Environmental Engineering Reference
In-Depth Information
Conclusion 2:
We are headed toward a (nearly) all-renewable-energy economy one way or the oth-
er, and planning is essential if we want to get there in one piece.
If society is to avoid civilization-threatening levels of climate change, the use of fossil fuels will
have to be reduced proactively by 80-90 percent by 2050.
2
At the same time, despite the claims of abundance of unconventional fuels (shale gas, tight oil,
tar sands) by the fossil fuel industry, evidence overwhelmingly shows that drillers are investing in-
creasing effort to achieve diminishing returns.
Either way, fossil fuels are on their way out.
Most nations have concluded that nuclear power is too costly and risky, and supplies of uranium,
the predominant fuel for nuclear power, are limited anyway. Thorium, breeder, fusion, and other
nuclear alternatives may hold theoretical promise, but there is virtually no hope that we can re-
solve the remaining myriad practical challenges, commercialize the technologies, and deploy tens
of thousands of new power plants within just a few decades.
That leaves renewable energy sources—solar, wind, hydro, geothermal, tidal, and wave
power—to power the economy of the future.
Conclusion 3:
In the process of transition, the ways that society
uses
energy must change at least
as much as the ways society
produces
energy.
Every energy source possesses a unique set of characteristics: some sources are more portable
than others, or more concentrated, intermittent, scalable, diffuse, renewable, environmentally risky,
or expensive. We have built our current economy to take advantage of the special properties of
fossil fuels. The renewable energy sources that are available to replace oil, gas, and coal have very
different characteristics and will therefore tend to support a different kind of economy—one that
is less mobile, more rooted in place; less globalized, more localized; less when-we-want-it, more
when-it's-available; less engineered, more organic.
At the same time, the sheer
quantity
of energy that will be available during the transition from
fossil to renewable sources is in doubt. While ever-more-rapid rates of extraction of fossil fuels
powered a growing economy during the 20th century, society will struggle to maintain current
levels of total energy production in the 21st, let alone grow them to meet projected demand. Indeed,
there are credible scenarios in which available energy could decline significantly. And we will have
to invest a lot of the fossil energy we
do
have in building post-fossil energy infrastructure. Energy
efficiency can help along the way, but only marginally.
The global economy will almost certainly stagnate or contract accordingly.
There it is. It is a complicated message. I've just conveyed it in under seven hundred words
punctuated by three short summary sentences. (And here's a summation of the summation: it's all
about energy; renewables are the future; growth is over.) However, only readers with a lot of prior
knowledge will be able to truly understand some of these words and phrases. And many people who
are capable of making sense of what I've written would disagree with, or dismiss, much of it. The
message faces a tough audience, and it flies against deep-seated interests.
Many economists and politicians don't buy the assertion that energy is at the core of our species-
wide survival challenge. They think the game of human success-or-failure revolves around money,
military power, or technological advancement. If we toggle prices, taxes, and interest rates; main-
tain proper trade rules; invest in technology research and development (R&D); and discourage
military challenges to the current international order, then growth can continue indefinitely and
