The internet is a compelling tool. While the satire in this example is deliberate, other more insidious sources deliberately deceive to sway public opinion. Many have deep pockets too because they represent powerful people with focused agendas.
Sometimes I wonder if this is in some way responsible for the extreme polarization of American society today. From congressional blame to climate change, from evolution to intelligent design, its so very easy these days to spin up talking points with supporting factual data and publish to the masses.
There are some who believe that reality itself is simply the mass opinion of the majority. Perhaps this is true. Back in the day, we Americans had such a singular awareness of our common reality that we could do great things. We built the Interstate system and the Panama Canal. We brought equality to our citizens. We walked on the moon.
Today, we are so polarized that we can’t even pass a budget. A grand project such as the Interstate would be impossible given today’s fractured view of reality. We are running on autopilot because we have been so successfully splintered that we can’t collectively turn the ship any more. We are pawns.
We received this letter from Elon Musk in our inbox yesterday.
October 4, 2013
About the Model S fire
By Elon Musk, Chairman, Product Architect & CEO
Earlier this week, a Model S traveling at highway speed struck a large metal object, causing significant damage to the vehicle. A curved section that fell off a semi-trailer was recovered from the roadway near where the accident occurred and, according to the road crew that was on the scene, appears to be the culprit. The geometry of the object caused a powerful lever action as it went under the car, punching upward and impaling the Model S with a peak force on the order of 25 tons. Only a force of this magnitude would be strong enough to punch a 3 inch diameter hole through the quarter inch armor plate protecting the base of the vehicle.The Model S owner was nonetheless able to exit the highway as instructed by the onboard alert system, bring the car to a stop and depart the vehicle without injury. A fire caused by the impact began in the front battery module – the battery pack has a total of 16 modules – but was contained to the front section of the car by internal firewalls within the pack. Vents built into the battery pack directed the flames down towards the road and away from the vehicle.When the fire department arrived, they observed standard procedure, which was to gain access to the source of the fire by puncturing holes in the top of the battery’s protective metal plate and applying water. For the Model S lithium-ion battery, it was correct to apply water (vs. dry chemical extinguisher), but not to puncture the metal firewall, as the newly created holes allowed the flames to then vent upwards into the front trunk section of the Model S. Nonetheless, a combination of water followed by dry chemical extinguisher quickly brought the fire to an end.
It is important to note that the fire in the battery was contained to a small section near the front by the internal firewalls built into the pack structure. At no point did fire enter the passenger compartment.
Had a conventional gasoline car encountered the same object on the highway, the result could have been far worse. A typical gasoline car only has a thin metal sheet protecting the underbody, leaving it vulnerable to destruction of the fuel supply lines or fuel tank, which causes a pool of gasoline to form and often burn the entire car to the ground. In contrast, the combustion energy of our battery pack is only about 10% of the energy contained in a gasoline tank and is divided into 16 modules with firewalls in between. As a consequence, the effective combustion potential is only about 1% that of the fuel in a comparable gasoline sedan.
The nationwide driving statistics make this very clear: there are 150,000 car fires per year according to the National Fire Protection Association, and Americans drive about 3 trillion miles per year according to the Department of Transportation. That equates to 1 vehicle fire for every 20 million miles driven, compared to 1 fire in over 100 million miles for Tesla. This means you are 5 times more likely to experience a fire in a conventional gasoline car than a Tesla!
For consumers concerned about fire risk, there should be absolutely zero doubt that it is safer to power a car with a battery than a large tank of highly flammable liquid.
Below is our email correspondence with the Model S owner that experienced the fire, reprinted with his permission:From: robert Carlson
Sent: Thursday, October 03, 2013 12:53 PM
To: Jerome Guillen
Subject: carlson 0389Mr. Guillen,Thanks for the support. I completely agree with the assessment to date. I guess you can test for everything, but some other celestial bullet comes along and challenges your design. I agree that the car performed very well under such an extreme test. The batteries went through a controlled burn which the internet images really exaggerates. Anyway, I am still a big fan of your car and look forward to getting back into one. Justin offered a white loaner–thanks. I am also an investor and have to say that the response I am observing is really supportive of the future for electric vehicles. I was thinking this was bound to happen, just not to me. But now it is out there and probably gets a sigh of relief as a test and risk issue-this “doomsday” event has now been tested, and the design and engineering works.rob carlson
On Oct 3, 2013, at 12:29 PM, Jerome Guillen wrote:Dear Mr. Carlson:I am the VP of sales and service for Tesla, reporting directly to Elon Musk, Tesla’s CEO.
