www.jrc.ec.europa.eu

Sustainability of advanced biofuels

Luisa Marelli

European Commission, Joint Research Centre,

Institute of Energy and Transport (IET) (Ispra,

VA, Italy)

Energy and Climate Challenges

The RED 2020 targets:� decrease energy consumption by 20%

� increase the share of renewables to 20%

(10% renewable energy in transport)

Energy and climate package post-2020� 40% GHG reduction in 2030

� Calls for a range of alternative fuels for 2030, with special focus on 2G

and 3G biofuels

� Wide coordination for large scale deployment of alternative fuels

� Stable policy framework to attract investments

NEW Energy Union – Sustainable Low-carbon economy � Alternative fuels and clean vehicles

� Road transport and Renewable Energy package

� Achieve the 40% GHG reduction target

Why promote advanced biofuels?

329 March 2015

Rural Development (Pillar II of EU CAP)• Rural economies benefit from sustainable utilisation of biomass

• Key RD measures in CAP: “Facilitating the supply and use of

renewable sources of energy, of byproducts, wastes, residues and

other non-food raw material for purposes of the bio-economy”

• RD policy to enable rural areas to benefit from RE technology,

including advanced biofuels

Diversification of sources for transport fuels� EU transport sector mainly dependent on fossil fuels

� A critical challenge: 80% reduction in GHG emissions in 40 years (Energy

Roadmap 2050)

� Biofuels are one of the few options to reduce GHG emissions in

transport

4

• Concerns on environmental impacts of 1G biofuels (food-based) calls for

fast transition to 2G and 3G biofuels

• High supply chain GHG emissions savings can be achieved

Notes:

OD = Open storage of digestate;

CD = Closed storage of digestate;

OGC = Off-gas combusted;

OGV = Off-gas vented;

References:

[1] JRC EUR 26696 EN, 2014;

[2] Well-to-Wheels v.4a, 2014.

Why promote advanced biofuels?

529 March 2015

1. Biofuels 1. Biofuels 1. Biofuels 1. Biofuels from wastes and residuesfrom wastes and residuesfrom wastes and residuesfrom wastes and residues

Biofuels from wastes and residues:

• Abundant, relatively cheap and widespread

• No competition with food or land

• Wastes have no or low iLUC

• Valorization of waste streams

Mobilization of wastes and residues is essential but the impacts (environmental/economic) of

increased removal should be carefully assessed

Materials and methodsMaterials and methodsMaterials and methodsMaterials and methods

Four materials:

1. Cereal straws

2. Cattle/Pig slurry and manures

3. Logging residues

4. Pruning residues

629 March 2015

Potential effects:

1. Non – Bioenergy uses (baseline)

2. Removal effects

3. Displacement effects

Environmental impacts:

1. Total GHG balance

2. Soil Organic Carbon

3. Nutrient pools

4. Soil health and productivity

5. Direct N2O, CH4 emissions

6. Pests, diseases and odours

7. Biodiversity

8. Water

Straw

� Harvestable straw: ∼50% of ABG residues

� 25-30% of straw in EU available for bioenergy (Kretchmer et al, 2012)

� The share varies significantly due to site-specific conditions and different

management practices applied

7

Straw Left on the field

• Increased soil erosion• Decrease of SOC and nutrients• Yield reduction• Increased use of mineral fertilizers• Decreased N2O emissions• Negative impacts on water and biodiversity

Current use(non-bioenergy)

• Animal bedding

• Mushroom production• Mulching• Fodder• Industry

Potential effects

Replacement withalternative materials and

impacts associated to their production and use.

