What exactly is "renewable energy"?

Question

I'm pretty sure that wind and solar are two of the most prominent examples of "renewable energy" so let's stick with those for the purposes of this question. And I think we can agree that the word renewable is meant to be diametrically opposite of non-renewable energy, i.e. fossil fuels (and uranium).

It is clear that the Sun is a renewable source of energy. It will continue to fuse hydrogen into helium for the next several billion years and bathe the Earth with shortwave radiation. And the Sun powers the winds so they should be good as well. The Sun is good virtually forever while fossil fuels are going to run out eventually (if we keep using them). So far so good.

But we need to harness that wind and solar energy and convert it to useful electricity. Basically, this means we need to build wind turbines and solar panels. And that means we need materials. And we will keep needing materials because these machines don't last forever. Most materials are non-renewable, especially ones like rare earth elements. And there is a lot of energy expended to construct, transport, install and maintain renewable energy devices.

So is "renewable energy" actually an accurate term? Doesn't that really imply a perpetual motion machine?

Answer 1

I remember reading a book probably in the 1970s called the Third Wave by Alvin Toffler. In the book, the author made similar conclusions and defined oil, nuclear, and others as second wave because they were unsustainable forever (I can't remember if he used the word renewable). Fusion was the only thing that made the Third Wave if memory serves. I have heard studies that suggested that after you included the construction costs and everything that went into them, windmills made very little net energy. They are costly, ugly and deadly to birds as well as dependent on the wind which isn't always cooperative.



I sometimes go to a place near Happy Camp on the Klamath River. Environmentalists at EPA are seeking to remove all dams on the Klamath River and Happy Camp will then disappear forever. It seems that clean reliable energy isn't one of the priorities of these far leftists. They won't be happy until the ugly scar of humanity is wiped from the Earth.

Answer 2

Yes, "renewable energy" is not an accurate term, but if we're talking about solar-based energy then there is no reason it can't be used for billions of years. When you say "Most materials are non-renewable, especially ones like rare earth elements", I'm not sure what point you're making. Except in nuclear reactions, elements remain the same no matter how they're used. With adequate energy we can take scrap metals and refine them again--they're almost certainly going to have a higher content of what we're interested in than the original ores. As long as the energy required to make the devices is less than that provided by them, we can keep at it indefinitely.



By the way, as elements go, the rare earth elements are not particularly rare.

Answer 3

How about if renewable energy sources are expended to construct, transport and install these devices?? (Energy in the sense of "fuel" for machines).



Also many of the materials used to build these devices could be reused, recycled etc.



Renewable energy is in reference to the energy source.

Answer 4

Not exactly. "Renewable" in this case indicates that the energy can be replenished; just like trees are a renewable resource because we can plant more, solar power is renewable because more solar energy is coming. A perpetual motion device is a device in which no energy is lost or used. That is, as yet, impossible.

Answer 5

I understand your question and you have already answered it for yourself - "And I think we can agree that the word renewable is meant to be diametrically opposite of non-renewable energy, i.e. fossil fuels (and uranium)."



Perhaps you meant to inquire as to if anything will last forever?

Answer 6

I wonder if "Fodder" went to high school. All energy is made by Nature. Earth's energy comes from our sun, our falling water and tides, our minerals (coal, uranium) from Mama Earth, our food also, our building materials also.

The only thing that makes me curious about "something" outside the real world around us is our ability to think. We are able to question why we are here at all.

It doesn't drive me to some "God" nonsense, but it does make me ponder whether the Universe itself is somehow "alive"

Answer 7

The materials to build wind turbines and solar panels are recyclable.

Answer 8

The "renewable" in "renewable energy" is clearly meant in relative, not absolute, terms.



Like "liar." That word does not mean that absolutely every single single sentence uttered is demonstrably untrue. It does however mean, for instance, that the utterer has a deeply ingrained and repeatedly manifest tendency to actively and deliberately deceive: for example by recycling pre-fab anti-science tricks, myths, and deceptions in the form of fake questions, thousands of times on this website.

Answer 9

An energy that doesn't run out, like wind or solar energy

Answer 10

renewable energy

Answer 11

renewable energy is an energy that never runs out.

Answer 12

It's energy that can be renewed!

Answer 13

Energy that can be renewed

Answer 14

Do you think those materials we make those windmills and solar panels from are reusable to make new windmills from old windmills and new solar panels from old solar panels? If so are those items then not renewable?

Answer 15

just google it.