Transcript electrical

Sustainable Resource Technology NOTE 7
(Principles in Sustainable Energy Technologies)
Joonhong Park
Yonsei CEE Department
2015. 11. 18.
Energy Conversion Efficiencies
Chemical
Energy
(fossil
fuels etc.)
70-95 %
100 %
Thermal
Energy
(heat)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Cogeneration/CHP
Chemical
Energy
(fossil
fuels etc.)
Recovery of Waste
Heat (Combined
Heat and Power)
70-95 %
100 %
Thermal
Energy
(heat)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Solar Power
Solar Power
100 %
Thermal
Energy
(heat)
Recovery of Waste
Heat (Combined
Heat and Power)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Solar Power Systems
• Low temperature
• High temperature
- Dish collectors
- Stirling engines
- Power towers
- Trough collectors
Sun-induced Heat
Sun-induced Heat
100 %
Thermal
Energy
(heat)
Recovery of Waste
Heat (Combined
Heat and Power)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Operational principle of an ocean
thermal energy converter
(pilot scale)
Electric power generator
Ammonia
Vapor
Warm
Water
(25oC)
Turbine
Condenser
Evaporator
Cold
Water
(5oC)
Ammonia
Liquid
Pump
Photovoltaics (Solar Light)
Sun
light
Turning sunlight into
Electricity with high efficiency
at low cost using common
materials.
Photovoltaics
90-95 %
Thermal
Energy
(heat)
100 %
(n-p junction in a solar cell)
85-95 %
Mechanical
energy
Electrical
energy
90-95 %
Wind power
100 %
Thermal
Energy
(heat)
Wind power
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Horizontal axis wind turbine: rotor diameter, machine rating,
rotational speed & number of blades, the generator
Environmental impacts: electromagnetic interference, ecological impact, noise
Wave power
100 %
Thermal
Energy
(heat)
Wave power
85-95 %
Mechanical
energy
Electrical
energy
90-95 %
Global energy densities: New Zealand (100), South Africa (70),
North east France (70), Korea-Japan ( 15)
Power is a function of wave height (h)
Onshore devices, Offshore devices (Salter Duck, Pelamis)
Tidal and small-scale hydropower
100 %
Thermal
Energy
(heat)
Tidal and small-scale
hydropower
85-95 %
Mechanical
energy
Electrical
energy
90-95 %
Tidal stream
Small-scale hydropower
Biomass
C-fixation
Chemical
Energy
(Biomass)
Recovery of Waste
Heat (Combined
Heat and Power)
CO2
70-95 %
Oxidation
100 %
Thermal
Energy
(heat)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Geothermal
Geothermal
100 %
Thermal
Energy
(heat)
Recovery of Waste
Heat (Combined
Heat and Power)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Environmental impact?
Fast Breeder & Fusion
Nuclear
Energy
Recovery of Waste
Heat (Combined
Heat and Power)
Fast Breeder
Fusion
70-95 %
100 %
Thermal
Energy
(heat)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Fast Breeder (Fission)
100 fissions
292 neutrons produced
39
lost
32 by Pu
121 by 238U
84 in Pu
13 in 238 U
3 in 235 U
A variety of thermal reactors
Type
Thermal Coolant Moderator
Power
(MW)
Core
Vol. PD Fuel
Volume (MW/
Rating
(m3)
m3)
(MW/
tonne)
Exit
Coolant
Temp
(oC)
Magnox 2251875
CO2
Graphite
4492166
0.5-0.87 2.23.15
400
AGR
1500
CO2
Graphite
550
2.5
11.2
650
CANDU
3425
D2O
D2O
280
12.2
26.4
293
PWR
3800
H2O
H2O
40
95
38.8
332
BWR
3800
H2O
H2O
75
51
24.6
290
RBMK
3140
H2O
Graphite
765
4.1
15.4
-
Fast
Breeder
1000
Liquid
Na
None
1.5
400
150
-
Fusion
Nuclear
Energy
Recovery of Waste
Heat (Combined
Heat and Power)
Fusion
100 %
70-95 %
Thermal
Energy
(heat)
20-40 %
85-95 %
Mechanica
l energy
Electrical
energy
90-95 %
Potential uses of Fusion technology
NUCLEAR
KINETIC
Fast
Fission
Fusion
Wind
SOLAR
Geothermal
(radioactivity)
Thermal
Fission
Wave
Mechanical
THERMAL
Electricity
Heat
ELECTRICAL
Hydro
Tidal
Geothermal
(original accretion)
Biomass
Fossil
Fuels
GRAVITATIONAL
Hydrogen
CHEMICAL
Batteries
Fuel Cells
Chemical
Energy
Fuel Cells
90-95 %
Thermal
Energy
(heat)
100 %
85-95 %
Mechanical
energy
Electrical
energy
90-95 %
The current uses of unsustainable energy technologies. How
about the potential uses of sustainable energy technologies?
