lntegrated Environmental Technology Series
Sewage Treatment Plants: Economic Evaluation of Innovative Technologies for Energy Efficiency
Edited by
Katerina Stamatelatou and -;:>
Konstantinqs, P: Tsagarakis
•
Contents
About the Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Part 1 Innovative technologies and economics in sewage treatment plants - an overview . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 1 Reducing the energy demands of wastewater treatment through energy recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 lntroduction .......................................... 3
1.1.1 Wastewater management ......................... 3 1.1.2 Energy demands for wastewater treatment . . . . . . . . . . . . 4
1.2 Energy Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.1 Use of efficient mechanical parts and sensors ... . ..... 7 1.2.2 Anaerobic digestion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.2.3 Fermentation ................................... 9 1.2.4 Microbial fuel cells .............................. 10 1.2.5 Energy recovery from sewage sludge ............... 10
1.3 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.4 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
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Chapter 2 The principles of economic eva/uation and cost-benefit analysis implemented in sewage treatment plants .. . ... . 15 Maria Molinos-Senante, Nick Hanley, Francesc Hernandez-Sancho and Ram6n Sala-Garrido 2.1 lntroduction ......................................... 15 2.2 Cost Benefit Analysis Methodology . . . . . . . . . . . . . . . . . . . . . . . 16
2.2.1 Cost benefit analysis basis . . . . . . . . . . . . . . . . . . . . . . . 16 2.2.2 Interna! benefit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2.3 External benefit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.3 Conclusions 2 .4 References
Chapter 3 lntroduction to energy management in wastewater
28 28
treatment plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Catarina Silva, Helena Alegre and Maria Joäo Rosa 3.1 Energy management of wastewater treatment plants
put into context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.2 Energy management systems: highlights
of the ISO 50001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 3.3 Energy management and infrastructure asset management ... 40 3.4 A Framework of Energy Performance lndicators and Indices
for WWTPs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3.4.1 Background . ... . ... .. .................... . .... 42 3.4.2 Energy performance indicators . . . . . . . . . . . . . . . . . . . . 43 3.4.3 Energy performance indices . . . . . . . . . . . . . . . . . . . . . . 49 3.4.4 Methodology for PAS application . . . . . . . . . . . . . . . . . . 51
3.5 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Chapter 4 Innovative energy efficient aerobic bioreactors for sewage treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Eoin Syron 4.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 4.2 Aeration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.2.1 Innovative process design and improvement . . . . . . . . . 58 4.3 lncreasing Oxygen Transfer from a Bubble . . . . . . . . . . . . . . . . . 59
4.3.1 Fine bubble diffusers and oxygen transferring technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
4.3.2 lncreasing contact time .......................... 61
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4.4 Bubbleless Aeration-Membrane Aerated Biofilm Reactor . . . . . 61 4.4.1 Submerged membrane aerated biofilm reactors ....... 63 4.4.2 Passively membrane aerated biofilm reactors . . . . . . . . 65
4.5 Low Energy Ammonia Removal . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.5.1 Ammonia removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.5.2 Shortcut nitrification ....... . .. . ................. 67 4.5.3 Anammox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
4.6 Other Aerobic Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 4.6.1 Aerobic granules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
4.7 Conclusions .. .. . ... ................. .. ............. . 68 4.8 References ....... ..... .. . .......................... 68
Chapter 5 Integration of energy efficient processes in carbon and nutrient removal from sewage . . . . . . . . . . . . . . . . . . . . 71 Simos Malamis, Evina Katsou and Francesco Fatone 5.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 5.2 Regulatory Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 5.3 Energy Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 5.4 Conventional Biological Nutrient Removal Processes ........ 74
5.4.1 Description of alternative conventional BNR processes and configurations . . ................... 74
5.4.2 BNR processes implemented in Europe and Northern America ............................... . ...... 80
5.4.3 Energy requirements and cost of conventional BNR processes ......... .. .................. .. . 81
5.5 Innovative Bioprocesses in the Mainstream and Sidestream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
5.6 Nitrous Oxide Emissions in BNR . . . . . . . . . . . . . . . . . . . . . . . . . 89 5.7 Conclusion .......... .. .... . . . ............. . ......... 90 5.8 Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 5.9 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Chapter 6 The aerobic granulation as an alternative to conventional activated sludge process . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Anuska Mosquera-Corral, Angeles Val de/ Rio, Helena Moralejo-Garate, Alberto Sanchez, Ram6n Mendez and Jose Luis Campos 6.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 6.2 Basics of Aerobic Granulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
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6.2.1 Conditions for aerobic granular biomass formation . . . . . 97 6.2.2 Sequencing batch reactors ....................... 99 6.2.3 Factors affecting aerobic granule characteristics
and stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 6.2.4 Biological processes inside the aerobic granules ..... 103
6.3 Comparison with Activated Sludge Systems ............... 105 6.4 Full Scale Applications of the Aerobic Granular
Technologies ....................................... 108 6.5 Acknowledgements .................................. 110 6.6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Chapter 7 Anaerobic digestion of sewage wastewater and s/udge ...... . .... . .......................... . Katerina Stamatelatou 7.1 lntroduction ....................................... . 7.2 The Process ...................................... . 7.3 The Technology .................................... . 7.4 Anaerobic Digestion of Sewage Sludge ................. .
