[Greenbuilding] Subject: Re: Trying to maximize passive...

[David Delaney]

At 06:41 AM 22/04/2007, Nick Pine wrote:

>David Delaney writes:
>
>> ... I think you will be very lucky if you don't
>> see the cost of home heating in New Brunswick (and
>> everywhere else) double several times in the next 10 years.
>
>Wow. I've been thinking we'll see a lot more alternatives
>if oil stays up at $60/barrel, eg tar sands and coal-to-oil
>conversion, as well as more houses that heat and cool
>themselves naturally. Sasol is building 2 coal-to-oil plants
>in China, with Shell as a partner. They say they can make
>money (and lots of CO2) if oil stays above $24/barrel.

It seems likely to be impossible to ramp up these and other 
alternatives at the rate of decline of oil and NG production 
that now seem more than plausible within 10-15 years, _and_ 
to provide additional growing energy production to maintain 
economic growth and enriching populations. Google ASPO oil. 
Google Chris Skrebowski oil Google Matthew Simmons oil, 
especially google Matthew Simmons natural gas.  Houses that 
heat and cool themselves are a _very_ good investment.

>> Indirect gain permits higher solar fractions than direct
>> gain. Here's an example:  You can ease the direct gain
>> mass-glass trade-off, and get a higher solar fraction by
>> having a low-thermal-mass sunspace on your south wall which
>> you don't mind letting get very hot or very cold.
>
>An ideal sunspace might be filled with 70 F house air when
>the sun is shining, with 70 F air between dark mesh curtains
>and the cold glazing to minimize heat loss to the outdoors.
>Air might slowly pass through the curtains from south to north
>and warm and rise to the ceiling. People might be comfortable
>in normal clothing in slow-moving air and only 20% of full sun.

Good idea.  Still, at some point there will be too much energy
in the sun space unless you have an isolated heat store or you
over ventilate the sun space and/or the house.

David