1 Year Report on Gordon's Deep Energy Retrofit

A few months ago, Gordon and Sue sent in a very complete description of their project to completely remodel a poorly insulated and drafty schoolhouse for their residence.  There goal was to bring it up close to Passive House Institute standards.  Through a combination of an external Larsen Frame insulation scheme, added sun space, much sealing, excellent windows, and passive solar gain additions, they have achieved their goal.

The new sunspace added as part of the retrofit.


Gordon sent in the report after one year.  It covers performance to date (very good), and some fixes they have made to some problems that have come to light while living in the new home.

The very detailed report on the original project, including report, many pictures, and thermal analysis spreadsheet...

The 1 year update report, including performance to date, problem fixing, and updated thermal analysis spreadsheet...

This is the most carefully planned and executed energy retrofit I have seen, and it's really nice to see it living up to expectations.

Gary

Storage Tank Kit for DIYers & DIY Solar Kits In General

The Softank is a kit for a 200 gallon water tank for heat storage.  The kit includes the parts that would be somewhat difficult for a DIYer to find or fabricate like the liner and the outer structural support cylinder.  The person building the tank buys the insulation locally, supplies some labor, and saves some money.

Details here...


Note: Heat exchanger not included with tank kit.

I like the Softank kit, but what I like even more is the idea that kits like this could be offered to home owners who want to build solar water or space heating systems.  These kits could bring building such a system to people with modest DIY skills, and also increase the likelihood of a successful build.  

Kits of this kind could include the difficult to obtain and difficult to make parts, while allowing the DIYer to buy readily available parts locally.  This approach avoids shipping large and fragile finished items like collectors, and would save the hassles, expense and CO2 emissions associated with truck shipping finished items.

Well designed kits and good instructions could greatly increase the chances of building a successful system -- even for not so experienced DIYers.

With commercial solar water heating systems selling for north of $8000, there is plenty of room for kit makers to earn a good profit and also save home owners lots of money.  A great opportunity for some new businesses!  How about it entrepreneurs?


Gary

THREE new Owner Built Solar Space Heating Systems

This has been a good week for new solar space heating systems sent in to Build-It-Solar!
Thanks very much to the Eric, Al, and Tom for describing there well designed and built systems. 
These are all large collector systems that can do significant solar heating -- lots to learn from the detailed descriptions of these systems.

The 1st is Eric's space heating and hot tub heating system that uses 300 sqft of water heating solar collectors, and has both a solar and boiler heat source.

The 2nd is Al's space heating collector that is primarily a solar air heating collector, but also has a smaller water heating capability integrated in the same collector.

The 3rd is Tom's new 330 sqft solar space heating system.  This system uses Tom's 3rd generation design for the copper tube, aluminum fin collectors.  This installment covers the design, build and install for the collectors.  The next will cover heat storage, plumbing, and controls.

See below for summaries, and the links for very detailed descriptions.

Al's Hybrid Air and Water Heating Collector
This is a very nicely done collector of about 100 sqft.  It is a space heating collector that primarily heats air that is circulated directly into the house.  But, it also has a smaller water heating capability that is used to store some heat for use during the night.


Its a nice looking collector that is well integrated with the house.

Since the collector area is about 15% of the house floor area, the collector will often generate more heat that can be immediately used on a sunny day, so it makes sense to add the limited water heating capability to store some heat for use later in the evening.

All the design and construction details from Al here...

Eric's Space Heating, Water Heating, Hot Tub Heating Solar System

This is a very nicely designed and built system from Eric -- a fellow Bozeman resident.
The system uses about 320 sqft of commercially made water heating collectors as its main heat source.  The collected solar heat is used for 1) space heating, 2) domestic water heating, and 3) hot tub heating.  The system also integrates a boiler as the secondary heat source.  



This is a pretty complicated system in that it heats floor space, a hot tub, and domestic water, and includes both a solar and boiler heat source into the same system. 
This is a difficult set of things to do, but Eric pulls it off with a pretty simple system.  Maybe the fact that he is in the HVAC business and specializes in solar system helps :)

All the details on Eric's system...

Tom's Large Solar Space Heating System
Tom's new space heating system uses 330 sqft of the aluminum fin/copper tube collector design.  This is about Tom's 3rd generation build of this type of collector, and he has a very refined design.   The collectors are mounted in a good looking common housing, and glazed with twinwall polycarbonate glazing.  Performance should be very good.



