Energy policy for the 21st Century.
Total energy usage UK, 2001 about 240 million tonnes of oil equivalent.
density of oil is 42MJ per kilogram, so the energy consumption of
the UK is around 10^13 J/year or 2.79E12 Kwh
This equates to a total average power consumption of 317.35Gw. Or 317351 MW.
This is probably used at an average efficiency of about 50%..heating is
more efficient, car transport less, electricity generation somewhere
between.. so for a wet finger estimate, to replace all fossil fuel by
alternative power distributed by electrical means represents a total
generation capacity of say 160GW.
The national grid has a current capacity of 77GW So it would require
probably a x3 upgrade to cope with using it as the primary energy
distribution network. Not trivial, but not beyond capital
availability...this paper suggests that something in the region of
£2-£10billiion would cover it. FAR less than the cost of a single windfarm.
national grid runs at about 97% efficiency at full load..obviously
somewhat less at reduced power as losses tend to be partly fixed, as
well as load dependent.
a population of about 58 million, in 2001
represents an *average* power requirement (OUTPUT energy, not fuel
used) per capita of 2.7kW.
The biggest wind farm under construction is around 3MW per turbine.
to generate 160GW of power takes around 53,000 of these turbines.
The latest and greatest wind farm costs around $3billion (£1.5billion)
for 90MW, therefore the total cost of going ?all wind power? would be
£2.6 trillion pounds.
In per capita terms, at a capital cost of £16.67 per watt, that is a
capital cost of £45k per person for total generation capacity requirements.
The average cost of (conventional) generating capacity is quoted here as
$1000 per kilowatt
£500 per kilowatt, or 50p per watt. Contrast that with £16.67 per
watt for the latest greatest windmill project.
Estimated capital costs for nuclear power are somewhat higher ? the
above source cites $2000 per kilowatt for an AGR, or £1 a watt. A
capital cost of a mere £2,700 per capita to build nuclear power stations
for all the UK?s energy needs. 16 times better return on investment than
offshore windmills. Even allowing for ?pro nuclear? bias in the paper
cited, that has to represent an enormous differential in capital cost
with respect to windmills. Decommissioning costs are estimated to be up
to 15% of the above.
Fuel costs are a relatively insignificant part of the total cost of
nuclear power as has been shown earlier ? less than .1p per kWh
currently. Running staffing, maintenance and capital depreciation plus
decommissioning represent the largest part of the energy costs. For
example over a 20 year period at say £1 per watt capital cost, a
straight amortization makes the £1000 per kilowatt spread out over
175200 hours, less than 0.56p per unit (kWh) generated.
In addition Wind power is highly inflexible: when the wind blows you
have more than you want, when it doesn?t you have none. Expecting that
Scotland will be blowing while England is still, is a dangerous
assumption, and would require even more grid investment to carry power
from one part of the country to another.
Nuclear stations have a different problem: they do not like to cope with
highly fluctuating demand.
That means storage for part of the diurnal cycle would be needed for a
100% nuclear electric scenario.
That takes us on to the next bit of analysis. Non fossil fuel transport.
Batteries are available that will satisfy all transport needs (lithium
ion polymer and the like) ? but currently at a high price. However
there is nothing intrinsically difficult about making them - no more so
than a typical lead acid battery at 1/10th the price per unit capacity.
Diesel energy density is about 38MJ/liter..and taking an average tank
of ? say ? 50 liters, then we need a 1400Mj of battery for an ?average?
car..388Kwh. However an electric only vehicle is likely to be around 90%
efficient as compared with an average of 15-25% for a diesel car (not
only is the diesel at best 30% efficient, but other losses ? braking,
idling and so on are present: regenerative braking and zero fuel
consumption at idle apart from radio/aircon etc is likely to get a
better comparable efficiency figure overall) So a similar battery needs
to be around 75kWh for similar range ? 400 miles. In practice for MOST
needs we can go to around half this for reduced range. - about 35kWh.
With this keyed in to off peak charging on an every night basis, the
total transport needs of the country can absorb the electricity at times
when the generating capacity exceeds immediate needs.
Given that the energy spilt between industrial (mainly heating/cooling)
domestic( mainly heating) and transport (mainly heating the air!!) is
broadly equal, we can look at a domestic energy storage situation: Again
these are broad brush strokes, but serves to give an order of magnitude
indication: if each individual has an energy rating of 2.7Kw, and about
a third of that is domestic consumption, then we arrive at an average of
900W/person consumption in the home.
For a 4 person family, to run all day and only use off peak electricity,
we need 16 hours of capacity: say 24 hours capacity 3.6Kwx24hours =
86.4kWh..or a couple of car batteries as described above. In lead acid
terms its 7200Ah at 12v..
