Solar Panel Installers & Consultants - West Virginia - Maryland - Pennsylvania - Virginia

SolarEdge’s StorEdge Inverter and the LG Battery System: Just the Facts

From residential to utility scale, storage is one of the biggest issues in the solar world. Technologies are evolving, and there will be many changes over the coming months and years

In our area, the recent big news seems to be the SolarEdge System – StorEdge Inverter coupled with the LG lithium-Ion battery. At least three solar companies in West Virginia are attempting to sell this system to solar consumers and, after multiple conversations with prospective buyers, I’m very sure many of the customers really don’t understand all the issues involved. I also suspect that in some cases, the installers also don’t understand what they’re attempting to sell. (For example, I asked an LG support tech about how the lithium-ion batteries would respond to being primarily storage for backup power instead of regularly cycled. His answer was “Guess I need to research that.” Good idea.)

Recently, a potential customer from a co-op, who’s considering a StorEdge/LG battery system, asked me for a competitive quote. When I told him we were not installing that system at this time for several reasons, he told me, “You guys need to come out of the Dark Ages, see the light; this is the technology of the future.”

Hmmmm. Really?

Interesting, particularly when you consider the fact we guys have installed more battery backup storage systems than anyone else in West Virginia.

But this did get me to take the time to really investigate the issues. Over several days I consulted with technical folks at SolarEdge, LG Batteries, and a customer support engineer at a leading solar distributor, who specializes in battery systems.

What follows are the facts as I understand them. I try to stay with the facts as best I can. There will also be some opinions, but those will be obvious.

The System

The system we’re talking about is the StorEdge system from SolarEdge. Currently, the only battery- capable SolarEdge inverter model is their 7600-watt model. This is basically the popular SolarEdge 7600 inverter with additional firmware, electronics and a transfer switch to allow it to interact with the battery system and a critical loads panel when the grid goes down.

The original release was designed to let StorEdge work with both the Tesla Powerwall and/or the LG 10 kWh battery system. The DC version of the Tesla PowerWall 2 system crashed and burned (not literally, as far as I know), leaving the LG battery system. This will currently work with only one LG battery; capability to tandem 2 batteries is supposed to be released soon. (That will be seriously expensive, however.)

The StorEdge system is designed to primarily work in one of two modes: The self-consumption mode, when the batteries engage on a regular basis to offset the need to buy from the utility. The system will also switch to backup mode when the grid is lost and a critical loads panel will be energized.

According to SolarEdge, the two typical applications for this consumption capability are:

  • Areas that don’t allow net metering (such as Hawaii and certain US co-ops). Solar power produced in excess to current loads is stored in batteries to be used later – at night, for example.
  • Areas with varied Time of Use rates. In this case, the system can be configured to supplement from the solar array’s production with battery input during certain time slots to avoid having to buy from the utility at the highest rate.

It’s very important to note that those two scenarios do not apply to our area, as long as we have one-for-one net metering. With net metering, this self-consumption capability is not a good choice for anyone. There are much better alternatives, like letting the grid store your excess PV production.

The other configuration is a straight backup configuration. In this case the batteries will engage only when the grid is lost. Then, an electronic transfer switch is engaged and the batteries energize the critical loads panel.

If you buy the StorEdge/LG system to use strictly as a backup power option, you’re not getting a good deal. In fact, I consider this system to be mediocre for a strictly backup only application based on:

  • Very high battery cost (compared to AGM storage)
  • Very limited stored capacity ( currently only 9.5 kWh useable)
  • Very limited surge capability. If you have a deep well, submerged well pump (3/4 HP or more), pay attention that that factor. Well pumps don’t react well to “brown power”.
  • Limited scalability (You’re restricted to the minimum and maximum solar array values that the 7600 inverter supports.) For larger arrays, you need a second inverter, which will not be part of the battery-based capability, by the way.
  • No integrated generator connection (for long grid outages)

The Data

This chart compares a StorEdge system with the LG battery to a Schneider XW5548 system with a 490 AH AGM battery bank. The XW5548 is their smallest model; we often install the XW6848 model, which is much more robust. The data points are taken directly from the companies’ published datasheets.

