Module 07
Renewable Energy (RE) Technologies & Impacts
(continued)
- Use of RE sources in electricity generation, in transport, and
in other energy consumption modes
- Ecological impacts of RE sources,
and mitigation measures
Prof. R. Shanthini
Feb 11, 2012
RE technology options:
- Hydroelectric
- Solar Photovoltaics (Solar PVs)
- Solar Thermal (Solar T),
also known as Concentrated Solar Power (CSP)
- Wind
- Geothermal
- Marine (Wave and Tidal)
- Biofuels (Biomass, Bioethanol and Biodiesel)
Prof. R. Shanthini
Feb 11, 2012
Biodiesel
Biodiesel can be used in compression ignition engines with
little or no modifications.
Biodiesel is derived from renewable lipid sources, such as
vegetable oil or animal fat.
Biodiesel is a mixture of mono-alkyl esters of long chain fatty
acids.
Prof. R. Shanthini
Feb 11, 2012
Biodiesel production (traditional method)
Biodiesel is made by chemically combining
any natural oil or animal fat (major component of
which is triglyceride)
with an alcohol (methanol / ethanol / iso-propanol)
in the presence of a cataylst (NaOH or KOH)
triglycerids
+
methanol
KOH
methyl
Ester
(biodiesel)
+
glycerol
(glycerin)
This process is known as transestrification.
Prof. R. Shanthini
Feb 11, 2012
Biodiesel production (traditional method)
KOH
Methanol
Glycerol
Triglyceride
Prof. R. Shanthini
Feb 11, 2012
Biodiesel:
mixture of
methyl esters
Transestrification is a reaction of an ester
with an alcohol to form a different ester.
Triglyceride
Prof. R. Shanthini
Feb 11, 2012
Glycerol
Triglyceride to Free fatty acids
Prof. R. Shanthini
Feb 11, 2012
Free fatty acid (FFA) to biodiesel
H2SO4
Free Fatty Acid
Methanol
Methyl ester
Water
This process is known as estrification (which is a
reaction of an acid with an alcohol to form an ester).
NaOH
Free Fatty Acid
Prof. R. Shanthini
Feb 11, 2012
Base
Na
Soap
Water
This process is known as saponification, in
which soap is produced.
Biodiesel feedstock
Vegetable oils:
- Rape seed/Canola (> 80%)
- Soybean (USA, Brazil)
- Cotton seed (Greece)
- Palm (Malaysia)
- Peanut
- Sunflower (Italy, FranceSouth)
- Linseed & Olive (Spain)
- Safflower
- Coconut
- Jatropha (Nicaragua)
- Guang-Pi (China)
Prof. R. Shanthini
Feb 11, 2012
Animal fats:
- Beef tallow (Ireland)
- Lard
- Poultry fats
Waste oils:
- Used frying oils (Austria)
Other feed stocks:
- Algae
Biodiesel production process
(5 to 25% FFA)
Prof. R. Shanthini
Feb 11, 2012
Biodiesel blends used in diesel engines
B2 – 2% biodiesel and 98% petro diesel
B5 – 5% biodiesel and 95% petro diesel
B20 – 20% biodiesel and 80% petro diesel
Prof. R. Shanthini
Feb 11, 2012
http://www.mechanicalengineeringblog.com/tag/biodiesel-chemistry
Biodiesel from algae
Prof. R. Shanthini
Feb 11, 2012
Claimed output of 10,000 gallons of
biodiesel per hectare per year.
Biodiesel from algae
10,000 gallons of biodiesel per hectare per year
= 37854 litres per 2.47 acres per year
= 15325 litres per acre per year
= 15325 / 160 litres per perch per year
= 96 litres per perch per year
= 96 /12 litres per perch per month
= about 8 litres per perch per month
Prof. R. Shanthini
Feb 11, 2012
Claimed output of 10,000 gallons of
biodiesel per hectare per year.