7.4.1 Sonication .................................. . 7.4.2 Microwave .................................. . 7.4.3 Thermal hydrolysis ........................... . 7.4.4 Autohydrolyis - Enzymatic hydrolysis ............. . 7.4.5 Other methods .............................. . 7.4.6 Economic analysis of the pretreatment methods .... .
7.5 Anaerobic Digestion of Sewage ....................... . 7.5.1 Pretreatment of sewage via anaerobic digestion .... . 7.5.2 Treatment of preconcentrated sewage via anaerobic
digestion ................................... . 7.6 Conclusions ....................................... . 7.7 References
Chapter 8
115
115 116 118 119 122 123 123 123 123 124 129 130
132 133 134
Resource recovery from sewage s/udge . . . . . . . . . . . . . . 139 M. G. Healy, R. Clarke, D. Peyton, E. Cummins, E. L. Moynihan, A. Martins, P. Beraud and 0 . Fenton
8.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 8.2 Defining Trends for Municipal Sludge Treatment . . . . . . . . . . . . 140
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8.3 Sewage Sludge as a Resource . . . . . . . . . . . . . . . . . . . . . . . . . 141 8.3.1 Nutrient recovery from sewage sludge . . . . . . . . . . . . . 141 8.3.2 Volatile fatty acids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 8.3.3 Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 8.3.4 Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
8.4 Legislation Covering Disposal of Biodegradable Waste on Land . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
8.5 Existing and Emerging lssues Concerning the Re-Use of Biodegradable Waste on Land . . . . . . . . . . . . . . . . . . . . . . . . . 148 8.5.1 Societal issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 8.5.2 Nutrient and metal lasses . . . . . . . . . . . . . . . . . . . . . . . 148 8.5.3 Pathogens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 8.5.4 Pharmaceuticals .............................. 150
8.6 Quantification of Costs and Benefits from Re-Use of Sewage Sludge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 8.6.1 Impact of nutrient recovery, energy/product
generation on energy and cost savings in a sewage treatment plant . . ..................... 154
8.7 Acknowledgements .................................. 155 8.8 References ........................................ 155
Chapter 9 Odour abatement technologies in WWTPs: energy and economic efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 Jose M. Estrada, Raquel Lebrero, Guillermo Quijano, N. J. R. Bart Kraakman and Rauf Mufioz 9.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 9.2 Odour Abatement Technologies ........................ 165
9.2.1 Design and economical parameters . . . . . . . . . . . . . . . 168 9.3 Comparative Parametric Efficiency
Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 9.3.1 Energy consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 9.3.2 Energy efficiency parameter . . . . . . . . . . . . . . . . . . . . . 174 9.3.3 Sustainability efficiency parameter . . . . . . . . . . . . . . . . 177 9.3.4 Robustness efficiency parameter . . . . . . . . . . . . . . . . . 179 9.3.5 lnfluence of the H2S concentration . . . . . . . . . . . . . . . . 181 9.3.6 Exploring alternatives to increase technology
efficiency: LID ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 9.4 Conclusions ........................................ 184 9.5 References ........................................ 185
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Chapter 10 Instrumentation, monitoring and real-time control strategies for efficient sewage treatment plant operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189 Sergio Beitran, Ion lrizar and Eduardo Ayesa 10.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189 10.2 Instrumentation for Monitoring and Control Purposes ........ 190 10.3 Control of Aeration Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 10.4 Control of Chemical Addition ........................... 197 10.5 Control of the Interna!, External and Sludge Wastage
Flow-Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 10.5.1 Control ofthe nitrates internal flow-rate and the
carbon external addition . . . . . . . . . . . . . . . . . . . . . . . . 198 10.5.2 Control of the external flow-rate or sludge
recirculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 10.5.3 Control of the sludge wastage flow-rate ............ 200
10.6 Control of Anaerobic Processes . . . . . . . . . . . . . . . . . . . . . . . . 201 10.6.1 Technological barriers .......................... 202 10.6.2 Applications of control in anaerobic digestion . . . . . . . . 202
