Is your solar power system safe? How can you be sure?
We are receiving more and more inquiries about fixing solar power systems from folks whose system has stopped working and the original installer can no longer be found. Sometimes a violent act of nature prompts the need for our services, but all too often we are seeing shoddy work that has failed far too soon.
Case in point, we received a call from a true “rocket scientist” the other day who had a solar power system installed about seven years ago, but now he was having a problem. We learned that the system had been installed by an air conditioning company (you’ve seen their ads), and it had two SMA Sunny Boy 2800 inverters—now well out of warranty—and one of them was displaying the dreaded, ground fault error. Ground faults occur when a normally ungrounded, current-carrying conductor makes contact with something that is grounded, such as the frame of a solar module, the system racking or even the conduit itself. Ground faults can be dangerous and are often difficult to locate.
When the solar system owner contacted his installation company, they offered to replace his offline inverter—for $5,000! Of course, simply replacing the inverter was unlikely to do anything about the ground fault, and it was possible that there was nothing wrong with the inverter at all, apart from being out of warranty. But in any event, charging $5,000 to simply do a one-for-one inverter replacement was highway robbery, and the system owner was pretty annoyed by the time he got around to calling us. Since there was no way to properly diagnose the situation over the phone, we agreed to come out and take a look.
Sure enough, one of the inverters was working fine, but the other displayed a ground fault message. The system owner told us that there was a combiner box on the roof, so we headed there to try and figure out where the fault might be. Here’s what we found in that “combiner box":
This is so NOT a combiner box!
This is a junction box into which the folks who threw this system together crammed the wires coming from the strings, joined them together (without any fusing to protect the array, to say nothing of the house) and then routed them downstairs to the inverters.
Another problem—the wires coming into this non-combiner box are all THHN, which is fine for a conductor running in conduit, but is no good at all for conductors coming from solar modules in the array. The insulation here is simply not designed to hold up under years of exposure to sunlight.
This is simply ignorant, shoddy work that has no place in the solar industry. Sadly, this particular company has not gone out of business, though the world would be a better place if they had.
People can get hurt this way. Property can be destroyed this way.
And the solar industry can get a very bad reputation this way.
We broke the bad news to the system owner and explained that what was needed was to replace the box on the roof with a proper combiner box, replace the improper wiring with USE-2 wiring that is designed to last on a roof, and bring the system back online. We also suggested that given that his existing inverters were out of warranty, he might want to consider upgrading to a single, transformerless inverter that would provide a ten-year warranty, the possibility of online monitoring, and much greater efficiency. That was the path he decided to take.
We installed an Outback combiner and upgraded the wiring. In so doing we managed to bring some order out of the previous chaos, take a look:
Now each of the four strings is properly protected by a dedicated, touch-safe fuse, and there is proper stress relief on the USE-2 conductors entering the box from the array.
We also installed ground lugs on each of the rails—something the air conditioning guys hadn’t bothered to do—and we installed two end clamps that had somehow been overlooked when the install was done.
The cool, new SMA 5000TL inverter allowed us to add monitoring to the system, as well as SMA’s emergency power outlet that provides a nominal amount of power from the array, even if the grid fails. In the process we were able to clean up the wiring on the ground, get rid of those air conditioning disconnect switches and install a proper disconnect. Oh, and while we were at it, we even arranged to donate the old inverters to Habitat for Humanity, providing the system owner with a charitable tax deduction!
Most importantly, we were able to restore his confidence in the solar array on his home. And maybe, even a bit of confidence in the solar industry itself.
There are a number of take aways from this experience that we would like to stress:
UPDATE - As its very own Christmas present to EV drivers, on December 24, 2014, SCE announced that as of January 1, 2015 the TOU-D-TEV rate structure would be closed to new participants, and that all existing SCE residential customers on this rate schedule will be migrated to another residential rate following their next meter read date after February 1, 2015. No explanation for the change was provided. We will write more about this in the coming days. (H/T Joseph Gray.)
