[ExI] cure for global warming

Keith Henson hkeithhenson at gmail.com
Mon Dec 27 19:43:44 UTC 2010


On Mon, Dec 27, 2010 at 12:11 AM,  Eugen Leitl <eugen at leitl.org> wrote:
>
> On Sun, Dec 26, 2010 at 10:43:38AM -0700, Keith Henson wrote:
>> > Fortunately we have better ways of resolving the energy crisis or looming crisis in the meantime.
>>
>> Oh?  Please explain.  I spent 3 years on reducing the cost of power
>> satellites and have worked the last year on StratoSolar.  The
>> fundamental problem with solar energy is that it is dilute and
>> intermittent.  Wind has the same problem.  Both require huge capital
>
> I don't think it's at all dilute.

Over a year solar energy averages a few hundred watts per square
meter.  Then you take the efficiency loss in the PV cells of at least
75%.

The inside of a power boiler is in the tens of MW, and the efficiency
is around 45%.  (60% for combined cycle.)

> Solar flux upon outer residential
> building skin is enough to power it. In fact, Si PV rather likes
> it cooler, so you need backventilation to make it approach optimum.

Powering houses is nowhere close to the whole energy problem.

> Many human activities are following diurnal cycles, and cheap nocturnal
> power is an artefact of large plant thermal inertia and dynamic market
> pricing. You can assume nocturnal demand will collapse if price
> was to double or triple.

I thought the object was abundant low cost energy.

> People need houses, these have outer building skins which need
> to be durable. Thin-film photovoltaics is an excellent way where
> construction material doubles up in function (in fact, CdTe
> has about an order magnitude more of energy supply equivalent than
> enrichened uranium in LWRs, not considering recycling).
>
> The prices are getting there, eventually. The hard part is making
> the growth match the demand gap, double and triple electrification,
> and build up electrosynthesis infrastructure for fuels and chemical
> feedstock. Work done there so far: nearly zero.

It's just chemistry, and well understood chemistry at that.

> I grant you this is hard, we're not doing nearly enough of that,
> and this is going to hurt. However, we do not have any other options.
>
>> costs that translate into high cost per kWh.
>
> I see lots of PV panels on farmer barns around here.

You will see fewer of them as the subsidies are being phased out.

> Not exactly
> huge capital costs, and the kWh prices are a factor of about 2
> removed from residential electricity prices. It looks like thin-film
> PV will become the cheapest electrical energy option for end consumers
> in less than a decade.

I really doubt it.

BillK <pharos at gmail.com> writes:

> Plus 'Passive house' and 'Zero energy house' designs.
> <http://www.passivehouse.us/passiveHouse/PassiveHouseInfo.html>
> Quote:
> A Passive House is a very well-insulated, virtually air-tight building
> that is primarily heated by passive solar gain and by internal gains
> from people, electrical equipment, etc. Energy losses are minimized.
> Any remaining heat demand is provided by an extremely small source.
>
> Over the last 10 years more than 15,000 buildings in Europe - from
> single and multifamily residences, to schools, factories and office
> buildings - have been designed and built or remodeled to the passive
> house standard.

What's the EU?  500 million people?  150 million houses?  In ten years
1 in 10,000 houses, at that rate 100,000 years to get them all done.

I think the energy crisis will be over by then.

John Clark <jonkc at bellsouth.net> worte
>
> On Dec 25, 2010, at 10:50 PM, Keith Henson wrote:
>>
>> The *easy* part is making a clean cheap substitutes for fossil fuels.
>> We know how to suck CO2 out of air at a cost of around 100 kWh/t (360
>> kWh per ton of carbon).
>
> I'm much more interested (and much more skeptical) in a dollars per ton figure than energy per ton.

It's the same thing with fuel.

http://htyp.org/Dollar_a_gallon_gasoline#Carbon_neutral.3F

And I'm not even certain CO2 is at the root of the problem, it
certainly isn't the most important greenhouse gas, water vapor is, and
water vapor is the very thing that current climate models handel so
poorly. I just have a hard time getting all worked up over the rise in
CO2, OK it has risen from 280 parts per million to 380 parts per
million over the last century, but 80 million years ago it was well
over 1000ppm and life got along just fine, plant did rather better
that they do now in fact. Plants like CO2, that's why commercial
greenhouses deliberately increase it to over 1400ppm. It's also
interesting that over the history of the Earth most CO2 increases seem
to come after a temperature rise and not before.

My point is that global warming, even if true, isn't the problem that
will kill billions.  Energy is.

>> We know how to make hydrogen either directly from heat (S I process)
>
> Where does the heat come from?

If we can build StratoSolar, it is a source of heat.  Or nuclear using
pebble bed reactors.

>> or by electrolysis.
>
> Even if the electricity came from solar cells that might not be good news for global warming; solar cells are designed to capture sunlight and thus are black, but only about 12% of the light is converted to electricity, so 88% is converted directly into heat.
>
>>> In another design that would probably be even cheaper he just slips a sleeve over the smokestack of any existing small to midsize coal power plant in the higher latitudes and uses the hot exhaust to fill hot air balloons to support the hose.
>>
>> It's a lot harder than you might think.
>
> Myhrvold is saying that if you want to cure global warming in the northern hemisphere then pick any existing medium sized coal power plant that is not too far from the arctic circle and simply extend the smokestack from 1000 feet its at now to 18 miles. That's it. That sounds a lot easier than a space elevator, or power satellites, or scrubbing the atmosphere clean of CO2; and that last might not even cool the planet, but thanks to Pinatubo we know for sure that sulphur dioxide in the stratosphere will.

Having worked for a year on a similar problem, I can tell you it isn't
that easy to keep a pipe up to 12.5 miles, much less 18.  You have to
deal with maximum wind.  It can get up to 50 m/sec and the drag goes
up as the square of the wind velocity.

Samantha Atkins <sjatkins at mac.com> wrote:

> The bottom line is that there is no good evidence of a dangerous amount of warming or hardly any statistically significant warming at all if you check variation over say the last several centuries.  OTOH we know for certain, or darn well should by now, that we are facing a major economic breakdown and pending energy crisis.  So why don't we, as rational future minded folks, focus our attention on the real problems and opportunities?

and

> True, when we have cheap efficient enough thin film solar.  However,  we have no reason to expect this to occur within this next crucial decade.  So on to the next solution for now.

Exactly.

Keith




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