Subject: Controlling the solar scourge

From: [email-masked] (Nick Pine)
Date: 1 Oct 1995 09:01:38 -0400

From Steve Baer's 1979 book, _Sunspots_:

  Solar Insecticide

  Money attracts university and industry experts. I am suspicious of such
  experts. After listening to a meeting for three days, I think I understand
  the mechanics of the government's grants for work on solar energy.

  When people want to get rid of a kind of insect, one method is to not
  directly kill the insect, but to raise and relese vast quantities of sterile
  male insects. The sterile insects make up the major portion of the male
  insect population and thus, after mating, most females are infertile.
  After a few generations the insect population is down to a handful.
  I see the projects and research teams chosen by the government as sterile.

  When someone is interested in solar energy he is likely to bump into
  publicity or people associated with such projects. Result: he is advised
  that solar heating, cooling, or power are "not feasible at this time."
  I can't find any one person who has planned this solar insecticide scheme;
  I do not think he exists. Rather, these techniques seem to naturally grow
  out of an unspoken understanding that oil, coal, gas and nuclear power
  are the proper energy sources. If the sun is so good, why doesn't it belong
  to GE, GM, ITT or the NRC?

  Solar Vaccination

  Another way to look at the money now spent on solar energy research
  is that it is being used as a vaccination against the full blown disease
  of solar energy utilization. A certain amount of solar energy activity
  is encouraged so that the country can reach an actively immune state.
  Those who own or control the competing energy sources--coal, oil, gas,
  nuclear--can then become familiar with the threat--solar energy. Projects
  can be undertaken that will result in failure or extraordinarily high
  prices. Reports--stacks of them--will indicate hopeless bottlenecks and
  contradictions in the design and manufacture of solar heating equipment. 

  I would expect many of the projects to be undertaken in the midst of
  huge government laboratories primarily devoted to other activities,
  such as nuclear energy. There the avid solar energy worker is likely
  to find himself transferred when he becomes too productive.

  It is certainly fortunate that a great deal of success is within reach
  of the backyard inventor and the small shop.

Nick

---

From: [email-masked] (Nick Pine)
Date: 3 Oct 1995 05:20:30 -0400

Tom Gray  <[email-masked]> wrote:
>Nick Pine writes:
>>Steve Baer writes:
>>>   prices.
>Interesting theory, but it fails to explain why many of the most 
>ardent critics of solar R&D are conservative supporters of the fossil 
>and nuclear energy industries.

That seems natural to me. If you are against one thing, you tend to be
for an alternative. This is an old amorphous theory of Steve Baer's,
not mine. Perhaps you are talking about different, less subtle people (?)
Steve thought this was not an organized conspiracy, just what happens
when people chase money...  

On the other hand I can imagine some people at the Electric Power Research
Institute or Exxon might have sat down 20 years ago and said "Let's do a
study to debunk this solar thing," and gotten some people to come up with
the conclusions they had in mind at the beginning. To a certain extent,
they don't have to do that any more, because there are a lot of uneconomical 
or poorly-performing AE systems around now to look at. For instance, everyone
"knows" that passive solar houses are an expensive hobby, and they don't work
very well except in the Southwest US. And then there's my friend in New York
City who plans to cover his house with PV panels and fill it with batteries,
and Dennis Weaver's two million dollar collection of old tires. 

Even without this help, it seems to me that large existing infrastructures
and flows of money will do what they can to protect themselves, somehow,
against the widespread practical use of alternate energy.

>It also fails to explain why the government continues to fund fossil 
>and nuclear R&D.  Is this also a vaccination?  If so, why hasn't it worked?

I guess that's just pork barrel power: "Hey, we have jobs, we vote, we
want some of that money too." :-)

>But they aren't.  Federal renewable energy R&D is largely focused at 
>the National Renewable Energy Laboratory.  For further information, 
>visit their WWW site at <http://nrelinfo.nrel.gov>.