Sustainability
• General Definition: meeting the needs of the present generation without
compromising the ability of future generation to meet their own needs.
• Don’t do these: exhausting a natural resource, leaving large costs for future
generations or doing irreversible harm to the planet.
• An energy technology is considered sustainable if:
1. It contributes little to manmade climate change.
2. It is capable of providing power for many generations w/o
significant reduction in the size of the resource, and
3. It does not leave a burden to future generation.
☞ It is very difficult to say if an energy technology is truly sustainable or not.
21
The major energy transformations, fuels and groupings
NUCLEAR
KINETIC
Fast
Fission
Fusion
Wind
SOLAR
Geothermal
(radioactivity)
Thermal
Fission
Wave
Mechanical
THERMAL
Electricity
Heat
ELECTRICAL
Hydro
Tidal
Geothermal
(original accretion)
Biomass
Fossil
Fuels
GRAVITATIONAL
Hydrogen
CHEMICAL
Batteries
Unsustainables vs. Sustainables
Unsustainable : Fossil fuels, Large-scale hydropower,
Thermal unclear reactors
Sustainable : Solar, Wind, Wave, Tidal, Small-scale
Hydropower, Biomass, Geothermal, Fast nuclear reactors,
Nuclear fusion
☞ Do you accept the classification?
☞ What are your rationales for it?
23
Capability to provide energy for many generations
Warming
3
Halocarbons
2
Aerosols
N2O
CH4
1
CO2
Tropospheric
ozone
Fossil
Fuel
Burning
(Black C)
Mineral
Dust
Solar
0
Stratospheric
ozone
-1
Cooling
Radiative Force (Wm-2)
Radiative Forcing &
Global Temperature Change
Fossil Biomass
Fuel Burning
Sulfate
Burning
(Organic C)
Land use
(albedo)
-2
High
Very Low
Level of Scientific Understanding
The final change in global mean temperature: dT = Ø * ΣdF
Ø is the proportionality constant; dF is the change in radiative forcing
(see equations at p. 115
25
Other Concerns
General Pollution
Acid Rains
Injuries and fatalities
Land use
Energy paybacks
External costs and sustainability
General Pollution Concerns
Source
Potential causes for concern
Oil
Global climate change, air pollution by vehicles, acid rain, oil spills, oil rig
accidents
Natural gas
Global climate change, methane leakage from pipes, methane explosions, gas
rig accidents
Coal
Global climate change, acid rain, environmental spoliation by open-cast
pollution, mining accidents, health effects on miners
Nuclear power
Radioactivity, misuse of fissile and other radioactive material by terrorists,
proliferation of nuclear weapons, land pollution by mine tailings, health effects
on uranium miners
Biomass
Effect on landscape and biodiversity, groundwater pollution due to fertilizers,
use of scarce water, competition with food producing
Hydroelectricity
Displacement of populations, effect on rivers and groundwater, dams (visual
intrusion and risk of accident), seismic effects, downstream effects on agriculture,
methane emissions from submergend biomass
Wind power
Visual intrusion in landscapes, noise, bird strikes, interference with
telecommunications
Tidal power
Visual intrusion and destruction of wildlife habitat, reduced dispersal of effluents
(these concerns apply manly to tidal barrages, not tidal current turbines)