I am sorry to hear that you experienced a collision in your Model S 2 days ago. We are happy that the Model S performed in such a way that you were not injured in the accident and that nobody else was hurt.
I believe you have been in contact with Justin Samson, our service manager, since the accident. We are following this case extremely closely and we have sent a team of experts to review your vehicle. All indications are that your Model S drove over large, oddly-shaped metal object which impacted the leading edge of the vehicle’s undercarriage and rotated into the underside of the vehicle (“pole vault” effect). This is a highly uncommon occurrence.
Based on our review thus far, we believe that the Model S performed as designed by limiting the resulting fire to the affected zones only. Given the significant intensity of the impact, which managed to pierce the 1/4 inch bottom plate (something that is extremely hard to do), the Model S energy containment functions operated correctly. In particular, the top cover of the battery provided a strong barrier and there was no apparent propagation of the fire into the cabin. This ensured cabin integrity and occupant safety, which remains our most important goal.
We very much appreciate your support, patience and understanding while we proceed with the investigation. Justin keeps me closely informed. Please feel free to contact me directly, if you have any question or concern.
Jerome Guillen I VP, WW sales and service
Yesterday we took this car for a spin. Its a Tesla Model S with the 85K+ performance package and all the toys you’d expect in a luxury automobile. I’m a tough customer too since I’m used to the performance, luxury, and handling of my BMW 5 series.
Well, after the test drive all I can say is this: Wow, what a car!
Brain dump follows:
Everything you ever thought about cars is dead. This is a whole new paradigm. The model S performs like a BMW E39 M5 but acceleration is constant across the entire speed range. This car darts.
The doors don’t even have locks… The map display is the size of a road atlas. No noise except tires. No engine to shut off so you just leave when you are done & it does the rest. Conversely, as you approach the door handles pop out and the climate system engages. When you sit down in the driver’s seat, automotive systems light up. Too cool!
It’ll cost us 800-1000 a month more than we spend on our cars now but in 3 years Tesla will buy it back for more than the remaining amount on the loan. Guaranteed. Its an investment!
The down payment is mostly covered by the Federal tax rebate.
Here’s a clip showing Angel getting some experience with regenerative braking…
Here’s a few more shots. Look at the size of the full map display! I have an old Rand McNally atlas that’s about that same size…
Another shot of the display, this time showing the backup camera. There isn’t a knob or a button to be found in a Tesla except where you expect to find them.
Everything in this car makes sense. There’s a little stick on the right side of the wheel. Push up for drive, down for reverse. Tap for park. Left side has familiar lighting and cruise control sticks. On the left door are the mirror/window controls right where you expect them to be. The display is so big that its easy to see and use the touch screen controls. In fact, in the image above you can see the climate system controls below the backup cam view.
Here’s what’s really cool: our 4KW solar array is designed to power this zero emissions car for over 14,000 miles a year. Our Tesla will be powered by the sun!
Monitoring array output is pretty simple with my TED5000. Once I extended the computer room circuit up to the attic, I installed a new MTU, clamped the circuit taps around the array hot wires and registered everything using the web interface. The results were instantaneous:
TED was now showing Net energy usage and I could easily switch between Demand (MTU 1), and Generation (MTU 2).
Historical results began updating right away too. Here’s the minute graph:
Green is my energy usage and dark blue is my net energy usage. The aqua blue line represents power from the array. Not too bad for two mostly cloudy days! Here’s the monthly plot:
Data is stored historically by month as well so I should be able to build up a pretty good picture over time.
