Do the benefits of renewable energy sources stack up?

August 13, 2007

Do the overall efficiencies of renewable energy sources, such as wind, solar, and geothermal add up in terms of their complete life cycle from materials sourcing, manufacture, running, and decommissioning? Researchers in Greece have carried out a life cycle assessment to find the answer.

Increasing energy consumption and a growing world population implies shrinking reserves of fossil fuels. While the use of fossil fuels brings with it the problem of carbon dioxide emissions and climate change. Our continued dependence on fossil fuels coupled with the pressing global issue of climate change has pushed the concept of renewable energy sources to the top of the agenda.

In looking for alternative energy supplies, there is more to simply adding up the outputs, according to Christopher Koroneos and Yanni Koroneos of the Laboratory of Heat Transfer and Environmental Engineering, at the Aristotle University of Thessaloniki, Greece. They argue that a whole life cycle assessment of any environmentally friendly energy supply must be carried out to ensure its green credentials are valid.

Writing in Inderscience's International Journal of Global Energy Issues, the researchers point out that land use and materials employed are just two aspects of renewable energy development that can have an adverse impact on the otherwise positive environmental picture.

There are three viable renewable energy resources, say the researchers - solar energy, wind power and geothermal energy. They have applied the techniques of life cycle assessment (LCA) to each in order to determine the total environmental impact and to compare this with the effects of equivalent energy release from fossil fuels.

The LCA approach allows an assessment to be made of the flow of material and energy used in the construction, operation and ultimate decommissioning of a renewable energy supply. It also takes into account the manufacturing of components, the possible extraction and supply of fuels as well as waste generated in these processes.

The researchers demonstrate that some renewable energy systems based on wind power and geothermal energy do have valid green credentials in electricity production. The efficiency of these systems is comparable over the complete life cycle than the equivalent fossil fuel system. However, the conversion of solar energy to electricity using photovoltaic solar cells is less efficient in terms of materials production, running, and recycling than non-renewable energy. However, economies of scale come into play with solar power and a large enough area of solar cells would outstrip the fossil fuel system. The team also points out that the life cycle pollution of solar systems is much, much lower than any conventional system although thermodynamic efficiency is lower.

"A significant advantage of the use of renewable energy systems," say the researchers, "is that they are environmentally friendly because overall they result in lower dangerous pollutant emissions, this and one other major factor, they are essentially inexhaustible."

Source: Inderscience Publishers

Explore further: NADINE: Power-plant-scale energy storage

Related Stories

NADINE: Power-plant-scale energy storage

October 18, 2018

On the way toward a CO2-neutral energy system, storage of large amounts of energy is still an unsolved problem. In the future, Karlsruhe Institute of Technology (KIT), the German Aerospace Center (DLR), and Stuttgart University ...

Could cutting CO2 emissions provide water during droughts?

October 16, 2018

Power plants provide homes and businesses with electricity on a daily basis. But plants also consume a daily essential: Water. In fact, the US electrical power industry uses nearly half of all water in the country. Power ...

Taxing carbon may sound like a good idea, but does it work?

October 15, 2018

Exxon Mobil is backing a proposal to tax oil, gas and coal companies for the carbon they emit and redistribute the money raised that way to all Americans. It's also giving a group urging Washington to enact a tax on carbon ...

Recommended for you

Evidence of earliest life on Earth disputed

October 17, 2018

When Australian scientists presented evidence in 2016 of life on Earth 3.7 billon years ago—pushing the record back 220 million years—it was a big deal, influencing even the search for life on Mars.

Arctic greening thaws permafrost, boosts runoff

October 17, 2018

A new collaborative study has investigated Arctic shrub-snow interactions to obtain a better understanding of the far north's tundra and vast permafrost system. Incorporating extensive in situ observations, Los Alamos National ...

Arctic ice sets speed limit for major ocean current

October 17, 2018

The Beaufort Gyre is an enormous, 600-mile-wide pool of swirling cold, fresh water in the Arctic Ocean, just north of Alaska and Canada. In the winter, this current is covered by a thick cap of ice. Each summer, as the ice ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.