All the details on Tom's System...

Much more on Solar Space Heating Systems...

Gary

Two Good Rainwater Harvesting Tank Ideas

Here are a couple nice ideas for tanks for rain water harvesting -- they are kind of at opposite extremes, but both well designed, interesting, and different than the usual rain water harvesting tanks you see.

The WooTank Two
This is a very nice tank design from Nathan.  The tank has an natural looking external frame made from 2 by lumber -- it looks great and would fit in very well with most landscaping schemes.  While Nathan painted his, you could stain it.  Nathan actually uses the tank as a large fish tank, but I think it would also work well for rain water catchment.  A tank like this can also be used as thermal mass to regulate and store heat from a greenhouse/sunspace, as Nathan shows in this earlier article... (pdf)



The tank walls are plywood.  The bottom is formed by concrete backer board that sits right on a thin layer of gravel over undisturbed dirt.  The tank liner is a single piece, EPDM rubber.  I think that this design is durable, efficient, inexpensive to build, and looks really good in the landscape.  All the details on the WooTank . 

Thanks very much to Nathan for writing this up and sending it in!




The FatBoy Water Wall Tank
This is another interesting rain harvesting tank.  If you are looking for something different than the usual cylindrical poly tanks, this might be for you.  They have a interesting , sculpted look.  Its a commercially available tank, and there are said to be several thousand installed.

Each tank holds 650 gallons and several can be stacked together.  I suppose they could even be used inside the house for thermal mass -- as in a thermal mass water wall...




Much more information on water conservation, rain water harvesting, grey water reuse,...


Gary

Our New Grid-Tied PV System -- First Sun

The new PV system we have been working on putting in is up and running.  There are many pages of detail and a hundred or so pictures that go through the whole planning, design and installation process in mind numbing detail here...
Sections on performance and economics of the system are also included.




The system is a 2150 watt grid-tied system.  It uses the new micro-inverter approach from Enpahse -- so, each PV panel gets its own small grid-tie inverter.

The panels are ground mounted with our own mounting racks. 

We did the whole installation ourselves, and I've tried to include enough detail to be helpful to anyone who wants to install a PV system of their own.  I've tried to cover not only the details of the component installs and wiring, but also the stuff like deciding on what kind of system, locating the panels, doing a solar site survey, and going through the permiting and net metering process.  It should be enough reading to put you to sleep for a week of nights.



It was a technically interesting and fun project -- not having any previous experience with solar electric stuff, I learned a lot. 
But, the economics are also interesting.  Basically, the system cost was right near $10K or $4.65 a watt -- after rebates this gets down to $6.5K and $3 per watt.  Better than what I was expecting.  The $ saving per year if you pay 10cents a KWH would be $300, or about a 5% return on the $6,500 -- tax free and energy price inflation protected.
Not so bad, but when you compare our PV to well thought out conservation/efficiency projects, or to DIY solar heating projects its comes out a very very distant 2nd -- some examples in the Economics section.

I've fallen behind in getting other projects that people have sent in up, but now that the PV is done, I plan to catch up right after Thanksgiving -- so, keep the projects coming in!

Gary

Heat Pump Water Heaters

I added a couple new entries in the Heat Pump Water Heater Section. 

The first is a Tom Gocze video that describes installing a Geyser Heat Pump Water Heater -- a good video -- informative and funny in places.  Tom is a long time friend of Build-It-Solar and has contributed a lot of helpful information.  He does some radio and TV work in Maine, so if you are in place where you can get these, they are very good.  Tom knows renewable  energy well, and has a good, practical approach to energy matters.



Heat pumps in general remove heat from one place and "pump" (transfer) it to another place.  For the heat pump water heater, the heat is removed from the household air and transferred to the water in the water heater tank.  The efficiency of the whole process is about 200% (that is they have a Coefficient of Performance (COP) of about 2).  This compares to a regular hot water heater which has a heating efficiency of nearly 100%.  In addition, during the summer they have the added benefit that they provide some free air conditioning -- that is, they cool and dehumidify the household air some. 

The cost of the units are around $700 to $1400.  Some of them (but not all) qualify for the 30% federal tax rebate, and some states may also offer some incentives.

