Archive for the ‘Geothermal’ Category

Starting on the Wine Cellar

Tuesday, January 4th, 2011

We have a lot on our list and, although it should be a low priority, our Wine Cellar is high on our list.

The Wine Cellar is important because it is integrated with our geothermal heat exchange.  Essentially, we will be creating a tank of hot water and a tank of cold water.  The hot water will be used to heat our domestic hot water and to heat our house.  The cold water will be used to cool our house.  When we are in ‘cooling mode’ we will take the waste hot water and dump it into our swimming pool.  When we are in ‘heating mode’ we will take the waste cold water and dump it into our Wine Cellar.

Integrating our system requires that we consider each of the elements in order to complete the design.  So, spending some valuable time at this point in the project on our Wine Cellar is prudent since it will help us complete the geothermal design and implementation (construction).

Of course, the layout and design of the Wine Cellar must be functional and pleasing to the eye.  We’ve done plenty of research on wine cellars, including our visit to St. Maarten last year.  Bryan visited K&L Wine Mechants in Redwood City several times to review the construction details of their racks.  He took a number of photos during his visit to their branch on December 12, 2010.

Wine Cellar Design Alternatives

We need to finalize the ceiling height and cooling panel design components so we can establish our design and definitive cooling panel layout.

The big question that we needed to answer were related to the size of the aluminum panel that would take the BTUs from the wine bottles and move that energy to the heat exchange unit (where it would go to wherever there was a heating call).

This answer requires exact dimensions and cooling load requirements.

Mocking Up the Wine Cellar Racks

We spent several days ensuring that our wine racks would be consistent and symmetrical.  We took the dimensions of our ‘space’ and sent that information to several wine rack manufacturers and they provided us with layouts and dimensions of what they could do.  At the same time, we do have Al and Nep to work on fabricating and installing the wine cellar.

After analyzing the Wine Cellar, we decided that we would only use Redwood and stainless steel inside the Wine Cellar.  There will be no finishes inside the Wine Cellar – all the wood and surfaces will be natural and not coated with any stains, paints, etc.

Our decision criteria for the unfinished materials include durability and the resistance to corrosion. Although we will be controlling the humidity of the air inside the house, the Wine Cellar will definitely be more humid than the rest of the house.  With the increased humidity, the air will also be much cooler (57°F) so we will be very close to the dew point with the humid air (if the air is too dry then the corks will shrink).

Given our situation with tight spacing and our desire to fill the space completely, we have to assemble the various components of the wine racks inside the Wine Cellar.  Although it may seem trivial, it is not (go figure!).

It felt good to get the first mock up of our wine rack completed and located in the appropriate position inside our Wine Cellar.

Now we can complete the design of the cooling panels in the ceiling.

Cheers!

Starting with the concrete 'box', located under the garage.  The 2x4 sleepers on the floor will be used to attach the racks to the foundation and to raise the hardwood floor off the concrete.

Starting with the concrete 'box', located under the garage. The 2x4 sleepers on the floor will be used to attach the racks to the foundation and to raise the hardwood floor off the concrete.

The mock up of the North wine rack is in place.  In the mock up, we built a rack to hold one 750 ml and 1.5 l bottles in the smallest location to verity the fit.

The mock up of the North wine rack is in place. In the mock up, we built a rack to hold one 750 ml and 1.5 l bottles in the smallest location to verity the fit.

This wine rack will be very tall (105 inches from finished floor to the top of the rack) and is designed to hold 820 750 ml bottles and 16 1.5 l bottles.

This wine rack will be very tall (105 inches from finished floor to the top of the rack) and is designed to hold 820 750 ml bottles and 16 1.5 l bottles.

The profile of the North rack, which is a mirror image of the South rack, is one bottle deep at the top and two bottles deep at the base.  There will be two rows of display bottles that will be at an angle.  The counter will be granite.

The profile of the North rack, which is a mirror image of the South rack, is one bottle deep at the top and two bottles deep at the base. There will be two rows of display bottles that will be at an angle. The counter top will be granite.

The North (and South) racks are taller than the dropped ceiling and will be two inches below the aluminum cooling panels.The ceiling will be dropped by six inches so it can be insulated.  Overall, the finished ceiling will be 9-1/2 inches lower than the bottom of the hollow core concrete panels shown in this photo.

The North (and South) racks are taller than the dropped ceiling and will be two inches below the aluminum cooling panels.The ceiling will be dropped by six inches so it can be insulated. Overall, the finished ceiling will be 9-1/2 inches lower than the bottom of the hollow core concrete panels shown in this photo.