Of course, I have mobile monitoring capabilities too using an excellent app called EnergyViewer for TED5000 by BCS Software.
This cool little app allows me to see pretty much everything the TED website shows.
All in all a pretty good deal to at $.99. There’s a tablet version too which adds multiple power graphing and historical displays to take advantage of a tablet’s larger size.
It does require that you map your TED5000 gateway to the internet however, but I prefer this to using a cloud based provider.
I’m currently debating whether I’ll also begin using Enphase Envoy which can give me detailed statistics by solar panel. At $500 – $600 however, I may be considering this for quite some time….
I ran across this one while randomly surfing yesterday and I must say that its content couldn’t be more timely. Distributed Solar installations such as the one I’m building have the potential to change the very nature of energy distribution as we know it. The utilities have held this monopoly since electricity’s introduction in the early 1900s and they are worried. To this effect, the EEI which represents the combined electrical utilities created a white paper back in January. Their bottom line is that net metering tariffs are a bad thing for the current utility investment model and that Distributed Energy Resource (DER) providers along with Energy Efficiency (EE)/demand side management (DSM) adopters should also be required to pre-pay long term capital purchases (such as power plant investments) or even pay a penalty to recoup those same investments if they go entirely off-grid. Otherwise, the EEI contends that remaining customers would be forced to pay ever larger tariffs to support the current distribution strategy, leading to a vicious cycle of customer desertion/tariff hikes whose final result would be the complete collapse of the traditional monopolistic model itself.
Never mind that similar investment strategies in more modern infrastructures with far faster ROIs (such as regional battery or flywheel systems that store DER power for non-peak distribution) would be something that benefits all customers.
The phone company and the airline industry are cited as prime examples of corporations whose once solid investment models were shattered. Never mind that both of the above examples adapted their strategic focus to create a boom in their respective industries. Furthermore, Telecom industry strategic change pressure resulted in a technological revolution that itself changed the very way we acquire and process content.
Why isn’t the EEI seeing this same opportunity in the brave new world of renewable energy production? Because it threatens their investors’ way of life, that’s why.
Anyway, here’s David Roberts’ take. To read the below referenced EEI paper for yourself, follow this link
Source: The Grist
Publication Date: April 10th 2013
By: David Roberts
Solar power and other distributed renewable energy technologies could lay waste to U.S. power utilities and burn the utility business model, which has remained virtually unchanged for a century, to the ground.
That is not wild-eyed hippie talk. It is the assessment of the utilities themselves.
Back in January, the Edison Electric Institute — the (typically stodgy and backward-looking) trade group of U.S. investor-owned utilities — released a report [PDF] that, as far as I can tell, went almost entirely without notice in the press. That’s a shame. It is one of the most prescient and brutally frank things I’ve ever read about the power sector. It is a rare thing to hear an industry tell the tale of its own incipient obsolescence.
I’ve been thinking about how to convey to you, normal people with healthy social lives and no time to ponder the byzantine nature of the power industry, just what a big deal the coming changes are. They are nothing short of revolutionary … but rather difficult to explain without jargon.
So, just a bit of background. You probably know that electricity is provided by utilities. Some utilities both generate electricity at power plants and provide it to customers over power lines. They are “regulated monopolies,” which means they have sole responsibility for providing power in their service areas. Some utilities have gone through deregulation; in that case, power generation is split off into its own business, while the utility’s job is to purchase power on competitive markets and provide it to customers over the grid it manages.
This complexity makes it difficult to generalize about utilities … or to discuss them without putting people to sleep. But the main thing to know is that the utility business model relies on selling power. That’s how they make their money. Here’s how it works: A utility makes a case to a public utility commission (PUC), saying “we will need to satisfy this level of demand from consumers, which means we’ll need to generate (or purchase) this much power, which means we’ll need to charge these rates.” If the PUC finds the case persuasive, it approves the rates and guarantees the utility a reasonable return on its investments in power and grid upkeep.
