Recent battery management system advances are increasingly proving that the key to cost-effective energy storage might not be what you use… but how you use it.
Last year, for example, Energy Storage Report unveiled news of a French start-up called Enerstone, which is commercialising an active battery management system that can extend the lifespan of batteries by up to 30%.
The system monitors the health of each cell and redistributes loads so that “weaker ones work less than stronger ones, to extend the battery life to the benefit of the user,” explained Enerstone’s president and co-founder Alexander Chureau.
This month, meanwhile, a senior executive at Greensmith unveiled that its energy storage management systems had made it possible for lithium-ion batteries to beat lead-acid not just on performance but also on cost.
In one particular project, “the deployment of lithium-ion was half the price of lead-acid over the lifetime of the system, and it’s entirely due to software,” Leesa Lee, senior vice president, product management and marketing, told Energy Storage Report.
Lee cautioned that this eyebrow-raising result was partly due to the application involved. “The fact that it was true for this installation does not mean it is true for every installation,” she said.
“The economics and characteristics are entirely dependent on the use case.”
Nevertheless, such findings lend credence to a long-held view that management systems could be even more important than energy storage technologies themselves when it comes to reducing system costs.
Currently, energy storage technology developers are locked onto the objective of bringing product costs down to acceptable levels. Eos Energy Storage, for example, is touting battery systems that it says can provide power at USD$160 per kWh.
Challenges faced by battery makers
Developing a new battery technology and taking it to market can cost millions of dollars and the chances of success are small. Witness, for instance, the challenges faced by battery makers such as A123 Systems or Ener1.
And even Ecoult and Eos, to name just two companies currently arousing interest with promising products, are still a long way off achieving the scale and stability of battery giants such as Panasonic or the Automotive Energy Supply Corporation.
In contrast, since management systems are essentially software-based they can be developed, tested, produced and upgraded for relatively little cost.
“Since it’s not a materials-based science it’s much more straightforward,” observed Dan Brdar, CEO and president of Ideal Power, a power conversion system developer.
Another advantage, for technology-agnostic management systems at least, is that they make it easier to mix and match storage technologies to suit particular applications and environments.
In essence, with a good management system a project owner could choose relatively low-cost storage assets and let the software optimise the way they work together to address a given set of applications.
A measure of protection
Later on, if a given storage technology gets superseded by a more effective variant it should be easier to swap them over without affecting the system as a whole. This also gives the project owner a measure of protection against technology vendors going bust.
Another return-on-investment benefit of management systems, which are also being developed by companies such as S&C Electric Company, Growing Energy Labs Inc and Younicos, is they can help mitigate costs that fall outside the scope of storage assets.
Lee cites fire suppression systems as an example. These are required as standard in most battery storage projects, but their level of sophistication can vary greatly.
Greensmith’s management system, however, can be integrated with the fire suppression equipment so that if there is an emergency a controller can activate and manage it remotely, potentially avoiding damage to equipment and danger to personnel.
Finally, having a sophisticated management system might help give an energy storage project enough flexibility to cater for a wider number of applications. All these factors can weigh significantly on the business case for storage projects.
Improving battery economics
Thus, whichever way you look at it, “there’s a huge opportunity in improving battery economics by using them intelligently in addition to waiting for the cost curve to take effect,” said Lee.
Ideally, she said, management systems should soon be able to provide “this utopia where you’ve got extremely intelligent nodes out on the grid doing balancing and grid support, using storage as a buffer to support lots of different use cases.”
However, Philip Hiersemenzel, spokesman for Younicos in Germany, told Energy Storage Report that in some cases these advances in management system technology might have to wait for other parts of the grid to catch up.
“Storage is only smart when it optimises both towards the grid and, if applicable, towards the point of consumption or production,” he explained.
“Our controls communicate in both directions, but we haven’t seen any smart grid project in Germany do that too.
“In fact, we participated in smart grid pilot project a couple of years ago and provided really smart two-way controls, but had to dumb it down because the consortium wasn’t ready.”
Written by Jason Deign
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