arthur williamson. we have become dependent on fossil fuel we are using fossil fuel at an...

Arthur Williamson

• We have become dependent on fossil fuel

• We are using fossil fuel at an unsustainable rate

• Burning fossil fuel is producing greenhouse gases which lead to climate change which may become intolerable

The great Nuclear

reactor in the sky

Earth300K

Radiation from sunAt 6000K

Re-radiation from earth to space at 0K

Energy input from sun =1.3 x 1017 watts

Energy reaching earth’s surface = 1.0 x 1017 watts = 100 000 TW

Intensity at earth’s surface = 1000 watts/square metre

What Happens To It?

• Reflection back into space 25%

• Absorbed (to low temp thermal) 67%

• Evaporation 32%

• Wind and Waves 0.25%

• Photosynthesis 0.03%

• Total energy = 3 x 1020 J/yr

• Average power =10TW

• Fraction that is oil = 33%

SOLAR ENERGY SOLAR ENERGY FALLING ON EARTH FALLING ON EARTH

IS IS

10 000 TIMES10 000 TIMES

MANKIND’S NEEDSMANKIND’S NEEDS

Energy falling on NZ

160W/square metre

130 000 000 PJ/yr

Primary energy 750 PJ/yr

Consumer energy 550PJ/yr

Average energy per day for each month (kWh/square metre)

For ChristchurchMonth Horizontal

surface

40 deg inclination

January 5.98 5.47

February 5.45 5.53

March 3.98 4.76

April 2.80 4.14

May 1.78 3.18

June 1.38 2.74

July 1.51 2.78

August 2.53 4.07

September 3.29 4.18

October 4.86 5.21

November 6.27 5.92

December 6.98 6.18

Mean Value 3.9 4.5

• Transport 38%

• Industrial 30%

• Residential 12%

Primary energy (NZ)

• Oil 33%

• Gas 32%

• Hydro 10%

• Geothermal 11%

• Coal 7%

• Wood 5%

• Other 2%

Consumer Energy by Fuel(NZ)

• Oil 53%

• Electricity 25%

• Gas 7%

• Wood 6%

• Coal 6%

• Geothermal 3%

Electricity sources

• Hydro 56%

• Gas 30%

• Geothermal 7%

• Coal 4%

• Other 3%

• WIND

• HYDRO POWER

• SOLAR THERMAL ENERGY

• PHOTOVOLTAIC

• PHOTOSYNTHESIS

Windflow turbines

• WIND

• HYDRO POWER

• SOLAR THERMAL ENERGY

• PHOTOVOLTAIC

• PHOTOSYNTHESIS

• WIND

• HYDRO POWER

• SOLAR THERMAL ENERGY

• PHOTOVOLTAIC

• PHOTOSYNTHESIS

150 MW Kramer Junction

Mojave Desert California

SOLAR1

Now abandonned

Power Tower Spain 11 MW

Sandia 25kW Stirling engine

ELECTROLYSIS

PHOTOTHERMAL

PHOTOCHEMICAL

WATER SPLITTING

• WIND

• HYDRO POWER

• SOLAR THERMAL ENERGY

• PHOTOVOLTAIC

• PHOTOSYNTHESIS

25mw SOLAR PV Spain 2008

1.5MW South Germany cadmium telluride

Small scale systems Arthur’s Pass

• WIND

• HYDRO POWER

• SOLAR THERMAL ENERGY

• PHOTOVOLTAIC

• PHOTOSYNTHESIS

Factors to be considered

• Low overall effectiveness- 0.1%

• Choice of plant type -oil,cellulose, starch, sugar

• Method of conversion

• Competition with food

PHOTOSYNTHESIScycle times

• COAL AND OIL 100 MILLION YR

• TREES 30-50 YR

• CROPS ANNUAL

• ALGAE CONTINUOUS

CONVERSION OF BIOMASS

• DIRECT COMBUSTION

• CONVERSION TO ALCOHOL

• EXTRACTION OF VEGETABLE OIL

• FERMENTATION TO BIOGAS

CONVERSION OF BIOMASS

• DIRECT COMBUSTION

• CONVERSION TO ALCOHOL

• EXTRACTION OF VEGETABLE OIL

• FERMENTATION TO BIOGAS

CONVERSION OF BIOMASS

• DIRECT COMBUSTION

• CONVERSION TO ALCOHOL

• EXTRACTION OF VEGETABLE OIL

• FERMENTATION TO BIOGAS

CONVERSION OF BIOMASS

• DIRECT COMBUSTION

• CONVERSION TO ALCOHOL

• EXTRACTION OF VEGETABLE OIL

• FERMENTATION TO BIOGAS

Yields

• Beet alcohol 5000L/ha yr

• Canola Diesel 1000L/ha yr

EROEIEnergy Return on Energy Invested

• Trees as fuel for combustion 30

• Gorse 30

• Beet alcohol 1.5?

• Canola for diesel 1.5?

• PETROL / ALCOHOL 2 000 000 ha

• DIESEL/BIODIESEL 6 000 000 ha

CONTEXTto feed 4 000 000

• TO FEED 4 000 000

• If we were vegan ABOUT 500 000 ha

• For meat and 3 veg ABOUT 1 500 000 ha

• HOW MUCH HAVE WE GOT?

• ABOUT 13 5000 000 ha

What if we opt for a wood fired thermal power plant

• This could run as baseload

• So we need 1000MW continuous

• Area required = 300 000 -500 000 ha