Thrilling, I know. The thing to remember is that it is in a utility’s financial interest to generate (or buy) and deliver as much power as possible. The higher the demand, the higher the investments, the higher the utility shareholder profits. In short, all things being equal, utilities want to sell more power. (All things are occasionally not equal, but we’ll leave those complications aside for now.)
Now, into this cozy business model enters cheap distributed solar PV, which eats away at it like acid.
First, the power generated by solar panels on residential or commercial roofs is not utility-owned or utility-purchased. From the utility’s point of view, every kilowatt-hour of rooftop solar looks like a kilowatt-hour of reduced demand for the utility’s product. Not something any business enjoys. (This is the same reason utilities are instinctively hostile to energy efficiency and demand response programs, and why they must be compelled by regulations or subsidies to create them. Utilities don’t like reduced demand!)
It’s worse than that, though. Solar power peaks at midday, which means it is strongest close to the point of highest electricity use — “peak load.” Problem is, providing power to meet peak load is where utilities make a huge chunk of their money. Peak power is the most expensive power. So when solar panels provide peak power, they aren’t just reducing demand, they’re reducing demand for the utilities’ most valuable product.
But wait. Renewables are limited by the fact they are intermittent, right? “The sun doesn’t always shine,” etc. Customers will still have to rely on grid power for the most part. Right?
This is a widely held article of faith, but EEI (of all places!) puts it to rest. (In this and all quotes that follow, “DER” means distributed energy resources, which for the most part means solar PV.)
Due to the variable nature of renewable DER, there is a perception that customers will always need to remain on the grid. While we would expect customers to remain on the grid until a fully viable and economic distributed non-variable resource is available, one can imagine a day when battery storage technology or micro turbines could allow customers to be electric grid independent. To put this into perspective, who would have believed 10 years ago that traditional wire line telephone customers could economically “cut the cord?” [Emphasis mine.]
Indeed! Just the other day, Duke Energy CEO Jim Rogers said, “If the cost of solar panels keeps coming down, installation costs come down and if they combine solar with battery technology and a power management system, then we have someone just using [the grid] for backup.” What happens if a whole bunch of customers start generating their own power and using the grid merely as backup? The EEI report warns of “irreparable damages to revenues and growth prospects” of utilities.
Utility investors are accustomed to large, long-term, reliable investments with a 30-year cost recovery — fossil fuel plants, basically. The cost of those investments, along with investments in grid maintenance and reliability, are spread by utilities across all ratepayers in a service area. What happens if a bunch of those ratepayers start reducing their demand or opting out of the grid entirely? Well, the same investments must now be spread over a smaller group of ratepayers. In other words: higher rates for those who haven’t switched to solar.
That’s how it starts. These two paragraphs from the EEI report are a remarkable description of the path to obsolescence faced by the industry:
The financial implications of these threats are fairly evident. Start with the increased cost of supporting a network capable of managing and integrating distributed generation sources. Next, under most rate structures, add the decline in revenues attributed to revenues lost from sales foregone. These forces lead to increased revenues required from remaining customers … and sought through rate increases. The result of higher electricity prices and competitive threats will encourage a higher rate of DER additions, or will promote greater use of efficiency or demand-side solutions.
Increased uncertainty and risk will not be welcomed by investors, who will seek a higher return on investment and force defensive-minded investors to reduce exposure to the sector. These competitive and financial risks would likely erode credit quality. The decline in credit quality will lead to a higher cost of capital, putting further pressure on customer rates. Ultimately, capital availability will be reduced, and this will affect future investment plans. The cycle of decline has been previously witnessed in technology-disrupted sectors (such as telecommunications) and other deregulated industries (airlines).