On the down side the cool air they provide, which is a plus in the summer becomes a negative in the winter.  In the winter the cooled air has to be heated back up by your space heating system, and this is a cost.  It seems to me that in effect it will reduce the efficincy back to about what a regular electric water heat is for the winter.  
This paper on a Building America demonstration home shows a way to hook up the heat pump water heater in such a way that in the summer, the cooling air is used to cool the kitchen area, but in the winter the ducts are switched around so that the heat pump air is taken from the crawl space and does not cool the house air (or at least not as much).  This seems like a worthwhile improvement, but does complicate the installation.

Does anyone have any ideas on a winter hookup that would not steal warm air from the house?  Seems like there ought to be a way to do this?

From a carbon emissions point of view, I get these numbers -- the
- Regular electric water heater:  1.5 lbs CO2 per KWH heat out
- Heat pump water heater: 0.75 lbs CO2 per KWH heat out (COP of 2)
- Regular NG gas (EF0.65):  0.75 lbs CO2 per KWH heat out
- Tankless NG gas water heater (EF0.85): 0.6 lbs CO2 per KWH heat out

So, they are substantially better than a straight electric water heater, about the same as a conventional gas water heater, and not quite as good as a tankless gas heater.
These numbers are based on the 1.5 lbs of CO2 per 1 KWH of electric power (the US grid average), and 0.5 lbs of CO2 per 1 KWH of heat output from NG.


Gary

New Idea for Heating Domestic Water

Energy Alternatives has come up with a new design for heating domestic water.  Their design pipes water/antifreeze through several PEX pipes that are suspended in the attic ridge roof vent. 



The water heated by the PEX tubing is passed through a heat exchanger coil in a domestic water preheat tank.  The domestic water is preheated in this tank before it goes on to the regular water heating tank.

No real data is given on performance, and I suspect that for many climates, this is a three season heater at best, but it does offer an interesting alternative to solar, and it keeps the external look of the roof unchanged.

One article suggests that the cost of a 40 ft section of the PEX ridge vent assembly might be around $300, and that a full kit including the preheat tank with heat exchanger might be about $3100.

Here are some thoughts about DIY implementation of the ridge vent design that could (I think) be done for less than $1000 -- maybe substantially less.

Thanks very much to Chris for finding this and suggesting it!

Gary

Heat from Composting Biomass

I've been collecting material on the idea of extracting heat from compost piles and adding it to this section...

At first, this was a "that's kind of interesting" idea to me, but it has become more and more of a "that might really work" sort of idea.

Basically these schemes (there are several shown) start with a carefully constructed, large pile of biomass.  The biomass heats up as it goes through the composting process.  Pipes running through the pile pick up heat which can be used for domestic water heating and/or space heating.  Some schemes simultaneously collect bio-gas, which can be used for cooking fuel or even running a vehicle or generator.


Marc's compost furnace under construction.

A lot of work was done on this in the 70's by Jean Pain in France.  The section has some good descriptions of Pain's work, including two newly added videos (thanks to Curbie for these).

Marc's compost furnace work is very interesting, and includes some results from his first winter of operation.

The MB-Soft work in this area is interesting, if a little hard to decipher.

The New Alchemy papers are also quite good.

The attraction of this approach to me is that it holds the promise of a carbon neutral way of generating useful amounts of heat over long periods of time.  Some of the Pain piles are said to have been still generating useful heat after 18 months.  It is quite a bit of work to build one of the structured compost piles and set up the heat extraction plumbing, but then you may be able to get useful heating from the pile for an entire heating season.
The efficiency is claimed to be of the same order as burning the biomass -- maybe even a little better.  In many cases, the biomass can be material that would just be left to rot in place.

Does anyone have more useful information on this area?
Any thoughts on how useful and idea this might be?

Gary

Our New PV System

I've been trying to get the new PV system in the last week or so, and as a result I'm falling behind on getting new entries up on the website.  Thought I would just give a short progress report on the PV system. 

I do plan to do a new section with a lot of detail on the whole PV system process with lots of detail on design, site survey, mount construction, wiring, installation, ...   probably a lot detail more than you ever wanted to see :)

After much looking at a lot of options, I chose the type of system that uses one Enphase micro inverter for each PV panel.   In this kind of system, each PV panel gets its own grid-tie inverter, which is mounted right at the PV panel.  Each inverter takes one PV panel's DC output and converts it to 240 VAC that is grid compatible.  Each inverter plugs into the next inverter in the array, and you end up with all the power from up to 15 PV panels being available as 240VAC at the last panel/inverter in the string of panels.  My system has 10 PV panels at 215 watts each for a nominal total of 2150 watts. 

