SOLAR CELLS BEATS FOSSIL FUELS AGAIN

More good news for solar energy: A new Brookhaven National Labs study concludes the fears that solar cell manufacture creates more toxicity than it resolves are unfounded. A switch from fossil fueled power plants to solar cells would dramatically reduce air pollution: “Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.”

Manufacture of photovoltaic cells involves toxic metals (ex: lead, mercury, cadmium) and generates climate change-inducing greenhouse gases. But fossil fuels also release heavy metals and much worse greenhouse gases when they are burned to generate power.

Most of the toxic emissions from solar cell manufacturing are due to fossil fuel-burning power plant emissions that provide the electricity for the solar cell plants. When solar cell plants run on solar energy it will be what the head researcher in the study called "…a self-sustained process…" The more popular term for that is “sustainable.” It is the goal.

click to enlarge

Easing Concerns About Pollution From Manufacture Of Solar Cells
February 26, 2008 (American Chemical Society via Science Daily)
and
Solar Power’s Greenhouse Emissions Measured
Charles Q. Choi, February 27, 2008 (LiveScience via Yahoo News)

WHO
Vasilis M. Fthenakis w/Hyung Chul Kim and Erik Alsema, Brookhaven National Laboratory; 13 solar cell manufacturers

click to enlarge

WHAT
Emissions from Photovoltaic Life Cycles concludes: Manufacturing solar cells produces far fewer air pollutants than conventional fossil-fuel-burning power plants.

WHEN
- This is the first study on the pollutants produced during the manufacture of solar cells.
- It covers the period 2004-2006.

WHERE
- The study is published in the March 15 issue of the ACS' Environmental Science & Technology
- The 13 solar cell manufacturers studied were located in Europe and the United States.
Brookhaven National Laboratory is in Upton, NY.

The more electricity comes from solar energy -- silicon or cadmium telluride (CdTe) -- the more emissions and toxicity fall. (click to enlarge)

WHY
- Manufacturing processes for four major commercial types of solar materials were studied: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride.
- A statistical evaluation of air pollution emissions data showed the manufacture of solar cells cuts air pollutants 89%.

QUOTES
Vasilis Fthenakis, researcher/environmental engineer, Brookhaven National Laboratory: "One of the most promising photovoltaic technologies is based on cadmium telluride, but cadmium is one of the worst heavy metals. Still, if we compare direct emissions from production of cadmium telluride cells with coal power plants, toxic emissions would up 300 times lower…"