In a recent post I wrote that an Electrician license alone – even a Master Electrician license – does not qualify you to design and install solar systems. I totally respect the fact that a Master license is a great achievement that requires significant experience and training, but it’s not solar specific. Some took exception to that position, but those are just the facts, in my opinion, and I think I have the experience and credentials to have that opinion.
Most states address this by requiring a building and an electrical permit to legally install a residential or commercial solar system. And in most cases, the plans have to be sealed by a licensed Professional Engineer.
But in many parts of West Virginia, as far as I can understand based on multiple inquiries to the Contractor Licensing Board, there are no clear licensing rules.
At Milestone, we have two licensed Master Electricians in our group, and I’ve worked with other Master Electricians as fill-ins, and I can tell you with total certainty that until you’ve received some formal training on solar systems, or on-the-job oversight from a trained and certified NABCEP installer, you’re not qualified to install all of the electrical components of a solar system, let alone design solar systems. There are many specific electrical issues that are quite unique to solar systems. And electrical is only part of the process. That’s not just my opinion. That’s according to NABCEP’s Job Task Analysis (JTA), spelling out in detail the areas their installer certification test covers and the percentage of questions for each area of expertise (Content Domain in the table below).Continue reading “What it takes to be a Qualified Solar Installer”
There’s only one reason I can think of why anybody would take on the serious safety and long-term production risks of having an inexperienced installation company, or one using a group of trainees, install their solar system. That reason is, they may not know what to ask about, besides price. And when safety and structural integrity are on the line, cheaper isn’t better.
Most non-micro solar systems operate at very high DC current flow and voltages (some as high as 1000 volts DC). Adding batteries takes the installation to a whole other level of complexity. The design and safety issues involved are real and not, in my opinion, a good place for a class project or on-the-job training at the homeowner’s peril.
And while a master electrician license requires knowledge and experience, the license alone doesn’t make someone truly qualified to design and install solar systems. There’s lots more to it than what’s covered in the National Electric Code book or the master test. (I’m sure of that because we have two master electricians on our team, and I’m very familiar with every edition of the NEC Book published since 2005.)
That’s only one part of a solar installation project – and the reason most authorities having jurisdiction (AHJs) require a building permit as well as an electrical permit.
So in addition to pricing, licenses and components, you should also ask potential installers about track record, references from previous projects, solar experience and certifications.
Probably the best question you can ask is whether someone who’ll be working on your installation has earned North American Board of Certified Energy Practitioners certifications. Their PV (PhotoVoltaic) Technical Sales and PV Installer certifications are tough to get. That’s because NABCEP is the only organization that tests for and credentials every aspect of grid-tied, off-grid and battery backup solar installations – design, mechanical issues, electrical issues, optimized production issues, installation and maintenance. (Please don’t confuse this with NABCEP’s Associate certification, which is an entry-level program; Associates must work under a senior installer, hopefully with full NABCEP certification.) You can check which, if any, NABCEP certifications an installer holds here.
Check out this glowing Angie’s List Review from a White Sulphur Springs, WV, customer on March 30, 2016:
Milestone Solar Consultants, owned and operated by Bill Anderson, did our install. We purposely waited 5 to 6 months before doing a review because new stuff always looks good in the beginning but what about months later? We wanted it before the winter set in and he made that happen. ALL his workers were polite, courteous and knowledgeable about what they were doing. We had the batteries and analyzers placed in our basement. There were no boxes, wiring or any trash left lying around anywhere. They even swept. They left my house better than they found it. Mr. Anderson promised a turnkey job and that’s exactly what we got. All the wiring from the outside mounting racks to the basement equipment looks like a piece of art. Their attention to even the smallest detail is second to none! Even though they are a 4½ hour drive fro us, anytime we called him Mr. Anderson made himself available to us and was ready to drive down immediately to address any concerns or issues we had even if they turned out to be unwarranted. This shows his dedication to what he is doing, and he will do whatever is needed to see both his solar system and his customer is always happy. We’ve already experienced 3 power outages with our Electric Company and didn’t even know it. The solar system’s batteries kicked in so efficiently and quickly that our digital clocks didn’t even start blinking. When the power comes back on the batteries switch back to standby without us having to do a thing. We also ran our home on just the solar system itself, going completely off the grid (in the winter) and ran everything easily for 4 or 5 days. Which is exactly what Mr. Anderson said it would do. He has the credentials and expertise to answer any questions you pose to him. None of that, “Well I don’t know. I will have to check on that question and get back to you.” Which we had with other big name solar installers. Milestone Solar came into our home as strangers and left as family. Any and ALL questions were answered by Mr. Anderson and his crew and there were a lot of them! And we know he will ALWAYS be just a phone call away if we have more questions or need him in any way. And that speaks volumes!! If you are looking to put in a Solar Array System, it would be to your advantage to have a quote from Milestone Solar. His prices can’t be beat ESPECIALLY when he uses ONLY top quality equipment and materials. We looked at many different systems from other companies but Milestone Solar stood out by miles…no pun intended 🙂
When we first started Milestone Solar, a residential solar system that featured a battery backup option was not at all common. It was mostly a cost issue, as the batteries do add substantial cost to the system. But I think it was also true that many installers did not (and probably still do not) like the extra complexity that an integrated battery backup (bimodal) capability brings to the project, so they did not promote the capability.