10.7 Plant-Wide Control . ................................. 205 10.8 Conclusions ........................................ 206 10.9 References ........................................ 207
Chapter 11 Microbial Fuel Cel/s for wastewater treatment . . . . . . . . . 213 V. B. Oliveira, L. R. C. Marcon, J. Vilas Boas, L. A. Daniel and A. M. F. R. Pinto
11.1 lntroduction ........................................ 213 11.2 Operating Principle of a MFC .......................... 214 11.3 Fundamentalsand Challenges ............... . ......... 215 11.4 Scale Up .......................................... 217 11.5 Operational Conditions .... . .......................... 220
11.5.1 EffectofpH .................................. 220 11.5.2 Effect of temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 11.5.3 Organic load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 11.5.4 Feed rate and shear stress . . . . . . . . . . . . . . . . . . . . . . 225
11.6 Mod~lling Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 11.7 Economic Evaluation ................................. 228 11.8 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 11.9 Acknowledgements .................................. 231 11.10 References ........................................ 231
Contents xi
Part II Innovative technologies and economics in sewage treatment p/ants - case studies . . . . . . . . . . . . . . . . . . . . . 237
Chapter 12 Management optimisation and technologies application: a right approach to ba/ance energy saving needs and process goa/s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 P. Ragazzo, L. Falletti, N. Chiucchini and G. Serra 12.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 12.2 Energy Saving with Maintenance and Control Operations .... 240
12.2.1 Initial situation of plants . . . . . . . . . . . . . . . . . . . . . . . . . 240 12.2.2 Interventions on pumps and piping system .......... 242 12.2.3 Interventions on mixers and engines ....... . ...... 243 12.2.4 Interventions on air compression and distribution . . . . . 244 12.2.5 When energy and process efficiency do not agree .... 246
12.3 Energy Saving Choosing the Right Technology ...... . . . ... 247 12.4 Conclusions . . . . .... .. .. ... ......................... 248 12.5 References ............... . ........................ 249
Chapter 13 Energy factory: the Dutch approach on wastewater as a source of raw materials and energy . . . . . . . . . . . . . . 251 Ruud M. W Schemen, Rutger Dijsselhof, Ferdinand D. G. Kiestra, Ad. W A. de Man, Coert P. Petri, Jan Evert van Veldhoven, Erwin de Valk and Henry M. van Veldhuizen Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251 13.1 Energy Factory ............. . ....................... 252
13.1.1 The concept ................................. 252 13.1.2 The history ............. .. ................... 253 13.1 .3 The present state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254 13.1.4 Economic aspects .............. . .............. 255 13.1.5 The future (Wastewater management roadmap
towards 2030) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256 13.2 Cases ........................................ . ... 257
13.2.1 LNG production at 's-hertogenbosch . . . . . . . . . . . . . . 257 13.2.2 Thermophilie digestion at STP Echten ............. 262 13.2.3 Delivering biogas from STP Olburgen to
potato industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
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13.2.4 Centralised sludge treatment at STP Tilburg . . . . . . . . 264 13.2.5 Hydrolizing secondary sludge with TPH at
STP Venlo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 13.2.6 Digestion of external biomass at STP Apeldoorn ..... 266 13.2.7 Reclamation of energy and resources at STP
Amersfoort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 13.3 Conclusion(S) ...................................... 268 13.4 References ........................................ 268
Chapter 14 A new perspective on energy-efficiency and cost-effectiveness of sewage treatment plants . . . . . . . . 269 Helmut Rechberger and Aficja Sobaritka 14.1 lntroduction ........................................ 269 14.2 Methods and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
14.2.1 Application of eSEA for the assessment of the N-removal performance of STPs . . . . . . . . . . . . . . 271
14.2.2 Data of Austrian STPs . . . . . . . . . . . . . . . . . . . . . . . . . . 273 14.3 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
14.3.1 Assessment of the N-removal performance of STPs: eSEA vs N-removal rate . . . . . . . . . . . . . . . . . . . 274
14.3.2 Determination of the best practice STP: energy-efficiency and cost-effectiveness . . . . . . . . . . . 275