SCE has devised an extremely complicated rate structure designed for residential customers who drive electric vehicles. Instead of having a separate meter for EV charging, this rate structure is designed to replace the Domestic rate and apply to the entire household’s energy use—presumably at a savings. But does it? What we discovered may come as a shock…
SCE has long offered a rate structure that was designed for separate meter charging of EVs. But as more and more people acquire EVs there were relatively fewer consumers looking to go through the hassle of installing a separate meter just to charge their EV. SCE’s combined household and EV charging rate, known by the unmelodious monicker of TOU-D-TEV ("EV Rate,” for short), is designed to provide a lower-cost option for customers who were previously on SCE’s standard, Domestic rate structure.
As the acronym implies, the EV Rate is a time-of-use rate structure which means that what you pay for a kilowatt-hour of energy is directly tied to when you use it. There are three time classes: On-Peak (weekdays, excluding designated holidays, from 10 a.m. to 6 p.m.), Super Off-Peak (everyday, midnight to 6 a.m.) and Off-Peak (all other times). In addition to the time of use component, the EV Rate includes tiers. While Domestic rate customers are used to four tiers at which energy gets progressively more expensive, the EV Rate has only two tiers. Put this all together and you have the potential to pay wildly different amounts for your energy, as this table shows:
Stay within Level 1 and use your energy during Super Off-Peak and you pay just 9.4¢/kWh. But make the mistake of using energy during the middle of the day in the summer in Level 2 and you will be pay a shocking, 46.4¢/kWh! Yikes!!! Sure hope you aren’t at home during the day running your A/C.
EV owners are not required to take service under the EV Rate structure (at least not yet), so why switch? SCE advises customers that they can save money using this rate and we wanted to see if that was really true. We decided to model two different users and see how their bills would change between the Domestic rate and the EV Rate. The first user, our “average” user, consumes roughly 1,000 kWh per month (probably on the low end for most EV owners), or a little more than twice the baseline allocation. The second user, our “large” user, consumes more like 2,500 kWh per month and reflects a large home with heavy A/C use.
Let’s start with the average user:
This graph compares what our average user would have paid under SCE’s Domestic rate (the constant, orange line) against what she would pay under the EV Rate (the blue line) as a function of what percentage of the total monthly usage occurs during On-Peak hours. (Throughout we assume that 20% occurs during the Super Off-Peak hours of midnight to 6 a.m., and the balance occurs during Off-Peak).
Under the Domestic rate, our average customer would pay $3,200 for the year. If she manages to keep her On-Peak usage down below 30% of the total energy consumption, she will save money—as much as $355 or 11% off her bill, if her On-Peak usage is jut 5%.
But those “savings” can quickly disappear if she isn’t careful (or her children aren’t). Let her On-Peak usage climb to 60% of her bill and she will get hit with a 12% penalty and end up paying $388 more than if she had not switched.
What about our “large” user, how does he fare?
Most likely, better.
While his overall bill is much higher—he would be paying $8,500 on the Domestic rate—his potential savings versus penalty comparison is much more forgiving. He can save as much as 13% ($1,100) compared to a penalty of only 6% ($478). Plus, his breakeven point is higher, as he doesn’t start losing money until his On-Peak usage gets to 45%.
(This actually continues a trend with SCE’s residential rates where increases are highest at the lowest end of usage and the very highest users are actually getting a bit of a break. What an odd sort of mixed message.)
Bottom line—it is possible to save money, even significant money, if you are very careful about when you use energy.
Most EV’s are designed so that you can program them to charge during off-hours and anyone under this rate structure would absolutely want to insure that they use that feature. Indeed, there may be other energy users that could be similarly re-programmed such as pool pumps, dishwashers and washing machines, to run during the Super Off-Peak window. Unfortunately, it is very difficult to avoid running your A/C during the day if anyone is at home from 10 a.m. to 6 p.m. on weekdays—and doing so could be very expensive.
It should be obvious, but adding solar to the mix here could be huge since On-Peak hours directly coincide with the greatest production from a solar power system. Put most simply, if you own an EV and are considering making the switch to this EV rate structure, you need solar.
It took way longer than we had hoped, but last year the Obama Administration fulfilled a promise to return solar to the White House and now they have a video to prove it!
Solar was first placed on the White House by President Jimmy Carter as a symbol of what was to come. Unfortunately, the next President reversed course and removed the solar panels. When Barack Obama was elected, the solar community began to agitate for solar to make a triumphant return to “the People’s House." It took quite awhile, but now we have the proof—check it out:
While this system is too small to offset more than a token amount of the energy needed by the White House, most homes or businesses can do far better. Whether its Your House or the White House, solar is here to stay. Finally.