Algae biodiesel life cycle
Algae harvesting
from habitat
Culture
maintenance/storage
Conversion to
biodiesel
Growth in
open pond
Transportation and
distribution
Harvesting
customer
Separation of cell
components
Combustion in
vehicles
Prof. R. Shanthini
Feb 11, 2012
Carbohydrate
and protein
contents
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
Partial treatment
of wastewater
Acquiring
resources of
manufacture
Crude oil
drilling
Prof. R. Shanthini
Feb 11, 2012
Algae harvesting
from habitat
Culture
maintenance/storage
Manufacture /
construction of
open pond
Growth in
open pond
Manufacture /
maintenance of
equipment
Harvesting
Crude oil
refining
Hexane
purification
Separation of cell
components
Carbohydrate
and protein
contents
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
HCl
production
Salt mining
Natural gas
and methane
extraction
Sodium methoxide
Natural gas
and methane
refining
Metal
mining
Salt mining
Prof. R. Shanthini
Feb 11, 2012
Methanol
production
Conversion to
biodiesel
Catalyst
production
NaOH production
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
Acquiring
resources of
manufacture
Crude oil
drilling
Manufacture /
maintenance of
equipment
Crude oil
refining
Transportation and
distribution
customer
Combustion in
vehicles
Prof. R. Shanthini
Feb 11, 2012
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
When harvested, there is 0.05% algae
in wastewater.
It has to be brought to 91% algae in
wastewater (required by the hexane
extraction step).
This is achieved by a dewatering
process (filtration or centrifugation)
followed by drying in a natural gas fired
dryer.
Hexane
purification
Algae dewatering is the
most significant energy sink
in the entire process.
Prof. R. Shanthini
Feb 11, 2012
Algae harvesting
from habitat
Culture
maintenance/storage
Growth in
open pond
Harvesting
Separation of cell
components
Carbohydrate
and protein
contents
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
Prof. R. Shanthini
Feb 11, 2012
Algal lipid
content
(%, w/w)
40
Total energy input
(MJ / 1000 MJ algae
biodiesel)
2,500
30
3,292
20
4,878
15
6,470
10
9,665
5
19,347
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle
In most algae species, there is typically a larger
percentage of carbohydrates than lipids in an algae cell.
With lipid removed to produce biodiesel, the remaining
carbohydrates makes an excellent feedstock for
bioethanol.
Every 24 kg of algal biodiesel produced (one functional
unit,1,000 MJ algae biodiesel), 28.1 kg carbohydrates
and cellulose coproduct are also produced.
With less than 2% lignin, bioethanol processing
becomes more favourable.
Prof. R. Shanthini
Feb 11, 2012
K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Prof. R. Shanthini
Feb 11, 2012
Life-cycle assessment (LCA)
Is it better to use LED lights or CFL lights or incandescent
lights?
Is electric car better than petrol/diesel car?
Is hydroelectricity better than fossil fuel electricity?
Is electricity from coal power is better than electricity from
nuclear power?
How do we answer these questions?
Prof. R. Shanthini
Feb 11, 2012
We could do LCA analysis.
Life-cycle assessment (LCA)
LCA is a tool to assess the potential environmental impacts of
product systems or services at all stages in their life cycle –
from extraction of resources,
through the production
and use of the product
to reuse, recycling
or final disposal.
Prof. R. Shanthini
Feb 11, 2012
Life-cycle assessment (LCA)
- LCA determines the environmental and societal impacts
(damages, in particular) of products, processes or services
through its entire lifecycle.
- Environmental and societal impacts means the impacts of
use of resources as well as the impacts of wastes generated
on the environment and society.
- LCA considers all stages of a process, such as raw material
(resource) extraction, processing and transport,
manufacturing, packaging, distribution, use, and
disposal/recycling.