Now I found a 200AH truck battery at £142.99 retail
that equates to 36 of those to act as an energy store for a 4 person
household. A shade over £5000. Given the ease with which a new house
could be equipped not with a wet central heating system ? at
£5,000-£10,000 ? but with an electrical one at far lower cost, this is
not an excessive figure: indeed the need for stored hot water would be
eliminated, as the PEAK power output of such a battery would be well in
excess of 100KW...enough to fill a bath or run a couple of showers. One
would probably wire the house as a DC house at 240v with a ?smart?
charger that would charge when ? say ? the voltage rose above a certain
level indicating low load on the national generating capacity. That plus
inverters for legacy AC equipment would enable the house to run for
several days in summer, and at least 8 hours in winter, with no other
power source whatsoever.
Such distributed battery storage, with the cost borne by the user, would
completely solve the daily peak to mean issues of the grid/power station
complex. In addition if electric cars were harmonized to around 240V DC
as well, that would represent an enormous pool of energy storage that
could be used in emergencies. It is accepted that such an uptake of lead
acid batteries would seriously strain the production capacity and actual
lead resources but once in place,, lead batteries are very recyclable.
What about other alternative energies?? windmills are obviously
Well solar power direct is certainly a potential contributor..this article
up with a capital cost requirement of around $1/watt (50p/watt) as
the economic point. Which sits well with previously calculated figures
of a nuclear power station at around £1/W..with a longer life span and
less maintenance..(no need to scrub the algae off the roof panels with
nuclear).. However such technology is a ways off yet, and would
obviously operate at reduced efficiency in winter, when demand for fuel
is at its highest.
we can expect about 50W/sq meter *average* solar energy in the
UK..with a typical conversion efficiency of 10% (and that?s bloody
optimistic) we get just 5W per square meter average out of a solar panel.
So for our 160GW national needs, that?s 32G sq meters..
About 176 kilometres square, or 110 miles square roughly. About twice
the land area currently devoted to agriculture..
Right. Might be easier to plant it with biofuel? Basically what this
shows us is that we actually produce nearly as much heat as we get from
the sun on land by burning fossil fuels..In our climate solar energy
would be ? if the price was right ? cheaper probably than windmills, but
to make any significant impact at all, the area required exceeds even
In fact there is not enough agricultural land area to grow our own food,
let alone fuel, and the solar energy density makes wide scale solar
power a complete non starter as far as any significant contribution goes.
Where does this leave us?
The first point is that at current population levels a ?renewable?
energy policy is simply a non-starter. There is insufficient energy
coming into the country as sunlight to meet our energy needs with any
available 'renewable' technology.
Wind power which essentially uses the oceans as solar collectors, is
around ten times as expensive as any other alternative. It?s only viable
now as a result of massive subsidies.
The UK, and most of Northern Europe, has almost no alternatives between
- continued use of fossil fuels on a massive scale.
- reducing population levels and lifestyles (and energy consumption) to
something approaching pre-industrial levels.
- go for a nuclear electric base solution, augmented by small scale
production from other means. And switch to battery-electric vehicles in
Nothing else is remotely viable when analysed in detail.
All of the current ?energy conservation? measures that are promoted by
governments at best might reduce the total consumption by a few percent
..that figure of 2.7KW per person average power consumption makes
replacing 10 x 60W bulbs that are on perhaps 20% of the time with 10 x
25W bulbs ?90W average saving at best. In a 4 person house using an
average of 10.8kW..and indeed the heating effect of the bulbs would be
lost as well, so in reality probably only a saving of 30-50W against a
total energy burn of 10kW..about 0.3%.
Better insulation MIGHT help ? but whilst energy efficiency of houses
has increased since 1970, per capita domestic heating energy has
increased. Why? Because less people live in large families in flats and
small houses., and more people live in larger spaces. And people travel
Reducing people?s standard of living more than slightly is simply
The final conclusion goes like this.
We cannot sustain the population we now have and anything approaching
the standard of living we have come to expect, without generating more
power than any renewable sources can actually generate, at any cost.
For reasons geopolitical, of resource depreciation, and of climate
change, the continued use of fossil fuels has to be brought down ? not
by a few tenths of a percent, but by a huge percentage- more than 50% -
in the next 100 years or so.
No viable alternative to nuclear power exists. Not for the scale
required, and even that requires significant investment in electricity
distribution and battery technology to become practicable.
However these are at least soluble problems. Using windmills and solar
panels ? at least in N Europe, does not even address the problem. Any
more than government inspired initiatives for CFL light bulbs or
upgrading insulation standards do anything more than provide political
spin to reassure a nervous population that ?something is being done?.
Personally I would of course prefer that nuclear fusion energy was NOT
the only viable solution: perhaps by 2100 it will not be, but in the
context of right here, right now, I can see no other alternative:
Politically the EU is between a rock and a hard place: on one hand the
clamour for climate change measures is deafening, but also the clamour
against nuclear energy. This leaves governments with little alternative
but to simply fudge the issues, come up with inadequate directives, and
throw the hot potatoes a little further into the future.
You will also note that in the proposed viable future, oil/gas companies
have ceased to exist as a significant force. This in itself should be
enough to realise why any so called 'scientific' study hat is funded by
oil companies should be viewede with some scepticism.
- posted 12 years ago