
whole day and year, much lower than the
100 watt average flux because of reflection and the low conductivity of soils
and rocks. But at least we do have a figure in the right ball-park again! The
trouble is, our dwellings, offices and factories are packed into rather less
than 10% of our land-area, so the heat energy extractable in or adjacent to
urban areas is going to be only 0.3 to 0.5 W per sq metre averaged over the whole
country. Nevertheless, such a reservoir could supply enough heat for a high
proportion of dwellings. Air-source doesn’t apparently suffer from the limits
of ground-source, but could surely have the effect of significantly cooling the
local air on winter’s days. One might not want to live downwind of a major
conurbation. With airflow halted by evening temperature inversion would the
bowls in which Cromford and Wirksworth lie become intolerably frozen? Would the
cold air of Wirksworth, perfumed by the tobacco of outside-the-pub smokers, pour over the lip
of Cromford Hill, right by the Eco-centre, to immerse the
Cromfordites? I haven’t done the maths on this yet…..
Tide and Wave Power.
The potential around the UK
is considerable,
our islands are breakwaters upon which the Atlantic
presses and around which the tides are divided and accelerated. The energy
extractable turns out, once again, to be in the 2 W per sq metre area – to
match our demand, we have to find ways of harnessing wave and tide over areas
of sea comparable to the area of the UK
– again a daunting task.
We could do some maths for
Wirksworth
25 sq kilometres sounds about right for the area of the
parish, 3 miles by 3. 200 people per sq. km, not far from the English average.
There’s no hydro, wave or tidal power (are there small tides on Carsington Reservoir,
though – a project for Anthony Gell school?). Wind it must be.
25 x 1,000,000 sq metres x 2 Watts per sq. metre – 50,000 kW,
50 megawatts, which amounts to 10kW, or 240kWh per day, for each of the town’s
5000 persons – sounds very useful; just the sort of level we need. – more than
enough on average if a bit short of peak demand. But to generate that, with
turbines that on average deliver no more than about 20% of their rated power,
we would need to install wind turbines rated at 5 times the desired average
power output: 250 Megawatts – 100 very large state-of-the-art 100 metre-tall turbines. 10
x10 at 500 metre intervals. Puts the Carsington or Matlock Moor projects rather
in the wind-shadow. Cost say £250 million or £50, 000 per person, about
£125,000 per household. A lifetime’s mortgage for everyone – that’s the sort of
cost we’re looking at.
Tidal power is predictable, but predictably variable over the year’s lunar cycles.
Solar power is fairly predictable, but VERY variable over the day, Wave and
wind are very unpredictable. We’d need to store lots of energy from the good
times to see us over those windless, and perhaps waveless frosty winter nights
and cold-snap weeks.
Storage by Slartibartfast
You may recall Douglas Adams’ revelation in The Hitch-hiker’s Guide to the Galaxy that
the Norwegian Fjords were designed on the planet Magrathea by planetary-architect Slartibartfast, who won an award for the design. I asked him to
redesign a fjord to store enough energy to keep the UK’s
lights on during a period when the wind doesn’t blow. Let’s assume we’ve
installed enough wind energy to provide in ideal conditions a quarter of our
electricity generation capacity: 10 gigawatts (ten thousand megawatts, ten
million kilowatts) To replace this
during a windless hard-as-iron week in the deep midwinter we need to
store 10 x 24 x 7 gWh– about 2000 gWh = 2 x 109 kWh, which equals 6 x 109
megajoules, 6 x 1015 Joules of energy.
