NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/sci/energy/5672

Text File | 1992-11-20 | 10.2 KB | 184 lines

Newsgroups: sci.energy
Path: sparky!uunet!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv!gary
From: [e-mail] (Gary Coffman)
Subject: Re: Renewable energy from the sun
Message-ID: <[e-mail]>
Reply-To: [e-mail] (Gary Coffman)
Organization: Gannett Technologies Group
References: <[e-mail]> <[e-mail]> <[e-mail]> <[e-mail]> <[e-mail]>
Date: Fri, 20 Nov 1992 05:56:42 GMT
Lines: 172

In article <[e-mail]> [e-mail] (C Revie) writes:
>
[I wrote]
>>Your naive faith in the power of government directed R&D is touching,
>>but there is *no* assurance that *any* amount of R&D funding can break
>>fundamental Carnot limits on the low grade energy of diffuse sunlight.
>
>I'm not suggesting for one minute that by throwing money at the problem
>we will be able to change physical laws, or subvert them or whatever. I
>was just trying to point out the imbalance in research.

It's a common thread among many posters with an environmentalist slant
that *their* pet alternate energy mode would be successful *if only*
more *government* money was spent on it. Unfortunately, the economic
engineering realities are that most of these systems are uncompetitive
and will remain so as long as oil is cheap. And oil *is* historically
cheap right now. Which is lucky for us considering the delicate state
of the world economy. An energy price shock right now, caused by taxes,
world politics, or regulation, is very likely to send the world economy
into a very dangerous tailspin worse than 1929.

The one thing that government is absolutely worst at is in promoting
good hard headed cost effective engineering. That's what's needed to
bring some of the alternatives to market in a competitive position.
Some of the alternatives just can't become cost effective because of
rather fundamental limitations, but a few can be tapped competitively.
Little or no *research* is needed to achieve this, but lots of cost
conscious engineering needs to be done. The government isn't good at
this. Big, well funded, corporate R&D operations, most in aerospace,
aren't good at this. It's generally the small, aggressive, market
driven companies operating on a shoestring that are good at this.
Ironically, feeding them more funds is often the *worst* thing you
can do to enhance their productivity.

>Two Words - Radioactive waste. Without trying to be prejudiced, it is a
>problem. Yes the effects on greenhouse gas emissions would be
>beneficial, but at what price?

A very small price actually. If all the spent fuel from all the
commercial reactors in the world generated since the start of
commercial nuclear power were put in one place, it would cover a
football field to the depth of 1 meter. That's not a good idea because
it might go critical, but you get the idea. The volume is really small
compared to nearly any other industrial process you care to name.
Since nearly all the waste is solid, or can be made solid by proven
processes, disposal in a dry vault for 500 years is sufficient to
bring the radiation level down to the level of the ore that was
originally dug out of the ground. [Note: waste from military programs
is another matter and much more serious due to the sheer volume and
the poor handling and disposal procedures practiced during the time
most of it was generated. Low level waste is also fairly high volume,
but also rather low risk.]

Now contrast that with the effuvia of a coal powered generating station.
In *routine* operation, it releases more radioactivity into the air
than a routinely operating nuclear plant. In *routine* operation, it
generates hundreds of thousands of tons of toxic flyash, sulphur, heavy
metals, and the like each year. Unlike radioactive materials, these
dangerous toxics *never* decay.

Now naive environmentalists say we should stop *both* energy technologies
and go to "conservation energy" and solar energy. But they never produce
any believable environmental or *economic* impact statements for their pet
projects and their timetables for conversion are hopelessly optimistic.
If we want to make a *marked* difference in environmental cleanliness
in the next couple of decades, we need to be pushing nuclear power to
replace coal plants. We're not going to be able to cost effectively
divorce ourselves from central stations and the grid for a long time,
if ever, so we *have* to make the grid as clean as we economically can.

In addition, there are niche markets *today* where other alternatives
are cost competitive, or nearly so, at certain sites. These should be
exploited, but only where they make sense. Our "one size fits all"
mentality is often wrong. And pushing a cost *ineffective* solution
is always wrong.

>>>As the population grows, living within the capacity of the planets
>>>systems will become more important, a move to solar tecnologies is thus
>>>of prime importance.
>
>>That hasn't been proven. Indeed it is just an article of faith in some
>>quarters.
>
>Yes but equally it has not been proven that this is not the case. And
>I'd rather not carry out some giant experiment to prove it either way.