I bought the system as a "kit" from Wholesale Solar -- this one...

The more common approach on grid-tie systems is to wire several PV panels in series so that the they produce a high DC voltage.  This string of PV panels are then wired to an single inverter which takes the several hundred volts from the string of PV panels and converts to grid compatible 240 VAC. 

There are pros and cons to each approach, but (I think) both are pretty simple systems that can be DIY projects as long as you are VERY careful to mind the safety precautions. 

In my system, the PV panels are mounted on the ground and are located about 100 ft from the house out in the weeds.  The wires are run underground from the PV panels to the area where power comes into the house, and the grid-tie is made there.


I rented a power trencher to dig the trench for the wires.  In our hard soil, this saved a lot of time and effort.

After some debate with myself, I settled on a rather robust mounting system made from 4X4 treated lumber.  I wanted something that would withstand the high winds we get occasionally, and that would last 30 years.  Treated lumber may not be the best choice for long life in some areas, but around here, if properly installed it lasts a very long time.


This shows the framework that the PV panels will be mounted on. 
Anchored in about in 3200 lbs of concrete!



Running the wire (in conduit) from the house to PV array.


I clamped the PV support rails and a PV panel in place just to get the spacings
right and to plan where the inverters would go (they mount to the same rails as the PV panels)

This is where I am -- just waiting for a day or two of descent weather to finish it up.

Gary

The Solar Decathlon

The Solar Decathlon is here!  Its going to be from October 9 to October 18.

This is a terrific event.  Here is a good description shamelessly copied from the DOE Newsletter:



v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}



Normal
0
false



false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

20 Solar Homes Take Shape on the National Mall for the Solar Decathlon

Construction is underway at the Solar Decathlon, which opens to the public on October 9. Enlarge this photo. Credit: Richard King, DOE Solar Decathlon

The assembly of 20 solar homes on the
National Mall in Washington, D.C., is rapidly approaching completion,
as the 2009 Solar Decathlon prepares to open, free to the public, on
October 9th. The Solar Decathlon is an international event in which DOE
challenges university teams to design and build homes that run entirely
on solar energy. The teams ship their partially constructed homes to
the National Mall, assemble them, and then compete in ten contests.
This year, the 20 teams came from universities in Arizona, California,
Illinois, Iowa, Kentucky, Louisiana, Massachusetts, Minnesota,
Missouri, New York, Ohio, Pennsylvania, Texas, Virginia, and Wisconsin,
as well as Puerto Rico, Canada, Germany, and Spain. Trucks rolled onto
the National Mall just after midnight on the morning of October 1, and
since then, the teams have been steadily working to assemble their
solar homes. See the DOE press release and the
Solar Decathon Web site.

This is the fourth running of the Solar Decathlon, and for the first
time, the competition features a stand-alone electrical microgrid to
which each team will have to connect their home. Starting on October 8,
each home will be monitored for its performance in five areas relating
to performance and livability: comfort (maintaining comfortable
temperature and humidity in the home), hot water (producing a
sufficient quantity at a high enough temperature), appliances (such as
keeping refrigerated items at the right temperature), home
entertainment (running a television, computer, lights, and other
devices), and net metering. For the net metering competition, homes
must use zero net energy over the course of a week, and teams receive a
bonus for producing more energy than their home consumes. Other
contests rate the teams for their communications with the public and
for the architecture, engineering, and market viability of their homes.
The overall winner will be announced on October 16. See the Solar
Decathlon's Contests and Scoring page.

DOE is the primary sponsor of the 2009 Solar Decathlon, which is
also sponsored and managed by DOE's National Renewable Energy
Laboratory. Homes will open to the public beginning on October 9, and
will be open for tours weekdays from 11 a.m. to 3 p.m., and from 10
a.m. to 5 p.m. on weekends, through October 18 (with the exception of
October 14). Not able to come to D.C.? You can keep up with the Solar
Decathlon online through daily journals posted by DOE's Richard King, the Solar Decathlon director; photos of the day from the event; YouTube videos; time-lapse photos from three cameras at the event; blogs
from the teams; the Solar Decathlon Facebook page (become a fan!); and even a Twitter feed!