Did you follow that? As ratepayers opt for solar panels (and other distributed energy resources like micro-turbines, batteries, smart appliances, etc.), it raises costs on other ratepayers and hurts the utility’s credit rating. As rates rise on other ratepayers, the attractiveness of solar increases, so more opt for it. Thus costs on remaining ratepayers are even further increased, the utility’s credit even further damaged. It’s a vicious, self-reinforcing cycle:
One implication of all this — a poorly understood implication — is that rooftop solar fucks up the utility model even at relatively low penetrations, because it goes straight at utilities’ main profit centers. (It’s already happening in Germany.) Right now, distributed solar PV is a relatively tiny slice of U.S. electricity, less than 1 percent. For that reason, utility investors aren’t paying much attention. “Despite the risks that a rapidly growing level of DER penetration and other disruptive challenges may impose,” EEI writes, “they are not currently being discussed by the investment community and factored into the valuation calculus reflected in the capital markets.” But that 1 percent is concentrated in a small handful of utility districts, so trouble, at least for that first set of utilities, is just over the horizon. Utility investors are sleepwalking into a maelstrom.
(“Despite all the talk about investors assessing the future in their investment evaluations,” the report notes dryly, “it is often not until revenue declines are reported that investors realize that the viability of the business is in question.” In other words, investors aren’t that smart and rational financial markets are a myth.)
Bloomberg Energy Finance forecasts 22 percent compound annual growth in all solar PV, which means that by 2020 distributed solar (which will account for about 15 percent of total PV) could reach up to 10 percent of load in certain areas. If that happens, well:
Assuming a decline in load, and possibly customers served, of 10 percent due to DER with full subsidization of DER participants, the average impact on base electricity prices for non-DER participants will be a 20 percent or more increase in rates, and the ongoing rate of growth in electricity prices will double for non-DER participants (before accounting for the impact of the increased cost of serving distributed resources).
So rates would rise by 20 percent for those without solar panels. Can you imagine the political shitstorm that would create? (There are reasons to think EEI is exaggerating this effect, but we’ll get into that in the next post.)
If nothing is done to check these trends, the U.S. electric utility as we know it could be utterly upended. The report compares utilities’ possible future to the experience of the airlines during deregulation or to the big monopoly phone companies when faced with upstart cellular technologies. In case the point wasn’t made, the report also analogizes utilities to the U.S. Postal Service, Kodak, and RIM, the maker of Blackberry devices. These are not meant to be flattering comparisons.
Remember, too, that these utilities are not Google or Facebook. They are not accustomed to a state of constant market turmoil and reinvention. This is a venerable old boys network, working very comfortably within a business model that has been around, virtually unchanged, for a century. A friggin’ century, more or less without innovation, and now they’re supposed to scramble and be all hip and new-age? Unlikely.
So what’s to be done? You won’t be surprised to hear that EEI’s prescription is mainly focused on preserving utilities and their familiar business model. But is that the best thing for electricity consumers? Is that the best thing for the climate?
The array was commissioned without a hitch last Friday. It was a fairly simple process too. Essentially, the WE Energies engineer had me switch on the disconnect then he waited for the meter to register energy production. After five minutes, the array went into energy production mode and they saw what they were looking for. Since the inverters themselves conform to UL1741, anti-islanding was guaranteed and that’s all WE Energies needed to see. I signed the Distributed Generation Interconnection Agreement, everybody shook hands and they left.
Anti-climatic if you ask me.
Extend the TED monitoring branch circuit up to the 6x6x6 junction box in the attic then install a TED5000 CT there so I can begin tracking detailed energy production.
By the way, I checked the price for OPT-265 solar panels and they are down to $281. I paid $324 for ours. M-215 inverter prices are also dropping since a higher powered M-250 was introduced in August. We’re going to save quite a bit of money if this trend continues when we bring the remaining 3KW online next summer.
The inspector and my contractor showed up yesterday and the setup breezed through inspection. Having a parallel PV installation was key here since it split out the existing residential/expense side of my electrical installation from the new commercial/revenue side.
As it turns out, electricians and even New Berlin electrical inspectors themselves have separate residential and commercial groups. Because our 1kW array is a revenue earning installation, the inspector was from the commercial side of the house and his task was simply to evaluate the PV portion of our dual meter installation. Had we gone with a serial PV setup (where the solar array is connected directly to a breaker on the main panel), then both groups would have been involved at all points of the project. In this scenario, the same tasks could have taken twice as long to accomplish due to the additional level of coordination required. Parallel installations are definitely the way to go!