Removal for bioenergy

Displacementto bioenergy

Effect on SOC and nutrients

� RED and FQD method for default GHG emissions does not include SOC emissions

� Largest impact on C and N pools

� Experimental studies - removal has a limited impact on SOC (low removal rates, limited duration of experiments, substantial input of other organic matter – roots, stubble)

� Larger impact on soil microbial biomass than on total SOC -important for maintaining good soil physical properties and soil fertility → early warning

� Modelling studies – predict larger impact of straw removal on SOC

829 March 2015

SOC emissions (CO2/MJEt)� Based on modelling data for Europe (Lugato et al (2014)

AR_RES scenario - 50% removal of AGR in comparison to straw incorporation)

9

� High variability due to site-specific characteristics

Quantitative example: Influence of removal effectsQuantitative example: Influence of removal effectsQuantitative example: Influence of removal effectsQuantitative example: Influence of removal effects

Impacts on global temperature change

a) Continuous production of 1 MJ of fuel each year : 73% mitigation of straw ethanol by the end of the century

b) sustained production of 1 MJ of fuel for 20 years only: 83% mitigation of straw ethanol by the end of the century

• Dynamic emission profiles in time • Use of instantaneous climate emission metric (surface

temperature response), as opposed to cumulative GWP metric

Forest logging residues

1129 March 2015

• High supply-chain GHG savings, but this indicator is not an accurate measure of climate mitigation effects of a policy

• Biogenic-CO2 emissions from biomass not considered

• Impact of other climate forcers is also important

Global temperature change (WMGHG)

1229 March 2015

2014 2025 2050 2075 2100-0.5

0.0

2.0

4.0

6.0 [x 10-15]

2% yr-1

2.7% yr-1

11.5% yr-1

20% yr-1

40% yr-1

Coal Fuel Oil NG Bioenergy (Branches) Bioenergy (2.7%) Bioenergy (20%) Range decay (2% - 40%)

S

urfa

ce T

empe

ratu

re R

espo

nse

(ins

tant

aneo

us)

[K]

Years

(a)[x 10-15]

2014 2025 2050 2075 2100-0.25

0.0

0.5

1.0

1.5

2.0

2% yr -12.7% yr -1

11.5% yr -1

20% yr -1

40% yr-1

Coal Fuel Oil NG Bioenergy (Branches) Bioenergy (2.7%) Bioenergy (20%) Range decay (2% - 40%)

(b)

Sur

face

Tem

pera

ture

Res

pons

e (i

nsta

ntan

eous

) [K

]Years

a) Continuous production of 1 MJ of heat each year

b) Sustained production of 1 MJ of heat for 20 years – then residues left to decompose

1329 March 2015

Impact of other climate forcers

1429 March 2015

Livestock manuresLivestock manuresLivestock manuresLivestock manures

Solid manure

and liquid slurry

Direct field application as

fertilizers

Current uses

Potential effects of bioenergy use

• GHG savings from avoided emissions (raw manure storage)

• Contribution to the domestic energy supply (replacement of other sources of energy)

• (Potential) Effect on SOC

• Increase N fertilizer potential (short-term) may lead to potential decreased use of mineral fertilizers

• Negative impacts on groundwater

• Decrease odours

• Increase veterinary safety

Anaerobic digestion and digestate

application as fertilizer

Bioenergy Use

Livestock manures

• Management of raw manures and slurries is responsible for large

GHG and other pollutants' emissions (mainly: CH4, N2O and

NH3) (baseline)

• Anaerobic digestion and collection of biogas can avoid most of

such emissions (emission credits) without impacting the function

of organic fertilizer (covered by residual digestate).

• However, potential impacts associated with lower organic matter

supply to the soil could reduce these advantages.

• Also, technological options for biogas plants can have a

significant influence on the final results achieved (leakages and

losses of methane). Especially for energy crops (that have no

credits). Best practices should be promoted to avoid these

emissions.

