Utility Dive, May 2, 2017
Fire code issues have hampered energy storage development in NYC, but progress is being made

Construction has begun on a landmark microgrid project in New York City.

The project, at Marcus Garvey Village, a mixed-income apartment complex in the borough of Brooklyn, is not significant for its size, but for the fact that it includes a 300 kW, 1.2 MWh behind-the-meter lithium-ion battery.

“It is a step in the right direction,” said Lt. Paul Rogers, who is with the Fire Department of New York’s hazardous materials operations division.

Fire safety issues have slowed the progress of BTM li-ion battery deployments in New York City, despite the fact that the city’s mayor in September announced a 100 MWh by 2020 solar-plus-storage target. As of year end 2016, there were only 4.8 MWh of storage installed in the city.

While the Marcus Garvey project may be a step in the right direction, it is only a single step, and it is an indication of the work that remains to be done before New York safety officials, from both the FDNY and the city’s Department of Buildings, can sign off on a BTM residential li-ion project.

The safety codes

The Marcus Garvey project is a commercial meter attached to a residential complex owned by L+M Development Partners. “It is more of a C&I project,” said Shane Johnson, vice president of global operations at Demand Energy, a subsidiary of Enel Green Power North America and the developer of the microgrid project. And the battery for the project, which also includes a 400 kW solar system and 400 kW fuel cell, is outside the building in a stand-alone container.

The container, in fact, was in some ways key to the project’s approval. Safety approval for the project did not require any changes to the base product or to the battery components themselves. But FDNY did request changes to the containment system for the battery. Specifically the department asked that container have the capability to be flooded. Rogers says the department was trying to avoid the possibility that firefighters would have to open a battery container in the event of a fire.

Over the past several years, exploding laptops and blazing hoverboards have drawn attention to li-ion batteries’ potential for unwanted ignition. While large scale industrial energy storage applications have more built-in safety precautions than small scale consumer applications, they still represent a threat for which there is relatively little practical experience, especially when it comes to li-ion batteries’ potential for outgassing of toxic substances and thermal runaway. Both of those threats are compounded when a battery is installed in a place like New York City with its high population density.

Recent studies by DNV GL have found that the outgassing from li-ion batteries resembles the emissions from burning plastic, a threat FDNY already knows how to handle. Studies have also found that thermal runaway can be addressed by cell module design.

In the Brooklyn project, that threat was addressed by the containment system and by two levels of fire suppression, both of which take place within the battery container. The first level is a dry agent, Novec 1230, that would be deployed inside the battery container in case of a fire. The second is a hose connection that allows firefighters to flood the container with water.

The Marcus Garvey project is the “first logical step toward moving indoors,” said Doug Staker, vice president of market and business development at Demand Energy. “It answers some questions; it raises others.”

While Staker notes that some concerns about toxicity seem to have been allayed to some extent, there are still concerns about fire intensity. One way to address that concern is with self-contained cabinets, such as in the Marcus Garvey project. “My guess is that is where we are going to end up,” he said.

Staker says Demand Energy is in the process of identifying projects where li-ion batteries could be deployed. Those could include C&I installations where there are outdoor space that could accommodate a self-contained battery system, such as adjoining parking garages. He said Demand Energy is taking an incremental approach, rather than trying to “hit a home run every time.”

Meanwhile, the company continues to work with a variety of stakeholders, including the FDNY and New York’s Department of Buildings. “It is a very collaborative process,” Staker said. He says that process could result in a set of guidelines for the industry within a year.

It is also a complicated process with a variety of stakeholders from industry, city agencies, consulting groups and standard-setting organizations, such as the National Fire Prevention Association (NFPA).

One of the sticking points right now is with the NFPA’s committee on ventilation. “The main issue is prescribing that a BTM project update the building infrastructure in order to accommodate the battery, which is a nonstarter,” said  Davion Hill, energy storage leader, Americas, for DNV GL.

DNV is working on several fronts to provide data to develop New York’s fire code for stationary energy storage. The firm is working under contractor with the New York State Energy Research and Development Authority’s Energy Soft Costs program and with the City University of New York and with the New York Battery and Energy Storage Technology Coalition (NY-BEST).

The Soft Costs program is scheduled to wrap up in 2020, which, Hill notes, is just in time for California’s 1.3-GW energy storage mandate to be wrapping up.

“Meanwhile the market continues to seek answers,” said Hill. He says DNV will soon be publishing recommendations stemming from the firm’s most recent studies in order to give “guidance to the market.”

While he continues to engage in discussions with all the stakeholders, Rogers is quick to say that the FDNY is not writing the standards, but is working with industry to get everyone to the table, including pushing the NFPA to take a lead in developing test criteria. As he notes, “if those tests could satisfy us, they could probably be used all over the country.”