 SolarEdge StorEdge 7600 with LG 10 kWh BatterySchneider XW 5548 with 490 AH AGM Battery Bank
Max Continuous Output on Batteries5000W5500W
Surge Capacity – 30 secNot Available9500W
Surge Capacity – 10 sec7600W9500W
Switchover Time2 sec8 ms
Integrated Generator ConnectionNot AvailableYes
Useable kWh stored9.5 kWh (95 % DoD)17.6 kWh (75% DoD)
Cost (estimated retail), batteries only$6,100$4,000

Notes:

  • DoD = Depth of Discharge
  • The XW5548 is capable of surging to 7000 watts for up to 30 minutes at 25º C ambient temperature.

 

The cost information above is just for the batteries. If you were going with the 7600 StorEdge instead of a plain 7600, you’d also have to pay:

  • $1000 more for the StorEdge 7600 (versus a basic 7600 SolarEdge).
  • The cost of a step-down transformer to bring the LG battery’s high voltage down to a useable level.
  • For purchasing and installing miscellaneous electronics and hardware.

If you were simply adding an AC-coupled battery bank to a plain Solar Edge 7600, your additional costs would be for only:

  • An AC-coupled capable inverter/charger.
  • Battery enclosures. (The enclosures we install are metal.)
  • Miscellaneous electrical and hardware items and their installation.

Either way, you get much more bang for your buck buying a basic 7600 system and adding an AC-coupled battery bank. The AGM technology is rock-solar and predictable. The lithium-ion, not so much. (There’s a reason why the DC version of the Tesla Powerwall 2 was pulled from the market.)

During the tech boom in the years 2000-2002 I saw a lot of this. It’s the difference between leading edge and bleeding edge, the difference between deploying solid technologies and chasing evolving technologies. Over my more than 30 years in the tech business, and especially during almost 10 years at Cisco Systems, we did a lot of leading edge, early field trial stuff, but always in a very controlled environment. As a the owner of a small solar installation company I’m very sure our customers don’t want to put a lifetime of savings at risk just to have the newest widget, and I have no interest in asking them to. I will not be recommending any new technology before it’s been proven in the field over a considerable period of time.

Guess we’ll stay in the Dark Ages a while longer 🙂

As for why some solar companies are pushing this particular system, I don’t know. You’ll have to ask them.  

Solar Systems and Storage – What you need to know

If there’s more common buzzword in the solar industry today than storage, I don’t know what it would be. As is the case with many terms in the solar world, storage can mean different things – depending on who’s using it.

In its most basic use, storage means electric potential stored in a battery using a wide variety of chemistry, until presenting a load to the stored potential activates its power. For example, when you start your car, the electrical system presents a load to the battery, and the starter’s engaged.

When using the term storage within the discussion of solar energy it can get really confusing to the consumer. I tend to narrow it down to three typical applications (my terms) that actually exist at this point in time.

  1. Off-grid, when the batteries are the most fundamental part of the house electrical system. If the batteries are exhausted, you’ll either be in the dark or running off a generator system.
  2. Grid-tied with battery backup, where the battery bank mostly sits idle unless grid power is interrupted. Then the batteries engage, the inverter taking power from them and energizing a critical loads panel. You’re then operating as an off-grid system until grid power is restored – a two-mode (bimodal) system.
  3. Consumptive storage. This configuration is becoming very common in places like Hawaii and in many countries where electricity’s expensive and there’s no Net Metering (where the power company must accept all excess power from your array and credit you on a one-for-one kWh basis).

We’ve discussed off-grid systems on our website, so let’s look at systems 2 and 3 above.

A grid-tied, battery backup system (bimodal) is our favorite solar system, and I believe we’ve installed more of them than anyone in the region over the past 4 – 5 years. I know for a fact that we have dozens of systems installed and operational in the four-state region we serve.

As for the longevity of the batteries, we recently conducted a controlled load testing of a nearly 8-year-old AGM (Absorbent Glass Mat) battery system, and it showed almost no degradation of the battery bank. This test was conducted as part of an estate sale, and DEKA engineers confirmed our captured data. We’re expecting at least 10 years for the Made in USA, DEKA AGM batteries we use and have data to support that claim.

If properly and professionally designed and installed, bimodal systems provide years of trouble-free service and great peace of mind for the owners. In conjunction with an auxiliary generator system, they can provide the potential for months of electrical service in the event of a major loss of grid power. Some of our customers are preparing for this possibility.

A consumptive storage system is a different animal entirely. In this configuration, the solar array first services the house loads, then diverts excess power to be stored in batteries. When the array output doesn’t meet house loads (at night, for example) the batteries provide power to the house. One problem with this configuration is that it obviously demands batteries that can stand up to many cycles of charges and discharges (cycles). Another, really big, problem (to me) is that if the house loads are met, and the batteries are fully charged, the excess solar production is lost.