I visited NREL last month. It's changing. For instance, they are acquiring 
some combustion engineers. Their projects seem strangely impractical to me.
They seem more interested in high tech research than proliferation of high-
performance, cost-effective systems. Their solar data book and solar data
CDs are very nice, but their shiny new visitor's center has a Trombe wall,
invented in 1881...

A few years ago, I spent some time explaining to a local architect, a more
technical person than most, who had studied some engineering, that a "Trombe
wall" with some insulation on the outside and some passive plastic film
dampers to the inside of the house, that let air flow into the house during
the day, was probably a lot more efficient at collecting and keeping solar
heat in the house than a plain old "traditional" Trombe wall, with bare
masonry right behind the glass, with no insulation. Here's what I said:

  A "Trombe wall" with insulation on the outside, and 1 square foot of South-
  facing single-glazed area and an R-value of 20, will receive about 1000
  Btu/day of heat on an average 32F December day, where I live. If the room
  behind it has a constant temp of 70F, and the sun shines 6 hours a day,
  on the average, the energy that leaks out of the glass will be about 6 hours
  x (70F-32F) x 1 ft^2/R1 = 228 Btu during the day, and 18 hours x (70-32) x
  1 ft^2/R20 = 34 Btu at night, a net gain of 1000 -228 -34 = 738 Btu/day.
  Simple, no? (750 Btu, net, with double glazing, which passes less sun.)

  A standard unvented Trombe wall (Table IV-14b of Mazria's book says vented
  ones don't work much better) with a very large uninsulated thermal mass
  right behind the glass and an R-value of, say 2 (roughly 1' of masonry),
  would have an average temperature at the outside wall surface of about
  32F + R1 x (70F-32F)/(R2+R1) = 45F, if there were no sun. If you add a
  heatflow of 1000 Btu/day of sun to that model, falling on the outside
  of the wall, the outside wall surface will have an average temperature
  of about 45F + 1000/24 x (R=2/3) = 72.4F, which contributes 24 hours x
  (72.4F- 70F) x 1 ft^2/R2 = 29 Btu/day to the room behind the wall.

  So the "improved Trombe wall" above, (actually an air heater with the
  thermal storage inside the house) is more than 25 times as efficient
  (738/29) at collecting and keeping heat in the room behind it, than
  the usual Trombe wall. This is somewhat oversimplified, of course...

And do you know what the architect said? "I agree with you completely, but
if you do that, you will violate the integrity of the traditional Trombe wall,
which has a magical, wonderful way of *flywheeling*, and transporting the
heat through the wall, so it is available at the other side *precisely* when
it is needed, the next morning!" And he went on and on about this conceptual
delight, this conceit, completely ignoring numerical performance... :-)

Trombe walls are also thermal disasters during long strings of cloudy days.
When the sun goes in for a week or two, they lose their stored heat in less
than a day, and then leak house heat badly, dramatically raising backup
heat or other solar thermal storage requirements.

I'm still amazed that so many people, even in these newgroups, are still so
interested in Trombe walls, or their passive solar equivalents, like
high-thermal mass sunspaces. A lot of people are apparently still willing
to settle for high-cost, low-performance passive solar house heating
techniques, with 30% yearly savings in backup space heating costs over a
20 year payback period, compared to a conventional house, vs. houses with
warmstores, solar closets, sunspaces and transparent siding, which can
provide close to 100% of the space heating energy needed for the house AND
close to 100% of the hot water, with a 2 year payback period.

>Maybe for PVs (although I doubt it)

I do too. Seems like you need a million dollar semiconductor fabrication
facility to do interesting things with PVs. And even then, the PV products
will still be expensive. Of course the big price breakthroughs are just
around the corner :-) 

>not for wind. 

I'm not sure about that. If we had more wind in PA, I might be trying to do
some aerodynamic simulations on my PC, along the lines of the Polytech school
in Montreal, and doing VAWT experiments in my backyard, with an auto rear end
sitting under a double delta Darrieus configuration made with plastic coated
steel tubing, steel wires and dacron sailcloth. 