The bottom of the North rack, showing the space that ill extend across all three racks (North, center and South).  The hardwood flooring and redwood ceiling in this area will match the flooring and ceiling in the Wine Dining.  However, there will be six inches of crushed rock around each of the racks and the walkway between the racks will be perpendicular to the hardwood flooring that continues from the Wine Dining.

The bottom of the North rack, showing the space that ill extend across all three racks (North, center and South). The hardwood flooring and redwood ceiling in this area will match the flooring and ceiling in the Wine Dining. However, there will be six inches of crushed rock around each of the racks and the walkway between the racks will be perpendicular to the hardwood flooring that continues from the Wine Dining. Reed Kingston recommended (strongly) that we include sufficient space to walk from the North aisle to the South aisle without moving the sliding glass doors (does this look ok Reed?).

Mocking Up Our Zinc Fascia

Tuesday, December 14th, 2010

We mocked up our zinc fascia today.  And put three yellow cedar shakes on.  It is cool.  Way cool.

After we finalize the design, the installation crew from Wildcat Metals will arrive on our job site on Thursday morning so they can work through and finish putting the zinc facia on the gables by Tuesday, December 21.  The natural zinc material is from Rheinzink and the yellow cedar shakes are from BCF Shake Mill in Shanty Bay, Canada.

Time in 2010 is dwindling quickly – we leave for Edmonton early on December 22.

Designing the Cooling Panel System in Our Wine Cellar

Our home will be heated using geothermal heat exchange.  As a byproduct of making hot water, we will make cold water.  That cold water will be put back into the ground.  Instead of putting the cold water back into the ground and making our overall geothermal system less efficient, we will use the cold water to chill our wine in the Wine Cellar.  How cool is that?

Way cool …

While a great idea, using the waste cold water to keep our Wine Cellar cool requires an immense amount of design work.  Fortunately, we have an outstanding design team!  Markus Benzenhofer, from Twa Panel Systems, and Ken Martin, from Silicon Valley Mechanical are world class professionals, and know how to move BTUs from room-to-room, and from the exterior of a structure to inside that same structure.  And, of course, visa versa. 

Bryan met with Markus today to specify the cooling panels for the ceiling of the Wine Cellar.  As well, there are other aspects of the design that they reviewed, including how to move the chilled water to and from the West Mechanical room.

They took detailed measurements so Markus could calculate how many BTUs could be ‘dumped’ into the Wine Cellar and how those BTUs could be controlled by the system that Ken Martin is designing.

The mechanics of moving the waste cold water to the Wine Cellar is important as the structural elements of the Wine Cellar must be designed to work effectively.  The order of construction must be determined as well as the structural strength required by racks that hold the wine bottles.

If the capacity of the Wine Cellar is 2,900 750-ml bottles and each bottle weighs 1.0 kilo then the total weight of each of the three racks (when full) will be more than 2,000 lbs.  When we experience an earthquake of, say, 8.8, we don’t want the wine rack to collapse.  575 gallons of wine would make a huge mess.  The wine racks must be strong.  We don’t want to cry over spilled wine (but we would).

During the discussion, Markus raised a very important point.  We should consider having some ‘fast’ heating in the Wine Dining as anyone in there needs to be comfortable in order to enjoy the wine.  We will consider and evaluate using electrically operated radiant in the floor where people will be seated.  This is important, especially for Jo-Anne’s comfort (Bryan can suffer cold feet, Jo-Anne cannot).

The first piece of natural zinc is fastened to the gable rake fascia over the Garage.  It looks great!

The first piece of natural zinc (from Rheinzink) is fastened to the gable rake fascia over the Garage. It looks great!

Bryan took three shakes and used a 1-inch overhang to see what the shakes would look like.  We could probably have the seam extend anothe 1/2 inch, so the flat expanse of the zinc would be reduced.

Bryan took three shakes and used a 1-inch overhang to see what the shakes would look like. We could probably have the seam extend anothe 1/2 inch, so the flat expanse of the zinc would be reduced.

We measured the zinc fascia seam on the lower flat roof and it must change.  We'd like to keep the same proportions with the gable roof rakes so the seam on the lower flat roof should be at 10-1/2 inches (not 11-1/2 inches),

We measured the zinc fascia seam on the lower flat roof and it must change. We'd like to keep the same proportions with the gable roof rakes so the seam on the lower flat roof should be at 10-1/2 inches (not 11-1/2 inches),

Touring Twa Panel Systems’ Manufacturing Facility in Nisku, Canada

Friday, October 8th, 2010

Since we (Bryan, Jo-Anne, Nik and Kate) were going to Edmonton, Canada to visit Bryan’s family for Canadian Thanksgiving, Bryan took the opportunity to visit Twa Panel Systems, Inc. in Nisku, Alberta.  Markus Benzenhofer arranged for Bryan to meet with Dave Selmser and tour the manufacturing facility.

