Renewable Energy: Overview

Wim C. Turkenburg

Copernicus Institute for Sustainable Development and Innovation

Utrecht UniversityThe Netherlands

Unicamp, Campinas, Brazil19 February 2002

WORLD ENERGY ASSESSENT

Renewable Energy & WEA

• Chapter 5:

Energy Resources

(Hans-Holger Rogner)

• Chapter 7:

Renewable Energy Technologies

(Wim C. Turkenburg)

Lead authors chapter 7: - Jos Beurskens - André Faaij - Peter Fraenkel - Ingvar Fridleifsson - Erik Lysen - Davis Mills - Jose Roberto Moreira - Lars Nilsson - Anton Schaap - Wim Sinke

Advantages Renewables

• Improving access to energy sources

• Diversifying energy carriers

• Balancing the use of fossil fuels

• Reducing dependence on imported fuels

• Reducing pollution from conventional energy systems

• Suited to small and large scale applications

Disadvantages Renewables

• Technologies often capital intense

• Energy costs often not (yet) competitive

• Diffuse energy source: spatial requirements

• Environmental concerns (hydro, wind, biomass)

• Intermittent character (wind, solar)

Present contribution Renewables

World primary energy consumption in 1998______________________________________________________________________________________________

Fossil fuels: 320 EJ (80%) - oil 142 EJ - natural gas 85 EJ - coal 93 EJ______________________________________________________________________________________________

Renewables: 56 EJ (14%) - large hydro 9 EJ - traditional biomass 38 EJ - ‘new’ renewables 9 EJ______________________________________________________________________________________________

Nuclear: 26 EJ (6%)______________________________________________________________________________________________

Total: 402 EJ (100%)

Technical Potential Renewables

Supply in 1998 Technical potential

Biomass 45 ± 10 EJ 200-500 EJ/y

Wind 0.07 EJ 70-180 EJ/y

Solar 0.06 EJ 1,500-50,000 EJ/y

Hydro 9.3 EJ 50 EJ/y

Geothermal 1.8 EJ 5,000 EJ/y

Marine - n.e.

Biomass energy conversion

Sources:

- plantations

- forests residues

- agricultural residues

- municipal waste

- animal manure

- etcetera

Biomass energy conversion

• Production of heat:improved stoves, advanced domestic heating systems, CHP.

• Production of electricity:(co-)combustion, CHP, gasification (BIG-CC, engines), digestion (gas engines).

• Production of fuels:ethanol, biogas, bio-oil, bio-crude, esters from oilseeds, methanol, hydrogen, hydrocarbons. Produced by: extraction, fermentation, digestion, pyrolysis, hydrolysis, gasification and synthesis.

Status biomass energy

• Cost biomass from plantation already favourable in some developing countries (1.5-2 $/GJ).

• Electricity production costs of 0.05-0.15 $/kWh.• New technology (BIG-CC) needed to reduce

electricity production costs to 0.04 $/kWh.• Advanced technologies to produce bio-fuels

(methanol, hydrogen, ethanol) at competitive cost (6-10 $/GJ).

Biomass energy development strategies

• More experience with, and improvement of, the production of energy crops.

• Creating markets for biomass.• Development and demonstration of key

conversion technologies.• Poly-generation of biomass products and energy

carriers from biomass.• Policy measures like internalizing external costs

and benefits.

Modern wind energy

Modern wind farms some key figures

• On land wind farms: capacity varying from 1 MW to 100 MW (Spain even 1000 MW)

• Typical ex-factory price : US$ 350 to 400 per m² rotor swept area

• Installed power varying from 400 W/m² (low wind speed area) to 550 W/m² (high wind speed area)

• Present most applied turbines: 0.6 MW to 1.5 MW (or approx. 43 m Ø to 60 m Ø).

Market development

Market developmentsome key figures

• Total installed power 23,300 MW (end 2001, world).

• 82% of power in only 5 countries (D, DK, E, USA, India)

• Growth during last 5 years: > 30 %/year.

• ‘Progress’ factor: 80 %.