Gary

First Year Performance for $1K Solar Water Heating System

The first full year of performance for the $1K Solar Water Heating system is in the books.  The graph below shows Solar Fraction by month.

All the details, and detailed plots that show collector, tank top, tank bottom, and ambient temperature are here...



So, this is the end of the promised one year of logging -- I now get my loggers back for other projects!

I've also a added a page that describes how I estimate Solar Fraction,
and considers some sources of error, and describes how my method
differs from the SRCC ratings of solar water heating systems.

Gary

Scott's 24 by 8 foot Space Heating PEX Collector

This is a really interesting solar space heating collector design.  It is built as a single unit that is 24 ft wide by 8 ft high.  Compared to building a bunch of separate collectors, the single unit construction saves some time, effort, and materials, and looks very nice.



The absorber is an extra wide variation on the PEX/aluminum absorber.

For more on the collector, including a link to Scott's site with all the construction details, and a few of my thoughts on the collector...

This is a good example of the kind of freedom to try new things and fit your design to your situation that building your own system gives.

Scott is a founder of the Yahoo SimplySolar group -- a good place to discuss your new solar ideas.

Gary

Some New Content Items for Build-It-Solar

Three New Content Items

1. Lee's Solar Mower
Some time back, Lee sent in the details for his solar lawn mower.  The article basically tells you how to convert a gasoline powered mower to a battery powered electric mower with solar charging.
One issue with doing this is finding a good electric motor.  The one that Lee originally used is no longer available.  So, Lee has found a new source of motors that should work well and are cheap and easy to find....



2. Performance Update for Marc's  Compost Furnace

Last week, Marc provided a description of his system to provide space heating via heat extracted from a compost pile.
Marc has provided some performance data and other observations based on the first full season of operation...


3. A Home Built Grid-Tied PV System with Battery Backup
A
detailed account of the design and installation of a grid-tied PV system
with battery backup.

A home built ground mount system from treated lumber
is also described.

Heat Distribution For Solar Heating Systems

I added a section on methods of heat distribution for solar heating systems.  The new section provides links to a number of ways to distribute heat to a house for a solar heating system with an emphasis on DIY approaches.

Distribution of heat for solar heating systems is complicated by the fact that solar heating systems are more efficient when producing water that is not hot by boiler standards -- that is, boilers can easily produce 160F (or more) water, while solar heating systems are going to be more efficient when producing 120F (or less) water.  This makes the heat distribution more challenging, and makes some of the conventional systems difficult to use  because of their reliance on high temperature water.

If you have any additional ideas, please let me know. 

The new section is here....


A rather neat homemade radiator for heat distribution at the Dawson Creek, YT Visitors Center.

I also updated and added some material to the Heat Exchangers for Solar Heating Systems section...  Again, the emphasis is on DIY approaches.

Gary

A well designed compost furnace for space/water heating

Marc has worked out a what appears to be a very nice design for extracting heat from a large compost pile for space heating.



Marc's design includes a blower and air supply manifold system to aerate the pile, a pipe network to add water to the pile as needed, a pipe network to extract heat from the pile, insulation to increase the efficiency of the composting process, and a nice containment and cover system.

Link to Marc's blog entry on heat from compost...

Other heat from compost schemes on Build-It-Solar...

Judging from the emails I get, there is a lot of interest in using compost to generate heat, but there is not a lot of detailed information out there on how to actually build such as system.  I think Marc has taken a good cut at it.  What do you think?

Gary

The Solar Dinosaur

OK, I suppose its a little bit of a stretch to call this a SOLAR dinosaur, but it does have a solar powered Dino Horn and a rotating Dino Beacon!

This is a dinosaur theme play structure that we built for the grand kids.  If you should be unbalanced enough to want to duplicate it, the picture plans and construction details in agonizing detail are here...   (free as always)


 

Gary

Installing Your Own Grid-Tie PV System

Guy Marsden goes through the whole process of designing, building, and installing a grid-tie PV system for his home. 


Guy and friends finishing the install.

The system uses the new Enphase micro inverters.  In this scheme, each PV panel gets its own inverter, which is installed on the back of the PV panel.  The output from the inverter is 230VAC.  The 230 VAC outputs from the inverters are tied together and hooked to your circuit breaker box via a regular circuit breaker.  Each inverter is UL certified for a grid-tie connection, so this is basically the all there is to it.  Power generated is monitored and reported by the Enphase Envoy unit.  The Envoy monitors and reports on each microinverter, and provides troubleshooting and power output reporting on the Enphase website.