Background

We are using geothermal heat exchange and a ground source heat pump to heat and cool our house.  The system that Ken Martin, from Silicon Valley Mechanical, refined the design of includes two insulated water tanks, one holding hot water and the other tank holding cold water.

The tank of hot water will be used to satisfy heating calls and the cold water for cooling calls.  In order to cool our wine, there will be radiant cooling panels in the ceiling of the wine cellar.  Actually, we will not be cooling the wine cellar but, rather, moving the BTUs (energy) from the wine cellar into the house (heating the house).

We met with Markus Benzenhofer of Twa Panel Systems, Inc. on October 29, 2009 at our project site.  Markus reviewed our required and completed the preliminary design of a radiant system that could meet our requirements.

Currently, Ken Martin is integrating and refining the preliminary design.

Touring Twa Panel Systems’ Manufacturing Facility in Nisku, Canada

Since we flew into Edmonton International Airport (YEG) at 12:30 pm and were being picked up, Bryan arranged to meet with Dave Selmser at 3:30 pm.  Nisku is just East of YEG so it was only minutes away from Bryan’s parents’ house in the South part of Edmonton.

Since Dave Selmser was in a meeting, Chris Tse showed Bryan Twa’s products that were installed in their building.  This was valuable before the tour of the manufacturing facilities as Bryan had not seen all of Twa’s products.

As soon as he was finished, Dave met Bryan and picked up where Chris left off.  Dave explained the evolution of radiant cooling panels and his role managing the modular active chiller beam product line at Twa Panel Systems.  All of the products manufactured by Twa Panel Systems are modular so a complete and integrated system can designed to work together using various components in a flexible manner.

Evolution of Cooling Panels to Chilled Beams

In describing the product line, Dave explained that the evolution of cooling panels started with radiant cooling panels in a ceiling.  These panels received chilled water and transfered heat (energy) from the room to the chilled water, heating the water, and then moving the water (heat) out of the room.  This system was inherently more efficient than moving chilled air into a room since water can carry more energy than air.

The evolution continued when the ceiling panels were perforated to allow air to flow around the radiant panels, using convection to increase the heat transfer from the room to the chilled water (heating the water), and then moving the water (heat) out of the room.

To increase the efficiency of the convection, the next phase of the evolution was passive chilled beams.  These passive chilled beams had fins attached to the copper pipes carrying the water into and out of the room.  The fins provided a larger surface area to transfer energy and relied on convection to move air over the fins.

Moving air over the fins was enhanced by the use of fresh air, supplied by the HVAC system.  The moving air was supplemented by small vents that would mix the incoming fresh air with existing air from inside the room, to increase the efficiency of the system while dramatically increasing indoor air quality.

Wikipedia includes a complete description of chilled beams, including the basic concepts and types of chilled beams.

Being picked up at Edmonton International Airport (YEG).

Being picked up at Edmonton International Airport (YEG).

Twa Panel Systems, Inc. facility in Nisku, AB, Canada.

Twa Panel Systems, Inc. facility in Nisku, Alberta, Canada.

Entrance to Twa Panel Systems, Inc. in Nisku, Alberta, Canada.

Entrance to Twa Panel Systems, Inc. in Nisku, Alberta, Canada.

Our host, Dave Selmser, at his desk ready to take Bryan on a tour of the manufacturing facilities.

Our host, Dave Selmser, at his desk ready to take Bryan on a tour of the manufacturing facilities.

Dave shows a modular passive ceiling radiant heating/cooling panel.  This panel is not finished.  Note the copper supply/return pipes.

Dave shows a modular passive ceiling radiant heating/cooling panel. This panel is not finished. Note the copper supply/return pipes.

Dave shows the back of the passive modular ceiling panel, with the copper pipe that transfers energy (heat) to the aluminum ceiling panel.

Dave shows the back of the passive modular ceiling panel, with the copper pipe that transfers energy (heat) to the aluminum ceiling panel.

Passive convection ceiling panels where air circulates through the cooling panels in the ceiling.

Passive convection ceiling panels where air circulates through the cooling panels in the ceiling.

