Although relatively inexpensive today, we believe that water is a very important resource and we would like to be exemplary in our use of water.  Our strategy is to reduce our demand for water and then to supplement the demand for irrigation by utilizing our underground cistern.  We will capture 100% of the rainwater on our roof in our underground cistern.  All water pumped from below our foundation will go into our underground cistern. 

Oh, we had a nasty thorn removed from our side today when, after considerable prompting, the SAM storage unit was finally removed at 5:30 pm this evening.

Completing the Underground Connections for Our Water Catchment System

The key piece of infrastructure that we need is the water catchment system from our roof and hardscape to our underground cistern.  Bryan has been focusing on this for the past month and it is now coming together nicely.

Essentially, the perimeter of the entire house has an underground network of drains, all of which empty into our 3,677 gallon underground cistern.  Our lower flat roof, to which all of the roofs drain to, has seven (7) drains that must, ultimately, connect to our underground cistern.  In addition to these 7 roof drains, there are 12 other drains around the property that take water via the water catchment system to the underground cistern.

As of today, we have the drains in place around the entire property, with ’stubs’ to to each of the surface drains (on hardscape and otherwise).  This water catchment system needs to be connected to the underground cistern next week.

Testing Our Geothermal Ground Loop

The two-person team from 88HVAC continued to work diligently today as they tested our geothermal ground loop.  Well, to be accurate, our four geothermal ground loops.

We have 13 concrete piers on the East side of the house and 12 piers on the West side of the house.  These 20-inch in diameter concrete piers go 30 ft into the earth and are on 5 ft centers.  There are two U-tubesof 3/4-inch HDPE in each concrete pier, going the full length of each pier.

Of the 25 concrete piers, there were problems with one of the two U-tubes in two of the piers.  The problems were isolated to two specific U-tubes and, fortunately, Bryan was able to resolve one of the problems today.  The problem with the remaining U-tube may not be resolved, which leaves us with a ground loop of 2,940 ft (without the problem would be 3,000 ft).

Removing the Thorn in Our Side (i.e., the SAM Storage Unit)

At 5:30 pm, a truck arrived and picked up the offending SAM storage unit from Winchester Boulevard.

Bryan had called the company earlier today to request that the SAM storage unit be removed.  Actually, he called twice today.

It was good to see the SAM storage unit leave our neighborhood.

The drainage system behind our swimming pool, at the North end of our lot. Note the yellow natural gas line (2-inch) that supplies natural gas to our auxiliary backup generator and the pool heater.

The drain lines between the house and swimming pool.

The North West corner of the house. This is the highest point of the underground perimeter drains around the house.

The West side of the house has four roof drains as well as the 12 concrete piers for the ground loop.

Close up of the South segment of the West side of the house.

Loading the SAM storage unit onto the truck.

It was good to see the SAM storage unit being loaded on the truck. . .

On the truck ... goodbye!

We have a lot going on … connecting our geothermal ground loop, completing all of our underground drainage from the roof to our cistern and setting up the infrastructure for our photovoltaic solar panels.  The last thing we needed was someone to place a SAM storage unit by our property on Winchester Boulevard.

Importantly, the two-person team from 88HVAC, Justin and Mike, worked diligently to connect our ground loop between each of the 25 concrete piers.

A Dangerous Situation

The SAM storage unit on Winchester creates a dangerous situation in two aspects.  First, the SAM storage unit blocks visibility for vehicles turning left or right from Via Sereno onto Winchester Boulevard.  Second, the SAM storage unit blocks the 25 mph sign on Winchester, exacerbating the problem.  Essentially, vehicles travelling Southbound on Winchester can’t see the 25 mph sign and vehicles leaving VIa Sereno can’t see them coming.  And, the vehicles are approaching faster.

There are 16 houses on Via Sereno, of which we are one, leaving 15 others.  A neighbor up the  street called us last night and mentioned that they thought our new SAM storage unit was blocking visibility on Via Sereno.  We corrected them promptly, explaining that the SAM storage unit was not ours.  Then, they asked if it belonged to one of the workers or sub-contractors that we were using.  No, it was not. 

If one neighbor called to ask us about the SAM storage unit, we could only imagine that the other 14 neighbors were thinking the same thing but didn’t want to call us, yet. 

Bryan took down the SAM storage unit number (420-200338) and called 1-800-GET-ASAM to advise the company that the person renting the SAM storage unit was violating an local ordinance.  They took the information and then called back within 10 minutes to say the person renting the SAM storage unit would move it by 12:00 noon tomorrow (09/02/10).

