Saturday, September 20, 2008

Passive solar home construction




So, if you have seen my previous posts and video's you will know what I have been up to, building an energy efficient passive solar home. The video link on this post is the final part of the foundation system, which was the most difficult part of the project. Many people have commented on how different the foundation looked upon casual observation. If they only knew how different this was in comparison to a traditional foundation. Here in New England we are one of the few places were people feel the need to put a basement under our homes, for most of the country the slab-on-grade foundation system is conventional construction. Of course we do have some specific requirements when it comes to insulating and heating our homes in this region. This requires a different approach to building, rather than have our foundation being an energy drain on our building we actually use it to our advantage. The thermal mass contained within the foundation allows us to use it to store the homes energy at a constant rate. Once the slab is brought to temperature the energy needed to maintain this is very low, and at a very low temperature. We will be able to heat this home with water at a temperature of 85-90 degrees F. most conventional baseboard heating systems require a water delivery temperature of 160-180 degrees F. The low delivery temperature of the heating system is the key factor that allows the geothermal heat pump to deliver all of the homes heating and cooling needs.






As I am writing this, I have already finished installing most of the Structural Insulated Panels, used for the envelope of the home. I have taken some video of this as well and will post it when time allows. The SIP's showed up on the site on Tuesday afternoon around 2pm. and by this afternoon we had just 3 gable panels to finish installing before moving on to the ceiling panels. These will be in place tomorrow or is it today? The roof framing is scheduled to start on Monday with the hope of finishing it along with some trim by the end of next week. This portion of the project will continue at a fairly fast pace as we push to prepare for a open house scheduled for October 4th.






The most exciting thing we are using in this home is a prototype window system under development by Hunter Douglas. If we have our roof shingles on the roof as scheduled these windows will be installed for the open house. This window system is in my opinion the best innovation in passive solar to be developed in recent years. It contains a very specific glazing along with glass blocks filled with water to store the suns energy and regulate how it is transmitted into the home. Not only is it functional, but very attractive as well. I will continue to post videos and pictures of the project as we move forward.

more pictures of the project http://picasaweb.google.com/TomPittsley/PassiveSolarHomeUnderConstruction#




Thanks Tom Pittsley


http://www.eebt.org/


ecobuilder@aol.com

Saturday, August 16, 2008

Passive Solar construction

New Passive Solar home under construction
in Middleboro MA


Video's of the project









We have begun construction of this new energy efficient passive solar home of the future.


Designed to use the natural ability of the sun to heat the home, with an innovative thermal mass window system that is the in my opinion one of the best passive solar products to be developed in recent years. This window system will allow us to store the suns energy without overheating the space. Traditional passive solar homes had large windows with large spaces and lots of thermal mass ( concrete, stone ). When the sun was shining and the house was charging itself up with the suns energy, the spaces within the house were sometimes unbearably hot and very very bright, resulting in a space that was mostly uninhabitable for much of the day. This system will allow us to modulate the suns energy while storing it within the window system, tinting options are available to control light levels for comfort. This prototype window system has been under development by Hunter Douglas for many years and this is the first real world installation of there latest design. If you want to be one of the first to see this innovative home we will be having tours at intervals during construction. As well as being part of the NESEA's green building open house http://www.nesea.org/buildings/openhouse/ .

For more info check out www.eebt.org/passivesolar.html

Features of the house



  • Passive solar orientation
  • 150 sqft of specialized thermal mass south facing windows
  • Geothermal heating and cooling
  • Insulated slab on grade foundation with integrated radiant floor heating and cooling
  • Structural Insulated Panels wall system ( SIP's ) walls R-26 ceiling R-40
  • SIP's allow for minimal air infiltration, on of the largest heating losses within a home
  • One floor living, making the space adaptable for handicapped accessibility
  • Energy recovery ventilation system
  • drop down exterior window shades along south side, for solar control
  • Energy star appliances and lighting
  • 1,976 sqft 4 bedrooms, 2 bath, kitchen
  • Stained concrete floor through, enhancing the beauty of the house while boosting the performance of radiant floors heating system.
  • Primary entrance designed as an airlock system to reduce transfer of thermal loads while heating or cooling.
  • Zero Energy adaptable, the roof is designed with adequate space for PV to supply the home. Once the home is up and running for at least one year the PV system will be designed to meet the homes needs.
  • Centrally located utility room to reduce plumbing and electrical runs

I have set some very high goals for this home and will be recording the performance over the course of the next few years. If my calculations are correct I expect the heating costs for this New England home to be less than $700 annually. With an anticipated total energy bill of less than $1,500 annually.

The ultimate goal for this home would be a total annual energy bill of less than $1,000 , we shall see, if this performance level is reached you would need a 5KW Pv array to meet the homes total energy demands. This is not an inexpensive option, but on worth fully exploring. The cost to convert this home to a Zero Energy home would be an additional $50,000, and would make it a Zero Carbon home as well. Stay tuned updates will be listed on my web page www.eebt.org/passivesolar.html

The goethermal horizontal ground loop is being installed Monday, I will post some pictures and video when it is done.

Thanks Tom Pittsley

ecobuilder@aol.com

Friday, May 9, 2008

passive solar home with a dark shade of green

Update: 6/28/08 This 2,700 sqft passive solar home located in Massachusetts had a heating bill of $700 last winter.



So what do you think of passive solar design? I personally feel it should be of some, if not the primary focus of designing a home for efficient use of energy. The home described in the blog is one that has proven to me that passive solar design works and works well, when used in conjunction with super insulated envelope systems. Here is a list of systems, materials and designs which make this passive solar home work.

Pictures http://picasaweb.google.com/TomPittsley/PassiveSolarHome
http://www.eebt.org/Rochester.html

Orientation of the home for maximum solar gains in winter
Large amounts of high solar heat gain windows on the south facing wall
Overhangs designed to provide shading of the windows in the summer
Integrated window shading system to control the flow of heat through the south facing windows
Small and few well insulated windows on the north, east and west facades
Solar hot water system to be added this fall, all the pieces are in place to make the connections

Concrete slab floor with radiant floor heating system, located for maximum direct solar gains
Thermal mass was achieved with the Insulated concrete forms, used for the first floor and basement walls.
Structural insulated panels were used for the roof, dormers and gables R-49
Cold roof system was utilized for proper venting of the roof system and longevity
Energy recovery ventilation system for providing just the right amount of fresh air 82% efficient
Baxi on demand propane fired boiler for domestic hot water and heating 95% efficient


Some green materials that were used that did not directly have a relationship with how energy was used within the home, but rather home much energy was used and save by recycling building materials. All of the exposed yellow pine structural beams and posts of this home are recycled and re milled locally, from old mill structures scheduled for destruction. Not only the posts and beams, but all of the hardwood flooring and railings are also from this source. This is not an inexpensive alternative, but the incredible beauty and strength of old growth lumber is something you cannot find at the local lumber yard ( or the depot ). There are many more features of this home that contribute to it being a very green home, but I have been long winded enough.

Tom Pittsley
ecobuilder@aol.com
http://www.eebt.org/