Close up of the perforations in the ceiling where the air circulates.

Close up of the perforations in the ceiling where the air circulates.

Actual passive linear chilled panel in the ceiling.

Actual passive linear chilled panel in the ceiling.

Active chilled beam in the ceiling.

Active chilled beam in the ceiling.

Look closely and you can see the venturi for the active chilled beam.

Look closely and you can see the venturi for the active chilled beam.

 

Open ceiling panel, showing the finned cooling tubes that the air flows through.

Open ceiling panel, showing the finned cooling tubes that the air flows through.

New roll of soft, annealed copper for the modular chilled panels and chilled beams.

New roll of soft, annealed copper for the modular chilled panels and chilled beams.

Shaped copper piping for use in modular ceiling panels.

Shaped copper piping for use in modular ceiling panels.

Inventory of various extruded aluminum saddles and linear panels.

Inventory of various extruded aluminum saddles and linear panels.

Work in process - perfectly welded aluminum frames for modular ceiling panels.

Work in process - perfectly welded aluminum frames for modular ceiling panels.

New, Trumatic 500 CNC stamping machine for making perforations in aluminum panels.

New, Trumatic 500 CNC stamping machine for making perforations in aluminum panels.

Performations in sheet aluminum, made by the Trumatic 500 CNC machine.

Performations in sheet aluminum, made by the Trumatic 500 CNC machine.

Production area for linear panels.

Production area for linear panels.

Linear panels showing saddles ready for copper tubing.

Linear panels showing saddles ready for copper tubing.

Completed modular linear panel with copper tubing in place.

Completed modular linear panel with copper tubing in place.

Completed modular linear panels ready for packaging.

Completed modular linear panels ready for packaging.

 

Components for active chilled beams, ready for assembly.

Components for active chilled beams, ready for assembly.

Shroud for active chilled beam, ready for assembly.

Shroud for active chilled beam, ready for assembly.

Completed active chilled beam, ready for packaging.

Completed active chilled beam, ready for packaging.

Completed modular linear panels, ready for shipping to Rexall Center in Edmonton.

Completed modular linear panels, ready for shipping to Rexall Center in Edmonton.

Completed modular linear beams, in custom packaging (using Tyvek), ready to be picked up.

Completed modular linear beams, in custom packaging (using Tyvek), ready to be picked up.

Verifying the Effectiveness of Our Solar Design

Thursday, September 23rd, 2010

Darrel Kelly, John Rider and Joel Lemons arrived at our project site promptly at 11:45 am this morning to verify that the sun was now just starting to enter the house.  Bryan was there exactly at that time as he was returning from a site visit to an ultra-green residential project up the pennisula.

Bryan ordered the remaining roofing materials from Ford Wholesale, and picked up sufficient materials to get started until the bulk of the materials are delivered to the project site tomorrow (Friday) afternoon.

Visiting An ‘Ultra-Green Project’

Bryan was fortunate to visit another project up the pennisula that is being completed.  This project is very ‘green’ and has many similar construction components as our project, albeit on a larger scale.  We are particularly interested in the finishing materials being used in this project and the mechanical systems layout.

One of the challenges with sustainable construction is identifying and procuring materials and products that are produced locally in a sustainable manner that do not contain harmful compounds.  With our project, we need to specify the finishing materials and products that we require.  For example, we need to prime and finish wood surfaces throughout the house.  Also, we need fixtures and other products.

The surface area of the finished surfaces will be significant, so any off-gassing of volotile organic compounds (VOCs) is not acceptable.  Identifying and procuring zero VOC adhesives, primers and finishes is important for maintaining high indoor environmental air quality.  Essentially, we want to prevent pollutants from entering our home by not using products that contaminate the air inside our house.

Finding such products is difficult as the manufacturers of many products and materials bury the contents of their products in the MSDS (material safety data sheets) and it is time-consuming to research and identify acceptable products.  And, then one has to procure those products locally.

it is much easier and faster to visit a project where robust research has been conducted already to identify and procure acceptable materials, including adhesives, primers and finishes.  Bryan was fortunate to leverage such research on another project up the pennisula.

While at that project, Bryan reviewed the layout of the mechanical rooms.  The site he visited has a ground source heat pump using geothermal heat exchange and a mechanical system that uses multiple heat recovery ventilators.  The clothes dryers have booster fans and there is a whole-house water filtration system.  All components that we require for our home.

The mechanical rooms were well-lit with waterproof fluorescent light fixtures.  The layout of the room was simple and all pipes were labelled clearly.  Interestingly, the ground loop had a filter system to ensure the water flowing through the system was clean and had no particles in it.

