Energy Storage: Falling Costs, Major Gains

As published in EI New Energy - Vol.6, No:7, Feb. 16, 2017

As the energy transition charges forward, one technology holds the keys to both the rise of renewable power and the evolution of auto transport: Batteries and other energy storage technologies, assuming they continue to improve, will allow intermittent solar and wind to keep gaining market share while accelerating the shift away from oil-based transport. But can energy storage make economic sense, or will it only add to costs? Matt Roberts, executive director of the Energy Storage Association in Washington, tells EI New Energy that US energy storage costs have fallen “very substantially” in recent years and are “well where they need to be.” As a result of the economic gains and technological advances, energy storage is gaining serious attention from a far-reaching cast of characters including automaker Tesla, the Pentagon, French oil major Total, and President Donald Trump’s administration.
Big, independent power producers have seen storage costs fall over the last year by a massive 70%. “That’s due to a lot of factors. One, it’s a widget, so when you make more of it, it gets a little bit cheaper,” Roberts says. Another is declining system costs, including for electronic devices such as inverters. In customer-driven energy storage, in which the units are based at the user’s home or business, storage costs are also tumbling, with one California developer citing a decline of 70% from mid-2015 to end-2016. “The similarity here is the market pull has finally kicked in — making these technologies valuable, therefore driving deployment, driving standardization, and making them a lot more affordable,” Roberts says. “Now that you can profit, there’s a motivation to really pursue and push this.” Going forward, the challenge for the energy storage business is not cost, it’s value, Roberts says.
In transport, electric car battery costs have also “come down significantly” and “you are going to see cheaper and cheaper electric cars,” Roberts says (p2). “The bigger wind is trucks. The trucking and shipping industries are some of the next big places for electrification that will continue to have bigger market shares, will continue to drive costs down.” California automaker Tesla has made waves in the energy storage business and is a key early mover in creating a bridge between the power and auto sectors. Its Gigafactory in Nevada now alone produces as many batteries as “everywhere else in the world,” Roberts says. Tesla’s PowerWall technology — a home battery typically paired with rooftop solar generation — will be key to driving consumer awareness of storage technology, he adds (NE May 7’15).
Many established energy companies are jumping into the storage space as well. Investments, such as Total’s acquisition of French battery maker Saft, are “minor compared to their business, but they are major compared to our business,” Roberts says (NE May12’16). Another example is French natural gas and electricity company Engie, which has installed 4,000 electric car-charging points in Europe (NE May5’16). Utilities, including Exelon and Duke Energy, are also playing a big role in the storage business. “There’s a good mix of investments,” he says. “This is one of the few advanced energy industries where there’s a lot of buy-in from every stakeholder. Everyone comes out ahead.”
The Pentagon sees a number of strategic advantages in storage technology. In the field, storage is being paired with solar at military installations so that diesel isn’t transported through dangerous territory.  “You’re making soldiers safer,” Roberts says. For large bases in the US, the military is using storage to develop self-sufficient grids known as “microgrids” (NE Sep.19’13). “Our military bases want to be grid-independent so if something central happens, they can still operate and generate power from renewables,” Roberts says. In addition, the “emergency and national security” section of President Donald Trump’s infrastructure plan includes a goal for energy storage and grid modernization in an effort to prevent blackouts. “He’s coming at it from a homeland security angle,” Roberts says. Hospitals, hotels, college campuses, large commercial buildings are also seeking storage as a back-up, Roberts says. “In a lot of these places, what they currently use is a diesel  generator. No one ever tests these diesel sets, and diesel and gasoline go bad.”  
Besides technological gains, the energy storage market has also taken off in the US due to “aggressive” procurement goals from the state of California — which is requiring 1.8 gigawatts of energy storage by 2020 — as well as favorable decisions from federal regulators and regional transmission organization PJM, Roberts says. Going forward, the energy storage business is seeking better market frameworks for energy storage to be bought and sold, from grid operators, states, and the federal government too.