Details on Guy's PV system...

Much more information on doing your own PV system...

While this system does simplify the installation, it is still a big job, and there are serious safety issues to be understood and deal with -- so, if you plan to do your own installation -- do your homework first!

Gary

Energy Fairs

This is the season for a lot of the annual energy fairs, so check around and see if there is a good one to go to in your area.

The fairs are a great way to learn about renewable energy projects, go to workshops, meet some renewable energy people in your area, and find some deals.

I keep a list of all the Energy Fairs I know about here...

If you know of others that are not on the list, please let me know...

Gary

Collector Fins from Tom's Super Press

Sometime back Tom built this super press for making the grooved fins for our homemade solar water heating collectors. Tom has indicated that time and material permitting, he is willing to make plates for others -- details here...

Tom is a long time friend of Build-It-Solar and has contributed plans for several very well done projects.



These appear to me be to be very well formed plates, and very likely will perform better than commercially made heat spreader plates.

If you are wondering what in the world this is all about, see this entry on construction the solar water heating collectors that use these plates...

Gary

Another very detailed "How-To" on Building PV Panels from Cells

On his website, Hange provides a very detailed set of instructions and pictures on how to build PV panels from individual PV cells...   The site covers finding cells, laying cells out to make a panel, soldering instructions, and glazing instructions...  



Several other articles on building your own panels...


Gary

Gordon's "$1K" Solar Water Heating -- From New Zealand

Gordon has provided details on how he built his version of the "$1K" Solar Water Heating system.  These systems are high quality, high solar fraction, all climate solar water heating systems that you can build for about $1000 in material costs.

Gordon's system adapts the design to his situation, his changes include:
- A well made, high tilt angle roof mount for the collectors.
- An all copper, single pass heat exchanger that pre-heats water before it gets to his existing hot water heater




Full details and build instructions on Gordon's Solar Water Heating System...

More examples of the "$1K" type solar water here...

Gary

Home Build PV Panels and System

In this new article, Hans describes in detail the solar electric (PV) system he built from the solar cells up.  The system includes 3 homemade PV panels, as well as the balance of system components to make a full functioning solar electric system. 

Full description of the PV system ...


Hans maintains a web site that provides more information on the project as well as other renewable energy projects.

Gary

August Performance for the $1K Solar Water Heating System

The performance for $1K Solar Water Heating System is in.   This is the day by day performance plot. 

The solar fraction for the month was 100%.

I'm going to continue the logging through September so that there is a full year of monthly performance plots.

Here is a road map of all the pages on the design, construction, testing, and performance for the system.

An Exceptional Residential Energy Retrofit

Normal
0




false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

Gordon and Sue took a drafty 1963
brick schoolhouse with almost no insulation and converted into a home that
could meet Passive House Institute standards, and that has a heating bill that
is 6% of a similar size code built home in their area.   Building a
new home with a thermal envelope this efficient would be an excellent
accomplishment -- doing this in a retrofit situation with all the challenges
that go with trying to bend an existing structure to your needs makes it much
more difficult.   Meeting nearly all of the space heating needs with
a good thermal envelope and passive solar heating was a very difficult
challenge in this tough 7,150 heating degree day climate in Ontario.  On
top of all this, the house looks normal and fits into its neighborhood just
fine.

Full details...





Normal
0




false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

This is the most carefully thought
out and carefully executed energy retrofit I have seen.  

Some of the features of the retrofit include:
R40 Larsen Truss walls, triple glazed R6 super windows, glazing revamped for
passive solar heating, a new solarium, a hand crafted masonry heater, and much
more.  In addition to a very good thermal envelope, Gordon gives a lot of
attention to fire safety and to redundancy in the space heating system. 
Like most good designs,

Normal
0




false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

this
one is simple and robust without a lot of gadgetry.



Gordon has done a very good job of describing the logic leading up to the key decisions on the insulating, glazing, passive solar, and thermal mass solutions used in the final design.  He has also described some of he things that did not go so well, and why -- all good information for would-be rettrofitters.

 

The
full details include a 30 page description of the design and construction
process, an extensive photo gallery covering all stages of the project, and a
very detailed thermal analysis spreadsheet.  