The ceiling was constructed such that sound (vibrations) would be isolated to the mechanical room and not transmitted to the occupied areas above.  We need to consider sound deadening our West Mechanical room as our daughter’s bedroom is above the West Mechanical room.

Verifying the Effectiveness of Our Solar Design

The autumnal equinox occurred yesterday and our Green Rater, Darrel Kelly, came to our site at noon today to verify how much direct sunlight was entering our house through the windows.  John Rider and Joel Lemons, both from Jrider+Design, joined us to review the construction progress to date.  John did the original sun studies, using ArchiCAD.

Although Darrel, John and Joel subscribe to our construction blog and receive updates via e-mail, Bryan provided a brief overview of the status and project schedule.  To understand if the timeline was acceptable, Darrel simply asked, ‘Will you still be married at the move-in date?’ 

The group went into the lower level and noted that direct sunlight was entering the building through the sliding glass doors on the East side and the casement windows on the South side.  Bryan explained that we require solar gain in these locations because the earth is colder than the indoor desired temperature and, consequently, there is a heating load.  Importantly, the direct sunlight makes the lower level much more pleasant and immensely more habitable.  As the sun gets lower in the sky, the amount of direct sunlight entering the house in the lower level will continue to increase until the winter solstice.

Joel noted that the group should verify the amount of direct sunlight entering the house on the winter solstice.  Everyone agreed.

The next stop was the roof, to review the construction details for the top layers of the gable roof.  Bryan described the components and dimensions of the remaining layers of the gable roof (e.g., Cor-A-Vent, aluminum flashing, 1×3 furring strips, SecurRock, etc.).  Everyone agreed that the design and materials would result in a robust and enduring roof, that would be easy to maintain and have a long life.

Walking on the roof to the front of the house, everyone observed the crickets and how the flat roof had a slight pitch in all locations that will direct water to the drains and eliminate ponding.  Also, the brightness was observed and Joel commented on how this roof reduces the ‘heat island effect’ that is a problem in most urban areas.

Standing in the overhang of the gable roof in the Kitchen (over the garage), Darrel verified that a sliver of direct sunlight is now starting to enter the Kitchen.  As the sun gets lower in the sky, more direct sunlight will land on the concrete floor in the Kitchen and create some solar heat gain.  This is desired as the degree days increase after the automnal equinox.

Having verified everything at the site, the meeting moved to another location to discuss the subsequent construction activities and material selections.  Bryan showed the group the sample of ducting manufactured by Zehnder that we are evaluating and considering for our house.  The benefit of the ducting is that it is, like a plumbing system, very ‘tight’ and will allow us to use a heat recovery ventilator while utilizing displacement air ventilation.  Ken Martin, from Silicon Valley Mechanical, is working on the design of the system.

Picking Up Securock from Ford Wholesale

To ensure the team from Earth Bound Homes can start first thing tomorrow morning, Bryan picked up 22 sheets of 1/4-inch Securock and three rolls of 20-inch aluminum flashing.

We’re ready to start the gable roofs tomorrow.

The filter (green) and pump (red) for the geothermal heat exchange system.  Note the unstrut materials used.

The filter (green) and pump (red) for the geothermal heat exchange system. Note the unstrut materials used.

Mythic multi-purpose primer in a 5 gallon container.

Mythic multi-purpose primer in a 5 gallon container.

Rubio Monocoat Oil Plus finish, with 0% VOCs.

Rubio Monocoat Oil Plus finish, with 0% VOCs.

Joel Lemons (left), Darrel Kelly (taking photos) and John Rider (right) reviewing construction to date.

Joel Lemons (left), Darrel Kelly (taking photos) and John Rider (right) reviewing construction to date.

The supply and return lines on the West side of the house split into two ground loops, containing six piers in each loop.

The supply and return lines on the West side of the house split into two ground loops, containing six piers in each loop.

John Rider reviews the work to date on the roof.

John Rider reviews the work to date on the roof.

Roof access will be much different when the gable windows are installed.

Roof access will be much different when the gable windows are installed.

Everyone liked the sidewalk repair on Winchester Boulevard.  The pedestrians were happy, too.

Everyone liked the sidewalk repair on Winchester Boulevard. The pedestrians were happy, too.

Picking up SecuRock from Ford Wholesale in San Jose.

Picking up Securock from Ford Wholesale in San Jose.