Prof. R. Shanthini
Feb 11, 2012
Life-cycle assessment (LCA)
LCA is a technique to assess the potential environmental
impacts associated with a product or service throughout
its life cycle, by:
- Defining suitable goal and scope for the LCA study
- Inventory analysis
- Impact assessment
- Interpreting the results
Prof. R. Shanthini
Feb 11, 2012
Life-cycle assessment (LCA)
Impact analysis
provides information
about the kind and
degree of
environmental impacts
resulting from a
complete life cycle of a
product or activity.
Prof. R. Shanthini
Feb 11, 2012
Inventory analysis provides
information regarding
consumption of material and
energy resources (at the
beginning of the cycle) and
releases to the environment
(during and at the end of the
cycle).
Improvement analysis
provides measures that can be
taken to reduce impacts on the
environment or resources.
Source: S. Manahan, Industrial Ecology, 1999
Life-cycle assessment (LCA)
Life-cycle analysis must consider
- selection of materials, if there is a
choice, that would minimise waste
- reusable and recyclable materials
- recyclable components
- alternate pathways for the manufacturing
process or for various parts of it
Prof. R. Shanthini
Feb 11, 2012
Source: S. Manahan, Industrial Ecology, 1999
Life-cycle assessment (LCA)
LCA looks at products or processes from start to finish.
Cradle
Gate
Prof. R. Shanthini
Feb 11, 2012
Life-cycle assessment (LCA)
LCA looks at products or processes from start to finish.
Gate
Grave
Prof. R. Shanthini
Feb 11, 2012
Coffee producer
Cradle
Gate
Grave
Prof. R. Shanthini
Feb 11, 2012
http://www.sustainability-ed.org.uk/pages/look4-1.htm
Life-cycle assessment (LCA)
supply
transport
manufacturing
disposal
Use
packaging
Cradle to Gate
(4 stages)
Prof. R. Shanthini
Feb 11, 2012
Cradle to Grave
(6 stages)
Components of life-cycle assessment:
Prof. R. Shanthini
Feb 11, 2012
Phases in a life-cycle assessment:
Goal and Scope Definition
(Determining boundaries for
study)
Inventory Analysis
(Data on inputs and outputs
quantities for all relevant
processes)
Interpretation
(Major contributions,
sensitivity analysis: what
can be learned from study?)
Impact Assessment
(Contribution to impact
categories, such as energy
consumption, through
normalization and weighing)
Prof. R. Shanthini
Feb 11, 2012
ISO 14040 framework
Phases in a life-cycle assessment:
Prof. R. Shanthini
Feb 11, 2012
ISO 14040 framework
Goal definition and Scoping:
• Level of specificity in the study
– Is the product being analyzed specific to a company or a
plant? (Two different plants producing the same type of
product could have different emission levels, for example)
– Or, will we focus on industrial averages (e.g., impacts of
using recycled aluminum in a design)?
Prof. R. Shanthini
Feb 11, 2012
- Tellus Institute
Goal definition and Scoping:
• Level of accuracy in data collection / analysis
– Should be high if used in driving public policy
– If used in internal decision making for a firm, a reasonable
estimate is generally enough
Prof. R. Shanthini
Feb 11, 2012
- Tellus Institute
Goal definition and Scoping:
• How to display the results. Example: comparing two
products
– Comparison should be made in terms of equivalent use
– Example: bar soap vs. liquid soap; the basis should be an
equal number of hand washings
Prof. R. Shanthini
Feb 11, 2012
- Tellus Institute
An example life-cycle assessment:
Osram LCA for the following products: 1,000 hour lifetime for
incandescent; 10,000 hour for CFL, and 25,000 hour for LED.
Prof. R. Shanthini
Feb 11, 2012
Source: www.osram-os.com
An example life-cycle assessment:
The 1.7 kg microchip:
Environmental implications of the IT revolution
1600 g of fossil fuels
One 32 MB DRAM chip
(weight = 2 gram)
71 g of chemicals
32,000 g of water
700 g of elemental
gases (mainly nitrogen)
by Eric D. Williams, Robert U. Ayres, and Miriam Heller, The 1.7 Kilogram
Microchip: Energy and Material Use in the Production of Semiconductor
Devices. Environmental Science & Technology (a peer-reviewed journal of the
American Chemical Society), 2002, 36 (24), pp 5504–5510
Prof. R. Shanthini
Feb 11, 2012
Source: http://www.enviroliteracy.org/subcategory.php/334.html
An example life-cycle assessment:
Electricity cons.
