Subject: Re: solar house information

From: [email-masked] (Nick Pine)
Date: 28 Feb 1995 04:15:13 -0500

Jason M. Roth <[email-masked]> wrote:
>...here are the 4 basic solar systems:
 
>DG, Direct gain, which means sun-facing glass into the living space with
>thermal storage inside. Simplest and cheapest, but...

A poor performer, often reducing the backup heat for a house by less
than 30%, or even  increasing  the backup heat requirement in very
cloudy areas. Movable insulation helps, but you still have to live
inside the heat battery...

>AG, Attached greenhouse...

A low-thermal-mass sunspace, NOT a greenhouse full of plants, containing
thermal mass, is a better performer, by as much as a factor of three.

>TW, Trombe wall, a system developed by a Frenchman in which a thick
>concrete wall is placed on the sun-side with glass on the outside.

Another poor performer, compared to a low-thermal-mass air heater on
an insulated south wall. I put Trombe walls on my house 20 years ago,
when I didn't know any better.

>WW, Water wall, in which water-filled prisms (oil drums, plexiglass
>cylinders, etc) are just inside the sun-glass and act as thermal mass.

Again bad, in cloudy areas. If the water is just inside the glass, the heat
will leak out through the glass all night and during cloudy day periods.

>H2O is _the_ best storage mass (in efficiency, at any rate.

Agreed. Water is also cheap, and it can be easily moved around.

>Another option is less direct, in which you run pipes through solar
>panels and use that water to heat the house (radiant or baseboard or
>whatever);

Very expensive, and those panels up on the roof have lots of thermal
losses, which do nothing to heat the house, compared to a water heater
in the sunspace. And they may freeze, or heat up to 400 degrees if the
pump fails, ie during collector stagnation, which may break the glass covers.
It is better to have a solar closet as a deliberately stagnant collector,
IMHO.

>another includes a rockbed, in which heat is gathered and stored in a
>rockbed near the house, and the heated air is circulated up to the house
>(thermosiphoning).

How about putting the rockbed INSIDE the house, in an insulated
closet, on the first floor, and using thermosyphoning to heat it from
an air heater in the sunspace in front of it, and using 55 gallon
drums full of water instead of rocks. Drums are free, and last at least
20 years, and they are easy to stack up. Water has three times more
thermal mass than rocks, and the air spaces are bigger, so natural
convection or a small high-temp fan (eg Grainger's 4C861) works better
to heat these "rocks."

>That's a brief summary; just about any solar book will cover these.

I guess we need a new book. Perhaps John Allred will write one...

Nick

From [email-masked] Mar  7 11:31:31 1995
Date: 3 Mar 1995 12:39:35 -0500
From: Nick Pine <[email-masked]>
Subject: Re: Nick's lecture

Hi boB :-)

>I would be interested in finding out more about your lecture and designs, 
>I don't suppose that you'll be in the Melbourne FL area at all?

I might get down that way some time. Would you like me to lecture there?
I've only been to Florida a couple of times, once for a business meeting
in a posh Naples hotel (nice sailing :-) and once to visit my aunt in
Homestead, who has since moved closer to Miami. If you paid me to come,
I'd be a lot more likely to show up :-)

>Would it be possible to get copies of your lecture and slides?

Maybe. Most of my lecture is comments on slides of local buildings,
with green film pen markings on the back of each slide to show how they
might be improved with solar and insulation retrofits, and comments
about the costs of materials and numerical estimates of the amount of
energy each retrofit would save. I hand out a few copies of postings,
and tape a few large architectural drawings of my designs on the wall,
and I bring along 3 empty 55 gallon drums, a K-mart radiant kerosene
heater used as an infra-red solar simulator and 3 linear parabolic
reflectors made of Thermo-Ply, foil-faced foam and 3M SA-85 solar
reflective film, to aim at the simulator to make a sort of infra-red
whispering gallery, boiling water in a coke bottle at the focus, a
high temp fan and speed control, a bimetallic-coil-spring-operated
automatic foundation vent and a hair dryer to make it work, after I
adjust it for a higher temp range, 200 ft^2 of shadecloth, 140 slides,
12 viewgraphs, 50 lbs of books, some 1 x 3s, large pieces of Thermo-Ply,
various kinds of thermometers and light meters, a laser level, some 12'
pieces of Dynaglas, etc., etc. So this is not a very portable show,
as I have done it so far. I'll be doing a small and different version
again in Dallas, TX next week, at the Monolithic Dome convention, 
and then at 3 or 4 local schools and universities soon after that...

Nick

---

From: "Jason M. Roth" <[email-masked]>
Date: Mon, 27 Feb 1995 13:44:46 -0500

>[email-masked] ([email-masked]) wrote:
>: For my son's school project, he must design and build a model of 
>: a solar heated house. Can anyone suggest a source of information 
>: or plans?
> 
>Check the local library for anything by Malcolm Wells, if you want the
>underground option. Basically you want most of the glass facing the
>equator, perhaps a greenhouse on the south wall. You need mass to store
>the energy, such as a thick stone or concrete wall, or water tanks, or
>Glauber's salt. The heat will be radiated back into the house at night.
>You want earth berms and coniferous trees on the north side to shelter
>from the winter wind. You could also put solar water heating and 
>photovoltaic panels on the south side of the roof. The floor plan could
>be similar to a high-rise apartment with all the windows on one side.
>Brian Calvert ([email-masked])

Of course it's nice to see someone else recommending Mac, but at least
one point: there's no need for all the windows to be on one side;
indeed, the non-sun side will give the clearest, glare-free views, not
to mention cross-ventilation. To go one more step, here are the 4 basic
solar systems:

DG, Direct gain, which means sun-facing glass into the living space with
thermal storage inside. Simplest and cheapest, but relatively difficult
to control and requiring detailed design.

AG, Attached greenhouse, which means  a sun-facing, glassed-in space
adjacent to the living space; this does a number of things, inc.
improving (reducing) infiltration, allowing control (usually vents into
living spaces), providing a greenhouse, and giving privacy.

TW, Trombe wall, a system developed by a Frenchman in which a thick
concret wall is placed on the sun-side with glass on the outside. The
wall gets hot, the air between the wall and the glass gets super-hot
(150+), and vents exist top and bottom to allow air to circulate.
Super-efficient, traditional-looking from the inside, a bit goofy on the
outside.

WW, Water wall, in which water-filled prisms (oil drums, plexiglass
cylinders, etc) are just inside the sun-glass and act as thermal mass.
Kind of weird, but H2O is _the_ best storage mass (in efficiency, at any
rate).

Another option is less direct, in which you run pipes through solar
panels and use that water to heat the house (radiant or baseboard or
whatever); another includes a rockbed, in which heat is gathered and
stored in a rockbed near the house, and the heated air is circulated up
to the house (thermosiphoning).

That's a brief summary; just about any solar book will cover these.
ASHRAE puts out publications that can tell you how much of each system
you need to make up a given # of BTUs in a given climate. Good luck
JMR

93 SL2, blue-green

"His learning is too often borrowed, and his opinions are too often his own."

"My complete autobiography:
In 1964, after 10 years spent spreading corporate asphalt on
America in the name of architecture, I woke up one day to the
fact that the earth's surface was made for living plants,
not industrial plants. I've been an underground architect
ever since. I live on Cape Cod, and I'm writing this in the dry,
sunny silence of the Underground Art Gallery."
-- Malcolm Wells, who is the nicest guy I've ever met.