Let’s see what happens tomorrow …

Welding Our HDPE for the Geothermal Ground Loop

As part of our lower level (basement), we had to excavate 13 feet of dirt under our existing house.  Since we wanted to use geothermal heat exchange through a ground source heat pump, the shoring required for the excavation had tremendous synergies with the geothermal.

Since we needed a ‘ground loop’ for our ground source heat pump, we placed our HDPE (High Density Polyethelene tubing) inside the concrete shoring piers.  Each of these piers went 30 feet into the earth.

At this point, we needed to connect the HDPE in each of the 25 concrete piers so we could extract the energy from the ground (or put energy from the house into the ground).

First, the two-person team from 88HVAC connected the two U-tubes in each of the 25 concrete piers together.  Now, they had to connect each of the 25 piers together into four individual ground loops (two on the East side and two on the West side).

The process was very interesting to watch:

1. Measure and cut the HPDE to the appropriate length.
2. Chamfer and clean the end of the HDPE so the melting/welding would be consistent and uniform.
3. Attach the cold pipe (special tool) to the HDPE with the chamfer tool in place.  The chamfer tool ensures the pipe length is measured accurately.
4. Using the special heating tool, heat both the male and female ends of the HDPE tubing and slip fitting.
5. Remove the heating tool, and connect and hold the two pieces of HDPE for at least 10 seconds.

Easy-peasy, right? 

Sort of.

After making the connections, the system is tested to 100 pounds per square inch (PSI).  It must hold 100 PSI and not have any leaks.

Each of the steps in the procedure described above must be done perfectly, otherwise there will be leaks.

Leaks can occur wherever the welds (molten HDPE) are not complete.  If there are areas where the welds are weak then failures may occur in those places over time.  Again, each step in the procedure has to be done perfectly to minimize the probability of incomplete welds.  For example, the HDPE must be at the correct length otherwise it will be difficult to hold the heating tool for the correct amount of time.  If the heating tool does not melt the HDPE sufficiently then there will be a weak area or the weld will not be complete.

The team from 88HVAC took the time and paid attention to detail such that the welds were done correctly.

Measuring the HDPE to identify where to make the connection between the two concrete piers.

Cutting the HDPE to the correct length.

Chamfer tool, which removes the correct amount of HDPE from the corners of the pipe and allows the cold ring to be locked into the correct position that will provide sufficient surface area for the heating tool (weld).

Cleaning the HDPE where the weld will be made.

Clamping the cold ring onto the HDPE in the correct location.

Using the heating tool to melt both parts of the connection at the same time. Each step in the procedure must be done perfectly to weld each of the two pieces of HDPE together. This is a critical step.

After the heating tool creates molten HDPE, the heating tool is removed and the two pieces of HDPE are connected quickly.

The completed connection must be held in place for at least 10 seconds so the HDPE cools to create a complete weld.

Completed connection. This connection, done correctly, will last for the life of the HDPE, which is more than 100 years.

Looking North on Winchester Boulevard, the view of oncoming (Southbound) traffic is impaired, which results in a dangerous situation.

The 25 mph sign is blocked by the SAM storage unit on Winchester Boulevard.

Vehicles Southbound on Winchester Boulevard cannot see the 25 mph sign (behind the SAM storage unit).

Not seeing the speed limit, vehicles tend to speed up, exacerbating the situation for vehicles turing left (or right) from Via Sereno. This is dangerous.

The number of the SAM storage unit, which was placed in a dangerous location on Wichester Boulevard without a permit issued by the Town of Los Gatos.

To keep ahead of Izzy, who was trenching and putting our underground water drainage sytem in place, Bryan made three (3) trips to RV Cloud (which is only a couple miles North on Winchester Boulevard).

Two 'sticks' of 20 ft long, 3 inch ABS pipe for Izzy (this will take water to our 3,677 gallon underground cistern). Good thing we have a truck with an overhead rack!

The seven (7) electrical wires coming from the solar panels on the roof to the storage space under the pantry. These cables will be run to the solar inverter in the East Mechanical room.

The installation team from Akeena Solar arrived at the job site this morning to install the mounting system on our upper flat roof.  Also, they pulled the ‘fish’ through the conduit to the storage space below the pantry.

At the same time, the two-person team from 88HVAC continued to connect the HDPE in the concrete piers on the West side of the house while Izzy backfilled and compacted the soil over the natural gas and electric conduit.

The week ended on a very positive note.