The consumptive solar system looks attractive to many, but the fact is that Net Metering, as long as we have it, is better by a wide margin.

If Net Metering goes away, then, like in Hawaii, consumptive storage will become the system of choice for many solar owners. We’re not there yet – and, by the way, neither are the battery systems needed to deliver a realistic return on investment or real work capability. If you don’t believe me, try to buy, and have delivered, one of the new Tesla Powerwall-2 DC systems. At some point other technologies like Lithium-Ion will probably be the answer, but not today.

By the way, the power companies are constantly challenging Net Metering – locally and throughout the country. I truly worry that if they influence enough politicians, Net Metering could be lost.

At this point, many of you may be wondering: If all this is true, why are some solar companies pushing customers to consider one of the latest and greatest storage systems based on cycling battery technologies, like lithium-Ion, instead of more mature and proven configurations like a bimodal system using AGM batteries.

The truth is I really don’t know for sure in every case, but I do know that potential solar consumers are being lobbied by solar salespersons with minimal or nonexistent battery system experience, understanding and credentials, and some customers are making some unfortunate purchase decisions.

Some of the battery system proposals we’ve been asked to review are both technically and economically incorrect – massively incorrect. Battery-based solar systems are substantially more complicated than typical grid-tied systems, and no place for on-the-job learning at your expense (and peril).

Do your own research. Ask for reference installs. Talk to existing system owners. Then, I invite you to give us a call or fill out a web page contact form for a free professional consultation and proposal.

“Plug-and-Play” isn’t

 

People have asked is whether we install “Solar Kits” that some home improvement businesses and online dealers sell at good prices.

The short answer is no, and there are several reasons.

First, most of the “kits” we’ve looked at are anything but complete. Racking, grounding, disconnects, wiring, and other components are often missing. Customers are very disappointed to learn this, often after the purchase has been made – ouch!

Second, we would never recommend the components that are in the kits, and therefore we can’t support them. If we install it, we own it as a support issue going forward.

Since we install a lot of grid-tied, battery backup systems, we also field a good many calls about certain online businesses selling grid-tied, battery backup systems that they describe as “plug-and-play”. Our electricians will be surprised to learn this, because we find that even the most experienced electricians we bring on board take a number of installs to become comfortable with the technology and installation techniques we use.

If someone describes a bimodal solar system to you as plug-and-play, it’s time to move on to a qualified vendor.

Caveat emptor, my friends.

 

Ground Mount versus Roof-Mounted Solar Systems

On a national basis, the vast majority of residential solar systems are roof mounted.  It makes sense.  It is space that is not being used, and the roof often has the best orientation to the sun’s path, and is the most shade-free area on the property.Untitled1

But in many cases, we encourage customers to at least consider a ground mount system.  The two main reasons are:

  1. You can precisely orient the array to the sun path – allowing for maximum annual production.
  2. If your array is part of an emergency power system (battery backup) and you get a big snow, it is easy to get the snow off of the modules, which is very important for an emergency power system.

For some customers, a ground mount is not a good option. For example, you may have a roof with a great orientation and pitch that is better than, or as good as, any ground mount system.

Keeping food safe when the power goes out

The year’s first snowstorm, Winter Storm Hercules, is living up to its name.

It’s dumping snow from Bangor, ME, to as far west as Chicago and as far south as the West Virginia-Kentucky state line – enough snow cancel 2,300 airline flights.

But that’s not the worst of it.

With freezing and below-freezing temperatures as far south as Central Virginia, power lines are starting to ice up. When power lines ice up, they sag, often break, and cause power outages. And when the power goes out, so do appliances like refrigerators and freezers, that keep your food from going bad.

So right now, these USDA tips for keeping food safe to eat are particularly worth following:

  • Fill Ziplock bags, empty soda bottles, and other plastic containers with water and freeze them. That way they can keep perishables in your freezer, refrigerator, and coolers (see below) cold.
  • Freeze food in your refrigerator that you don’t need immediately (meat, poultry, milk, and leftovers such as chili and soup, for example). If you loose power, this will buy you some more time by keeping them at a food-safe temperature longer.
  • Pack everything tightly together in the freezer and refrigerator to help keep everything cooler longer.
  • Have coolers on hand, ready to be filled with ice packs, frozen foods and refrigerated perishables.
  • If the power goes out, keep your refrigerator and freezer doors closed as much as possible. A fully packed, closed freezer will hold its temperature about 4 hours. A half-filled one will keep food safe for only half as long.
  • Look for visible ice crystals in your food. If they’re there, the food’s good to refreezing or cook and eat – even if it’s been in a sealed freezer without power for days.
  • If you’re not sure whether something’s safe to eat, use a cooking thermometer. If a food’s temperature is below 40˚F, it’s safe. If not, throw it out.
  • Also throw out any meat, poultry, fish, milk, eggs, soft cheeses, foods labeled “keep refrigerated,” and other perishables that have sat in your refrigerator for 4 hours without power. Hard and processed cheeses, butter and margarine, whole, uncut fruits and nuts, opened fruit juices and canned fruits, peanut butter, baked goods, and raw vegetables are safe.
  • Never taste an item to see if it’s still good; it most likely isn’t.

And after the power comes back on again, you might think about calling Milestone Solar about a solar power system with a battery backup bank. It’ll keep your fridge, freezer microwave working while the power’s out – for days on end, because it recharges whenever the sun is up. And when the snow stops and you have your electricity back, it’ll save you as much as 50% on your regular, monthly electric bills.

 

 

Red Cross advice for dealing with a blackout

If you already have a Milestone Solar system with battery backup, you can skip most of this, because it won’t apply to you.

Your sealed, high-tech battery backup bank will be storing up electric power with every ray of the sun (and recharging every day)  – enough power to keep your essential appliances going until the power comes back on, even if that’s days, even weeks, later.

For everyone else, the following pointers from the Red Cross can be important. That big pre-Thanksgiving storm was only the beginning of the snowstorm season. Once winter officially arrives, there’s be more snow, causing more icing up on power lines, more breaks and more outages.

Food Safety

  • If a power outage is 2 hours or less, don’t worry about losing your perishable foods.
  • Don’t open your refrigerator and freezer doors unless you have to. Use perishable food from the refrigerator first. An unopened refrigerator will keep foods cold for about 4 hours.
  • After perishables from the refrigerator are gone, then use food from the freezer. A full freezer will keep the temperature for about 48 hours (24 hours if it is half-full) if the door stays closed.
  • Use your non-perishable foods and staples after you’ve eaten all the food from the refrigerator and freezer.
  • If it looks like the power outage will continue beyond a day, get ice from an unaffected area and prepare a cooler for your freezer items.
  • Keep food in a dry, cool spot and keep it covered at all times.

Electrical Equipment

  • Turn off and, if you can, unplug every electrical appliance that was on when the power went out – particularly sensitiver electronics like computers. This will protect them from surges and spikes when the power returns.
  • Leave one light plugged in, so you’ll know when  the power’s back.
  • If you absolutely have to drive, drive extra carefully. Remember that traffic lights and street lights are electric, so they’ll also be out.

Fire and Carbon Monoxide Cautions

  • Unlike a backup battery bank, generators, grills, camp stoves and other devices that burn gasoline, propane, natural gas or charcoal can emit toxic exhaust fumes or cause fires. So don’t use them in your home, garage, basement, crawlspace or other enclosed areas. And if you use them outside, use them away from doors, windows and vents that could let the exhaust indoors.
  • Install carbon monoxide alarms in central locations on each floor and also outside bedrooms. That way, you’ll have warning when deadly carbon monoxide starts building up.
  • If a carbon monoxide alarm goes off, quickly move to where there’s fresh air – outdoors or by an open window or door.Once you’re there, stay there. Call for help  and remain there until emergency help arrives.

After the Blackout

  • Watch out for downed power lines. Don’t touch them, keep your kids and pets away from them, and report them.
  • Throw away any food that’s been exposed to temperatures higher than 40° F (4° C) for 2 hours or more, or that has an unusual odor, color or texture. When in doubt, throw it out!
  • Remember that food that looks all right and smells all right may not be all right. When they’ve been too warm too long, bacteria can start growing quickly. Many of these bacteria carry food-borne illnesses, and some produce toxins that even cooking can’t destroy.
  • If food in your freezer is colder than 40° F and has ice crystals on it, you can refreeze it.
  • If you’re not sure food is cold enough, take its temperature with a food thermometer.

 

 

 

Power outages have many causes, but one sure cure.

Readers of the  New Castle, PA, News got their papers late today because a power outage shut down the printing plant. While Penn Power eventually restored electricity, the cause of the outage is still unreported.

