Post on 28-Mar-2015
Climate Change and our insatiable appetite for energyAre we being Fair?
Sunday 7th May 2006
Keith Tovey (杜伟贤 ) M.A., PhD, CEng, MICE, CEnvHSBC Director of Low Carbon Innovation: School of Environmental SciencesLay Chairman, Norwich East DeaneryCRed
• In UK each person is consuming energy at a rate of
5kW
• In USA it is 10 kW
1/20th or World’s Population consumes 25% of all energy
• In Europe it is 5.7 kW
• Globally it is around 2kW
• ENERGY Consumption > Carbon Dioxide > Global Warming
Climate Change and our insatiable appetite for energy
• This series will look at the Environment, Climate Change and Global Warming.– Is it natural– It is man made– What can be done about it?
• Today’s talk will review Climate Change and then examine the history of energy use.
• Next Week we will go on to consider the hard choices facing us
• Then: what can we do about it?• what should we as Christians do about it?
Keith Tovey (杜伟贤 ) M.A., PhD, CEng, MICEHSBC Director of Low Carbon Innovation: School of Environmental SciencesLay Chairman, Norwich East DeaneryCRed
Climate Change and our insatiable appetite for energy
0 1000 1500 2000 2500500
Year
En
ergy
Con
sum
pti
on
Nuclear Fusion ??
Climate Change and our insatiable appetite for energy
We are currently using our resources unsustainably and unfairly
Future Global Warming RatesConcentration of C02 in Atmosphere
300
310
320
330
340
350
360
370
380
1960 1965 1970 1975 1980 1985 1990 1995 2000
(ppm
)
Total winter precipitation Total summer precipitation
Source: Tim
Osborne, C
RU
Change in precipitation 1961-2001
Climate Change and our insatiable appetite for energy
1.0
0.5
0.0
-0.51860 1880 1900 1920 1940 1960 1980 2000T
emp
erat
ure
Ris
e (o C
)
1.0
0.5
0.0
-0.51860 1880 1900 1920 1940 1960 1980 2000
Tem
per
atu
re R
ise
(o C)
1.0
0.5
0.0
-0.51860 1880 1900 1920 1940 1960 1980 2000
Tem
per
atu
re R
ise
(o C)
Source: Hadley Centre, The Met.Office
actual
actual
actual
predicted
predicted
predictedIs Global Warming man made?
Prediction: Anthropogenic only
Not a good match between 1920 and 1970
Prediction: Natural only
good match until 1960
Prediction: Natural and Anthropogenic
Generally a good match
Predictions include:
• Greenhouse Gas emissions
• Sulphates and ozone
• Solar and volcanic activity
Climate Change: Arctic meltdown 1979 - 2003
• Summer ice coverage of Arctic Polar Region– Nasa satellite
imagery
Source: Nasawww.nasa.gov/centers/goddard/news/topstory/2003/1023esuice.html
•20% reduction in 24 years20031979
CRed
Climate Change and our insatiable appetite for energy
In 1974 Bramber Parish Council decided to go without street lighting for three days as a saving.
( this was during a critical power period during a Miner’s Strike).
Afterwards, the parish treasurer was pleased to announce that, as a result electricity to the value of £11.59 had been saved.
He added, however, that there was a bill of £18.48 for switching the electricity off and another of £12.00 for switching it on again.
It had cost the council £18.89 to spend three days in darkness.
An example of where saving resources and money are not the same
Climate Change and our insatiable appetite for energy
From the Independent
29th January 1996
similar warning have been issued in technical press for this winter
What is wrong with this title?
Climate Change and our insatiable appetite for energy
• No shortage of energy on the planet
• Potential shortage of energy in the form to which we have become accustomed.
Fossil fuels
• FUEL CRISIS.
THE ENERGY CRISIS - The Non-Existent Crisis
Climate Change and our insatiable appetite for energy
• ~ 15% of energy derived from food used to collect more food to sustain life.
+ energy used for
making clothing, tools, shelter• Early forms of non-human power:-
• 1) fire• 2) animal power
HISTORICAL USE OF ENERGY up to 1800
• OTHER ENERGY FORMS HARNESSED
1) Turnstile type windmills of Persians
2) Various water wheels (7000+ in UK by 1085)
3) Steam engines (?? 2nd century AD by Hero)
4) Tidal Mills (e.g. Woodbridge, Suffolk 12th Century)
Early Wind Power Devices
C 700 AD in Persia
•used for grinding corn
•pumping water
•evidence suggests that dry valleys were “Dammed” to harvest wind
LONDON - late 13th /early 14th Century
Shortage of timber for fires in London Area
Import of coal from Newcastle by sea for poor
Major environmental problems -high sulphur content of coal
Crisis resolved - The Black Death.
1.4 The First Fuel Crisis
UK - Late 15th/early 16th century
Shortage of timber - prior claim for use in ship-
building
Use of coal became widespread -even eventually for
rich
Chimneys appeared to combat problems of smoke
Environmental lobbies against use
Interruption of supplies - miner's strike
Major problems in metal industries led to many patents
to produce coke from coal (9 in 1633 alone)
1.5 The Second Fuel Crisis:-
Problems in Draining Coal Mines and Transport of coal
> threatened a third Fuel Crisis in Middle/late 18th Century
Overcome by Technology and the invention of the steam engine by Newcommen.
a means of providing substantial quantities of mechanical power which was not site specific (as was water power etc.).
NEWCOMMEN's Pumping Engine was only 0.25% efficient
Problems in Draining Coal Mines:
WATT improved the efficiency to 1.0%
Initially:
• Boiler valve closed• Injector valve closed
Open boiler valve
Steam push piston up and pumping rod down
At top of stroke
• Close boiler valve• Open injector valve
Water sprays in and condenses steam creating a vacuum
This “sucks” piston down and pulls pumping rod up with water.
