Prospective CO2 emissions from energy supplying systems: photovoltaic systems and conventional grid within Spanish frame conditions
- 369 Downloads
Background, aim, and scope
In order to assess the environmental sustainability of a novel wastewater treatment process based on power an electrochemical reactor by photovoltaic solar modules (photovoltaic solar electrochemical oxidation), a life cycle approach was considered to quantify the CO2 equivalent (CO2-eq.) emissions coming from the two supplying power systems to the electrochemical process: conventional grid power or photovoltaic solar power under Spain frame conditions.
Materials and methods
GaBi 4 software was used to build models to characterize the conventional grid and photovoltaic power generation (corresponding functional unit, 1 kWh). ecoinvent v2.0 was chosen to consider background data. Nine different 2030 scenarios were evaluated versus 2007 reference values to take into account: (a) the progressive change to a greener grid mix in Spain and (b) the improvements in photovoltaic solar technology.
The results showed that, under the nine considered scenarios for 2030, the CO2-eq.per kilowatt hour emissions are always lower than the reference values for 2007 (reductions around 60%). Additionally, the results showed that 2030 values for the CO2-eq.per kilowatt hour emissions coming from the use of photovoltaic modules for power generation are expected to be around 60% lower than for 2007 values.
In order to power an electrochemical process, the direct use of photovoltaic solar energy will give much lower CO2-eq.per kilowatt hour emissions than the supply from conventional grid.
A quantitative study based on life cycle assessment has compared the CO2-eq.per kilowatt hour emissions coming from supplying an electrochemical reactor by conventional grid and by photovoltaic solar modules under Spanish frame conditions and stated that the novel process photovoltaic solar electrochemical oxidation would be a preferred environmental option due to the lower CO2-eq.per kilowatt hour emissions under present and future scenarios.
Recommendations and perspectives
The results would suggest that it is worthy to explore not only the possibilities of this technology but also other electrochemical technologies that can be supplied directly by electricity in order to have a better sustainability performance.
KeywordsCarbon footprint Electrochemical oxidation Grid mix Photovoltaic solar energy Solar technology Spain Wastewater treatment
- ASIF (2008) Towards a sustainable electricity supply. The solar photovoltaic energy in Spain, Annual Report 2008 (‘Hacia un suministro sostenible de la electricidad. La energía solar fotovoltaica en España. Informe Anual 2008’). Asociación de la Industria Fotovoltaica Española. http://www.asif.es
- ecoinvent (2008) The life cycle inventory data version 2.0. Swiss Center for Life Cycle Inventories. http://www.ecoinvent.ch
- EPIA (2008) EPIA/production (relative share of technology over time). http://www.epia.org/datafigures/production.html. Accessed in 2009
- EPIA and Greenpeace (2008) Solar generation V-2008 solar electricity for over billion people and two million jobs by 2020. http://www.epia.org
- EUPVTP (2007) A strategic research agenda for photovoltaic solar energy technology. Working Group 3 ‘Science, Technology and Applications’ of the EU PV Technology Platform. Under Sixth Framework Programme, contract nº: 513548Google Scholar
- Frankl P, Menichetti E, Raugei M (2005) Final report on technical data, costs and life cycle inventories of PV applications. Under Sixth Framework Programme, Project nº: 502687. NEEDS New Energy Externalities Developments for Sustainability, Deliverable nº 11.2-RS IaGoogle Scholar
- GaBi (2008) GaBi 4 software-system and databases for life cycle engineering. Chair of Buildings Physics (University of Stuttgart), PE International. http://www.gabi-software.com
- IChemE (2007) A roadmap for the 21th century chemical engineering. Institution of Chemical Engineers. http://www.icheme.org/roadmap2007.pdf
- IDAE (2005) Plan for renewable energies in Spain 2005–2010 (‘Plan de energías renovables en España 2005–2010’). http://www.mityc.es/energia/desarrollo/EnergiaRenovable
- ISO (2006a) Environmental management. Life Cycle Assessment. Principles and framework (ISO 14040:2006). International Organization for Standardization, GenevaGoogle Scholar
- ISO (2006b) Environmental management. Life Cycle Assessment. Requirements and guidelines (ISO 14044:2006). International Organization for Standardization, GenevaGoogle Scholar
- NREL (2007a) National Solar Technology Roadmap: wafer-silicon PV, management report NREL/MP-520-41733 draft version. http://www1.eere.energy.gov/solar/solar_america
- NREL (2007b) National Solar Technology Roadmap: film-silicon PV, management report NREL/MP-520-41734 draft version. http://www1.eere.energy.gov/solar/solar_america
- NREL (2007c) National Solar Technology Roadmap: CdTe PV, management report NREL/MP-520-41736 draft version. http://www1.eere.energy.gov/solar/solar_america
- NREL (2007d) National Solar Technology Roadmap: CIGS PV, management report NREL/MP- 520-41737 draft version. http://www1.eere.energy.gov/solar/solar_america
- Pfatischer R (2008) Evaluation of predicted and real operational data of different thin-film technologies. In: Proceedings from: OTTI Thin Film User Forum—28.01.2009, Würzburg, Germany. http://energie.otti.de/thin_film_photovoltaics
- PVGIS (2008) Photovoltaic Geographical Information System (PVGIS). Geographical Assessment of Solar Resource and Performance of Photovoltaic Technology. http://http://sunbird.jrc.it/pvgis/. Accessed in 2008
- Raugei M, Frankl P, Alsema E, de Wild-Scholten M, Fthenakis V, Kim HC (2007) Life cycle assessment of present and future photovoltaic systems. In: Proceedings from: AIST Symposium ‘Expectations and Advances Technologies in Renewable Energy’. Chiba, JapanGoogle Scholar
- REE (2008) The Spanish Electrical System 07 (‘El Sistema Eléctrico Español 07’). Red Eléctrica de España. http://www.ree.es
- SGE (2008) The Energy in Spain 2007 (‘La Energía en España 2007’) Secretaría General de Energía, Ministerio de Industria, Turismo y Comercio, Gobierno de España. http://www.mityc.es
- UNESA (2007) UNESA’s outlook for electricity generation for 2030 (‘Prospecciones de Generación Eléctrica 2030’). Asociación Española de la Industria Eléctrica. http://www.unesa.es
- Viebahn P, Nitsch J, Fischedick M, Esken A, Schüwer D, Supersberger N, Zuberbühler U, Edenhofer O (2007) Comparison of carbon capture and storage with renewable energy technologies regarding structural, economic, and ecological aspects in Germany. Int J Greenh Gas Control 1(1):121–133CrossRefGoogle Scholar