Alas for Slartibartfast
– his greatest work, the celebrated Sognefjord would have to be sacrificed to
progress. The Sognefjord is a deep trough about 100Km long and typically 5 Km
wide. We just need to dam up its mouth and a few side arms at Balestrand,
Hoyanger and Ardal and pump-store energy therein as raised seawater – like the
Dinorwic or Ben Cruachan schemes in the UK
but on a rather larger scale. Dinorwic can store about 1.5 GWh – so we need
about 1300 Dinorwics
(this ties in nicely with MacKay’s estimate of 400 Dinorwics to store two days
wind energy) Slartibartfast pointed out that as the fjord empties back down to
sea level when generating, the dam will need to be twice the average water
height. I won’t bore you further with the details, but, remembering that we
need 1 joule of energy to raise 1 kg through 1 metre, Slartibartfast’s design requires a dam height
of 2000 metres, or about 6500 ft. A less obtrusive policy might have
been to use the wind-generated power to empty out the Fjord to that depth
(refilling it to reclaim the electricity) – but it’s average depth is less than
1000 metres. The high plateau above the Fjord’s mountain walls lies at about
1500 metres above sea-level, so Slartibartfast reports that he can’t meet the
full spec, but can guarantee only about 4 or 5 days emergency supply. We haven’t
put this proposal to the Norwegian Government yet, though there are already
plans to lay a high-tension cable under the North Sea on
the pretext of adding to the flexibility of the European Grid. If the
Norwegians charged a 5p per kWh premium to give the energy back, they’d earn
£75million every time the Fjord was
emptied from 1500 metres. Not to be
sniffed at, it might be a return on the capital cost??
Energy density
Mechanical energy, such as hydro-power is, indeed, a very
volume-consuming way of storing energy. The so-called energy density,( measured
in kWh per cubic metre, say) is very low – imagine trying to run a car on the
energy from a descending pendulum weight.
We could alternatively manage the job of storing the week’s UK
windpower energy using an oil tank of volume 2 x 108 litres, i.e. 2 x 105 cu metres, or 200 metres by 100 metres
by 10 metres tall – about the size of the Argos
distribution centre you pass on the A38 the other side of Burton on Trent. An
oil-tanker-full in fact. Liquified natural gas would do just as well. But has
only about two thirds the energy density of diesel oil. I suspect that some such project may well be
in hand, so the Sognefjord may be safe, at least until the oil and gas run out.
Saving Energy
I know what any Transition Wirksworth, Transition Matlock or
Sustainable Youlgreave persons are going to say. Hold on, we all know that SAVING energy
is a far better and cheaper way to go than trying to generate our present
demand from renewable sources. Indeed the whole message of what I’ve said so
far is to point out the appalling scale of any meaningful renewable energy
project - disruption of great swathes of land and sea, tens of billions of
pounds of investment. Can’t we reduce our demand instead? But
saving energy isn’t easy either.
The RULE OF HALF seems to me to apply almost
universally. We could
all use cars that are twice as efficient (i.e smaller and less overpowered);
we could all insulate
our houses and change to more efficient condensing-boiler or
heat-pump warming – and halve our household energy needs ; we could all
recycle metals, paper, plastics, glass, which reduces the energy needed to make
new finished materials, typically by – guess what – a half. Maybe we could fly half as
often ( I can’t help much here as I don’t fly at all – What never? Well….hardly
ever.). But that only halves our energy consumption – and how are we going
to force people to do that? Only about 10% of us at the outside take any practical
interest in these matters, and most of what we do is talk. Tony Blair for
Instance:“Unless
we act now, not some time distant but now, these consequences, disastrous as
they are, will be irreversible. So there is nothing more serious, more urgent
or more demanding of leadership.” (October
2006).Two months later, responding to the suggestion that he should SHOW
leadership by not flying to Barbados
for holidays: “a
bit impractical actually….”. The Lord of
the Manor declines to halt another Tragedy
of the Commons …. You can interpret “Commons” either way.
Embedded Energy
A big almost logically inevitable problem is that if we
spend less on driving or heating or flying, we’ll have more to spend on something
else, and absolutely everything we eat or buy has oodles of energy embedded (to
use the customary term) in it. In the table below are some examples.
