Green has become the common term for people who care about the environment or for practices promoted as better for the environment than some other practices. When used for marketing, “green” can become downright misleading. In fact, there’s a term “greenwashing” to describe advertising that makes something look greener than it really is.

Sustainable, on the other hand, refers to practices
designed to have the least impact on the environment, create the least waste, and capable of being carried out indefinitely. That is, something sustainable can’t waste resources, can’t pollute, can’t be dangerous over the long term to life, can’t cost so much that it causes social or financial disruption, etc.

The familiar recycling logo beautifully symbolizes the meaning of sustainability. The arrows point to one another in a never-ending cycle. There are various interpretations of it, but let’s take them to mean

1. Removal of as much material as possible from the waste stream
2. Manufacture of new products from the recycled waste
3. Sale and purchase of the new products
4. Use of the new purchases until such time as they wear out
5. Go back to the beginning of the cycle

If the cycle breaks at any point—if waste does not enter the recycling stream, if municipalities cannot sell recyclables to manufacturers, if consumers resist buying recycled products, etc.—the process becomes unsustainable.

To use a single example, solar power is generally considered “green.” That doesn’t mean it’s necessarily sustainable in the current state of technology and society.

Unsustainable solar power

Photographer’s caption: The rails that will hold the solar panels in place are up, and we are wrapping up at the end of Day 1 of installing the panels on a low-income house in Oakland, California.

Sunlight is free. Fossil fuels are not. There is no need to burn sunlight to make electricity. Burning fossil fuels causes air pollution and leaves a residue that, without careful disposal, causes water pollution. Solar power is greener than electricity generated from fossil fuels.

Plants turn sunlight into energy. Animal life depends directly or indirectly on this ability of plants. When plants or animals die, they break down and eventually become soil, which nurtures new plants. The ordinary life cycle on this planet is the ideal of sustainability to which human efforts are beginning to aspire.

So far, however, humans haven’t learned to make energy from sunlight without manufacturing sophisticated tools and machinery.

• Solar power requires solar panels made of silicon, which must be mined. So far, we haven’t developed sustainable mining practices.
• Solar power can directly operate a single item, such as a light or a fan, but it cannot directly power a house without an inverter. Besides whatever environmental impact is inherent in manufacturing panels and inverters, they eventually come to the end of their useful life. Will they then enter the recycling stream, or the waste stream that is overloading dwindling landfill space?
• Generation of solar power requires direct sunlight. Using solar power at night or in heavy clouds or fog requires storage batteries. Most of what I have read about batteries concern those needed for electric vehicles, which may or may not be similar. Those batteries require lithium, so-called rare earths, and other minerals that the US must import from places like China. Aside from China’s dismal environmental record, relying on China for raw materials is no more sustainable for us than relying on other geopolitical rivals for fossil fuels.

Solar panels with inverters provide power for buildings, which may or may not be tied into the power grid. Some power companies have also made deals with other industrial entities to install solar farms on otherwise unusable land. That power directly feeds the grid.

So far solar power amounts to only a small fraction of the electricity sold by power companies. It is not likely to account for a significantly greater fraction using the technology I have just described.

A solar technology that uses parabolic mirrors to concentrate sunlight boil water can generate as much power as a traditional power plant. Unfortunately, it requires vast amounts of land. Suitable sized tracts can generally be found only in deserts.

It is necessary to remove all vegetation, and therefore destroy the habitats of whatever animals live there. The construction equipment necessary to build such a vast project operates on diesel fuel and other applications of fossil fuels.

And then when the plant is ready to operate, somehow it must be supplied with the water necessary to operate the boilers. There is nothing remotely sustainable about parabolic mirror solar power as the technology now exists.

Beware of expecting perfection

Some environmentalists quickly denounce anything that appears to have any negative environmental consequences at all. I’m always surprised every time I hear anyone complain that manufacturing goods using recycled materials contributes to some kind of pollution. Mankind has yet to learn to make much of anything more sophisticated than simple crafts that has no environmental or health downside.

Solar power using flat panels, inverters, and storage batteries may not be perfect, but it still seems preferable to destroying the landscape to mine coal and then fouling the air and water by burning it. If mining operations are inherently dangerous to both the miners and the local environment, there appears to be no product more dangerous than coal.

Solar power is green. It will become more and more sustainable as advancing technology provides safer mining and manufacturing techniques, more efficient solar collectors than the current flat panels, etc. And as techniques of reclaiming and remanufacturing spent equipment, along with awareness among the equipment’s owners, keep it out of landfills.

Meanwhile, when designing a new building, here’s the way to build the most sustainable electric power into it: design it to take maximum advantage of passive solar power.

Useful links:
Earth-Friendly Elements, Mined Destructively / by Keith Bradsher in New York Times
Shameful . . . , a thread on The Green Living Forum
Photo credits:
Installing home solar. Some rights reserved by Lauren Wellicome.