>For utility-scale wind,

I'm thinking more about 1-10 kW, or perhaps less power.
No tower. Matters of scale and centralization are important.

>the cost of bringing a new design to market is $millions, even in
>the private sector.

I believe that.

>For residential wind, systems are still too pricey for mass market success.

I like the Air 303. $550 for 375 watts, from Jade Mountain at (800) 442-1972.
Now all we need is a cheap, reliable synchronous inverter to feed this tiny
power back to the grid. I'm an electrical engineer. I keep telling people
that a synchronous inverter at this power level should not cost much more
than a lamp dimmer. A simple triac bridge, a backwards lamp dimmer, with a
small microprocessor to determine the optimum load for the windmill, $10
worth of parts. Someday, someone will design one of these. This is not a
very difficult job for the right kind of electrical engineer. Perhaps there
is a German product like this already. 

>Bringing their costs down through advanced
>manufacturing technologies is, again, a high-stakes game. 

I think the Air 303 people are investing lately in molds to bring down
the price even more. This is pretty straightforward, not a very risky game,
and the stakes are not all that high, compared to the sales figures. It
seems very unlikely that NREL would ever do something like this. 

Nick

---

From: [email-masked] (Nick Pine)
Date: 4 Oct 1995 06:10:20 -0400

Harry H Conover <[email-masked]> wrote:
>Clark Dorman <[email-masked]> wrote:
>
>>>I like the Air 303. $550 for 375 watts, from Jade Mountain at (800) 442-1972
>>>worth of parts. 
>I suspect you're missing a few vital pieces.

People have often suspected that :-)

>First, you're going to need an inverter transformer with some efficiency
>(magnetic components don't come cheap).  At 375W power level, this shouldn't
>cost more than $40 or so.

Hmmm. What would I do with that? I'd use a choke in series with the triac
bridge. I have one somewhere up in my attic, made for this purpose, about
10' of 16 ga magnet wire wound on a toroid made of galvanized iron pipe, with
an air gap. The wire is undersized for this 4 kW version and the toroid is
bigger than needed, to keep the wire cooler. A 375 watt version might use
a bent nail for a core. Next?

>Next, you'll need a quantity of Leg switching transistors (6-12 
>should do nicely) so you'll end up with a  waveform somewhat 
>approximating a sine wave.

Why does this remind me of my Kentucky cousin, Ophelia Legg? I'd just a 3 Amp
triac bridge, like a backwards lamp dimmer. Switching frequency 60 Hz. When
the DC output of the windmill is larger than the grid voltage, you turn on
a triac (this would work best with a high DC voltage.) When the grid voltage
becomes larger than the DC supply voltage, the triac turns itself off. I
posted a schematic of this circuit months ago here, with waveforms. 

>After that, a good harmonic filter, at this wattage, probably between $30-50.

That's what the choke's for, to make less than 5% rms voltage distortion
at the grid interface. It also provides current limiting. 

>Combine this with phase/frequency locking

Huh? I think this thing would be called "line commutated."

>and fail-safe "outage" detection (another $20)

I see :-)

>and you'll pretty much cover the OEM bill of materials.

Which is of course what  I  was talking about.

>Now, add in the cost of manufacturing, engineering, advertising, marketing, 
>distributor mark-up and profit, and you'll likely end up with a selling
>price that's about 3-4 times material cost.

The usual ratio is 4-6 times the cost of the parts, to pay for the
salespersons lunches and BMWs.  

>You can save a few bucks by deleting the lamp dimmer components, since
>its components provide no useful function here.

I'm not sure that you understand how this thing would work, Harry.

>What kind of engineer did you say you were?   :-)

I travel with custard pies.

