86025 energy systems analysisarnulf grubler 86025_3 fundamental of energy systems ii

86025 Energy Systems Analysis Arnulf Grubler

86025_3

Fundamental of Energy Systems II


Energy Systems Constraints: Integration Demand - Supply

Physical:• Matching form value • Matching spatial scales• Matching temporal scales

Societal - Availability of:• Capital• Information • Incentives• Policy attention


Energy Constraints

• Matching “form value”: need (and limits) of conversion (e.g. radiant→mechanical energy)

• Spatial mismatch supply-demand: World trade in fuels >1000 Billion $ (2003 data);

• Temporal mismatch supply-demand (load curves): Need for storage & interconnection (capital intensive)

• Magnitude mismatch supply-demand: Power densities, e.g. renewables vs. urban energy use


Energy Constraints I: Space• Fossil fuels: Deposits determined by

nature• Extremely uneven distribution of

reserves: Oil<Coal<Gas• Transport costly:

Electricity<LNG<Gas<Coal<Oil• Inventory (storage) minimization

increases vulnerability (only 90 days oil use in strategic reserves)

• Renewables: Land availability as major spatial constraint

86025 Energy Systems Analysis Arnulf Grublerhttp://www.bp.com/centres/energy2002/gas/trademovement.asp#


US – Gas Pipeline Transport Flows

World Oil Trade in 2004(net trade of crude and oil products)

Million Tons Billion US$

USA -590.8 -165.3

Europe -524.0 -147.1

Japan -254.0 -42.0

China -149.7 -40.1

Other importers -862.2 -242.1

Middle East 959.7 269.4

Africa 319.7 89.8

Ex-USSR 314.3 88.2

Latin America 197.7 55.5

Other exporters 589.3 165.4

World Trade 2380.7 668.4

Source: BP Statistical Review of World energy 2005

How Much Do Fuels Costs the World?

• The power of “back-of-the envelope” calculations

• World crude oil trade: 2.6 109 tons*

• 1000 109 $*

• World oil use: 3.8 Gtoe

• World energy use: 10 Gtoe

• World GDP: ~45 1012$*

• Rough (upper) estimate is: ?* 2005 data from BP Stat. Review 2006 and IMF 2006

using (high) oil prices: <10%;using avg. energy costs and long-term average oil prices: 3-5% of GWP


Energy Constraints II: TimeWhy Electricity Load Curves Matter

• Electricity can’t be stored at reasonable costs; storage of other energy forms also costly

→ Therefore: Electricity must be generated whenever demand arises

→ Therefore: Need enough installed generation capacity to meet peak demand (plus reserve margin), even though system peaks very rarely (few hrs/yr)

• Result: Some plants run only a few hours per year (economics! efficiency!)

• Peak load versus average load: Times 3

• Reserve margin: 10-30% of peak load

• Fractality: Daily, weekly, monthly, yearly load curves


Cum. Annual Electricity Load Curveakin “load duration curve” (US)

MEDIUM LOAD PLANTS

Pumped hydro, gas turbines

Gas combined cycle, coal

Hydropower (rivers), nuclear, coalPow

er d

eman

d


Heat Load Curve of an Austrian Hotel with Electricity Cogeneration(“stacked” boilers due to inefficiency of low capacity utilization;

Never design a heating system based on peak load!)

hours per year

x

kWth

electric boiler 50 kWth


Daily Load Curves: Tokyo

Source: Mogouro et al., 2002


Linking Space and

Time in Tokyo: Power

Density of Demand

Source: Mouguro et al., 2002

Tokyo – Electricity Demand vs. Solar Energy Supply

1

10

100

1000

10000

100000

0 1000 2000 3000

km2

kWh

Solar radiation converted to electricity

Solar radiation

Electricity demand

Source: TEPCO & NIES, 2002


Spatial Power Densities of Energy Production and Consumption

Photovoltaics

Houses

Photovoltaics

Thermalpowerplants

Oil fieldsCoal fields

High-rises

Supermarkets

Flat plate collectorsIndustry

TidalPhotovoltaics

Wind

Hydro

Photosynthesis

Cities

Centralsolar

towers

Steel mills,refineries

Photosynthesis

Source: Adapted from Smil 1991:243


Energy Density Example I:

Hambach Lignite Mine Germany


INDEN HAMBACH

BERGHEIM

FORTUNAGARSDORF

NuclearResearchCentre

Large ScaleOpencast Brown Coal MiningGermanyNew & West Havenfor scale comparison


An IE Perspective on Hambach

• The “1 TW hole”• 3000 billion tons lignite reserves

= 1 BTCE = 1 TWyr = 30 EJ• 8500 ha mined between 1980-2040

(all reclaimed)• Largest man-made machines in the world

(240,000 m3/day bucket wheel excavators)

2004: 40 million tons lignite500 million tons overburden removed600 million tons water pumped

1 ton of lignite (~2 bbls of oil) = 30 tons of material handling

Energy/Carbon Densities: Example II:C sequestered by fuel substitution vs. forest

sinks and sources

Substitution

(bio for fossils)

Source

(deforestation)

Sinks

(afforestation)

Source: Science 317(17 August 20907):902


Power Densities II

• Spatial mismatch between demand and supply requires imports (domestic+international)

• >80% of world energy use in urban high demand density areas

• Power density mismatch biggest for renewables (except large hydro)

• Hence: Renewables best suited for niche markets: low population/energy density areas (rural),

Europe: Power Density of Demand (W/m2): Grey areas indicate where biomass or wind can satisfy local

energy demand (< 0.5 W/m2)

England:

Energy demand footprint

larger than country area

Orders of Magnitude: 1 W/m2 upper energy yield of biomass/wind ~10 kWh/m2 resulting annual energy yield ~30 MJ/m2

