The CUNY Energy Institute, headquartered at the City College of New York (CCNY), is an interdisciplinary research center that brings the resources of the CUNY campuses together to aggregate and develop programs focusing on national energy needs. Faculty members from various fields collaborate with each other and with other US universities and Brookhaven National Laboratory. A particular focus is the effort to enable utilization of renewable energy sources by improving the efficiency of electric, electrochemical, and thermal energy storage.
The CUNY Energy Institute has amassed significant resources to sustain the research efforts needed to develop commercial products to advance sustainable energy technologies with low carbon footprints. The Energy Institute’s current research agenda in storage technologies includes developing a high cycle life, low environmental impact rechargeable battery for peak shaving, UPS, and off-grid applications. Their solution is zinc-nickel oxide flow batteries, which cost half as much as nickel-metal hydride batteries and have energy densities that are twice as high. In addition, research supported by ARPA-E, DOE, and NYSERDA has begun on a significantly lower cost (<$100/kWh) battery with a zinc-manganese dioxide chemistry. A third focus area is collaborating with Brookhaven, using the lab’s powerful accelerator facilities to track material changes within batteries in operando, to pinpoint the phenomena responsible for performance fade while batteries are cycling. Also, the NYC-based startup Urban Electric Power was spun out of the Institute to take innovations from the lab to market and is building a pilot-scale manufacturing facility in Harlem.
In the cellar of CCNY’s Steinman Hall – home base of the Energy Institute – a 30 kWh battery string assembled with zinc-nickel oxide flow batteries has been cycling for over a year. Operating at ~95% coulombic efficiency and nearing 900 deep cycles as the summer of 2013 ends, this string demonstrates the feasibility of storing large amounts of energy using the CUNY technology. With support from DOE, Con Ed, and NYSERDA, a larger 200 kWh string is currently being constructed using battery cells from spinoff Urban Electric Power. This string will reduce the peak electrical load in Steinman Hall and lower the university’s utility bill.
To scale up the Ni-Zn battery technology during the past few years, the Institute developed prototypes at several sizes: 6.5 Wh research batteries, 35 Wh small-scale “workhorse” batteries, and 1 kWh “monstero” batteries. This project involved overcoming many technical challenges that have traditionally limited Ni-Zn battery cycle life. Chief among these is zinc dendrite formation, which has been mitigated using the dual innovations of electrolyte flow and cleaning cycles that strip nascent dendrites. CUNY researchers used both experiment and mathematical modeling to study the fundamentals of dendrite formation and the effect of electrolyte flow on dendrites. This has led to a novel phase field model of electrodeposited dendrite growth and new understanding of the mechanism by which zinc atoms deposit during battery charging.
The CUNY project with Brookhaven is using the National Synchrotron Light Source to test the limits of alkaline battery materials: Zn-MnO2, the low-cost, safe materials found in the batteries consumers buy at the supermarket or drug store. While these so-called primary batteries are not ordinarily considered to be rechargeable, it turns out that they can be recharged if they are not used to their maximum capacity. Given that these batteries are very low cost and safe to use, the research team is exploring the possibility of using this established technology to meet the needs of grid-scale energy storage. With the help of ARPA-E funding, the Institute has developed grid scale prototypes of Zn-MnO2 batteries over the past three years, which may fit cost-sensitive applications better than the Ni-Zn chemistry.
According to Dr. Joshua Gallaway, a research scientist at the CUNY Energy Institute: "The guiding goal of the Institute is the energy independence of the United States. Our thrust in grid-scale batteries and energy storage originates here, but has an even deeper implication for the entire world. This is because getting our energy from greater proportions of renewable sources like solar power depends on cost effective ways to store energy on a global scale. With the help of NY-BEST, we believe our home -- New York State, New York City, and Harlem -- is indispensable in providing the intellectual resources for achieving these goals. The best place to start anything is with brilliant young people and a can-do attitude."
With groundbreaking work in multiple areas in energy technology that has already led to the formation of new industrial enterprises, the CUNY Energy Institute is indeed a tremendous resource to New York and the nation.