 Gary

v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}



Normal
0
false



false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}




v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}



Normal
0
false



false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

EcoRider -- Converting a riding gas mower to electric

This is an interesting ongoing set of entries on the Eco-Renovator site about converting a riding gas mower into an electric operation running on lead acid batteries.

This could become a solar charged mower with the addition of PV panels and a charge controller.

Details on the EcoRenovator conversion here...

More on converting mowers and tractors to solar electric operation...

 

The EcoRenovator site has a number of interesting articles.

Gary

Single Seat VW Car to Get 250 mpg -- Production in 2010

This
single seat car that VW is working on would get 250+ mpg, top speed 75 mph. 
It can travel over 400 miles on its 1.7 gallon fuel tank! 

It weighs 660 lbs.

This car is powered by gasoline only, and its 250 mpg is not one of the
phony plug in hybrid mileage ratings that does not include fossil fuel
burned to make electricity -- its an honest 250 mpg -- amazing.













Said to be ready to go on sale in Shanghai in 2010. 

More here...

Gary

Matt's "$1K" Solar Water Heating System

This is Matt's version of the $1K type solar water
heating system.  Matt tried a few new things that might be just what you
are looking for.  One of Matt's innovations is what might be the worlds
first bicycle powered groove forming machine!

Matt is a very good craftsman, and
provides a wealth of interesting alternative ways of making the components.

 

Some of the unique features of Matt's
system:

- A unique forming machine to
form the groove in the aluminum fins.

- A new method of attaching the fins to the copper tubes.

 

- A copper heat exchanger that
uses 6 parallel coils of 3/8 inch copper pipe.

 

- a galvanized metal collector
frame.

 

- A steel tank instead of the
EPDM lined plywood tank.

- Glass for glazing instead of polycarbonate.

Thanks very much to Matt for taking
the time to document this project!

All the details on Matt's system here...

For those who have not seen it, the $1K Solar Water Heating system aims at providing a quality solar water heating system with a high solar fraction that is simple and easy to build and will work in cold climates.
All the details on the $1K system here...

More examples of $1K systems here...
Gary

New Product: Nissan LEAF EV for US in 2010

Nissan Motor Co. has announced that they plan to offer the Nissan LEAF pure electric car in the US in late 2010.
The LEAF seats 5, and will have a range of about 100 miles.  It uses a 24 KWH Lithium-Ion batter pack.  Top speed of 90 mph.

More info here...

Getting the 30% Federal Tax Credit on a DIY Solar Water Heating System

Normal
0




false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

I've received several emails from people who would like to
build the $1K Solar Water Heating System, but who also don't want to miss the
30% federal tax rebate that is part of the new Energy Bill -- I think you can
do this.

The new federal rebate for solar water heating systems offers a 30% tax credit on the full price of the system.

One of the requirements is that the collectors used in the
system must be certified by the SRCC under their OG-100 program.  Since its only the collectors that must be
certified, you can
build and install your own system and get the tax rebate as long as you use a
commercial collector that is SRCC certified, as most commercial collectors are.

As an example, if you were planning to build
the $1K system with a homemade 40sqft collector, you could substitute (say) a
Heliodyne Gobi 40 sqft collector .  This
will make the entire system qualify for the rebate.  The numbers might work out like this:

The $1K system costs                      $1000
Delete homemade collector         -$200
Add commercial collector            +$1000
--------------------------------------------------
Total cost of system                       $1800

Minus 30% rebate                            $540
----------------------------------------------------
Cost after rebate                              $1260

So, this approach increases the cost of the system a bit, but you get a nice shiny commercial collector, and avoid the work of
making a collector.  You also end up with
a solar water heating system that is about 1/5th the cost of a professionally
installed commercial system, and that will pay back your investment in a fairly
short period.

So, this is a good deal for you, and an even better deal for
the feds in that they are paying a rebate of only $540 instead of a typical rebate
of $2400 on an $8000 system -- as Barack would say, win-win!

Another approach would be to buy off the shelf components
for the full system and install them yourself. 
You save the cost of the installation, and you get the rebate.  Lots of material on how to install a system here...

Most states also have a rebate or tax credit program that might further reduce the cost of the system.  For example, my state (MT) offers a $500 tax credit on solar water heating systems with no stings attached.  Information on state programs here...