• Energy pay back time: 0.25 - 0.5 years.

• Technical life time: 20 years.

Future development wind

• Wind turbines become larger.• Wind turbines will have fewer components.• Special offshore designs.• 10 percent grid penetration maybe around 2020.• Installed capacity in 2030 could be 1,000 – 2,000

GW.• Potential development energy production costs:

0.05 –> 0.03 $/kWh (+ 0.01 $/kWh for storage).

Solar PV stand-alone systems• consumer products• telecom• leisure• water pumping• lighting & signalling• rural electrification• etc.

PV-pumped cattle drinking trough (NL)

Solar Home System

(Bolivia)

Grid-connected PV systems

• building- & infrastructure-integrated PV– roofs– facades– sound barriers– etc.

• ground-based power plants

“City of the Sun” 50,000 m2 PV (NL)

PV sound barrier (NL)“PV gold” (Japan)

PV market growthshipments per year (MW)

0255075

100125150175200225250275300

ROW 3 4 4.7 5 4.6 4.4 5.6 6.35 9.75 9.4 18.7 20.5 23.42

Europe 6.7 7.9 10.2 13.4 16.4 16.55 21.7 20.1 18.8 30.4 33.5 40 60.66

Japan 12.8 14.2 16.8 19.9 18.8 16.7 16.5 16.4 21.2 35 49 80 128.6

USA 11.1 14.1 14.8 17.1 18.1 22.44 25.64 34.75 38.85 51 53.7 60.8 74.97

Total 33.6 40.2 46.5 55.4 57.9 60.09 69.44 77.6 88.6 125.8 154.9 201.3 287.65

1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

Status Solar PV

• Conversion efficiencies of PV modules ranging from 6-9% (a-Si) to 13-15% (x-Si).

• Many PV technologies under development.

• Increase PV shipments (50 MW in 1991; 150 MW in 1998; 280 MW in 2000).

• Continuous reduction investment costs (learning rate ~20%).

• > 500.000 Solar Home Systems installed in last 10 years.

Potential development Solar PV

• Investment costs grid-connected PV-systems may come down from 5-10 $/W –> 1 $/W.

• Energy payback time may come down from 3-9 years –> 1-2 years (or less).

• Electricity production costs may come down from 0.3-2.5 $/kWh –> 0.05-0.25 $/kWh.

• PV can play a major role in rural electrification.

Future of PV: some conclusions

• PV technically sufficiently mature for large-scale use.

• large room for improvement in cost (x 1/5) and performance (x 2).

• major contribution (EJ, CO2) from PV requires long-term approach, but:

• great commercial, economic, and development opportunities.

Solar Thermal Electricity

• Production of high temperature heat, using concentrating systems, to generate electricity

• Applicable in sunnier regions• All technologies rely on four basic elements:

- collector / concentrator

- receiver

- transport / storage

- power conversion

Solar Thermal Electricity

Single Axis Tracking: Through system

- commercial available since 1980’s

- current energy costs 0.12-0.18 $/kWh

- potential energy costs 0.06 $/kWh

Solar Thermal Electricity

Two Axis Tracking: Solar Tower

- started 1980’s, several built

- Illustration: Solar One 10 MW plant (Barstow, California, 1982-1988)

- Solar Two recently demonstrated molten salt heat storage, delivering power to the grid on a regular basis

Solar Thermal Electricity

Two Axis Tracking: dish / heat engine power plant

- several prototypes operated successfully in last 10 years.

- size prototypes: ~ 400 m2; 10 kWe.

- 2-3 MWe dish plant under development, attached to existing power plant.

STE: some conclusions

• Installed STE capacity about 400 MWe (1 TWh/y) may grow to 2000 MWe in 2010.

• Solar fields can be integrated into fossil fuel power plants at relatively low cost.

• STE conversion efficiency may increase from 13-16% in near term to 16-20% in long term.

• Electricity production costs may come down from 0.12-0.18 $/kWh today to 0.04-0.10 $/kWh in long term.

