Subject: Re: Solar Energy

From: [email-masked] (Nick Pine)
Date: 21 Sep 1995 11:16:07 -0400

Stephen Lajoie <[email-masked]> wrote:
>Will Stewart  <[email-masked]> wrote:
>>[email-masked] writes: 
>>>[email-masked] (Nick Pine) writes:

I do? I don't see anything quoted below that I wrote. Perhaps the >>>s
got confused somewhere... But as long as I'm here...

>>Kindly provide information showing the areas of the country that are
>>subject to two straight weeks of rain in a given year.  Now, what
>>percentage of the country is that?

I dunno. 30%? We seem to get 2 weeks of cloudy weather in January fairly
often around Philadelphia. Who cares, and why?

>At what reliability? We are talking probabilities here. How many sigma do
>we want to go out? And it doesn't have to be just rain; it can be simply
>cloud cover, snow cover or fog.

I'd like to know more about that. Norman Saunders, PE, estimates yearly backup
heat requirements of his solar houses based on house heating loads, the size
of the thermal store, and Gaussian weather statistics. I don't understand his
method, but his "100% solar houses" are nearly so, with predictions of backup
heating required every 40 years, in New England. Some of them have no backup
heating systems at all. He has elaborate temperature records from data logger/
fan controllers in these houses, with track records going back over 12 years.
This is sort of like 100 year flood predictions, with less dire consequences,
like having to wear a sweater indoors once every 40 years :-)

He doesn't use PVs or solar thermal panels, just glass, containers of water,
fans and insulation. I'd rather use plastic instead of glass, and I think
one could do almost as well without the fans, but it would cost more to build.

>[Cloudy weather] happens on a regular basis in these areas. It has less 
>of a probability in other areas but it CAN happen ANYWHERE, it is just a 
>matter of probability.

Then let's treat it as such, with numbers. It's not a disaster. It just
increases one's backup heating bill a bit. How much? Or drives purists to
wearing sweaters indoors. How often? I'd like to see numbers, not hand-waving.

>Maybe for the unreliable systems you envision, yeah, you don't have too
>many areas. But if you are trying to match the reliability of the grid,
>that would be another story. 

I think of the sun as fairly reliable. Moreso than the electrical grid.
It's been working longer, with no serious outages lately, and no major
repairs. It is very predictable, on a long time scale, and it seems to me 
that with proper statistics and careful design, we can build more houses
with thermal storage, that do not have any other form of heat. These might
be called "solar houses," a hundred years from now. 

>>Now, just because a tiny percentage of the country might have rain that
>>lasts two weeks, solar electrical generation is infeasible everywhere? 
>>I think your implications require re-examination.

It's nice to see the word "electrical" above.

>As usual, you ignore probability and reliability simply because it runs 
>counter to your beliefs.

Versus just talking about them? :-)

Nick

---

From: [email-masked] (Will Stewart )
Date: 22 Sep 1995 11:11:12 GMT

In <[email-masked]> [email-masked] (Stephen Lajoie) writes: 
>
>I haven't seen ONE credible response to my post about the cost or the 
>size of solar collectors needed to provide a significant amount of
>power to the U.S. energy grid. 

You have built a strawman thesis that attempts to prove that solar
energy is worthless or 'snake oil'.  There have been many here who have
provided details of actual residential usage of solar power and heat. 
You continue to ignore this, and espouse only one approach in your
strawman.

>What's more, certain solar advocates have not provided any sort of
>numbers or data, and simply say that I've been "discredited" in my ROM
>analysis via their flippant remarks and silly statements. 

And they are true.  Have you visited the referenced data sites?  If
not, I will repeat some of them for those who may have missed them;

http://www.nrel.gov/1/information/nrel/solar/
http://solstice.crest.org/renewables/solrad/index.html

>There is really no reason for me to continue. There is no discussion.

I notice this is posted to a.e.r only, which is just as well for the
folks at s.e.

Cheers,

Will Stewart