Normal
0




false
false
false

EN-US
X-NONE
X-NONE













MicrosoftInternetExplorer4





























































































































































/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-qformat:yes;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin-top:0in;
mso-para-margin-right:0in;
mso-para-margin-bottom:10.0pt;
mso-para-margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:"Times New Roman";
mso-fareast-theme-font:minor-fareast;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}

Disclaimer: I'm not a tax expert, so you might want to do
some checking of your own on this.

Gary

    

Insulating Underground Pipe Runs

If your solar collectors are located away from your house, you will probably want to run the supply and return pipes underground from the collector to the house.  Insulating these pipe well is important in order to avoid a lot of heat loss to the ground.

I've added a new section to collect schemes for insulating underground pipe runs:
http://www.builditsolar.com/Projects/SpaceHeating/Space_Heating.htm#UGPipes
Currently it shows the scheme I used on my Solar Shed, a commercially available solution.



































The new section also shows an interesting method suggested by Don Stephens (of AGS).  He makes mix of Portland cement and polystyrene foam beads (as in foam coffee cups).  This is similar to the building material called Rastra, and has an insulting value around R1.7 per inch.  He lays down a thick bed of this in the trench and waits it to harden, then he fastens the PEX pipe lines down with large staples, which apparently are easy to embed in the soft cement.  He them pours a 2nd thick batch of the bead-crete over the pipes.  Once its dry, he covers with poly film and backfills the trench.  Because of the relatively low R value per inch, you would have to use a greater thickness than for something like XPS rigid foam, but it may still be cheaper and easier to do this.  Don's more detailed description is at the link above.

If you know of any other good schemes, please let me know.

Gary

July Performance for the $1K Solar Water Heating System

The $1000 Solar Water Heating System has been in operation for nearly a year now.  I've been logging the tank, collector, and ambient temperatures and posting the plots of these temperatures at the end of each month.

So, here is the July one:

As you might expect for the middle of summer, the solar fraction was 100%.

This month was a test of the strategy to keep the stagnation temperatures within the limits of the PEX tube used in the collector, and it appeared to do OK with a maximum collector temperature of 195F.

More details on the $1K system...
Performance plots for the last 10 months...

Gary

Window Condensation Calculator

Insulating shutters or window treatments that fit inside the window are a very cost effective way to reduce heat loss from windows.  We have a section on insulating window treatments that provides a raft of ways to do this.  I got an email from Dave in the UK pointing out that these kinds of insulating window treatments can also cause condensation on the inside window surface, and that this can be a problem.

I gave Dave some kind of vague and not very helpful answer on humid vs dry climates and the like.  Dave, being more of an engineer than me, was not satisfied with generalities, and came up with this very nice Window Condensation Calculator that can be used to predict exactly how much of an insulating treatment you can add before getting condensation -- yea Dave!

An insulating treatment installed on the inside of a window increases the likelihood of condensation forming on the window because the added insulating value of the treatment lowers the window surface temperature.  If the window surface temperature is lowered enough, it goes below the dew point of the room air, and condensation begins to form.  The lower the window surface temperature and the looser the window treatment fits, the more condensation you will get. 

There are basically two ways to address the problem:

1. Use a window treatment that fits snugly enough that very little air circulates between the window surface and the insulating treatment.
   
   
2. Choose a window treatment with an R value low enough that the window surface will not go below the room air dew point.  

Dave's calculator tells you what  the highest R value window treatment you can use and still avoid condensation on a loose fitting thermal shade -- very nice!
Dave's condensation calculator is based on Wolfgang's Dewpoint Calculator -- also very handy.

It turns out that this critical R value depend on:

• The room temperature and relative humidity
  
• The outside temperature
• The R values of the existing window and the insulating window treatment.

The room temperature and relative humidity allow you to calculate the dew point, and the two temperatures and 2  R values allow you to calculate the surface temperature of the inside of the glass.

Condensation is less likely with lower room humidity, warmer outside temperature, higher R value windows (e.g. double glazed), and lower R values for the insulating shutter.  You also get less condensation if the insulating shade fits tightly enough to reduce air flow between the shade and the window.   So, by playing around with these values, you should be able to find something that works in your situation.

Climate has a big influence -- our area is so dry that even though we routinely get below zero F temperatures and have high R value thermal shades, we rarely get condensation -- occasionally on VERY cold mornings we do get some beautiful frost patterns on the inside of the window glass.

Anyway, thanks to Dave for going the extra mile.

Gary