Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Waste could generate up to 7 percent of electricity in Spain

23.02.2010
Researchers from the University of Zaragoza (UNIZAR) have calculated the energy and economic potential of urban solid waste, sludge from water treatment plants and livestock slurry for generating electricity in Spain. These residues are alternative sources of renewable energy, which are more environmentally friendly and, in the case of solid urban waste, more cost effective.

Using waste to generate electricity has economic and environmental advantages. "It gives added value to waste, because it can be seen as a type of fuel with zero cost, or even a negative cost if taxes are paid to collect it", Norberto Fueyo, lead author of the study and a researcher at the Fluid Mechanics Group of the UNIZAR, tells SINC.

According to the researcher, generating electricity from waste avoids "pernicious" impacts. Waste in landfill sites releases methane and other polluting gases, so incinerating solid urban waste will reduce the volume of waste that reaches the landfill sites in the first places, as well as the implicit risks of landfills themselves (possible emission of methane into the atmosphere).

The study, published in the latest issue of the journal Renewable Energy, has shown that waste in Spain could generate between 8.13 and 20.95 TWh (terawatt hours). "This electricity generation was 7.2% of electricity demand in 2008", says Fueyo.

The researchers stress that the amount of methane generated from different kinds of residues is equivalent to 7.6% of gas consumption in 2008.

In terms of the economic cost, "solid urban waste is the most cost-effective", according to the researcher, because local authorities carry out the waste collection and local inhabitants pay for it. Since the waste is transported to large landfill sites or waste treatment plants, installing electricity generation systems "could take advantage of economies of scale due to the large volumes involved".

Cost depends on the heat generated

According to the study, incineration of waste and degasification of landfill sites are the electricity generation technologies with lowest financial cost. Producing electric energy through anaerobic digestion (a biological process in which organic matter decomposes into biogas in the absence of oxygen and through the action of a group of specific bacteria) is much more expensive.

"However, its profitability relies on being able to get value out of the heat generated during the process", explains Fueyo, who says this technique is "not competitive, but makes use of the heat to offset the costs of generation". However, the researchers point out that "directly applying this waste to agricultural land as fertiliser could contaminate groundwater with nitrates".

In order to evaluate the potential and the cost of generating electricity, the researchers applied the methodology in municipal areas (in the case of solid urban waste and sludge from water treatment plants) and regional areas (for livestock slurry) throughout the whole of Spain.

The work shows that the centre and south of the Iberian Peninsula, the Balearic and Canary Islands have the "greatest interest" in putting technologies into place to use solid urban waste.

In terms of using water treatment plant sludge, the coastal areas of Galicia. Valencia and Alicante, as well as central and southern Spain, were also areas of interest. The study also shows that certain areas of Aragon, Castilla-La-Mancha, Castilla-y-León, Extremadura, Galicia and Andalusia "would be effective" for using livestock slurry.

The EU 20-20-20 package

The research into electricity generation comes in response to the European Union (EU) objective to fulfil the 20-20-20 package for the year 2020, in other words to substitute 20% of the total energy consumed in Spain for energy from renewable resources, reduce CO2 emissions by 20% in comparison with 1990 figures, increase biofuels used in transport by 10%, and achieve energy savings of 20%. "For Spain, each one of these targets alone is a challenge, which becomes much bigger when they are all taken together", underscores the scientist.

Norberto Fueyo says the most problematic objective is that relating to increasing the amount of biofuels used in transport by 10%. "It is not achievable and is socially and environmentally questionable, because of the amount of land it requires and because it means using foodstuffs to produce fuel".

Even if the figure of 10% of biofuels in transport is achieved, "there will need to be an increase of around 45% in the contribution of renewables (including hydroelectric energy) to electricity generation in order to achieve a figure of 20% of renewable energy within total consumption", the expert says. The scientist adds that, in order to achieve the objective, it will be "essential" to promote energy saving and efficiency "and consider all possible sources of renewable energy, including waste".

References:

Gómez, Antonio; Zubizarreta, Javier; Rodrígues, Marcos; Dopazo, César; Fueyo, Norberto. "Potential and cost of electricity generation from human and animal waste in Spain" Renewable Energy 35(2): 498-505, febrero de 2010.

SINC | EurekAlert!
Further information:
http://www.plataformasinc.es

More articles from Power and Electrical Engineering:

nachricht Large-scale battery storage system in field trial
11.12.2017 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

nachricht New test procedure for developing quick-charging lithium-ion batteries
07.12.2017 | Forschungszentrum Jülich

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>