We have long held that adding solar is a very conservative thing to do—as in conserving your money to say nothing about conserving the planet. A recent Op-Ed in the LA Times echoed that sentiment quite clearly just the other day and it is worth a mention.
Titled, “Koch brothers and big utilities campaign to unplug solar power,” the piece by David Horsey lays out quite clearly the cynical attempt by the Koch brothers (who have inherited one of the largest family owned corporations in the oil and gas industry and in so doing, are richer than God), investor owned utilities and the American Legislative Council (see, Not so smart ALEC), to roll back laws in red states that help promote the solar industry. Those laws—specifically renewable portfolio standards (known as an RPS, that mandates a percentage of renewable energy in a utility’s energy mix) and net metering—were readily adopted across the country when solar was still too expensive for most consumers. But the recent, precipitous price drops in solar power systems has awakened the sleeping giant of the fossil-fuel industry and now they mean business.
Apparently they scored a recent victory in Oklahoma with the governor there signing a repeal law for that state’s RPS. Score one for the Kochs.
But, as we have noted before, there are conservative groups who see this issue through a—dare we say it—more conservative lens. From the Op-Ed:
Environmentalists have been energized to stand in the way of this well-funded multi-state onslaught against solar power, and it is gratifying to hear there is one conservative with a venerable Republican lineage who is taking their side. Former California congressman Barry Goldwater Jr. has formed a group, awkwardly named Tell Utilities Solar won’t be Killed, that hopes to gather support among conservatives to oppose the big utilities.
“These solar companies are becoming popular, and utilities don’t like competition,” Goldwater told The Times. “I believe people ought to have a choice.”
Consumer choice. Business competition. Autonomy for individual Americans. Those certainly seem like sound conservative principles. You would think that is something the Koch brothers could appreciate, but, obviously, their brand of conservatism is defined less by principles than by profits.
Indeed those are sound principles that both conservatives and liberals can rally around.
The internal battle amongst conservatives is spilling over into the renewable energy arena, and how that battle plays out will determine whether conservation-minded conservatives can join forces with their enviro sisters and brothers, or if the only wearers of a conservative mantle will be following the scorched-earth policies of the Kochs.
Watch this space.
We are fans of SEIA, the Solar Energy Industry Association, as we believe that they do important work lobbying on behalf of solar in Washington, D.C. But a blog post by Chet Henry over at Red, Green & Blue titled, “Who has the best job in solar? Bet it’s not you,” (h/t SolarWakeup) had us spewing our coffee in disbelief—they are paying him what???
It turns out that SEIA is paying its President/CEO, Rhone Resch, $786,000 per year—to say nothing of a gym membership and guaranteed first class air travel. Say what?
Now this is not an attack on Mr. Resch, whom I respect. But seriously, SEIA, what the heck are you doing? Julia Hamm, who heads up SEPA, the Solar Electric Power Association (which tries to get electric utilities to adopt solar-friendly policies) gets paid roughly a third of Resch, at $286,000. Sorry, but there is no way Resch is worth three times what Hamm is. Worse still, according to the blog post, SEIA’s records reveal three other executive women at SEIA, none of whom makes more than a third of what Resch makes.
Frankly, we have been concerned for some time about SEIA’s dues structure which is disproportionately high for small revenue solar companies, and is one of the chief reasons that 80% of solar companies aren’t members. Indeed, we are no longer members as it simply didn’t seem like a worthwhile investment for our all too finite capital. Dumping nearly 800 G’s into one man’s salary, however, is no way to say to small installation companies, “we represent you and want you to participate.”
SEIA has noted that there are more than 140,000 people in this country working in the solar industry. I wonder how many of them are getting paid what SEIA is paying its President? SEIA has said that there are more than 5,000 solar companies in this country. I wonder how many of their President/CEOs are getting paid anywhere near what SEIA is paying its CEO?
I simply don’t buy the notion that you need to pay someone that kind of salary to attract the talent needed to do the job. After all, Ms. Hamm has to hobnob with the heads of IOUs who make 10 times as much as she does, but she can do it for nearly half a million dollars less than SEIA is paying out.
Time for reform at SEIA.