ReVision Energy employees Steve Dzubak (left) and Jared Cobb install a solar panel on the roof of a Concord home on Thursday, Aug. 27, 2015. In total, 25 panels will be installed and will supply the homeowner with more power than he is expected to use. (ELIZABETH FRANTZ / Monitor staff)

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If you are curious about what new technology is showing signs of disrupting an energy industry that is already being disrupted by solar panels, wind farms and electric vehicles, a discussion at the New Hampshire Energy Summit on Monday contained a pretty good clue in its title: “Storage Palooza.”

“It’s getting so that we can store really big chunks of electricity for significant periods of time,” said Charlotte Ancel, director of strategic development for Eversource Energy, one of the panelists at the session. She pointed to a “hockey stick” graph of electricity storage on the grid which showed amounts going up sharply as the cost of batteries, particularly lithium-ion, continue to fall.

“It’s still very expensive … yet people are adopting it like crazy,” said Chris Rauscher, director of storage market strategy for Sunrun, a firm that sells a package of solar panels and batteries to residences in most of New England, although not yet in New Hampshire.

The “Storage Palooza” session was the culmination of the three-hour Energy Summit, an annual session hosted by the Dupont Group consulting firm. The summit at the Concord Holiday Inn included talks and panel discussions about how to reduce pollution from transportation and buildings, mostly by shifting each one to use more electricity and less fossil fuels, and how to balance the three needs of an energy system: reliability, low cost and low pollution.

“Any two of those are possible, but doing all three at the same time is much more difficult,” said Katherine Bailey, a commissioner on the Public Utilities Commission.

Several speakers noted that climate change, which one called “the historic issue of our time,” is adding urgency to the need to create market structures, regulations and practices that will help reduce pollution, especially greenhouse gases, without sending costs too high.

Battery storage is increasingly becoming part of the technical side of the solution.

Electricity’s strength is it travels much more easily than other energy sources but its drawback has been that it is almost impossible to store. As a result, the power grid has been built to generate and transmit all the electricity we would ever need at the maximum moment, even if some or much of that generation and transmission often isn’t needed.

Improvements in batteries are making it feasible to build large amounts of short-term storage, lasting a few hours. Ancel pointed to several Eversource projects in Massachusetts and Connecticut at which large banks of batteries will be used to provide extra electricity during peak-use periods such as hot summer afternoons. These will replace fossil-fuel power plants that can quickly provide bursts of energy during peak periods, commonly known as “peaker plants.”

Because peaker plants are expensive and often relatively dirty to operate, replacing them is the area where battery storage can make the most money and have the biggest environmental impact.

Sunrun’s Rauscher pointed to the company’s program for a solar-and-battery program in Massachusetts totaling 20 megawatts, or almost twice the output of the Garvin Falls hydropower dam in Concord. It was apparently the first such program in the country to win a contract under the capacity auction, meaning that Sunrun has guaranteed that the program can produce a certain amount of electricity whenever needed. Such a guarantee is not possible with solar power alone, which only works when the sun is out, but combining solar with batteries makes it feasible.

Anne George, vice president for external affairs at ISO-New England, which oversees the six-state power grid, called Sunrun’s bid “an important milestone” that shows how storage and solar can be part of real-world energy production.

Another significant development mentioned Monday is Eversource’s $7 million battery storage program in the southwest New Hampshire town of Westmoreland. As being developed, it will provide backup power during outages, replacing the need for a new transmission line. The program will also include efficiency incentives and demand response, under which customers agree to reduce electricity usage during peak periods.

Battery storage still has great limitations, notably the fact that it cannot realistically provide large amount of power for more than half a day. Truly long-term storage of energy, for periods of weeks or even months to shift energy production from summer to winter, will probably never be feasible with batteries. Many advocates say this limitation means peaker plants will continue to be necessary for years to come.