Friday, February 26, 2010

UAZ Students Help Local Businesses to Reduce Energy and Water Consumption

I thought this was a great program to
get students involved with renewable energy and also help local businesses with
energy and water costs. 

Students from the UAZ Free Enterprise team identified two local Tucson businesses in need of some help on energy and water use, and then worked out and implemented a program to help the businesses reduce energy use, water use, and carbon emissions.


Here are the details on what the team
did -- there is contact information at the end if you want information on
starting a similar program ...

I have to brag a little here and mention that my granddaughter Kelly was one of the team members :)


Monday, February 22, 2010

Making, Buying, Designing, Evaluating Fins for Solar Collectors

Many of the homemade
collectors shown on this site use aluminum fins to collect the incoming
solar heat and transfer it to a tube that carries the heat transfer

The fins need to transfer heat efficiently, and need to have a good thermal connection with the tube carrying the heat transfer fluid. 

Copper tube with heat absorbing fin being installed.

This article goes over several fin designs, several ways of making the fins, some of the types of fins you can buy and where to get them. 

The new article also provides calculated fin efficiencies for some of the homemade and commercial designs.  I'm sure you are dying to know Which fins do best?  Does steel work as a fin material?  Are those big, thick, extruded fins worth the extra money? ...

All the details on fin design, fabrication, purchase, and performance here...

Some fin designs that people have sent in...

Kevin's two layer fin

Matt's bicycle powered fin former.

Tom's most impressive fin press

Got any ideas on fin design or fabrication?

Update March 11 -- I've added a couple more entries that have been turned in since this blog entry was written -- all on this page:

All the details on fin design, fabrication, purchase, and performance here...


Saturday, February 20, 2010

Bob's Solar Ice Fishing Shack

This is a really simple but very effective solar heating collector that Bob uses to heat his ice fishing shack.

The collector uses the whole south wall of the shack.

The collector is a very simple thermosyphon air heating collector that uses 2 layers of black insect screen as the flow through absorber, and 6 mil poly film as the glazing.

Bob took the time to insulate and seal up the ice shack before installing the collector, which is key to making it work.   On a sunny day, it heats the inside of the shack up to very comfortable temperatures.

All the details from Bob...

If Bob can heat his ice shack with solar, you can surely heat your home, or chicken coop, or barn, ... with solar!


Thursday, February 18, 2010

Zero Energy Homes for the Rest of Us

While visiting St George Utah recently, we found that we were in
town during the parade of homes, so we looked at a few of them.  One of the
display homes was a very efficient home built by Sun-Savvy Inc.  I was very
impressed by this home and the other homes they offer.


Their design combines a very good and very tight thermal envelope, heat
recovery ventilation, passive solar, solar thermal and PV arrays, and efficient
mini-split heat pumps to make a home that should be able to achieve net zero
energy use in the southern Utah climate.  The display home has a LEED
Platinum rating. 

Even more impressive to me is that these are very nice and very "normal"
looking homes.  These homes appear to be very easy for the homeowner to live with. 
While the energy efficiency does add some cost, the homes appear to be cost
competitive with ordinary construction homes.  In other words, these are
net zero or near net zero energy homes which should have a very wide appeal to
ordinary home buyers -- you don't have to be an eco-freak (like me) to like
these homes. 

We took the full tour, got a lot of pictures -- all the details here...

Much more on solar homes here...

Clerestory windows -- great daylighting.  These open automatically when a set temperature is exceeded.

The energy recovery ventilation unit -- an earthtube is used to precondition the intake air to the ventilator.

It seems like a lot of the "net zero" energy homes you see are a long ways
out of the mainstream -- they tend to be architecturally unique (some would say
strange) and come with an acre of PV panels that would add $100K+ to the cost of
the house were it not for some very very generous (and perhaps questionable)
rebate programs.  I don't see this type of near zero energy home ever
catching on and becoming widespread.  On the other hand, a design like the
Sun-Savvy homes seems like it could have very wide appeal.  I hope it turns into a trend.


Thursday, February 11, 2010

Solar Articles from the Fine Homebuilding Magazine Archives

I've been going through the newly available DVD archive of all of the past issues of Fine Homebuilding Magazine.  Fine Homebuilding has been published since the late 70's and has carried some very good articles on solar and energy efficient home construction.  I've added links to my picks of the best articles dealing with energy -- these are listed in New Content on the Build-It-Solar home page, and in the list below.


Here are the articles I liked the most from 1995 up to the end of 2009:

Six Proven Ways to Build Energy
Smart Walls
Bruce Coldham, Fine Homebuilding,
Dec 2009

Spray Foam -- What Do You Really
Bob Yagid, Fine Homebuilding, June 2009

Power House
Bill Heigis, Hobie Guion
Fine Homebuilding issue 203, summer 2009

Design a Home That Keeps You Cool,
William Hoffman, Fine Homebuilding August 2004

Attic Access
Mike Guertin, Fine Homebuilding, July 2002 issue 148

Rainwater Collection Systems,
Peter Pfeiffer, Fine Homebuilding, Nov 2001 issue 142

Thick Walls and a Great Room,
Jan Wisniewski, Fine Homebuilding, summer 2000 issue 131

Concrete Forms
Andy Engel, Fine Homebuilding, issue 128

Off the Grid
in Tucson
Gale Prososki-Marsland,
Fine Homebuilding, June 1997

Building a
Straw-Bale House
Janet Johnston and John Swearingen,
Fine Homebuilding, June 1996 - issue 103

You can get access to back issues of Fine Homebuilding in several ways...
the simplest way to get access to the articles is to do a one month
online subscription -- this is inexpensive, and should gain access to
most past articles.
I'll go through the 70's to 90's as time allows.

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