by Jess Aloe
Late in April, Elon Musk, the billionaire founder of PayPal, SpaceX, Tesla and the chairman of SolarCity, announced a new battery designed to power homes, businesses and eventually, the grid itself.
“This is how it is today,” Musk said during the announcement, about how the world gets its power, pointing at a photo of smokestacks. “It sucks.”
“Save us, Elon!” yelled out a member of the audience.
“We have this handy fusion reactor in the sky called the sun,” Musk said. He spoke about the need to store the power of the sun. Part One, he said, to getting away from fossil fuels has been solved. Part Two–the problem of batteries–still needs work.
“The problem with the existing batteries,” he said, “is that they suck.”
“That’s the missing piece. That’s the thing that’s needed to have a proper transition to a sustainable energy world.
One of Tesla Energy’s partners in the business space–along with Amazon and Target–is EnerNOC, a Boston-based company that creates energy intelligence software.
The Boston area is a hotbed of clean-tech innovation, from EnerNOC to Greentown Labs in Somerville.
The clean-tech hub
In 2010, four start-up guys were looking for a place to build their prototypes near MIT. Unlike developing an app like Uber or a website like Facebook, creating new clean technologies like airborne wind turbines takes up some space.
First, Greentown Labs took up residence in the Seaport, part of Boston Mayor Tom Menino’s vision for an Innovation District. The four companies (Coincident, Altaeros, Promethean Power and Oscomps Systems) were joined by others. They started networking with other engineers and innovators in Massachusetts and got support from the quasi-state agency, the Massachusetts Clean Energy Center.
Eventually, they moved across the river, to the city of Somerville. Now, Greentown Labs is home to dozens of companies and employs over 100 people working on energy and “clean tech” innovation.
It’s the largest clean tech focused incubator space in the country, and people come from all over to set up shop there. In the vast lab space, some companies are making wind turbines to replace dirty diesel generators, or pods that can inspect rails for flaws that cause derailments (the cause of many natural gas accidents) or making HVAC more efficient.
Today, Greentown is part of a growing trend in the United States towards energy efficiency and clean technology. Solar and wind are booming. It’s cheaper than ever to install solar panels. Financial incentives and the plummeting prices have turned what used to be the sole realm of environmentalists into a viable way for Average Joe homeowners to cut costs. Wind farms are popping up all over the United States.
The biggest bottleneck holding renewable energy back today is storage. It’s a problem being faced by everyone from the startups at Greentown to Musk.
Moving away from fossil fuels
President Obama ordered a review of the country’s energy landscape and infrastructure that wrapped up in late April. “The U.S. energy landscape is changing,” it concluded. The United States is now the world’s leading producer of oil and natural gas, making it less dependent on foreign oil than it has been since 1971.
But it’s not just production of fossil fuels that’s driving the change, as noted in the government’s report. Between 2005 and 2014, U.S. consumption of gas fell as cars became more fuel efficient. During the same period,” U.S. electricity consumption was flat,” and “total energy use declined by 1.9 percent.”
And a recent study released by the Rocky Mountain Institute found that “rising retail prices for grid electricity and declining costs for solar PV and batteries mean that grid-connected solar-plus-battery systems will be economic within the next 10-15 years for many customers in many parts of the country.”
In other words, the electric bill is going up, and the solar bill is going down.
And while many have focused on the building of more panels and more turbines, the battery part of that is just as important.
Craig Garvin is a senior engineer at Altaeros Energy, one of the founding companies at Greentown. They’ve made an airborne wind turbine, which they call a “BAT.”
Altaeros has gotten to the point where its moving beyond prototyping and into manufacturing. The company markets its turbines as an alternative to expensive diesel generators, which can be deployed in remote locations far off the grid to bring clean, cheap energy to places like scattered Pacific Islands, or Alaska.
Their short-term path is “cautious and well thought out.”
It’s a “surprisingly large market,” and there’s a need for them.
The turbines are easy to integrate.
“As long as there’s existing generators, it’s really easy,” he said.
But what if you want no diesel generators?
That’s the challenge, and it’s industry-wide. “All renewable energy has intermittency problems,” Garvin said.
Coal and nuclear power plants, barring any kind of problem, consistently put out the same power output. As long as there’s enough pipeline, natural gas-powered plants can keep up with the peaks in demand.