We’ve always liked the bimodal technology and the capabilities it brings, and have offered it as an option to customers for years now. Our installed base of battery backup systems speaks for itself.
But there are thousands of residential solar systems that were installed without batteries. This type of system, which I call a straight production system, does a great job of producing electricity on a day-to-day basis, but when the grid is down, your solar system shuts down – by design. One of my friends, an engineer in the solar industry, calls it buyer’s remorse to discover that you now want to add battery backup to your legacy solar system.
Over the past few years we have been hearing more and more about a capability to retrofit legacy solar systems with batteries using an electrical design called AC Coupling. Our standard or typical bimodal battery backup system uses DC coupling and features the array, charge controller, batteries, inverter and critical loads subpanels. Everything on the input side of the inverter is DC.
As you can see on the graphic at the top from Enphase Energy, the main components in this AC Coupling design/ retrofit are the battery bank, a compatible inverter/charger and a critical loads subpanel. On a day-to-day basis the solar array and, in this example, micro inverters, are sending AC power to the critical loads panel. Any excess is sent on to the new inverter/charger to be routed to the main panel for use in the house, or sent back to the grid for credit via the bidirectional meter. But when the grid is down, the inverter/charger begins supplying power from the battery bank, and after a short pause, the micro inverters will see a 240 VAC connection and will once again begin producing electricity.
One of the keys to this process is to have a fully compatible inverter/charger that is monitoring the state of the battery bank to insure that the batteries are protected from overcharging. Most use a process called “frequency shifting” to take the AC connection to the solar system out of spec, shutting down the array inverter(s) when the batteries are at a certain state of charge. Some companies are also recommending an additional inline relay to further protect the batteries from overcharging – an option worth looking into as well.
The obvious question that comes up now is, should we now abandon DC coupling for this AC-coupled configuration? In my opinion, if you are starting from the beginning, the DC coupled system design offers significant advantages, like highly efficient MPPT charge controllers with a tapered charge cycle that can be “tuned” to your individual system and also provides great battery protection.
It probably goes without saying that this is not a good do-it-yourself project for the average homeowner. But there is now more than enough of an installed base to consider AC coupling a viable and fully supported option for the many customers with legacy solar systems who would like to add batteries for when the grid is down.
In his book, Lights Out, veteran newsman Ted Koppel says blackouts could happen anywhere and everywhere..
In 2003, Koppel wrote, when “a high-voltage power line in northern Ohio brushed against some trees and shut down…fifty million people lost power for up to two days in an area that spanned southeastern Canada and eight northeastern states.”
In 2014, when two terrorists with AK-47 rifles shot up a substation near San Jose, California, it took 27 days to restore power to Silicon Valley.
Tomorrow, says Koppel, one hostile hacker armed with nothing more lethal than a laptop could take down“three power grids that generate and distribute electricity throughout the United States,” plunging “millions of Americans into…something approximating the mid-nineteenth century.”
Months without light, heating or cooling. Months with food rotting in refrigerators and freezers. Months with stoves that can’t cook, toilets that can’t flush, washing machines that can’t wash.
That’s because, according to Lights Out, our power generation and distribution system suffers from three major vulnerabilities.
The first is that
electricity flowing throughout the United States depends absolutely on computerized systems designed to maintain perfect balance between supply and demand…It is the Internet that provides the instant access to the computerized systems that maintain that equilibrium. If a sophisticated hacker gained access to one of those systems and succeeded in throwing that precarious balance out of kilter, the consequences would be devastating. We can take limited comfort in the knowledge that such an attack would require painstaking preparation and a highly sophisticated understanding of how the system works and where its vulnerabilities lie. Less reassuring is the knowledge that several nations already have that expertise…As the ranks of capable actors grow, the bar for cyber aggression is lowered.
The second is a physical, not cyber, threat.
The nature of the electric power industry is such that it combines modern technology with antiquated equipment. Some of that equipment is so large, so expensive, and so difficult to replace that it constitutes an entire category of vulnerability…No country in the world has a larger base of installed large power transformers than the United States, and that base is aging…on average, thirty-eight to forty years old…Conservatively, there are thousands of aging transformers, most custom-built, unable to be ordered from a catalogue or mass-produced, each costing somewhere in the neighborhood of $3 million to $10 million…[and] so large they cannot be transported on a standard railroad freight car.
If saboteurs with high-powered rifles were to knock out large power transformers in nine critical substations – like the one in San Jose – “it could cause a blackout encompassing most of the United States.”
And that’s because of the third vulnerability, the cascade effect. As cyberattacked or sabotaged equipment starts to fail, the electric grid’s harder and harder tries to compensate cause more failures. “Overburdened lines fall like dominoes.”
When and if this happens, says the Department of Homeland Security, you should keep a battery-powered radio handy. We have a better idea: a battery-powered house.
Not just for days (and nights, thanks to the batteries), not just for weeks and months, but for as long as the sun rises each morning.
Unlike emergency backup generators, there’s no danger of toxic exhaust fumes, no moving parts to wear out, and no chance of fuel running out before the lights come back on; a Milestone Solar system with battery backup “refuels” with each sunrise.