SolarEdge’s white-labeled ConnectDER meter collar on a combination meter/main electrical panel.
Reducing the stubborn soft costs of solar + storage is a much-discussed topic that will only become more important as the residential tax credit ends. While the prices of major solar equipment like panels and inverters continue to come down, the specialized electrical work required in many solar installations keeps costs high.
“All that fat, soft cost in the middle is still basically the same. You have more sophisticated ways of doing permitting, more sophisticated ways of doing the evaluation of the roof and things like that. But at the end of the day, it’s still an industrial project,” said Whit Fulton, founder and chief product officer for ConnectDER.
Homes typically need a 200-A electrical panel to support the extra power from a solar, storage and/or EV charger installation. Until recently, solar projects required installing a dedicated circuit breaker on the electrical panel — a costly upgrade that could only be done by a licensed electrician. If the home’s electrical service was lower than 200 A, they would likely need an entire main panel upgrade or new subpanel installation to go solar.
Increasingly smart products called meter collars have the potential to simplify solar + storage interconnection and take a big chunk out of those expenses. These tools, manufactured by companies like ConnectDER, Enphase and Tesla, started as utility products that allowed customers to add temporary backup support like generators.
ConnectDER’s founder saw the potential for meter collars in the renewable energy space while working for a company selling DIY-style packages of batteries and inverters. The product was meant to be accessible and low-cost, but the wiring and electrical work required to interconnect it made the job much more expensive than intended. After watching a utility meter change-out, Fulton started thinking of the potential for avoiding those exorbitant electrician-based charges by plugging solar + storage installations directly into the meter.
“I realized, ‘Oh, let’s see — it’s a house-sized socket, and if we create an intercept there, we can just plug solar in, or batteries, or even [EV] chargers or whatever comes along … in a much more cost-effective way that is universal, instead of all the bespoke customization,’” he said.
Fulton received a Dept. of Energy SunShot Initiative grant to work on the concept in 2012, and ConnectDER was born.
Meter collar evolution
Around 2017, California established a new rule requiring the use of smart solar inverters that communicate autonomously with the grid. Before long, most inverters on the market had these kinds of “smart” capabilities. As inverters evolved, meter collars did too.
“Inverters need more than just a power place to interject. They need to have a reading of the power flow through the meter. They need to be able to have that for both PCS (power control system) control, to reduce their output in order to be installed on smaller services without doing a service panel upgrade, and they also need it for third-party ownership,” Fulton said.
A diagram of Tesla’s Backup Switch.
Along with providing information on power flow for third-party ownership contracts and PCS requirements, meter collars can make it easier to add EV chargers to homes without electrical upgrades, as seen with ConnectDER’s EV meter socket adapter. Perhaps most importantly, as storage attachment rates continue to grow, meter collars like ConnectDER’s IslandDER can act as a simple microgrid interconnect device (MID) that disconnects the project from the grid and switches to battery backup when the grid is down or when it’s programmed to take advantage of time-of-use rates.
“If you look at any vendor in the market, they’ve all had some type of gateway-style device, and inside the gateway is a device called an MID. What ConnectDER has done is they’ve taken that same MID, and they simply moved it from one location to another, so it’s easier to install,” said Alex Dinh, director of residential product management at SolarEdge.
In many Western states including California, meter collars are all but required for a solar + storage project to disconnect from the grid. Meter/main combination electrical boxes with the meter directly connected to the front of the main service panel are the norm in that state and some others. There is no simple way to install a disconnect switch in front of the electrical panel on combo boxes, unlike split boxes that have separate electrical panels and meters.
“Instead of ripping out the entire service panel and rewiring the whole thing, which costs many thousands of dollars, you could just put this in between, and it gives the system the ability to do backup,” Fulton said.
Meter collar market
Many residential battery manufacturers, including SolarEdge, FranklinWH, Lunar Energy and EcoFlow, are compatible with ConnectDER’s meter collars. SolarEdge chose to white-label the ConnectDER solution because of its solid track record and flexibility with different brands, in case customers want to pair a SolarEdge inverter with a different battery or vice versa.
“We knew we wanted a meter collar product that would help ease the installation experience with our customers, it was gaining good utility adoption, and we knew that we needed a solution that would help to isolate the home from the grid to allow a good and efficient backup system,” SolarEdge’s Dinh said. “There was already a good solution on the market from ConnectDER, so we didn’t want to reinvent the wheel.”
Although many companies chose to partner with ConnectDER for meter collars, a few major power electronics manufacturers offer their own solutions. Tesla sells its Backup Switch to reduce the components needed for Powerwall installations. The company says it cuts Powerwall installation times by more than six hours.
Enphase’s IQ Meter Collar.
Enphase recently rolled out the IQ Meter Collar in its 4th-generation Enphase Energy System, part of a package that includes a battery and combiner box. Meter collars were an obvious addition for the company that is championing decentralized, intelligent whole-home energy systems.
“What you are looking at now is something that we’ve been pushing — decentralization, where the home is a unit of intelligence. The point of common coupling, which is the meter, is where we are now adding a lot of intelligence,” said Raghu Belur, co-founder and chief products officer at Enphase.
Belur said Enphase’s IQ Meter Collar can autonomously decide when to disconnect from a faulty grid and reconnect when it’s back up and running. It also collects information on both ends of communication — assessing grid performance as well as Enphase system performance, and relaying that back into the cloud.
Belur thinks meter collar technology can lower barriers to residential renewable energy moving forward. For example, EV owners could purchase just a bidirectional charger and a meter collar to have whole-home backup.
“For our installer partners, that really dramatically opens up the available market that they can go serve,” he said.
Utility approval roadblocks
Meter collars can be a breakthrough for lowering solar + storage install costs, but they’re still not widely available. Since installing meter collars requires interaction with utility-owned infrastructure, utilities must individually approve their use. Meter collar manufacturers are actively working with regulators to expand approvals nationwide.
In some jurisdictions, utility workers are the only ones who can install these devices, which comes with an additional fee. ConnectDER is working to change that too and get to a point where credentialed installers can put the meter collars in themselves.
Fulton believes every state will be open for meter collar business eventually.
“We’re not asking for incentives. We’re not asking for ratepayer money, we’re not asking for taxes. We are asking simply to allow a customer to use their own infrastructure in their home to connect things more easily,” he said. “That argument has worked really well in regulatory legislative work that we’ve been doing in various states, and it is beginning to trundle forward a bunch of states where we didn’t have to do regulatory legislative work, where they’re just like, ‘OK, this makes sense.’”