Our inspector was also quite impressed with the level of standardization on the roof. This was the first time he had inspected an Enphase M215 micro-inverter setup with engage trunk cable on standardized Renusol racking, and he quickly caught on to the implications. He even asked for cut sheets on the new inverter/racking technology for his personal records citing that this could “open the sluice gates” for home PV installations.
I couldn’t agree more.
So, what happens next?
The inspector will inform our WE Energies contact person that the configuration is ready to commission.
Somebody from WE Energies will be out before Friday to install the PV generation meter
WE energies will show up on the afternoon of 9/13 to commission the system. Essentially, they will turn everything on at the disconnect, verify that it powers up correctly then (most important part), turn it back off to make sure the inverters shut down within 2 minutes. This test proves out the system’s the anti-islanding capabilities.
Sometime in the future, a lineman will be out to replace the temporary splices at the service entrance weatherhead with their own. Interestingly, my contractor told me that it could be months before they got around to it. He also said to make sure they give back the current splices since they are apparently worth quite a few bucks on eBay…
On my immediate task list:
Install a second TED5000 CT in the 6″ attic box and connect up to my TED5000 system. This circuit tap will measure PV output and allow my TED to precisely track overall PV system performance over time. I’ve ordered this component already and it should arrive sometime next week.
Extend the computer room branch circuit up to the attic to provide connectivity to the TED CT. This will require BX armored cable and may be a bit of a pita since the cable itself will go up the chimney enclosure.
Purchase 2 DIN mounted SPs to protect the array against lightning surges as well as a new Panel mounted SP to protect my extensive UPB installation.
Fill out the Focus on Energy rebate form just as soon as I get the bill from my contractor. My deadline to accomplish this is October 10th.
My contractor has finished the array connections and a nicely done piece of work it is too! Here’s a few shots of the roof mounted junction box:
The box itself contains a DIN rail that can be used for surge protectors. I’ll install these when the other 12 panels go up. The other end of the half inch EMT conduit terminates on a Bell weather tight box under the panels. What’s nice about this is that I can simply extend the Enphase engage cable out to the next racks or I can choose to terminate more cables in the Bell junction box.
Here’s the completed disconnect:
My contractor also installed a 6″x6″x8″ box in the attic. The vertical conduit terminates there along with the 20′ horizontal run. Wires were pulled straight through this box then the hots were looped inside. This will be where my TED5000 circuit taps will connect. I’ll need to run BX from the computer room box up there myself to extend the TED signal carrying branch circuit (which is isolated from the rest of the house with an X10 filter).
I’ll do this after the array is commissioned.
We are almost generating power now! my next milestones are:
With the panels finally on site, it was time to get down to their actual installation. First, I needed to mock up the inverter/panel position to derive a measurement template. As it turned out, the inverters could be mounted directly below and at the midpoint of each panel, and the Engage cable coupler could be mounted directly above it. Taking the renusol inter-panel connectors into account, this made for 39″ between the bottoms of each panel, 25″ from the bottom of the panel to the inverter center, and 28″ from the bottom of the panel to the engage connector center. You can see the alignment in the pics below:
After I had the measurements, I marked them all out on the west rail with a blue sharpie. Then it was time to actually begin the assembly process itself.
My first installation step was to run the enagage trunk cable along the outside of the rail with connectors facing west. The idea behind this was that the 120v connector from each inverter would be run over the top of the west rail and left loose, to be connected up when the rest of the 120v wiring to the dual meter base is complete. The cable connectors’ west facing orientation would make them easily accessible once everything was ready.
Unfortunately, the cable was also incorrectly ordered for landscape, not portrait orientation so the distance between connectors was 67″ instead of 40″. This is why you can see that I’ve looped and wire-tied the excess to the rail. The wire-ties themselves were UV resistant and designed for outdoor use.
The first panel took the longest because it needed to be correctly aligned to perpendicular and centered on the rails. After that, it went pretty fast because each subsequent panel was simply aligned to the panel underneath. Essentially the process became:
Mount the inverter using a WEEB-CCR grounding washer between it and the rail and torque to 12ft lbs.