Backfilling the South Trench

Saturday, September 11th, 2010

It was a grueling day today as Izzy and Bryan worked on backfilling the South trench (in front of the house).  Ryan Reyna and Nik helped for a couple hours, which was very much appreciated.

Underground Infrastructure

We have a lot going on in our trenches around the house.  The contents of the trenches are all different.  Here is a brief summary of the trench contents:

  • 4-inch ABS sanitary sewer drian pipes on the West side and South sides of the house
  • 4-inch ABS perimeter drain pipe that takes water from the seven (7) roof downspouts and various ground drains to the underground water cistern
  • 2-inch PVC electrical conduit from the East Mechanical room to the generator pad
  • 1-1/2 inch PVC electrical conduit from the East Mechanical room to the swimming pool equipment pad
  • 3/4-inch PVC water pipe for fresh water to the swimming pool equipment pad 
  • 1-inch PVC perimeter water pipe for irrigation water to the six irrigation manifolds
  • 1-inch PVC conduit for cables to connect and control the irrigation manifolds in six locations
  • 1-inch PVC conduit for proprietay cables for the natural gas powered generator
  • 1-inch PVC conduit for proprietay cables to control the swimming pool and spa equipment
  • 3/4-inch HDPE connecting the U-tubes in the 25 vertical concrete piers in four sections of 12 U-tubes each
  • 1-1/4 inch HDPE supply and return lines connecting the two geothermal ground loops
  • 2-inch HDPE supply and return lines to the swimming pool and swimming pool equipment pad
  • 2-inch HDPE natural gas line to generator and swimming pool equipment pad

Until the complete ground loop system is pressurized and tested successfully, and then inspected by the City of Monte Sereno, we cannot backfill the East, North and West trenches.  Similarly, we cannot backfill teh Swimming Pool and Generator trenches until the natural gas supply connections have been inspected.

The only trench we could backfill is the trench on the South side (in front of the house).

Except for the very West side and very East side, Izzy and Bryan backfilled and compacted the soil in this trench today.  Bryan will have sore muscles tomorrow.

The open trench at the South West corner of the house.  About 8 linear feet of this trench can be backfilled (it is still open).

The open trench at the South West corner of the house. About 8 linear feet of this trench can be backfilled (it is still open).

West trench looking North.  Note the 4-inch black ABS pipe stubbed for downspouts from the roof drains, the 3/4-inch HDPE connecting the U-tubes in the vertical concrete piers, the three 1-inch conduits for irrigation controls and the 1-inch PVC perimter pipe for irrigation water.

West trench looking North. Note the 4-inch black ABS pipe stubbed for downspouts from the roof drains, the 3/4-inch HDPE connecting the U-tubes in the vertical concrete piers, the three 1-inch conduits for irrigation controls and the 1-inch PVC perimter pipe for irrigation water.

North West corner of the house, showing where the ground loops will be combined in an underground vault.  Also, the conduit for the control wires (low voltage) will terminate inside the vault where they will be aggregaged and then enter the house in a single conduit.

North West corner of the house, showing where the ground loops will be combined in an underground vault. Also, the conduit for the control wires (low voltage) will terminate inside the vault where they will be aggregaged and then enter the house in a single conduit.

Trench going to generator and swimming pool equipment pad.  This is a full trench, with 4-inch ABS drain pipe, four 1-inch PVC conduits, 3/4 inch water line and a 2-inch HDPE natural gas line and 2-inch HDPE hot water return line to swimming pool pad.

Trench going to generator and swimming pool equipment pad. This is a full trench, with 4-inch ABS drain pipe, four 1-inch PVC conduits, 3/4 inch water line, 1-inch irrigation water line, 2-inch HDPE natural gas line and 2-inch HDPE hot water return line to swimming pool pad. The two 1-1/4 inch black HDPE pipes are the supply and return lines for the ground loops on the East side of the house.

Trench going around North West corner of pool, going to the generator pad and swimming pool equipment pad.

Trench going around North West corner of pool, going to the generator pad and swimming pool equipment pad.

New short trench going to swimming pool for 2-inch HDPE suction line to carry cold water from the swimming pool to cool the house.

New short trench going to swimming pool for 2-inch HDPE suction line to carry cold water from the swimming pool to cool the house.

Izzy compacting the backfilled trench at the South East corner of the house.  We compacted every six (6) inches.

Izzy compacting the backfilled trench at the South East corner of the house. We compacted every six (6) inches.

Izzy continuing to compact the entire trench at the South side of the house (front).

Izzy continuing to compact the entire trench at the South side of the house (front).

