Behind the meter (BTM) resources are increasingly being brought online and several utilities want to capitalize on the trend.
The key, according to Tesla Energy's former lead on products, is giving customers a simple process to add any distributed energy resources (DER) they want and to give utilities visibility and control of that process.
Arch Rao created Span after leaving Tesla in 2018, and launched a flagship product on Thursday that would incorporate those attributes into a single device — replacing one that exists in every home: the electric panel.
Span's smart electric panel, designed by a team of former Tesla engineers behind the Powerwall residential battery, would integrate advanced metering infrastructure (AMI) into the panel and allow customers to plug in any number of DERs, from solar panels to battery storage and electric vehicle fast chargers.
"I think Span is another example of energy technology innovation that happens when you allow competition," Audrey Lee, Sunrun's vice president of energy services, told Utility Dive.
"Space in the electric panel in the age of electrification is going to become much, much more of a premium."
John Castonguay
Chief innovation officer, Green Mountain Power
The company is first deploying its smart panel by partnering with select DER installers and residential battery providers in Hawaii and California, but the product aims to become integral to utility efforts to gain real-time host control of grid-edge assets, Rao told Utility Dive.
Thinking smart about inverters
As DER installations increase, more utilities will have to think about managing several interconnections, such as solar panels, battery storage, electric vehicle chargers, electric heat pumps and water heaters, according to Josh Castonguay, Green Mountain Power's chief innovation officer.
"Space in the electric panel in the age of electrification is going to become much, much more of a premium," he told Utility Dive. "Being able to discretely meter those [resources], even control those — that's really helpful."
Working toward a similar vision of grid modernization, states with high distributed generation penetration, like Hawaii and California, have started mandating smart inverters, which are "smart enough to... be listening to voltage and frequency" and provide grid supportive functions by "being a good grid citizen," Ric O'Connell, executive director at GridLab, told Utility Dive.
Span's product would allow customers to choose whatever providers they wanted, if they choose to participate in the grid or add their own generation and backup power. Most DER systems currently require their own proprietary inverters.
"One of the things that the Powerwall has as a limitation, if you will, is it is a Tesla-specific device," Rao said. "We're essentially building a common interface for batteries like Powerwall," instead of using a Tesla fleet controls system, which would in turn tie into the utility's grid interface.
The Span smart panel has the potential to "simplify everything we do as installers both today and for retrofits down the line," Josh Powell, CEO of a top Hawaii solar and storage installer, Revolusun Smart Home, said in a statement.
On the utility side, Green Mountain Power and others are already looking for grid modernization options as traditional meters age and as more DERs are brought online, Castonguay said.
In that context, Span's panel is one of several technologies seeking to offer a sophisticated fix for DER integration.
"The biggest challenge with DERs is that we haven’t quite figured out how to tie them to each other or into the grid" in an affordable, reliable way, according to Ryan Kennedy, CEO of Atom Power.
"[As with the Internet,] the way our world works is much more than distributed, decentralized, digitalized, right? And so I think that's the way the distribution system is going to work," O'Connell said.
Learning from Green Mountain Power's models of partnership
Castonguay and Rao worked together as part of an ongoing partnership between Green Mountain Power and Tesla. The utility deployed BTM batteries that it could control and use to shave peak demand, turning DERs into a grid asset.
Green Mountain Power is communicating directly and pulling data from battery storage devices, he said. In such instances, "we're not leveraging AMI... but we still need the AMI meter there to measure the rest of the home."
Span's smart panel would add metering capabilities to the entire home and all other devices that customers choose to integrate.
The utility can use a smart charger or a battery system to meter, "but if you want to do heat pump controls or a water heater control, or manage other devices in the home, "there [aren't] really good products out there for easy metering," Castonguay said.
"I think [Span's panel] can definitely shake some things up when it comes to traditional metering systems and AMI metering systems," he said.
When it comes to the granularity of metering, utilities and regulators will need to consider the amount of visibility needed for reliable service.
"The main question is ultimately what level of direct mapping and direct control of DER is necessary," Aram Shumavon, CEO of data aggregation group Kevala, told Utility Dive.
Larger industry trends
One way to increase visibility BTM while using automation has been for utilities to expand their AMI deployment, calling on regulatory commissions to approve programs that would give them more real-time data for residential load management. They're looking for a variety of partnerships and products to drive energy savings while adding more data.
On Monday, Xcel announced a partnership with Itron to build and install a "next generation" of smart meters across its system, to help "the industry shift to cleaner sources of power on an even more reliable advanced energy grid," according to the company.
"We should just be really cautious of seeking data and control behind the meter from customers."
Audrey Lee
VP of energy services, Sunrun
Other companies are testing and developing holistic power management systems, such as Atom Power, which recently launched a digital solid-state circuit breaker.
"For utilities, a digital circuit breaker unlocks the ability to seamlessly and instantly manage DERs for the first time," Kennedy says.
Atom's power management platform seeks to unify aspects like circuit protection, transfer switching, relaying and metering, transfer switching. However, one of the company's primary deployments will be with data centers instead of residents adding DERs.
However, customer choice and privacy remain a concern for utility regulators, according to Sunrun's Lee, a former advisor to the California Public Utilities Commission.
"The utility meter has traditionally been the line of demarcation between the customer and the utility," she said. "We should just be really cautious of seeking data and control behind the meter from customers. I think it's really important that customers should be able to choose how their devices are controlled and used."
