Hybrid Energy Storage Systems Get the Best of Both Worlds

Hybrid Energy Storage Systems Get the Best of Both Worlds

But calculating the true costs and benefits of energy storage is still difficult math.

Many years ago, I was part of a U.S. Air Force program with the goal of reducing the battery weight carried by airmen and soldiers by 25 percent. The Air Force Program Office, after scouring the market for the ideal battery solution, quickly learned that no rechargeable battery could meet the power density, energy density, lifetime, and size/weight requirements.

However, they did not abandon the project — they took a hybrid approach to the problem.

Batteries are typically designed for high-power applications (i.e., “sprinter” mode that provides lots of power in short bursts) or energy-dense applications (i.e., “marathon” mode that provides consistent lower power over long durations), and there are lifetime, performance, and cost penalties for using them in unintended ways.

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We Need a Better Way to Compare the Performance of Energy Storage Technologies

Grid-scale energy storage is getting a lot of attention this year. Pricing has come down and perceived value has come up — expanding the commercial viability of different technologies.

But the story is much more complicated. There are plenty of important technical and market-based nuances that need to be considered.

Technically speaking, battery chemistries drive performance, and they vary greatly. New nomenclature and standards are needed for comparing batteries across applications. As anyone who has cycled batteries in the lab will attest, the lifetime of the battery is dependent on how the battery is used and under what conditions. Continue reading the article at Green Tech Media…

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We Need a Better Way to Compare the Performance of Energy Storage Technologies

We Need a Better Way to Compare the Performance of Energy Storage Technologies

What’s the best metric for evaluating storage? No one has come up with one yet.

Grid-scale energy storage is getting a lot of attention this year. Pricing has come down and perceived value has come up — expanding the commercial viability of different technologies.

But the story is much more complicated. There are plenty of important technical and market-based nuances that need to be considered.

Technically speaking, battery chemistries drive performance, and they vary greatly. New nomenclature and standards are needed for comparing batteries across applications. As anyone who has cycled batteries in the lab will attest, the lifetime of the battery is dependent on how the battery is used and under what conditions.

Performance turns out to be difficult to communicate using a spec sheet, and vendors self-select the data they share. Consequently, the energy storage business has a bad reputation for over-promising.

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