Backfilled and compacted trench at the front of the house.  Done ... for today.

Backfilled and compacted trench at the front of the house. Done ... for today.

Unfinished part of trench at East side of front of the house.  It would have been nice to have backfilled this small section today.

Unfinished part of trench at East side of front of the house. It would have been nice to have backfilled this small section today.

Entry to house is looking much, much better now.

Entry to house is looking much, much better now.

Installing Our 400 Amp Electric Panel

Friday, September 3rd, 2010

This week ended with two inspections scheduled for Tuesday, 09/07/10:  PG&E will perform the ‘mandrel inspection‘ and the City of Monte Sereno will inspect our mounting system and rough electrical for our solar photovoltaic panels.  We scheduled these inspections because we installed our 400 amp combined service entry device (400 amp electric panel) and all of the conduit and electric cables for the solar photovoltaic panels were run through to the appropriate points on the roof.

Bryan was confident that the weekly project review meeting tonight would go reasonably well.  Especially since he put two (2) bottles of Rombauer Chardonnay (Carneros 2008) in the fridge to cool …

Completing the Geothermal Ground Loop

The two-person team from 88HVAC, Justin and Michael, completed the test of our ground loop today.  Of the 25 concrete piers that go 30 feet into the ground with two U-tubes in each pier, we had one U-tube that failed (low water flow).  We could not solve the problem so we abandoned this U-tube and continued to connect all of the other U-tubes.

Bryan spent some time with Justin reviewing his recommendations for the valve configuration for our geothermal ground loops.  Justin presented several alternatives and they discussed each one.  The conclusion is that we will have copper pipe inside the house going to the underground concrete box in the North West corner of the house.  From this box, there will be HDPE pipes going to the four sets of concrete piers on the East and West sides of the house.

Although the copper materials have a higher cost, the labor cost will be the same or less to install the copper fittings.  Given the valves to isolate and control the water flow, copper fittings will have a smaller ‘footprint’ inside the flush mount concrete box.  The copper fittings will have a cleaner and simple layout and finish.

Background on Our 400 Amp Electric Service

We will have a 400 amp underground electric service.  Some people have asked, ‘with such an energy efficient house, why do you need a 400 amp service?’  The short answer is that there are code requirements that are a function of the size of the building footprint that determine the minimum amount of current that a house requires.  Since we do not have any natural gas coming into the house, we have electric cooktops and electric clothes dryers.  Although the calculated current is just under 300 amps, we will have a 400 amp service. Problems occur with too little electrical current, not more electrical current.

Mungo Hardwicke-Brown, who introduced Jo-Anne and Bryan in June 1991 when Jo-Anne was an Associate with Blake, Cassels & Graydon (now Blakes) in Toronto and Bryan was a Principal with Ernst & Young Canada, spoke with Bryan several times regarding our electric service requirements.  Currently, Mungo is completing a major renovation of his family’s home in Calgary, Canada.  Although he has a 200 amp electric service, he very much covets our 400 amp service.

The underground electric service enters our house through a 3-inch conduit.  This conduit goes through our concrete foundation wall and enters the bottom of our combined service entry device.  A ‘combined service entry device’ is the technical term for an electric panel that has an electric meter on one side and circuit breakers on the other side.  The side with the electric meter is only accessible to the electric utility and the circuit breakers on the other side are accessible to everyone else.  While we would have preferred separate components due to space constraints, the SU3040D400CN model from Square D (a division of Schneider Electric) is only 28-1/4 inches wide and costs less than a separate meter housing and distribution panel.

We will have four distribution panels, two of which will be in the East Mechanical room and two in the West Mechanical room.  One of the two panels in each mechanical room will house the circuits that will be connected to the transfer switch for our auxiliary backup natural gas powered generator.

Scott Andersen (from Toronto, Canada)  designed the electrical system so we could have two distribution panels in two different physical locations (one in the East Mechanical room and one in the West Mechanical room) that would work as one ‘virtual’ panel.  Scott, who has designed and built several unique lofts and homes in Toronto, completed the conceptual design for our house.  He is a partner with Burman & Fellows, which is an integrated commercial electrical contractor that focuses on grocery stores in the U.S. and Canada.  Scott designed the electrical distribution system to allow the auxiliary backup generator to provide power to circuits on each side of the house, the benefit of which would be reducing the amount of wire that needed to be run to the prioritized electrical circuits throughout the house.

Our electrical layout, as designed by Scott Andersen.  Note the two auxiliary backup generator provides power to two distributions panels, which are joined and act as a 100 amp single panel.