(use)
4%
Cell Phones
Distribution
0.5%
Disposal
0.5%
Assembly at
NEC
7%
Purchased parts
88%
Prof. R. Shanthini
Feb 11, 2012
Primary Energy Consumption
An example life-cycle assessment:
Distribution
1.0%
Desktop PCs
Disposal
0.2%
Electricity cons.
(use)
39%
Purchased parts
59%
Assembly at
NEC
1%
Prof. R. Shanthini
Feb 11, 2012
Primary Energy Consumption
An example life-cycle assessment:
Most of the energy use occurs in purchased parts
(manufacturing and raw material extraction.)
Remanufacturing is best!
Prof. R. Shanthini
Feb 11, 2012
Primary Energy Consumption
Limitations of LCA: some examples
• Weights given to different impacts
– What is more important? Use of water resources or CO2
emissions?
• Drawing the boundaries
– Cradle to Gate or Cradle to Grave?
– Do we consider supporting activities for the system?
• Example: a warehouse stores the product. Direct
energy consumption for the warehouse should be part
of the system, but emissions associated with garbage
pickup for the facility probability shouldn’t be.
Prof. R. Shanthini
Feb 11, 2012
Life Cycle Assessment (LCA)
43
Limitations of LCA: some examples
• Social and economic impacts
– Environmental impacts are relatively easy to measure, but
socio-economic impacts are difficult to quantify
• Renewable vs. non-renewable resources
• Remanufacturing, recycling, and reuse
– Consideration of recycling makes significant impact, even
though that depends on recycling rates
Prof. R. Shanthini
Feb 11, 2012
Life Cycle Assessment (LCA)
44
Further Resources
• The web has an incredible amount of information on LCA
• For starters, please check the document
“LCA_guide_EPA.pdf” on Angel, which has a more
detailed guide to LCA (by the EPA), and it includes a list
of software vendors
• See http://www.life-cycle.org/
Prof. R. Shanthini
Feb 11, 2012
Life Cycle Assessment (LCA)
45
Life cycle assessment of biodiesel production from
free fatty acid-rich wastes
Biodiesel production systems considered:
- Acid-catalyzed esterification followed by alkali-catalyzed
transesterification of waste vegetable oils (used cooking oil)
- Esterification and transesterification of beef tallow
- Esterification and transesterification of poultry fat
- Acid-catalyzed in-situ transesterification of sewage sludges
Prof. R. Shanthini
Feb 11, 2012
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Life cycle assessment of biodiesel production from
free fatty acid-rich wastes
Impact potentials evaluated:
- Global warming (GWP)
in kg CO2 eq.
- Acidification (AP)
in kg SO2 eq.
- Eutrophication (EP)
in kg PO43- eq.
- Ozone layer depletion (ODP)
in mg CFC-11 eq.
- Photochemical oxidant formation (POFP)
in kg C2H4 eq.
- Cumulative non-renewable energy demand (CED) in GJ eq.