But that's exactly what you're saying when you want to move right away
to solar technologies en mass. One size does not fit all. Lots of processes
and lots of infrastructure are dependent on the current mix of cheap high
quality energy. It would cost gigabucks to change over and cause massive
social dislocation in the process. The alternatives have to be introduced
gradually, and only where appropriate.

One of the favorite uses of direct solar is passive space heating for
dwellings. Now retrofitting the US housing stock isn't either practical
or cost effective in most cases. Solar will have to come mainly in new
contstruction. That means it's 30 to 50 years down the road at best before
solar picks up a major share of space heating. Domestic hot water is a
different story. It is cost effective *now* in some climates as a retrofit.
It's cost effective nearly everywhere in new construction. On the other hand,
the aluminum industry, the steel industry, and most other manufacturing
aren't going to be able to convert to direct solar any time in the foreseeable
future.  They need cheap concentrated energy for their processes and their
plants last a long long time. Their plants are also often located in places
where wind, wave, and direct sun aren't readily tappable. If they are forced
to relocate, there would be large social disruptions. The Sunbelt/Snowbelt
crisis is already bad enough as it is without throwing this on the fire.

>At the
>moment the G7 nations account for a very large proprtion of energy use
>in the world (I'm sorry I'don't have exact figures to hand). 7 countries
>out of over 150 (ok some of these are very small). But nations China and
>India have nearly 2 billion people between them, just under half the
>present population of the planet! Imagine that these two countries raise
>their energy consumption per capita to something like Uk or the USA?
>Under these conditions a 100 fold increase in present energy consumption
>is quite likely.

Yes that's true. Fossil can't meet that demand with acceptable cost for
any length of time. Cheap supplies aren't that great and environmental
costs are high. Direct solar can't pick up that load either at an
acceptable cost for high quality energy requirements. Nuclear can,
and geothermal might.

>Solar technologies include very simple and easy to use ideas and
>techniques, which can be used now. There is potential in fusion but
>current estimates are that it will not be available as a viable source
>of power for 40 - 50 years.

I don't hold out much hope for controlled fusion, it always seems to be
40-50 years away. It's a possibility we shouldn't overlook, but not to
the exclusion of *proven* technologies like nuclear fission . Direct solar
for space heating is such a good idea the ancient Romans used it. Our
architects have ignored it in favor of "one size fits all" mechanical
solutions in recent years. That should change, but it's not a quick
fix bandaid. It will have to come as the housing stocks turn over.
That's a long way out too, and will cause considerable land use
changes as well. Direct solar applications are very site specific
in their implementations.

Wind energy, indirect solar, is also site specific as well as sporadic.
Other indirect solar technologies such as ocean thermal and hydropower
are also site specific. For industry and transport, where dependable,
high quality, compact energy sources are required, direct solar can be
only a very minor player. With an improved grid, many diverse minor
players aren't a bad thing. The costs of restructuring the grid must
be included in calculations, however, as well as the dispersed maintenance
costs and land use costs of many small plants.

Aside from nuclear fission plants, the other major non-solar player is deep
dry geothermal energy. Like solar, that's also primarily nuclear energy.
This time radioactive decay rather than fusion. And like solar, the
actual radioactive processes are divorced from site of use. That tends
to make it acceptable to a fearful public. Unlike wet geothermal, which
is available only in limited areas, dry geothermal is available anywhere
you are willing to drill deep. Thanks to vigorous development by the
oil industry, we have most of the tools to tap this heat. Much development
remains to be done, but dry geothermal holds the promise of electricity
nearly as cheap and controllable as that from nuclear fission plants,
and with a similarly low level of environmental effects.

Our technical civilization has become dependent on flipping the switch
and having energy ready at our command at any time. Stepping back from
that would have huge economic and social costs. Direct solar can only
meet a part of that requirement economically. Indirect solar currently
meets the bulk of our energy needs through fossil and hydropower, but
we've tapped much of the easily available hydropower, and fossil is both
limited and has undesirable environmental effects in high concentrations.
We still need other sources of high quality energy to meet demand. Going
solar is only a part of the energy picture.

Gary