Technologies for small scale Biomass CHP-Plants an actual survey

Transcription

1 Technologies for small scale Biomass CHP-Plants an actual survey Risoe, May, 20th 2003 Dr.-Ing. J. Fischer Institute for Energy Economics and Rational Use of Energy, IER, University of Stuttgart Hessbrühlstr. 49A., D Stuttgart, Germany Tel.: / , Fax: / Internet: Seite 1

2 EU: Primary Energy Consumption 2001 hydropower 4% wind 1% biomass 3% nuclear 13% coal 14% EU 15: Primary Energy Demand (2001) 63,9 EJ oil 42% natural gas 23% Seite 2

3 EU-15 Donnerstag, 24. Juli Biomass: Maximum Contribution Seite 3 Germany Finland France Greece Great Britain Ireland Italy Netherlands Austria Portugal Sweden Spain % Belgium, Lux. Denmark

4 Application of Biomass Source: Heinrich, 2001, (modified Seite 4

5 Technologies for Heat and Power generation Source: BIZ 2002, BMU 2002, IE 2002 Seite 5

6 Parameters of important Technologies Seite 6

7 Processes f. Electricity generation Steamprocess Dust engine/-turbine ORC--process Hot Gasturbine Gasification - engine Gasification - gasturbine Gasification - fuel cell Pyrolysis - gasturbine Vegetable oil- engine RME-engine Bioethanol - engine Methanol - engine* Methanol - fuel cell* Theoretical investigations Laboratory, testing,of components Pilotplant Demonstration - plant Market Methan - fuel cell * Co- Combustion Biogas Biogas - fuel cell * = if biomass is used Seite 7

8 Internal Combustion Engine, Biogas Seite 8

9 Advantages Steam Turbine Disadvantages! Mature, proven technology! Small steam turbines < 1 MW el offer only limited efficiencies! Broad power range available! For large installations: high efficiencies can be obtained by high steam temperatures and pressures! Separation between combustion and power generation enables the use of ash containing fuels! Low efficiency at partial load! High specific investment costs for small turbines! For biomass application: limited super heater temperature because of risk of high temperature corrosion Seite 9

10 Steam Engine Advantages! Suitable for lower power ranges! Saturated steam can be used! Very good performance at partial load! Steam extraction at various pressures possible due to modularity! Oil free construction avoids steam contamination Disadvantages! Maximum power output is limited to about 1.2 MW el! High maintenance costs! Electrical efficiency is limited due to low steam pressures (< 25 bar)! Heavy vibration and noise production Seite 10

11 ORC - Process Advantages Disadvantages! Robust technology! Relatively high specific investment costs! Very good controllability and! Long term experiences using high degree of automation biomass still missing! Low maintenance required! Organic thermal oil is inflammable and toxic! Very good performance at! Due to low pressures ( partial load bar) only limited electrical efficiency! Low temperature waste heat can be used Seite 11

12 Stirling - Engine Advantages! Engine operates independently of type of heat source! Low quality demand with respect to fuel! Low maintenance demand because of few moving parts and external combustion! Formation of emissions like CO and CH can be avoided due to external combustion of (bio-) gas Disadvantages! If solid biomass is used, relatively low electrical efficiencies are achieved! no reliable solution for sealing problems! High specific investment costs! Heat exchanger is exposed to extreme wear because of high temperature strain! Risk of high temperature corrosion in ash containing flue gases Seite 12

13 Gasification Seite 13

14 Fuel Cell Seite 14

15 Microturbine Seite 15

16 Costs of Biomass CHP-Plants Steam turbine/engine ORC Stirling Gasification, fuel cell Gasification, turbine Gasification, engine Rapeseed CHP Biogas CHP /kw el Source: Fichtner, Kaltschmitt, IEA, Heinz, BIZ Seite 16

17 Conclusions! Biomass may contribute to a large extent to a sustainable Energy Future in Europe! Biomass is due to its properties best suited for small scale, decentralised CHP-Plants! Limited interest in bioenergy within the last decades leads to a lack of efficient technologies for this purpose! Increased research work, a closer cooperation among research institutes and industry and a better information transfer are essential to activate the enormous potential of bioenergy Seite 17

18 THANK YOU FOR YOUR KIND ATTENTION Seite 18