Sign In or Create an Account.

By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy

Climate Tech

Lunar Energy Raises $232 Million to Scale Virtual Power Plants

The startup — founded by the former head of Tesla Energy — is trying to solve a fundamental coordination problem on the grid.

•
A Lunar Energy module.
Heatmap Illustration/Lunar Energy

The concept of virtual power plants has been kicking around for decades. Coordinating a network of distributed energy resources — think solar panels, batteries, and smart appliances — to operate like a single power plant upends our notion of what grid-scale electricity generation can look like, not to mention the role individual consumers can play. But the idea only began taking slow, stuttering steps from theory to practice once homeowners started pairing rooftop solar with home batteries in the past decade.

Now, enthusiasm is accelerating as extreme weather, electricity load growth, and increased renewables penetration are straining the grid and interconnection queue. And the money is starting to pour in. Today, home battery manufacturer and VPP software company Lunar Energy announced $232 million in new funding — a $102 million Series D round, plus a previously unannounced $130 million Series C — to help deploy its integrated hardware and software systems across the U.S.

The company’s CEO, Kunal Girotra, founded Lunar Energy in the summer of 2020 after leaving his job as head of Tesla Energy, which makes the Tesla Powerwall battery for homeowners and the Megapack for grid-scale storage. As he put it, back then, “everybody was focused on either building the next best electric car or solving problems for the grid at a centralized level.” But he was more interested in what was happening with households as home battery costs were declining. “The vision was, how can we get every home a battery system and with smart software, optimize that for dual benefit for the consumer as well as the grid?”

VPPs work by linking together lots of small energy resources. Most commonly, this includes solar, home batteries, and appliances that can be programmed to adjust their energy usage based on grid conditions. These disparate resources work in concert conducted by software that coordinates when they should charge, discharge, or ramp down their electricity use based on grid needs and electricity prices. So if a network of home batteries all dispatched energy to the grid at once, that would have the same effect as firing up a fossil fuel power plant — just much cleaner.

Lunar’s artificial intelligence-enabled home energy system analyzes customers’ energy use patterns alongside grid and weather conditions. That allows Lunar’s battery to automatically charge and discharge at the most cost-effective times while retaining an adequate supply of backup power. The batteries, which started shipping in California last year, also come integrated with the company’s Gridshare software. Used by energy companies and utilities, Gridshare already manages all of Sunrun’s VPPs, including nearly 130,000 home batteries — most from non-Lunar manufacturers — that can dispatch energy when the grid needs it most.

This accords with Lunar’s broader philosophy, Girotra explained — that its batteries should be interoperable with all grid software, and its Gridshare platform interoperable with all batteries, whether they’re made by Lunar or not. “That’s another differentiator from Tesla or Enphase, who are creating these walled gardens,” he told me. “We believe an Android-like software strategy is necessary for the grid to really prosper.” That should make it easier for utilities to support VPPs in an environment where there are more and more differentiated home batteries and software systems out there.

And yet the real-world impact of VPPs remains limited today. That’s partially due to the main problem Lunar is trying to solve — the technical complexity of coordinating thousands of household-level systems. But there are also regulatory barriers and entrenched utility business models to contend with, since the grid simply wasn’t set up for households to be energy providers as well as consumers.

Girotra is well-versed in the difficulties of this space. When he first started at Tesla a decade ago, he helped kick off what’s widely considered to be the country’s first VPP with Green Mountain Power in Vermont. The forward-looking utility was keen to provide customers with utility-owned Tesla Powerwalls, networking them together to lower peak system demand. But larger VPPs that utilize customer-owned assets and seek to sell energy from residential batteries into wholesale electricity markets — as Lunar wants to do — are a different beast entirely.

Girotra thinks their time has come. “This year and the next five years are going to be big for VPPs,” he told me. The tide started to turn in California last summer, he said, after a successful test of the state’s VPP capacity had over 100,000 residential batteries dispatching more than 500 megawatts of power to the grid for two hours — enough to power about half of San Francisco. This led to a significant reduction in electricity demand during the state’s evening peak, with the VPP behaving just like a traditional power plant.