14.3.3 The influence of plant size . . . . . . . . . . . . . . . . . . . . . . 276 14.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 14.5 References .... . .. . ... . ...... .. ... . ................ 279
Chapter 15 Techno-economic assessment of sludge dewatering devices: A practical tool . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 Matteo Papa and Giorgio Bertanza 15.1 lntroduction ................................ . ....... 283 15.2 Description of the Methodology ................ . ........ 284
15.2.1 Operating procedure for test execution ............. 284 15.2.2 Data processing ... . ... . .. . ....... . ........... 288
15.3 Application to a Real Case Study ............ . ....... . .. 288 15.3.1 Technical issues . . ..... . .. . .. . .......... . ..... 289 15.3.2 Economic issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
15.4 Conclusions ..... . ....... . .. .... .................... 292 15.5 References ........ . ............................... 293
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Chapter 16 Short-cut enhanced nutrient removal from anaerobic supernatants: Pilot sca/e results and fu// sca/e deve/opment of the S.C.E.N.A. process . . . . . . . . . . . . . . . 295 Daniele Renzi, Stefano Longo, Nicola Frison, Simos Malamis, Evina Katsou and Francesco Fatone 16.1 lntroduction ........................................ 295
16.1.1 Removal or recovery? .......................... 296 16.2 Short-Cut Nitrogen Removal and
Via-Nitrite Enhanced Phosphorus Bioaccumulation: Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
16.3 Capital and Operating Cost of Anaerobic Sidestream Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 16.3.1 Energy consumptions and costs of short-cut nitrogen
removal from anaerobic sidestream . . . . . . . . . . . . . . . 298 16.4 S.C.E.N.A. System .................................. 301
16.4.1 Pilot-scale results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 16.4.2 S.C.E.N.A. system integrated in conventional
treatment of sewage sludge . . . . . . . . . . . . . . . . . . . . . 302 16.5 Conclusions ........................................ 306 16.6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Chapter 17 lnvestigation of the potential energy saving in a pilot-scale sequencing batch reactor . . . . . . . . . . . . . . . . . . . . . 311 Luca Luccarini, Dalila Pulcini, Davide Sottara and Alessandro Spagni 17.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
17.1.1 Sequencing batch reactors . . . . . . . . . . . . . . . . . . . . . . 312 17.1.2 Automation of sequencing batch reactors . . . . . . . . . . . 313
17.2 Description of the Case Study . . . . . . . . . . . . . . . . . . . . . . . . . . 314 17.2.1 Pilot plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314 17.2.2 Process monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 17.2.3 EDSS architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
17.3 Results ............................................ 320 17.3.1 Nitrification time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 17.3.2 Dissolved oxygen consumption ................... 322 17.3.3 Cost analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
17.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 17.5 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324 17.6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
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Chapter 18 Economic impact of upgrading biogas from anaerobic digester of sewage sludge to biomethane for public transportation: Case study of Bekkelaget wastewater treatment plant in Oslo, Norway . . . . . . . . . . . . . . . . . . . . . 327 Rashid Abdi Elmi and G. Venkatesh 18.1 lntroduction ....................... . ................ 327 18.2 Wastewater Treatment and Sludge Handling at
Bekkelaget WWTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330 18.3 Biogas Handling at Bekkelaget WWTP . . . . . . . . . . . . . . . . . . . 331 18.4 The Economics of the Upgrading Facility . ................ 333 18.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338 18.6 References ........................ . ............... 339
Chapter 19 A wind PV hybrid system for power supply of a sewage treatment plant in a small town in Southern Brazil . . . . . . 341 Giuliano Daronco and Alexandre Beluco 19.1 lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341 19.2 The Sewage Treatment Plant Considered in this Study ...... 342 19.3 Components of the Energy System .................... . . 345 19.4 Simulations with Homer ............................... 348 19.5 Results and Discussion ............................... 349 19.6 Final Remarks ....................... . ...... . ....... 353 19.7 References ..... . ..................... .. ........... 354