Nick

---

From: [email-masked] (Nick Pine)
Date: 3 Oct 1995 14:53:56 -0400

Clark Dorman <[email-masked]> wrote:
 
>[email-masked] (Nick Pine) writes:

>This does not seem to make economic sense.

Better than grid-connected PVs... Much better than filling your house
up with batteries and inverters, if you live near a grid.

>Even assuming that you get 375 watts _all_ the time, then the payback is
>several years.

Not bad...

>You would produce .375 kwh per hour and at $.05 per kwh, it would take you
>29333 hours (3.3 years) to make back the $550.  With down time and realistic
>assumptions, it will be well over 5 years.

Sounds pretty good to me. BTW, my electricity costs about 12 cents/kWh,
and that cost increases with time. I use an average of 600 watts. Steve
Baer uses closer to 60. He would become a net power producer, with one
of these 45" toys on the roof.
 
>Also, connecting power back to the grid is just not that simple.  If nothing
>else, the power company needs to be able to switch the power coming from you
>on and off so they can work on the lines.

Not if your machine can do that itself. It can be just that simple :-)

>And if you want to be paid for your investment, it needs to be meters
>differently.  

False. For instance, in Vermont (I think) state law requires that the
utility let you run a single meter in both directions. And this is
consistent with net billing, and technically, it works fine.

Nick

---

From: [email-masked] (Nick Pine)
Date: 6 Oct 1995 07:24:49 -0400

Nick Pine <[email-masked]> wrote:

.I like the Air 303. $550 for 375 watts, from Jade Mountain at (800) 442-1972.
.Now all we need is a cheap, reliable synchronous inverter to feed this tiny
.power back to the grid. I'm an electrical engineer. I keep telling people
.that a synchronous inverter at this power level should not cost much more
.than a lamp dimmer. A simple triac bridge, a backwards lamp dimmer, with a
.small microprocessor to determine the optimum load for the windmill, $10
.worth of parts. Someday, someone will design one of these. This is not a
.very difficult job for the right kind of electrical engineer. Perhaps there
.is a German product like this already. 

An email friend from the Netherlands replies:

.I know that Siemens designed a PV-module with an integrated inverter that 
.you can just plug in the socket. Also at the Renewable Energy business unit
.of the Dutch National Energy Research Center ECN a 100 W inverter has been
.developed for small scale grid connected applications. So, these things do
.exist! If you are really interested, just try to get in contact with these
.guys.

Voila. Now will someone please design a nice 110V version?

Nick

---

From: [email-masked] (Nick Pine)
Date: 9 Oct 1995 08:23:05 -0400

>>.you can just plug in the socket.

>>Voila. Now will someone please design a nice 110V version?
 
BTW, something like this was apparently used in Australia, a
Siemens/Butler joint venture. Does anyone know anything about that?

>If I produce solar power enough to cover my own comsumption and even
>leave extra, will my electric meter run backwards when the extra
>electricity is oozing out of my house wiring? 

Yes, unless the utility has done somethihng to prevent that, eg
installed a mechanical one-way ratchet, so the wheel inside can only
spin in one direction (even electronic meters will run backwards, if
not disabled--these usually have wheels inside too, to make it easy to
check the calibration.)  
 
You would want to electricity to ooze out in the grid direction BTW,
not all over the house. This usually happens quite naturally. 

>If yes, wouldn't I soon be facing monstrous bills from the electric
>company, as if my meter reading is lower than 2 months ago, they will
>surely assume that the meter shows my monstrous consumption!?

One hopes they would make the right choice, if your electric meter
reading should change from say, 50,000 kWh to 49,500 kWh, between
believing that in the last month you opened a major aluminum plant,
consuming 99,500 kWh, ie a continuous monthly electrical consumption
of 138 kW, eg 630 Amps at 220 Volts, or believing your story that you
sold them back a bit of electrical power. Then again, you might want
to install your own ratchet, to avoid confusing them, and just donate
the extra power to them, in exchange for their cooperation and benevolence.

Nick