3 things to know about Malta, the Google-incubated and Bill Gates-backed startup
The energy storage technology company is proving that batteries aren't just for backup anymore. Read More

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The first full work week of 2019 is almost over! Before the year-end holidays, the energy press sizzled with headlines trumpeting the $26 million, Series A funding round for Malta Inc., an energy storage technology that nested in Google parent Alphabet’s famous Moonshot Factory X before hatching as a standalone company in December.
It wasn’t just the size of the infusion that got people talking — it was also the high-profile lead investor: Breakthrough Energy Ventures, the organization backed by a boatload of billionaires interested in guiding the next-generation of power technologies, including Bill Gates, Richard Branson and Jack Ma.
The money will go toward developing the first pilot installation for the thermal storage technology. The approach is relatively well-proven: Electricity can be stored as heat using molten salt or as cold in an antifreeze fluid.
Intrigued by the pedigree, I spoke with two executives from the Malta team — the CEO, former investment banker and hydropower exec Ramya Swaminathan, and the mechanical engineer who is the heat exchanger technical lead, Adrienne Little — to learn more about what the Cambridge, Massachusetts-based company hopes to achieve. Here are three takeaways from our discussion.
1. This is not intended to be a lithium-ion battery replacement. There are myriad reasons, but let’s start with the physical constraints. A 10-megawatt-capacity system will require a footprint of 164 feet by 164 feet, which sort of makes it a difficult proposition for urban or densely populated environments to cram in somewhere. It’s more likely to show up alongside a generation facility that is more rural or suburban, such as a wind farm or solar photovoltaic array.
Then there’s this factor: An installation of that size would be capable of providing eight to 20 hours of backup power. That’s at least double the time that the current stationary battery technologies are capable of supporting.
That makes the closest rival technologies to what Malta is working on either compressed air or pumped hydro, although without the specific geographic requirements of either (no underground caves or mountain lakes necessary!).
According to Malta’s press materials, the sorts of applications the company will explore will include peak load shifting, support for industrial or military installations and backup for microgrids. Not so surprisingly given its Google pedigree, the system potentially could serve as a source of distributed electricity load for data centers.
One last thing: The materials aren’t so “rare,” unlike lithium-ion, which requires precious minerals that may be tough to acquire in the future.
2. Don’t assume the pilot will be in the United States. Aside from Breakthrough Energy, the two other backers declared publicly for this round are wind, solar and energy storage developer Concord New Energy Group (formerly China WindPower) and Swedish heating, ventilation and air-conditioning (and many other sorts of industrial equipment) company Alfa Laval.
Given the multinational stock, the pilot could show up anywhere.
3. Don’t expect to see anything quickly. Although Malta’s technology has been put through a “rigorous evaluation and de-risking process,” Swaminathan told me it would take several years for a pilot to be in place. It will take that amount of time to design a commercially viable version of the system and to raise more capital for the buildout.
In any case, Malta had better get a move on.
Every time I blink, it seems, I read about another energy storage project. Hawaiian Electric Co. just proposed seven of them to state regulators, with a combined capacity of 1,048 megawatt-hours.
