but there is so much of it in the earth’s crust and it is so efficiently recycled that there is enough for at least tens of thousands of years, perhaps millions. Lead, zinc, copper, and coal are also very abundant and not likely to become scarce any time soon. Uranium and thorium, both of which can produce nuclear energy, are in sufficient supply to last thousands of years.
It is more important for a resource to be sustainable than it is to be renewable. And even renewable resources require nonrenewable resources to operate. Solar panels are made from aluminum, silicon, and gallium arsenide. Wind turbines require a lot of steel and concrete for their towers (about five times as much, per unit of energy produced, compared to a nuclear power plant).
Now we come to green , the most elusive and least precise of the four terms. Green is the most political term, as it tends to reflect personal biases and opinions as much as objective and measurable criteria. At its worst, green is a shameless marketing slogan, used to promote various products and services as environmentally friendly. Yet it is a useful term, a way of distinguishing relatively damaging technologies from ones that have less impact, if it is used objectively.
But green is very much in the eye of the beholder. We have green jobs, green energy, green buildings, Greenpeace and Greenspirit. Green includes renewable, sustainable, and clean. “Greens” believe in green attributes but disagree widely on what should be included in the category. Many Greens oppose hydroelectric energy even though it is the largest source of renewable electricity. Many Greens oppose nuclear energy even though it is sustainable and clean. And many Greens oppose or frown on forestry even though it provides our most abundant renewable energy and material resource. Solar panels and wind farms are considered green despite the fact that they are made with nonrenewable materials, some of which cause large greenhouse gas emissions when they are produced. Concrete is a prime example. I conclude that green is more of a political or marketing term than a scientific one and therefore refrain from using it when renewable, sustainable, or clean will do. If asked what green means to me, I would say it must pass the test of being sustainable and clean.
The term greenwashing has been adopted by environmentalists to describe communications, particularly from corporate interests, which they contend are misleading the public. There are plenty of good examples of corporate greenwashing. “Clean Coal” is my favorite case in point. But the characterization of solar panels as being green might also be questioned. How can a technology that costs 10 times as much as conventional electricity and that is made entirely of nonrenewable resources be green? How can windmills be green when they require five times as much steel and concrete per unit of power produced compared to nuclear plants and when they occupy vast areas of land? One might ask if the pot is not calling the kettle black in the war of words over what green really means.
Facts, Correlations, Causes, and Predictions
The headline screams:
“PHTHALATES LINKED TO ABNORMAL GENITALIA IN BABY BOYS.”
First thought, What on earth is a phthalate? (The ph is silent and the first a is soft, so just say thallate. ). Phthalates are a class of chemical used as softeners in vinyl (polyvinyl chloride, or PVC) products. Pure vinyl, such as the PVC pipe used for water lines, is rigid. Vinyl is unique in that it can absorb many other elements and compounds, giving it properties that cannot be attained in other plastics. Your credit cards are made of vinyl; they are not brittle because they contain a small amount of phthalate. Other flexible vinyl products include vinyl flooring, blood bags and vinyl tubing, vinyl upholstery, vinyl records, and insulation on wiring to name a few. Phthalates are one of the most tested chemicals we use and have been cleared of
David Stuckler Sanjay Basu
Aiden James, Patrick Burdine