1529 March 2015

Influence of technological choices

1629 March 2015

Source:

JRC EUR 26696 EN

JG5

Snímka 16

JG5 There are other important potential emissions from biogas plants:

1) Flaring and venting2) accidental leakages3) Upgrading slip streams of methaneGIUNTOLI Jacopo (JRC-PETTEN); 17. 3. 2015

1729 March 2015

Co-digestion of multiple substrates (maize silage and wet manure)

Off-gas vented Off-gas combusted

1829 March 2015

(Baselines =

left on soil

except

prunings)

Total GHG Total GHG Total GHG Total GHG

emissions emissions emissions emissions

compared to compared to compared to compared to

fossil fuelsfossil fuelsfossil fuelsfossil fuels

SOCSOCSOCSOCNutrientsNutrientsNutrientsNutrients

PoolPoolPoolPool

Soil health Soil health Soil health Soil health / / / /

fertilityfertilityfertilityfertilityNNNN2222O, O, O, O, CHCHCHCH4444

Pests, Pests, Pests, Pests,

diseases, diseases, diseases, diseases,

odoursodoursodoursodours

BioBioBioBio----

diversitydiversitydiversitydiversityWaterWaterWaterWater

DisplacemeDisplacemeDisplacemeDisplaceme

nt effectsnt effectsnt effectsnt effects

StrawStrawStrawStraw ☺☺☺ ��� ��� ��� ☺☺ ☺☺ �� � ��

Pruning Pruning Pruning Pruning

residuesresiduesresiduesresidues☺☺☺ ��� ��� ��� ☺ ☺☺ �� �� �

ManureManureManureManure ☺☺☺ ��� ☺ ☺☺ ☺☺☺ ☺☺☺ �� ��No alternative

use

Forest Forest Forest Forest

residuesresiduesresiduesresidues

Short term:

���� �� �� � ☺☺ ��� �

No alternative

use Long-term:

☺☺☺

Qualitative assessment

UCO and Tallows

• UCO (used cooking oil) and waste-grade tallows (animal fats)

produce fuels with higher GHG savings compared to 1st

generation biofuels.

• Some waste tallow already used for heat in rendering factories;

if redirected into biodiesel, its most likely replaced by fossil fuels

• UCO collection volumes in EU can improve. Non-EU sourced

materials available but can have higher transport emissions

• Some non-waste tallows are used for cosmetics, animal feeds

etc; if redirected into biodiesel, most likely replaced by palm oil

• Concerns exist re: non-waste material fraudulently sold as

waste biofuel, lowering GHG savings. Feedstock certification

helps

1929 March 2015

ALGAE biofuels: Macroalgae

2029 March 2015

� Over 10,000 species in intertidal zones ("cast seaweeds") and sub-tidal zones (submerged "kelp")

� Range in size: 10 cm - 60 m (aquatic plants)

Ma

cro

alg

ae

Anaerobic digestion

Fermentation

Hydrothermal conversion

Biogas

Bioethanol

Crude oil

Off-shore cultivation

On-shore cultivation

Wild stocks

• Sunlight

• Water(seawater,wastewater)

• Fertilizers

� Cultivation: key questions about yield and composition of biomass, resource supplies, site selection, sustainability issues for aquatic systems

� Wild harvest: impacts on the biodiversity of flora and fauna

ALGAE biofuels: Microalgae

2129 March 2015

� Over 30,000 species in various marine and freshwater habitats � Range in size: 2 - 20 µm (unicellular, lack of roots, stems and leaves)

� Benefits potentials: use of non-food crops lands (low iLUC), higher oil yields (60 m3 ∙ ha-1) than other crops (e.g. soybean (0.45 m3 ∙ ha-1)

� Cultivation: key questions about different designs, high demands of resource supply (CO2, fertilizers, water), influence of water types on biomass yield

Cultivation in open ponds (ORP)

Cultivation in photobioreactor (PBR)

• Sunlight

• Water(freshwater,seawater,wastewater)

• Fertilizers

• CO2 Mic

roa

lga

e

Lipids extraction and

conversion

Fermentation

Anaerobic digestion

Hydrothermal conversion

Biodiesel

Bioethanol

Biogas

Pyrolysis oil, jet fuel

2229 March 2015

ALGAE biofuels: Microalgae biodiesel

� Low estimates of energy returns, biogas (from residual biomass) is a key parameter for electricity/heat production for on-site use and nutrients recovery

� Significant uncertainties on key parameters/technologies, lack of operational data

Biodiesel

Cultivation

Harvesting-dewatering,

drying

Lipids extraction

Transesterification

Glycerol

Algal biomass

Coproduct management

Coproduct managementAnaerobic digestion

Digestate

Coproduct management

Biogas

Combustion

Electricity

Heat

Water

CONCLUSIONS

29/03/2015 23

• Biofuels are one of the few options to reduce GHG emissions in

transport

• Advanced biofuels may offer advantages with respect to first-

generation, but sustainability and market mediated effects

(competition with other sectors, displacement from existing uses, etc.)

have to be considered.