Low Temperature Solar Energy

• World’s commercial low-temperature heat consumption: 50 EJ/y for space heating and 10 EJ/y for hot water production.

• Low and medium temperature process heat consumption (up to 200 °C): 40 EJ/y.

• Demand can be met partially with solar energy.

• Mismatch between demand and supply requires heat storage.

Low Temperature Solar Energy

Solar Domestic Hot Water system (SDHW)

- Collector area per system 2-6 m2.

- Energy cost 0.03-0.25 $/kWh.

- Solar fraction 50-100%.

- Collector area installed is about 30,000,000 m2, equivalent to 18,000 MW, generating 50 PJ heat per year.

Low Temperature Solar Energy

Large water heating system

- Around one-tenth of total installed area.

- Wide spread use in swimming pools, hotels, hospitals, …

- Cost per kWh somewhat less than for SDHW systems

Low Temp. Solar Energy Technologies

Other options:• Solar space heating (solar combi-systems).• District heating (central collector area).• Heat Pumps (tens of millions installed).• Solar cooling (poor economics today).• Solar cooking (over 450,000 box-cookers in India).• Solar crop drying (over 100,000 m2 installed).• Passive solar energy use (new building design).

Hydro-electricity

Salto Caxias hydro plant. More than 30% of total investment budget allocated to 26 socio-environmental projects

Electricity from hydropower

GERAÇÃO DE ELETRICIDADE - MUNDO

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PRIMARY SOURCES OF ENERGY FOR WORLD ELECTRICITY GENERATION

Oil based

Large-scale systems:

- 640 GW installed

- 2,510 TWh/year

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Small-scale systems:

- 23 GW installed

- 90 TWh/year

Figures 1997

Natural Gas

NuclearHydroCoal

Hydropower: some conclusions

• Production may increase to 6000 TWh in 2050.• Technologies available to reduce social and

ecological impacts.• Hydropower plants are capital intensive.• Large scale systems: mature technology, unlikely

to advance.• Electricity production costs 0.02-0.10 $/kWh.• Additional advantages: operating reserve, spinning

reserve, voltage control, cold start capability.

Geothermal Energy

• Used for bathing and washing for thousands of years.

• Used commercially for some 70 years

• High temperature fields in more than 80 countries.

• Low temperature resources found in most countries.

Geothermal electricity production

Some conclusions:

• 45 TWh produced in 1998

• Electricity production cost: ~ 0.04 $/kWh

• Efficiency power plant: 5-20 %

• Accessible potential: 12,000 TWh/year

• Annual growth installed capacity: ~ 4 %

Installed capacity in 1998: 8,240 MW

USA: 2,850 MW Philippines: 1,848 MW Italy: 769 MW Mexico: 743 MW Indonesia: 590 MW Japan: 530 MW New Zealand: 345 MW Iceland: 140 MW

Direct use of geothermal heat:some conclusions

• Utilization in 1998: 40 TWh

• Production cost: 0.005-0.05 $/kWh

• Conversion efficiency: 50-70 %

• Accessible resource base: 600.000 EJ

• Annual growth installed capacity: ~ 6%

• New challenge: geothermal heat pumps

Marine energy technologies

• Tidal barrage energy

• Wave energy

• Tidal / marine currents

• Ocean thermal energy conversion (OTEC)

• Other options

Potential contribution renewables

Scenario C1

Scenario C2

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Coal

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Potential contribution renewables

Shell scenario

Potential contribution renewables

Potential contribution in second half of the 21th century:

20 - 50 % of total energy consumption.

Transition to renewables-based energy systems relies on:

- Successful development of renewable energy technologies that become increasingly competitive.

- Removal of barriers to the deployment of renewables.

- New policy instruments to speed-up the diffusion.

- Political will to internalise environmental (external) costs that permanently increase fossil fuel prices.

Policy options: cost-buy-down and dissemination

• Renewable Portfolio Standards (RPS)• Concessions• Green electricity market• Carbon dioxide tax• Subsidies with “sunset” clauses • Retail financing• Clean Development Mechanism

WORLD ENERGY ASSESSENT MAIN FINDINGS