Run the panel up to the roof and lay on the rails. We used two ladders for this so that Angel and I could go up together with the panel suspended between us.
Connect up the panel’s DC cables to the DC side of the inverter. This powered up the inverter.
Double check that the inverter status LED went to flashing red (not producing AC) after about 5 minutes. Since these are grid-tie inverters, they will not produce AC if they don’t sense an existing AC signal on the grid itself.
Center/torque the panel to the rails using renusol connectors
We used WEEB-CCR grounding washers for the hardware between the first and second panels and also between the third and fourth panels. Here’s what a WEEB-CCR looks like:
These sit right on the top of the rail between the rail itself and whatever hardware is being mounted on it. When torqued to spec, four sharpened nubs on each end of the WEEB dig into the mounted hardware on one side and the rail on the other side. This forms a solid ground connection that is impervious to weather related corrosion.
With our installation, 8 WEEB-CCRs were required to form a complete grounding solution: four for the inverters, and two sets of two between panels.
By 4PM, we were done!
At this point, the 1KW installation is almost complete! Our final task will be to connect up the AC side to the meter. Next up, my contractor will be in to complete this in the following order.
Install a disconnect switch by the meter
Run conduit up into the attic and connect it to a 6×6 junction box that is itself connected to the horizontal conduit run I did earlier. This box will contain the CTs for my TED5000 energy monitor and allow me to monitor electric production from the array.
Mount a junction box on the roof near the array. The one we will use will actually be flashed into the roof itself.
terminate the engage trunk cable on the west rail using a weatherproof junction box, then run 1/2″ EMT between it and the roof mounted box.
pull #10 wire from the disconnect to the roof box and connect up.
Plans are to complete this on Tuesday, 8/13 and Wednesday 8/14. When finished, we will be ready for inspection/commissioning! Stay tuned!
The weather was nice and cool last Sunday; perfect for working above the garage, so I installed the second Renusol rail. This one would be a bit trickier than the first because the rail itself landed between two rafters. To make sure the anchor points were sufficiently engineered to withstand roof wind/snow loading, 4×4 cross braces would
be used at each of the four anchor locations.
Here’s a shot of one. Simpson strong-tie SD structural screws were used on the hangers since swinging a hammer was virtually impossible in the confined space above the garage. These #10 screws are pretty awesome; With their self tapping ends, they go in with virtually no force at all. I’ll be using them everywhere in the future! Two lengths were needed: 1 -1/2 inch screws went into the face connections and 2 – 1/2 screws were used for the toe-in slots.
On the top of the roof, I first marked 40″ off from the middle of the right side top and bottom bracket mounts (40″ is about 1000mm which is the on center distance between panel mounting holes) then made tape marks. Next, I once again used the rail itself as a giant straight edge to line up the other two mount points. Then, I measured down from the top of the shingle directly above each mark to determine the mounting location. This ended up being 1 – 3/4″ to make the edge of the flashing about 1/4″ above the edge of the shingle underneath it.
In the photo above, you can see the flashing piece itself which illustrates the 1 – 3/4″ offset requirement.
Once marked, assembly proceeded pretty much identically for each mount point:
drill a small pilot hole and insert a coat hanger
locate the coat hanger below the roof and install the cross brace
back on the roof, widen the pilot hole to 1/4″ and extend to 3″ depth, then position the Ecofasten flashing.
Fill the 1/4″ pilot hole with roofing mastic and position the sealing plate and the “L” bracket.
Ratchet down a SPAX 3/8 x 5″ HCR lag (HCR is their high corrosion resistant coating) but leave loose.
Finally, position the rail on the L-brackets, double check that it is parallel to the right side rail, and torque to 140 inch/lbs. Finished!
Next up, my contractor and I do the following:
wire up the second meter slot, install a disconnect and complete the conduit run from the disconnect to my horizontal run in the attic.
Attach the roof mount junction box onto the roof itself and run conduit from there to the other end of my horizontal run in the attic
Then we wait for the solar panels to arrive and make final connections. Stay tuned!