Our electrical layout, as designed by Scott Andersen. Note the two auxiliary backup generator provides power to two distributions panels, which are joined and act as a 100 amp single panel.

Installing Our 400 Amp Combined Service Entry Device

Doug and Josh, the two-person team from Certified Electric, arrived on schedule to our project site at 9:00 am to install our combined service entry device.  They cleared their work area and reviewed the plans with Bryan.  Together, they went through PG&E’s electric and natural gas service requirements, which specify the electric meter and natural gas meter location requirements and the layout of the East and West Mechanical rooms.

Also, they discussed where and how the combined service entry device and other distribution panels would be grounded.  The Building Official for the City of Monte Sereno, Howard Bell, advised us that we could use the two of the 30 ft long #7 rebar to ground our electric service provided that the two pieces of rebar were more than six feet apart.  We had identified the pieces of rebar previously and Izzy had removed the concrete from these two pieces of rebar.

With a solid understanding of the site, PG&E’s ‘Green Book’ requirements, and our requirements, Doug and Josh set to  work laying out the conduit and then cutting the wood studs and exterior plywood/sheathing for the electric panel. 

The bottom edge of the new electric panel will be at the identical height as the original 125 amp panel, which was installed in 1969.  Given the larger size of the 400 amp panel, the top and sides needed to be cut. 

Nothing that a new sawzall blade can’t make happen …

Josh measures and lays out where the 3-inch conduit will go into the bottom of the combined service entry device.

Josh measures and lays out where the 3-inch conduit will go into the bottom of the combined service entry device.

Doug, using a new sawzall blade, cuts the plywood for the 400 amp combined service entry device.  Note the location of the new panel is exactly where the original 125 amp panel was located on the East wall of the garage.

Doug, using a new sawzall blade, cuts the plywood for the 400 amp combined service entry device. Note the location of the new panel is exactly where the original 125 amp panel was located on the East wall of the garage.

The completed hole ready for the new 400 amp combined service entry device.  The plywood will support the panel until the framing is completed at a later date.

The completed hole ready for the new 400 amp combined service entry device. The plywood will support the panel until the framing is completed at a later date.

The back of our new 400 amp combined service entry device.  The disconnect for our solar photovoltaic panels will be on the left side of the combined service entry device.

The back of our new 400 amp combined service entry device. The disconnect for our solar photovoltaic panels will be on the left side of the combined service entry device.

Our new 400 amp combined service delivery panel, as viewed from the exterior of the house.

Our new 400 amp combined service delivery panel, as viewed from the exterior of the house.

Note the 7 reinforcing steel (rebar) that is exposed in the concrete pier.  This is one of two locations where our electric service will be grounded to the rebar that goes 30 feet into the earth.

Note the #7 reinforcing steel (rebar) that is exposed in the concrete pier. This is one of two locations where our electric service will be grounded to the rebar that goes 30 feet into the earth.

A completed concrete pier with our geothermal ground loop.  Note the connection at the bottom of the photo, which connects the two U-tubes in the pier.  Also, note the supply going into the first U-tube and the return coming out of the second U-tube.

A completed concrete pier with our geothermal ground loop. Note the connection at the bottom of the photo, which connects the two U-tubes in the pier. Also, note the supply going into the first U-tube and the return coming out of the second U-tube.

The adjacent concrete pier, showing the connection between the two U-tubes and the supply and return connections.

The adjacent concrete pier, showing the connection between the two U-tubes and the supply and return connections.

The only concrete pier with a blocked U-tube.  We are using the good U-tube in this concrete pier and have abandoned the defective U-tube.  49 of the 50 U-tubes in our 25 concrete piers were tested successfully for flow and pressure.

The only concrete pier with a blocked U-tube. We are using the good U-tube in this concrete pier and have abandoned the defective U-tube. 49 of the 50 U-tubes in our 25 concrete piers were tested successfully for flow and pressure.

The East wall in the East Mechanical room.  The seven wires in the box on the left will carry the current from the solar photovoltaic panels on our roof.  The panel on the right is connected by 2-inch conduit embedded in the concrete to the opening in the Garage and to the West Mechanical room.

The East wall in the East Mechanical room. The seven wires in the box on the left will carry the current from the solar photovoltaic panels on our roof. The panel on the right is connected by 2-inch conduit embedded in the concrete to the opening in the Garage and to the West Mechanical room.

We are considering locating two electric distribution panels on the North wall in the East Mechanical room.

We are considering locating two electric distribution panels on the North wall in the East Mechanical room.