But it could have been almost anything.

On October 28, in Moundsville, WV, the cause was copper thieves, who cut through a power substation’s fence, broke the lock on the control house door, started helping themselves to 2 gauge copper wire, and tripped a circuit breaker in the process. About 3,000 homes and businesses were without electricity for almost two hours, and schools were closed.

The day before, just as schools were letting out in Farmington, VA, a failed lightning arrestor knocked out power in about 2,950 homes and businesses – and all the city’s traffic lights. It took four crews nearly an hour to restore it.

And Lynchburg’s downtown business district, as noted before, has been plagued with a whole string of outages caused by squirrels eating the insulation.

But while power outages can have many causes, there’s one best way to avoid them – and that’s with a Milestone Solar array with battery backup. Lynchburg, the home of those hungry squirrels, for example, enjoys 219 days with sunshine a year – and on each of those days, solar power can be charging a sealed, state-of-the-art battery bank.

When the power goes out, that battery bank kicks in – keeping your lights on, your food fresh and your appliances running – day and night, until the electricity comes on again, with no flammable fuels and no toxic emissions. And when it does, your Milestone Solar system cuts your electric bills by as much as 50%, earns you a tidy tax credit, and, according to Newsday, increases your home’s value by 3 to 4%.

 

 

 

Popular Mechanics warns about generator risks

Today, PopularMechanics.com posted, “How Not to Die: 20 Survival Tips You Must Know.”

Must-know survival tip #17 is of particular interest to anyone worried about power outages:

Use Generators Safely.

After Hurricane Sandy, many homeowners used portable generators to replace lost power, leaving the machines running overnight and allowing odorless carbon monoxide to waft inside. The gas induces dizziness, headaches, and nausea in people who are awake, but “when people go to sleep with a generator running, there’s no chance for them to realize that something’s wrong,” says Brett Brenner, president of the Electrical Safety Foundation International.

STAT: Carbon monoxide from consumer products, including portable generators, kills nearly 200 a year. Of the Sandy-related deaths, 12 were due to carbon monoxide poisoning.

 

A  Milestone Solar system with battery backup gives you power without the risk. Its high-tech, sealed battery backup bank kicks in as soon as the electricity goes out. It keeps supplying your home or business with electricity without deadly carbon monoxide – and with no exhaust emissions of any kind. You never have to refuel it. It keeps your power on for days, because it starts recharging whenever the sun rises. And when the power’s back it, it cuts your electric bills by as much as 50%. So call us toll-free, or email, to learn more.

 

 

 

8 ways to survive a power outage with kids

Blackouts aren’t fun to begin with, and for tech-loving kids they can be torture, East Texas television station KLTV advises. So they put together these ideas for “turning this surprise into a period of family bonding and fun.”

  1. Glow-stick games – Not only do glow sticks add light, but kids can bend them into bracelets and play glow-in-the-dark tag.
  2. Go camping at home – Now’s a good time to build that fort in the living room with couch cushions. Or you could pitch an actual tent. No campfires on the living-room floor, though.
  3. Ice-cream social – It’s going to melt anyhow, so why not enjoy it while it’s still relatively solid? Invite friends and neighbors to bring their melting ice cream too, and make a party of it.
  4. Shadow puppet show – You’ve got hands and fingers, and you’ve got plenty of darkness. All you need is a flashlight.
  5. Play Mad Libs – You can read from them and fill in the blanks by flashlight.
  6. Make greeting  cards – For birthdays, for holidays, for the local nursing home. You just need paper, crayons, kids’ imagination and creativity, and, if the power goes out after daylight hours, flashlights.
  7. Backyard barbecue and Olympics – Might as well fire up the outdoor gas grill and barbecue that meat that would otherwise spoil in your now-warm freezer. While the meat’s grilling, set up relay or three-legged races for the kids, with home-made medals for the winners.
  8. Wash the dog – You have to do it sometime, you can do it outdoors, and, says KLTV, it’s always good for a laugh (except for the dog).

Of course, the best way to survive a power outage is to avoid it in the first place, and that’s precisely what you can do with a Milestone Solar system with battery backup.

A sealed, high-tech battery bank stores up solar-generated electricity, kicks in the instant the power goes out, and recharges with a dependable power source that rises in the East every morning. When the electricity’s working again, the rest of your Milestone Solar system cuts your bills in  half, earns you thousands of dollars in tax credits and incentives, and increases your home’s value.So why not phone or email for a Free Solar Evaluation?