Problem: Cylinder is continually cooled and warmed
The Newcomen Engine
9. Elementary Thermodynamics - Watt Engine.
Watt Engine
1) Cylinder is always warm
2) cold water is injected into condenser
3) vacuum is maintained in condenser so “suck” out exhaust steam.
4) steam pushes piston down pulling up pumping rod.
Higher pressure steam used in pumping part of cycle.
NUCLEAR
CHEMICAL - fuels:- gas, coal, oil etc.
MECHANICAL - potential and kinetic
ELECTRICAL
HEAT - high temperature for processes
- low temperature for space heating
• All forms of Energy may be measured in terms of Joules (J),
• BUT SOME FORMS OF ENERGY ARE MORE EQUAL THAN OTHERS
1.8 Forms of Energy
Energy does not usually come in the form needed:
convert it into a more useful form.
All conversion of energy involve some inefficiency:-
Physical Constraints (Laws of Thermodynamics)
can be very restrictive
MASSIVE ENERGY WASTE.
This is nothing to do with our technical incompetence. The losses here are frequently in excess of 40%
ENERGY CONVERSION
Technical Limitations
(e.g. friction, aero-dynamic drag in turbines etc.) can be improved, but losses here are usually less than 20%, and in many cases around 5%.
Some forms of energy have low physical constraints converted into another form with high efficiency (>90%).
e.g. mechanical <--------> electrical mechanical/electrical/chemical -----------> heat
Other forms can only be converted at low efficiency
e.g. heat ------------> mechanical power - the car!
or in a power station
ENERGY CONVERSION
USE MOST APPROPRIATE FORM OF ENERGY FOR NEED IN HAND.
e.g. AVOID using ELECTRICITY for
• LOW TEMPERATURE SPACE heating• Hot Water Heating• Cooking (unless it is in a MicroWave).
ENERGY CONVERSION
HEATING - space and hot water demand
(80%+ of domestic use excluding transport)
LIGHTING
COOKING
ENTERTAINMENT
REFRIGERATION
TRANSPORT
INDUSTRY
- process heating/ drying/ mechanical power
• IT IS INAPPROPRIATE TO USE
ELECTRICITY FOR SPACE HEATING
WHAT DO WE NEED ENERGY FOR?
HIGH GRADE:
- Chemical, Electrical, Mechanical
MEDIUM GRADE: - High Temperature Heat
LOW GRADE: - Low Temperature Heat
• All forms of Energy will eventually degenerate to Low Grade Heat
• May be physically (and technically) of little practical use - i.e. we cannot REUSE energy which has been degraded
- except via a Heat Pump.
GRADES OF ENERGY
So where does it all go?
Climate Change and our insatiable appetite for energy
Per Capita Consumption in Watts ~ 5 kW
• Transport Energy use has risen 10.5% in last decade
• Domestic use has risen by over 10%
1970 1980 1990 2002Domestic 816 882 902 1060Transport 623 786 1076 1207Industry 1379 1069 855 769Other 411 414 425 442
Conversion 1712 1565 1745 1844
Total 4942 4716 5004 5321
Non-Energy 240 165 249 241
• Consumption is ~ 5 kW per capita
• Industrial consumption has declined
• Transport consumption has increased
UK Energy Consumption
Domestic consumption has remained static.
Despite significant improvements to insulation
Increased Population: decreased household size: more convenience appliances: digital television
7. UK Energy Consumption 1990 - 2002
0
1000
2000
3000
4000
5000
6000
Wat
ts p
er C
apit
a
1990 1992 1994 1996 1998 2000 2002
Non-Energy
Conversion
Other
Domestic
Transport
Industry
• Despite much improved insulation standards
• Domestic Energy use has remained static
POTENTIAL OF ENERGY RESOURCES
CURRENT AND PROJECTED USAGE
Projected Saturation Population in 2050 -- 10000 M consumption averages current UK value Requirement in 2050 = 50 TW i.e. 5 x 1013 W.consumption reaches current USA value Requirement in 2050 = 100 TW
i.e. 10 times current demand
Range of forecasts 20 - 100 TW with a likely valuein range 30 - 50 TW (say 40 TW).
Country Energy Requirement
Population Per Capita
World 12.0 TW 6000 M 2.0 kW
USA 3.0 TW 300 M 10.0 kW
Europe 2.0 TW 350 M 5.7 kW
UK 0.3 TW 60 M 5.0 kW
What impact are you having?
• We need to establish benchmarks– Take meter readings when you get home– Take them before you come next week– Keep a record of your petrol/diesel consumption
Climate Change and our insatiable appetite for energy
• Next Week– The Hard Choices facing us
Climate Change and our insatiable appetite for energy
Two questions to discuss
• Who should be responsible for combating Global Warming?• The Government ?• We, as individuals ?• Some one else – if so who?
• How can we even stabilise our consumption? • The Egalitarian Principle?
•Should we all have a fair and equal share of the world’s resources? • > richer countries use less• > poorer countries allowed to consume more
• Eventually all consume the same?
• Should those who already have high consumption be allowed to continue at the expense of those less fortunate?
The Newcomen Engine
Newcomen Engine
pushes piston up
3) At end of stroke, close steam value open injection valve
(and pumping rod down)
4) Water sprays in condenses steam in cylinder creating a vacuum and sucks piston down - and pumping rod up
2) Open steam valve
1) Boil Water > SteamProblem:
Cylinder continually is cooled and heated.