• Net GHG savings in the long-term for all the analysed residues

• Other impacts present medium to high risks, especially biodiversity

and decrease of SOC

• Additional impacts usually worse than fossil (eutrophication, PM etc…)

• Further long-term research needed

IS BIOENERGY FROM IS BIOENERGY FROM IS BIOENERGY FROM IS BIOENERGY FROM RESIDUES AND WASTES RESIDUES AND WASTES RESIDUES AND WASTES RESIDUES AND WASTES REALLY AND REALLY AND REALLY AND REALLY AND

ALWAYS SUSTAINABLE?ALWAYS SUSTAINABLE?ALWAYS SUSTAINABLE?ALWAYS SUSTAINABLE?

2429 March 2015

Precautionary approachPrecautionary approachPrecautionary approachPrecautionary approach

• The word "residue" is not automatically synonym with "sustainable"

• GHG reductions may come at the expenses of other impacts

• Mitigation measures and techniques can often be found and arranged

• But first we need to be aware of the issues

• Choices that cause trade-offs in impacts should be made knowingly and not out

of ignorance.

Straw: Environmental impactsSOC Impact −−−− Removal of C contained in the residues, increasing risks for runoff and soil erosion, accelerating SOC

mineralization under the bare soil surface because of alterations in soil temperature and moisture regimes;Larger impact on soil microbial biomass.

Mitigation Removal rates determined on a site-specific basis;Conservation tillage, adequate crop rotation, cover crops, cropping intensification;Application of alternative soil improvers, use of biochar or by-product of fermentation;Adequate monitoring regime

Nutrients Impact −−−− Larger removal of N; removal of P and K are also significant

Mitigation Replacement with mineral fertilizersApplication of fermentation by-product

Nutrient loss Impact +

−−−−−−−−

Incorporation of straw and mineral fertilisers can cause higher N application due to initial N nitrogen immobilisation, fertilisation is planned not considering fertilisation value of straw;Increased runoff and leaching;Initial immobilization of N by microbial decomposition of straw and slow release offers a possibility to improve N efficiency

Mitigation Management practices that reduce nutrient loss (e.g. adequate rate, timing and method of fertiliser application, use of cover crops, nitrification inhibitors, precision farming, reduced tillage)

Yields Impact −−−− Due to nutrient removal, higher water and temperature stress (highly variable)

Mitigation Replacement of nutrients removed;Straw management practices defined on site-specific characteristics

Pest/Diseases

Impact + Removal with the straw (usually small impact)

Mitigation

Water Impact −−−−−−−−

Additional input of mineral fertilisersIncrease of sediment and nutrient delivery in nearby waters

Mitigation Management practices that reduce soil erosion and nutrient loss;Appropriate drainage system;Riparian buffer strips and infiltration belts

Biodiversity Impact −−−− Species depending on agricultural habitats, e.g. farmland birds; species living in soil due to lower input of fresh organic matter; water ecosystems due to increased inflow of sediments and nutrients

Mitigation Use of cover crops to provide alternative habitat;Implementation of management practices that reduce soil erosion and nutrient loss

25

Straw: Displacement effect

Use Alternative

Soil improver Manure, mineral fertilisers, green manure and cover crops

Animal bedding Woodchips, shavings and sawdust, waste shredded paper, paper crumb, and lime ash, high-yielding grasses, plastic mattresses

Animal fodder supplement Hay, silage, commercial feed, out grazing

Mushroom production (growth substrate) Compost, sawdust, other lingo-cellulosic material