~300 GJ/ha~10,000 liters/ha liquid fuel with 100%

conversion efficiency ~1,000 gal/acre (for the non-metric inclined) ~10 toe/ha tons oil equivalent yield

(max. yield, no losses!) ~3 toe/ha realistic yield incl. conversion losses

US transport energy use: ~600 Mtoe =200 million ha = ~100% of all cropland

World energy use (PE): ~10 Gtoe =3000 million ha = 200% of cropland area,or 75% of forests

The Economics of Land-use Conflicts:Bioenergy and Agricultural Crop Yields

(typical, rounded values)

Crop Yield per ha Producer Price Yield $/haWheat Brazil 2 t 110 $/ton 220

Soybeans Brazil 2.5 t 150 $/ton 380

Rapeseed Germany 3.5 t 170 $/ton 600

Sugarcane Brazil 68 t 10 $/ton 680

Wheat France 7 t 100 $/ton 700

Cotton USA 2 t 420 $/ton 840

Rice China 6 t 140 $/ton 840

Tobacco India 1.5 t 560 $/ton 840

Tobacco USA 2.4 4200 $/ton 10,000

Low yield/price biomass 3 t (10 GJ/t) 3 $/GJ 90

Med. yield/price biomass 10 t (14 GJ/t) 4 $/GJ 560

High yield/price biomass 18 t (18 GJ/t) 6 $/GJ 2,000

Rapeseed EU biodiesel 1300 l 0.6 $/litre 850

Sugarcane Ethanol Brazil 6000 l 0.2 $/litre 1,200

Palmoil Indonesia 6000 l 400-600 $/Klitre 2,400-3,600


Choice of Energy Systems and Technologies

• Need to satisfy first all energy systems constraints

• Need to satisfy demand for energy services rather than fuels

• Economics not all (invisible costs, convenience, social visibility, etc.)

• Choices available inverse of scale (family home, plant, vs. planet)

• Analysis needs large system boundaries


Energy Chains and Analysis

For MEMs: LCA


Energy Chain Analysis:Example of IIASA CO2DB

• Broad coverage (end-use to extraction, ~2000 technologies)

• Comprehensiveness (technological, economic, emissions characteristics)

• Multiple entries (uncertainties, regional differences)

• No single „best guess“ (reflecting dynamicsin time, process variation, heterogeneity)

• Analysis (queries, energy chain analysis)


The Cost of Lighting$/k-lumen-yrThe Costs of Lighting($/k-lumen-yr)

3 supply systems:hcppl hard coal power plantngcc gas combined cyclengccr gas CC w. CO2recovery2 end-use tech’sic incadescent light bulbscl compact flourescent lb

Fuels

Conversion

End use

T&D

Cross-cutting

12

34 55

6


CO2 Emissions of Lighting(kg C/k-lumen-yr)

2

43

6 15

Cheapest and 2nd cheapestchains


Energy Chain & LCA Analysis

+ Easy comparison at investment margin+ Analytical simplicity+ Data sharing+ Good for project-specific analysis

(GEF „additionality)+ Imports can be considered

- Representativeness of examples under proliferation of combinations (xn!)

- Largely static analysis (what‘s the investment „margin“?)

- Reconciliation of multiple criteria(costs, emissions)

- System aspects: Diffusion potentials and constraints (capital, vintage structure, environment, relative shares of various chains)


I-O: Input-Output Analysis

• Basically a matrix of monetary flows across sectors of an economy

• Info: one unit of output of sector i needs how much ($) inputs from other sectors (j..n)

• Based on detailed (but lagged) nationally reconciled sectorial statistics

• Complemented by physical flows(e.g. energy, CO2 emissions)


US- Energy per $ Value Added (TJ per Million $, energy embodiment, 1992 I-O data)

Source: Carnegie Mellon Univ. www.eiolca.net

Product On-site Energy Transport Other Totalsupply sectors

fertilizer 130.4 7.6 3.2 6.6 147.8passenger cars 1.2 3.7 1.4 6.4 12.6hotels 2.9 5.4 0.5 1.9 10.7semiconductors 0.9 3.3 0.5 2.7 7.4real estate agents 0.8 2.4 0.3 1.2 4.7computer&data services 0.2 1.2 0.3 1.1 3.0

Direct energy Indirect energy

Note product and value orientation:Energy embodied in car vs. total energy use over lifetime of carEnergy $ per VA $: industry vs. services (energy price differences)


I-O Tables for Energy and Environmental Analysis

+ Comprehensive national accounting

+ Widely available (mostly in OECD however)+ Basically only data source for “indirect” energy and

“rucksack” environmental impacts (=things happening outside the sector of consideration but linked to it)

+ Possibility to combine with physical I-O info

- Static and often delayed (-5 to -10 yrs) snapshot- Average sectorial picture (difference to marginal

investments)- Little end-use (consumption) detail- Constrained by national border systems boundary


B-U Engineering Modeling

• Representation of conversion technologies linking I-O

• Simulation or optimization (LP) based

• Dynamic (back-and forecasting)

• LPs: Clear, simple decision rule: (discounted) cost minimization under constraints

• Trade explicitly considered

• Data rich


Energy Flows in MESSAGE Model

1990 -- 2020


B-U Engineering Models

+ technology detail

+ multi-criteria analysis+ environmental constraints explicitly considered+ dynamic, systems view

- Extremely data intensive- Decision rule simplistic

(global cost minimization)- Consumer choices poorly modeled

(“rational choice” assumed)- Linkage to other sectors: only captured if coupled

with macro-economic models (complex)

86025 energy systems analysisarnulf grubler 86025_3 fundamental of energy systems ii

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