Geothermal energy
Release of polluting gases (SO2, H2S, etc), grounwater pollution by chemicals
including heavy metals, seismic effects
Solar energy
Sequestration of large land areas (in the case of centralized plant), use of toxic
materials in manufacture of some PV cells, visual intrusion in rural and urban
environments
Global loading from various pollutants
and human disruption
Insult
Natural
Baseline
(tonnes/
year)
Human
Disruption
Index
Commercial
Energy
Supply
Traditional
Energy
Supply
Agriculture
Manufacturing,
other
Lead emission to air
12,000
18
0.41
negligible
negligible
0.59
Oil addition to oceans
200,000
10
0.44
negligible
negligible
0.56
Cadmium to air
1,400
5.4
0.13
0.05
0.12
0.70
Sulphur to air
31 mil
2.7
0.85
0.005
0.01
0.13
Methane flow to air
160 mil
2.3
0.18
0.05
0.65
0.12
Nitrogen fixation
140 mil
1.5
0.30
0.02
0.67
0.01
Mercury emission to air
2,500
1.4
0.20
0.01
0.02
0.77
N2O flows to air
33 mil
0.5
0.12
0.08
0.80
negligible
Particulate to air
3,100 mil
0.12
0.35
0.10
0.40
0.15
Non-methane
hydrocarbon to air
1 billion
0.12
0.35
0.05
0.40
0.30
Carbon dioxide to air
150
billion
0.05
0.75
0.03
0.15
0.07
Acid Rain: Carbonate system
Acid Rain: SOx and NOx
SO2(g) + H2O  H2SO3
2SO2(g) + O2  2SO3 (g)
SO3(g) + H2O  H2SO4
2NO2 (g) + H2O  HNO2 + HNO3
Strong vs Weak Acids
31
SO2 and NOx Emissions of Energy Technologies
Technology
SO2 t/TWh
NO2 t/TWh
Hydro with reservoir
7
150
Diesel (0.25% S)
1285
310-12,000
Heavy oil (1.5% S) without
scrubbing
8013
1,300-2,000
Hydro run-of-river
1
120
Coal (1%S) w/o scrubbing
5274
700-5,000
Coal with SO2 scrubbing
104
690-5,000
Nuclear
3
150
Natural gas
314
77-1,500
Fuel cell
470
-
Biomass plantation
26
1,100-2,500
Sawmill waste
26
69-1,900
Wind power
69
77-130
PV
24
150
Land use
Technology
Km2 per TWh
(min. approx.)
Km2 per TWh
(max. approx.)
Hydro with reservoir
0
200
Hydro run-of-river
1
5
Coal
4
10
Nuclear
0.5
5
Biomass plantation
533
2200
Sawmill waste
1
3
Wind power
25
115
PV
30
45
Energy Payback
Technology
Energy output/
Energy input
Hydro with reservoir
205
Hydro run-of-river
206
Coal(1%S) without SO2 scrubbing
7
Coal (2%) with SO2 scrubbing
5
Nuclear
16
Natural gas
5
Fuel cell
3
Biomass plantation
5
Sawmill waste
27
Wind power
80
PV
9
External cost (Externalities)
Externality: the cost for pollutant etc. that the technology creates.
Summarized List of Factors to be considered
when examining sustainability
 Potential sustainable energy sources
 Global change (especially GHG emissions)
 General Pollution (water, soil/groundwater, ocean, air, wastes)
 Acid Rains
 Injuries and fatalities
 Land use
 Energy paybacks
Strategy to Feasible Estimation:
Energy paybacks vs. External costs vs. Sustainability
(It may be difficult to estimate internal cost of a future technology)
Discussion: hydro-electro-power with a reservoir
vs. with a run-off-river
 Potential sustainable energy sources
 Global change (especially GHG emissions)
 General Pollution (water, soil/groundwater, ocean, air, wastes)
 Acid Rains
 Injuries and fatalities
 Land use
 Energy paybacks
Energy paybacks vs. External costs vs. Sustainability