Material
|
Energy cost
(mJ/kg)
|
kWh per kg
|
|
|
227-342
|
100 ( 0.6 kWh per drink
can)
|
|
|
5-9
|
2 - 3
|
|
|
60-125
|
20 - 40
|
|
|
60-120
|
20 – 40 (0.7 kWh per drink
can)
|
|
|
18-35
|
6 - 10
|
|
|
20-25
|
7 - 8
|
|
|
2-5
|
1-2
|
|
Petrol/Diesel
Food
|
20-25
30-35
45 (non vegan)
|
7-8 (6 kWh per kg back by burning)
13
kWh per Kg
15 kWh for average diet
|
I slipped petrol and food into the bottom of that table just
to point out that nearly everything we use is similarly energy intensive- but
of course we don’t burn or throw away the THINGS we use – or do we?? Well, as
I’ve said above, we can recycle materials other than food and fossil fuels, and
that reduces the figures in the above table by a factor of two or three (MUCH
more in the case of Aluminium) – but every time our possessions go through the
recyle cycle, they are still absorbing typically 5 to 10 kWh per kilogramme. A
car, incidentally, even if kept permanently in the garage has an embedded
energy equal to about 100,000 km of driving. The only solution in my opinion
is:
Becoming Poorer
So, how can we reduce our energy consumption down towards a level
that might be sustainable? We have simply to consume less of EVERYTHING;
substitution just won’t do. (Prodnose: what about playing golf instead of
flying?) A free-market economist would jump in here and say – “no need to
worry, the MARKET will take care of all that, as fossil fuels get scarcer and
mining them more expensive, energy prices will rocket and, hey presto, we’ll
all get poorer automatically”. The market, however, has a way of getting
hysterical, of booming and busting, and it only works efficiently if EXTERNAL COSTS are charged to the
producer – which they blatantly are not. Sainsbury’s pay me nothing for the time I waste stuck
at their bloody traffic lights! And, given the contemporary very
long-tailed income distribution, the details of “leaving it to the market”, in
terms of social injustice and conflict, might be very unpleasant.
Prudently Looking Ahead
The Market is not allowed to be very good at sorting out
international problems, either. Unexpected political and military conflicts get
in the way. Our position in the UK
and in Europe generally is one of fragility, our supply routes by air,
sea, rail and pipeline stretch far across the globe. Twice last century,
U-boats came close to winning wars by a successful blockade of Britain.
We only grew our own pit-props AFTER the first war (too late). After
the post-second-war unification of Western Europe the
potential aggressor became the Soviet Union, and -
surprise, surprise! - they built up a very large submarine fleet – over 100
nuclear and many more diesel-powered, based initially on WW2 German designs – I
wonder why? Pit-props should have been
on the pre-first war defence budget and, likewise, the excess cost of generating energy locally, and that means
from renewable and nuclear sources, should be considered as part of today’s defence budget; an alternative to maintaining a “global military reach”. We
can become more secure AND poorer at one stroke. To quote the Economist of September
4-10th. “Renewables in Germany are growing more quickly than in almost any
other EU state…but that is only because consumers pay a large subsidy, some
Euros 10 Billion last year.” Great! They’re making themselves poorer! Such
a better use of high-tech
expenditure than our out-of-date white-elephant Trident
system.
Political Stance
So, can Transition Wirksworth, Matlock, Middleton and Youlgreave
have any significant effect? Directly, the answer is a resounding NO. Indirectly, the result might be to
help educate a public opinion that will make very big central government action possible .
And that’s a remarkable statement, coming from Dave Scarthin, a classic
anti-government, pro-small-business suspected closet Thatcherite.
Oh, and I briefly mentioned the baleful effect of Wordsworth
on our attitude to wilderness, re-branding the useless wastes of the Lake
District as a Shrine to Natural Beauty. A contemporary bard has
taken up arms. Whether he’s for or against the Lakeland Poets and for or
against Wind Turbines is of course a matter of literary interpretation.
Reflections in Windermere by William Wirksworth
I wandered lonely as
a cloud
That floats on high
o’er vales and hills
When all at once I
saw a crowd,
A host, of silver
windermills.
Lake
and trees were hid by sails,
Motionless despite
the gales.
Occasionally one
turned, like star
That shines but
rarely, hid by cloud.
They margined each
high fell and scar;
Round every bay
another crowd.
Ten thousand saw I at
a glance,
Each one in need of
maintenance.
The waves beside them
danced but they
With gearbox jammed
could scarcely turn.
A poet could no more
be gay
At sight of so much
money burned.
I gazed - and gazed –
took one more gander,
How all that cash
could help Ruanda!
For oft when on my
couch I lie,
Nought else to do in
power cuts,
They flash upon the
inward eye
Those warm,
remembered, fossil nuts.
The light’s come on!
– Where’s Dorothee?
Boil the kettle! Cup of Tea!
Dave Mitchell, Scarthin Books.
Written as a talk to “oppose” Evan Rutherford at a Wirksworth Festival Special Café
Philosophique, at Derbyshire Eco-Centre, September 2010; tidied up September 2012
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