Frost prevention in horticulture Limited commercial alternatives, plastic sheeting is used, but still requires some straw

Strawberries (preventing damage to fruit) Matting or plastic sheeting

Compost industry Wood chip, other plant fibre with low N content

Traditional building materials Alternatives include all common building materials

Energy Other biomass feedstock depending on boiler structure / other biofuel feedstock

2629 March 2015 Kretchmer et al. (2012)

Forest logging residues: impacts and mitigation

27

Impact

category Potential risks / benefits Mitigation measures

Soil organic

carbon

= A reduction of SOC associated with whole-tree harvesting was predicted by various

modelling studies (Wall, 2012). However, meta-analyses of field studies have not

substantiated such results. Only a small percentage of the experimental data

analysed indicated a decrease in SOC when removing logging residues (Johnson

and Curtis, 2001; Nave et al., 2010; Wall, 2012). However, the actual effects on

SOC may become evident in the very long-term.

= Stump removal is responsible for soil disruption at depths reaching 1 m (Moffat et

al., 2011). This could favour soil mixing and mineralisation.

Nutrients

pool1

- More than half of total tree N stock is contained in logging residues for spruce and

pine. Of this amount, about half is contained in needles and it is released faster than

the N in branches. Thus, removing residues may impact mostly the quantity of

available N rather than total N soil stock (Tuomasjukka et al., 2014).However, N

depletion is considered more critical in areas of low atmospheric deposition and in

low-fertility soils (Wall, 2012).

- Experimental results consistently indicate decreases in calcium, potassium,

magnesium and phosphorus when residues are removed (Wall, 2012).

- Increase of the acidity of soil is also recorded (Wall, 2012).

- Therefore, soils with low fertility and smaller nutrient pools are more subject to

suffer from the removal of residues and nutrients (Fritsche et al., 2014).

- Stumps contain a small fraction of macronutrients, but coarse roots are responsible

for significant inputs of nitrogen and potassium to the soil (Moffat et al., 2011).

• Leaving foliage and needles,as well as bark, on the forest floor could largely mitigate the

losses of nutrients and growth losses associated with the removal of logging residues (Egnell ,

2011; Lattimore et al., 2009; Tuomasjukka et al., 2014).

• Mitigation of soil acidification via liming could be considered, but negative effects on tree

growth have been reported when applying lime on forest soils (Saarsalmi et al., 2011).

• Re-application of combustion ashes could also return some macronutrients to the soil, but the

eventual positive effects of ash application on tree growth are still uncertain. Data even

suggests decreased growth when ashes are recirculated on nitrogen-poor soils (IEA, 2014).

• Nitrogen is almost completely lost during combustion, so it is not present in ashes and will

need to be supplied via synthetic or organic fertilisers. Experimental data have shown

increased growth rates in fertilised forests, but guidelines in some countries still advise against

synthetic forest fertilisation (Fritsche et al., 2014; Stupak et al., 2007).

• Avoid extraction on rocky, dry and poor soils (Lamers et al., 2013; Wall, 2012)

Soil health

and

productivity

= Many studies have shown results that are not statistically different when comparing

trees grown on sites where residues are either collected or left on floor.

+ Some studies have shown smaller diameters for trees grown in areas where residues

were regularly removed. This has been linked to the initial soil nutrients capital and

the relative fraction of nitrogen removed with the residues (Holub et al., 2013; IEA,

2014; Thiffault et al., 2011).

• Measures to compensate for nutrients losses may actually have negative consequences on

forest growth (see above). These measures should thus be assessed on a case-by-case basis by

developing site-specific nutrient management regimes (Lamers et al., 2013).

• A combination of ash recirculation and urea supply has shown increased volume production of

almost 45% compared to the control study (Saarsalmi et al., 2012).

• Negative impacts of residues accumulation have also been reported. An abundant bed of

residues may delay the stand establishment by as long as one year (Hakkila, 2004) and

excessive, long-term accumulation of residues on the forest floor could limit productivity