Armed with this demonstration of potential and its recent influx of cash, Lunar aims to scale its battery fleet, growing from about 2,000 deployed systems today to about 10,000 by year’s end, and “at least doubling” every year after that. Ultimately, the company aims to leverage the popularity of its Gridshare platform to become a market maker, helping to shape the structure of VPP programs — as it’s already doing with the Community Choice Aggregators that it’s partnered with so far in California.

In the meantime, Girotra said Lunar is also involved in lobbying efforts to push state governments and utilities to make it easier for VPPs to participate in the market. “VPPs were always like nuclear fusion, always for the future,” he told me. But especially after last year’s demonstration, he thinks the entire grid ecosystem, from system operators to regulators, are starting to realize that the technology is here today. ”This is not small potatoes anymore.”

Blue

You’re out of free articles.

Subscribe to access Heatmap's exclusive climate and energy polling, award-winning journalism, and subscriber-only events. Save $57 on an annual subscription, just $156 $99/year.
To continue reading
Create a free account or sign in to unlock more free articles.
or
Please enter an email address
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
Daily Briefing

Think Congress Is Slow? Meet the Power Sector.

BAAJA would likely help speed up the U.S. transmission buildout, but there’s a chance we’re undercounting the benefits.

Power lines.
Heatmap Illustration/Getty Images

This is Heatmap Daily, a weekday digest written by our executive editor. Subscribe here.

As you may have seen, my colleague Emily Pontecorvo and I got the first look at the Rhodium Group’s analysis of what the bipartisan permitting bill will do to emissions.

Keep reading...Show less
Blue
AM Briefing

Neutral, at Worst

On Chinese hydrogen, Fermi upheaval, and British offshore wind

Smokestacks.
Heatmap Illustration/Getty Images

Current conditions: The Pineapple Express, an atmospheric river originating in the Pacific near Hawaii, is arriving in the Southwest laden with heavy rain that’s set to flood the region • Indonesia has the worst air quality in the world as forest fires rage along Sumatra’s southern coast • A cross-country storm will soak much of the United States on Tuesday’s Election Day.


THE TOP FIVE

1. Permitting bill’s worst-case climate scenario is still carbon neutral

The Senate’s grand compromise to simplify federal permitting on energy projects would likely drop emissions slightly as the benefits to accelerating deployments of clean energy infrastructure outweigh the boost the legislation could give to fossil fuels. Even under the worst-case scenario, emissions remain on the same trajectory as today. That’s according to a hotly anticipated new analysis by the Rhodium Group, the consultancy whose U.S. emissions estimates are among the most widely cited in American politics. The report, shared first with my colleague Emily Pontecorvo, found that provisions in the Bipartisan American Affordability and Jobs Act largely counteract each other on climate. The bill makes building transmission lines much easier, a key step to patching more renewables onto the grid. But it also makes new gas pipelines simpler to permit, clearing the way for a buildout of the infrastructure for the fossil fuel already dominating U.S. electricity and heating systems. Still, under the best-case scenario, the legislation could cut U.S. economy-wide emissions by 5% below where they would otherwise go in 2040. The bill could also slash energy bills by $78 per year and support construction of more than 200 gigawatts of clean energy capacity, as compared to a world where it didn’t pass. The Rhodium report is at least the second analysis yet to find that the bill could modestly lower emissions. The first, as I reported last week, came from the think tank Resources for the Future, which saw a slight drop in power-sector emissions relative to a world without BAAJA.

Keep reading...Show less
Blue
Energy

Exclusive: New Modeling Finds Permitting Bill Would Likely Cut Emissions

Even in the worst-case scenario, BAAJA wouldn’t increase emissions, an analysis by the Rhodium Group concludes.

Pollution and the Capitol.
Heatmap Illustration/Getty Images

The bipartisan permitting reform bill is likely to slightly cut greenhouse gas emissions and lower electricity bills by 2040 — or at worst leave emissions on the same trajectory that they are on today — as compared to the status quo, according to a new analysis of many of its provisions by the Rhodium Group, an independent research firm.

The analysis examines the policies in the Bipartisan American Affordability and Jobs Act, or BAAJA, that would have the most-clear cut effects on climate pollution and the energy system. It is the most comprehensive account of the bill’s effects on emissions so far, although it does not examine all of its provisions.

Keep reading...Show less
Blue