Skip to Content

Ultracapacitor Startup Gets a Big Boost

An energy storage startup gets new government funding.
October 30, 2009

An MIT spinoff just getting off the ground received a huge helping hand from the U.S. Department of Energy on Monday. FastCAP Systems, of Cambridge, MA, received a two-and-a-half-year, $5.35 million grant in the first round of funding ever issued by the new Advanced Research Projects Agency-Energy (ARPA-E). The company aims to commercialize a nanotube-enhanced ultracapacitor, an energy storage device that could greatly reduce the cost of hybrid and electric vehicles and of fast-responding grid-scale energy storage, making it easier to integrate renewable energy sources such as solar and wind-based power.

“The ARPA-E grant represents the ability to ramp up faster,” says Joel Schindall, the MIT professor in whose lab the technology was originally developed. “We now have the resources to do the things that we’ve been wanting to do for the last few years.”

ARPA-E was inspired by the Defense Advanced Research Projects Agency (DARPA); like DARPA, it is chartered with supporting high-risk, high-reward research–but ARPA-E is focused on projects that could provide innovative solutions to the problems of climate change and energy security rather than defense. An agency of the U.S. Department of Energy, ARPA-E received $400 million in initial funding from the federal government in April. On Monday, it announced the awardees in its first round of grants to small businesses, universities, and large corporations. Thirty-seven projects were funded, receiving an average of approximately $4 million each. ARPA-E received more than 3,600 concept papers, and the final winners were selected from about 300 full applications.

Nick d’Arbeloff, president of the New England Clean Energy Council, says that the ARPA-E award will make a big difference to the small companies that receive them. “An award of this type is huge,” he says. “It is a huge badge of honor and validation for other investors, that this is seen by the Department of Energy as a highly innovative, breakthrough technology, and one that every venture capital firm should be tracking.”

Ultracapacitors that use activated carbon electrodes are already on the market but are used only for limited applications, such as absorbing the energy produced by braking in hybrid buses and providing the quick bursts of power needed to get the large vehicles moving. The reason that they are restricted to such niche markets is that they cannot store enough energy to provide power over a long period of time.

Riccardo Signorelli, first a graduate student and later a postdoc in Schindall’s lab, developed a way to replace the activated carbon with vertically oriented nanotubes. This significantly increases the surface area and voltage of an ultracapacitor electrode, which in turn boosts the amount of energy that an ultracapacitor can store. Schindall’s group hopes to develop ultracapacitors that can store five times more energy than those on the market now, bringing their capacity up to one-quarter of the amount stored by lithium-ion batteries. Because ultracapacitors can be charged and discharged thousands of times more than a rechargeable battery, however, Schindall and Signorelli believe that reaching that goal would make ultracapacitors a viable and cost-effective solution for hybrid vehicles. In fact, hybrid buses and heavy-duty vehicles are the first market FastCAP plans to target.

Signorelli cofounded FastCAP to commercialize the nanotube-enhanced ultracapacitors, and he is the company’s president. While working at MIT, he has demonstrated electrodes that deliver the power density that the company pitched in its ARPA-E grant application. The ARPA-E grant, he says, will enable FastCAP to complete the process of putting the electrode into a packaged device that operates as predicted. Additionally, by the end of the grant term he plans to have determined the process that will be used for manufacture, built a pilot-scale production plant, and tested the devices in vehicles. Signorelli calls the ARPA-E grant “instrumental” to achieving these plans.

In the longer term, Signorelli also sees a role for FastCAP’s ultracapacitors providing short-term buffering to protect the electrical grid against sudden spikes in energy supply or demand. Currently, utility companies are required to maintain what are known as “spinning reserves,” which are turbines that are already running, so that when there are sudden surges in demand–say, on a hot summer day–the turbines can provide the extra electricity almost instantaneously. Ultracapacitors distributed throughout the network could provide a few minutes of reserve capability locally, without requiring utilities to burn fuel in a turbine to keep it spinning. That would not only decrease fuel requirements and carbon-dioxide emissions, Schindall says, but also allow companies to use the grid closer to capacity. If we could use the grid just 5 percent closer to capacity, he says, it would save billions of dollars in infrastructure investment.

Ultracapacitors could also ease the integration of renewable energy sources such as solar and wind power, which by their nature are intermittent. Without a way of instantaneously buffering energy from these sources, they could cause region-wide blackouts and will never be reliable enough to rely on exclusively.

Keep Reading

Most Popular

computation concept
computation concept

How AI is reinventing what computers are

Three key ways artificial intelligence is changing what it means to compute.

still from Embodied Intelligence video
still from Embodied Intelligence video

These weird virtual creatures evolve their bodies to solve problems

They show how intelligence and body plans are closely linked—and could unlock AI for robots.

We reviewed three at-home covid tests. The results were mixed.

Over-the-counter coronavirus tests are finally available in the US. Some are more accurate and easier to use than others.

conceptual illustration showing various women's faces being scanned
conceptual illustration showing various women's faces being scanned

A horrifying new AI app swaps women into porn videos with a click

Deepfake researchers have long feared the day this would arrive.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at with a list of newsletters you’d like to receive.