Installing the Solar Mounts on Our Upper Flat Roof

We worked with Akeena Solar to design our solar system so it would generate as much electricity as possible.  The East/West axis of our house is positioned within 13 degrees of due East/West and, on our upper flat roof alone, we have 624 square feet available for solar panels.  These factors meet two of the four requirements under LEED-H ID 1.5 Building Orientation for Solar Design.

For our latitude, the solar photovoltaic panels should be at approximately 23 degree tilt to optimize the generation of electricity.  Although we could have designed the system to have a single plane of panels then it would have been taller.  In addition, solar photovoltaic panels require periodic cleaning to maximize the production of electricity.

Since we had some space, but not sufficient space, on the roof to include walkway space between the four arrays of panels, we ‘terraced’ the arrays.  Terracing the arrays provides space between each array (row) of panels while reducing the shading of the panels by the array in front of it.

A non-terraced set of four arrays of solar panels would be taller than a terraced set and not allow easy access for cleaning the solar photovoltaic panels.

Terracing the set of four arrays lowers the overall height but requires more area for the panels. The wider the spacing between each array lowers the height of each subsequent array (the shading angle is 23 degrees for our latitude).

With the terracing, we required a frame for each array of eight panels.  These frames must be raised off the upper flat roof by mounts and these mounts will penetrate the roof membrane.  And, the conduit going from each array to the ‘combiner box’ must penetrate the roof membrane.

Detailed design on the mounts and frame for the arrays on the upper flat roof.

Duk Lee of Akeena Solar completed the detailed design of the layout and the frames (Sheet PV-1 and Sheet PV-2).  The onsite team was given the task to build the system.  The first step in building the system was to install the mounts on the upper flat roof and run the conduit on the lower flat roof that will be under the tapered insulation. 

Of course, the electrical and structural components of the system need to be inspected by the City of Monte Sereno …

The installation team from Akeena arrived on site as scheduled this morning.  They took care to park on Winchester Boulevard so their vehicles did not use any of the precious parking space on Via Sereno.  After an orientation and brief tour of the project, they set to work laying out the solar mounts.  Later in the morning, Duk Lee arrived to verify the layout was as designed.  As well, Ben Caschera, the installation manager with Akeena Solar came to the project site to see how his team was doing.

There were some difficulties with the ‘fish tape’ going through the dedicated conduit that will carry the DC and AC from the roof to the East Mechanical room.  No problem.  The installation team used a shop vacuum to pull a nylon string attached to a small plastic ‘balloon’ through the conduit.  Within minutes, the fish tape was then in place.

At the end of the day, Don Henderson, the senior person on the installation team, called for an inspection for Monday afternoon with the City of Monte Sereno.  After ensuring the site was clean and secure, Don called it a week.

Backfilling and Compacting the Trench for Natural Gas and Electricity

Izzy completed the backfilling and compacting of our trench this afternoon.  Completing the backfilling created a significant amount of real estate at the front of the property.  Also, it made the site much safer and easier to get around.  Izzy’s next task was to put the 4 inch pipe in place around the perimeter of the house that will take 100% of the water from the roof to our underground cistern.  He got a good start on this today and will finish it by Wednesday.

Connecting the Ground Loops

Justin and Michael from 88HVAC were on site again today.  They connected two ground loops in each concrete pier on the West side of the house.  Next week they will test the ground loops in each concrete pier for adequate flow and pressure.  If that test is OK, then they will connect the concrete piers and bring the complete ground loop inside the house to the West Mechanical room.

Overall, we’re continuing to make progress.  And progress is good.

Starting to lay out where the mounts will be located on the upper flat roof. The cool night resulting in very heavy condensation on the newly Tyveked roof.

Izzy was backfilling and compacting the trench for the natural gas and underground electric conduit.

The team from Akeena Solar installs the mounts on the upper flat roof. It was a beautiful, blue-sky California day (again).

The acorn nuts can now be covered with the tapered foam insulation such that the member will not be damaged over time.

Don Henderson, from Akeena Solar, in an animated telephone conversation on our upper flat roof.

Conduit that will take the AC lines from the North gable roof to the East Mechanical room.

Don reviews progress.

The solar mounts are looking good! The tapered insulation will cover the solar mounts.

Don Henderson calls it a day. And a week. The team from Akeena Solar will be back on Monday to finish the last items and then the City of Monte Sereno will inspect the progress on Monday afternoon.

Other than the location for the new electric service box, the trench with the natural gas and electric is backfilled and compacted. The pile of dirt is much smaller now!

After taking the flag down, Bryan smiled and took one last picture of the solar mounts on the upper flat roof.