But sometimes the wind stops blowing, and sometimes the sun goes down. Sometimes, wind and solar makes too much energy, and it doesn’t have anywhere to go.
To make renewable energy reliable enough to be a substantial part of the energy mix, wind and solar energy has to be stored so it can be released back during the darkest, stillest nights.
Lauren Hartle, a PhD candidate at Harvard, is working on a new kind of battery that has potential to store energy. “The issue,” she said, “is that we demand that power be accessible whenever we want it.”
So the power grid needs a lot of backup capacity, even if most of it goes unused most of the time. “The problem gets a lot trickier when you try to start integrating renewable resources,” she said. “If you can basically just store all the energy that you produce you can put out an average power and just take power when you need it, and there’s not nearly this need to have all these extra sources to have enough power to meet demand.”
“Storage plus renewables is actually a reasonable option going forward in the future.” she said. Without storage, though, people either need to accept a lack of reliability or accept less green fuel sources as part of the energy mix.
There are some storage options that exist. Pumped hydro, for one. You can use renewable power to run a dam in reverse–then run the dam forward when you need the power. But there are geographic limitations on dams.
The problem of batteries
Most batteries today are based on lithium-ion technology. The technology has its flaws–its expensive, it wears out quickly, and it uses toxic materials that can burst into flames. Musk’s much-heralded batteries are based on lithium-ion technology as well, but other Hub innovators are exploring other routes.
Hartle’s group, which is headed by Michael Aziz, professor at the Harvard School of Engineering and Applied Science, is working on a flow battery. Unlike batteries in laptops or phones, they’re not worried about portability or weight. Hartle said they’re more concerned about efficiency–about losing electricity–and cost. If the batteries cost more than natural gas, it becomes a less attractive option.
In a flow battery, external tanks hold energy stored in chemical form, which then flow through an active cell–a meeting place. When the chemicals meet and react, it creates electricity. The external tanks are key. It makes the batteries flexible. To increase the power, just put a bigger tank of chemicals.
“The novel thing,” Hartle said, “is what goes inside these tanks.”
Flow batteries exist, but they’re expensive. The trick, Hartle said, is finding chemicals that are safe, cheap and efficient.
If the chemicals are too expensive, then it pushes the cost of the entire system up. If that cost gets too high, it becomes not worth it.
It’s also got to last, which means that the containers need to be tough. Some of those chemicals can be “pretty nasty,” Hartle said.
And it can’t lose too much power. Hartle and her team want to find a chemical that will allow a battery to discharge almost 100 percent of the power put into it. (No battery is 100 percent efficient.)
Hartle’s group, which is funded by the Department of Energy, is partnering with Sustainable Innovations to develop demonstration projects around Harvard.
They’re not the only New England-based group working on the issue. In 2011, Bill Gates invested an undisclosed amount into the work of an MIT professor, Donald Sadoway.
Sadoway and his team at MIT invented a “liquid metal battery.” While giving a TED talk in 2012, Sadoway said that he wanted to get away from the prevalent idea that they could create a battery and then “hopefully we’ll chase down the cost curve by making lots and lots of product.”
“Instead,” he said on stage at TED, “let’s invent to the price point of the electricity market.”
“This battery needs to be made out of earth-abundant elements. I say, if you want to make something dirt cheap, make it out of dirt –preferably dirt that’s locally sourced.”
They named the company Ambri. The Ambri team declined to be interviewed for this story, but wrote in an e-mail that while a commercial product was several years away, “we expect to have our first commercial prototypes in 2015.”
Solar prices have been dropping rapidly over the past few years. According to analysts at the International Renewable Energy Agency, they’re approaching “plug parity.”
In Somerville, companies like Altaeros are moving from the prototyping phase to the manufacturing phase. Greentown is beginning a push to start creating a network to connect manufacturers and its companies. Some have even outgrown Greentown, and have moved to their own office space.
And although they’re starting small, according to Altaeros engineer Craig Garvin, he hopes to see his airborne wind turbines aloft above major American cities.
They want to work it “incrementally.”
Like Musk, the long-term goal is to reduce the reliance we have on fossil fuels like oil and gas, which are causing damage to the environment.
The mission, Garvin said, “is to change the energy mix.”