Prof. R. Shanthini
Feb 11, 2012
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Biodiesel production system
Other
inputs
FFA-rich waste
Transportation
Electricity
production
Thermal
energy
production
Water suppy
Chemicals
production
rendering
Wastes
Transportation
Esterification
Trans-esterification
Waste
management
Transportation
Biodiesel
Prof. R. Shanthini
Feb 11, 2012
Glycerol
Other outputs
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Other
inputs
Biodiesel production system (for sewage sludges)
FFA-rich waste
Electricity
production
Wastes
Thermal
energy
production
Water suppy
Chemicals
production
Trans-esterification
Waste
management
Transportation
Biodiesel
Prof. R. Shanthini
Feb 11, 2012
Glycerol
Other outputs
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel
Materials
waste
vegetable
oils
rendered
beef
tallow
rendered
poultry
fat
dried
sewage
sludge
Lipid
feedstock
1205
1015
1013
10,000 kg
Methanol
112.67
113.32
99.00
670.18 kg
Sulphuric acid
0.15
-
-
76.35
kg
Calcium oxide
0.10
-
-
-
kg
Water
56.08
71.32
32.00
0.88
kg
9.80
4.00
5.00
-
kg
11.00
12.00
-
kg
-
-
kg
7.00
-
kg
-
76.28
kg
Sodium
hydroxide
Sodium methoxide
Phosphoric acid
-
7.95
Hydrogen chloride
Hexane
Prof. R. Shanthini
Feb 11, 2012
-
6.00
-
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel
Energy
waste
vegetable
oils
rendered
beef
tallow
rendered
poultry
fat
dried
sewage
sludge
Thermal
(rendering)
1628.93
-
-
-
MJ
Electrical
(rendering)
133.12
-
-
-
kWh
Thermal
(esterification)
222.30
175.94
90.04
-
MJ
Electrical
(esterification)
31.43
28.93
10.08
-
kWh
Thermal
(transesterification) 1650.84
Electrical
(transesterification)
Prof. R. Shanthini
Feb 11, 2012
20.34
1733.48
1886.96
30.36
28.98
2542.95 MJ
28.47 kWh
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel
Transport
(by lorry)
waste
vegetable
oils
To
rendering
plant
187.76
-
-
-
t km
To
biodiesel
plant
291.31
293.44
292.76
-
t km
Prof. R. Shanthini
Feb 11, 2012
rendered
beef
tallow
rendered
poultry
fat
dried
sewage
sludge
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of output data for the production of 1 t Biodiesel
Materials
waste
vegetable
oils
Biodiesel
1.00
1.00
Glycerol
102.21
115.64
Salts to
landfill
16
rendered
beef
tallow
9
rendered
poultry
fat
dried
sewage
sludge
1.00
1.00
t
109.00
129.05 kg
10
-
kg
26.00
-
kg
Hazardous
liquid waste
30.46
24.00
Organic
waste to
landfill
85.40
-
-
-
kg
-
-
2
t
Sludge
Prof. R. Shanthini
Feb 11, 2012
-
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Global Warming Potential
(kg CO2 eq per GJ of energy supply)
100
80
60
40
20
Prof. R. Shanthini
Feb 11, 2012
ie
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J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Acidification Potential
(kg SO2 eq per GJ of energy supply)
0.6
0.5
0.4
0.3
Prof. R. Shanthini
Feb 11, 2012
So
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0.2
0.1
0
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Prof. R. Shanthini
Feb 11, 2012
So
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0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
fa
ts
Eutrophication Potential
(kg PO4 ions eq per GJ of energy supply)
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Ozone layer Depletion Potential
(kg CFC-11 eq per GJ of energy supply)
12
10
8
6
4
Prof. R. Shanthini
Feb 11, 2012
So
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ea
n
R
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es
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2
0
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Photochemical Oxidant Formation Potential
(kg C2H4 eq per GJ of energy supply)
0.06
0.05
0.04
0.03
0.02
Prof. R. Shanthini
Feb 11, 2012
So
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ea
n
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ls
0.01
0
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels
Prof. R. Shanthini
Feb 11, 2012
So
yb
ea
n
R
ap
Lo
es
w
ee
-s
ul
d
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1.4
1.2
1
0.8
0.6
0.4
0.2
0
fa
ts
Cumulative Non-renewable Energy Demand
(GJ eq per GJ of energy supply)
J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Prof. R. Shanthini
Feb 11, 2012
Prof. R. Shanthini
Feb 11, 2012
Prof. R. Shanthini
Feb 11, 2012
Prof. R. Shanthini
Feb 11, 2012