The sales pitch of a flow battery is that you simply need to replace a few filters, a pump or two over time, and the thing will run for as long as the container holding the battery is protected from the elements. So you get amazing flow battery warranties of 20+ years, but what’s the piece of paper worth if the manufacturer joins the graveyard of technology companies? In this case, you learn the term “bankable”.

One way to protect against the risk inherent with new ideas and companies with smaller bank accounts is to find a larger company that is an expert at assessing risk. Enter the insurance industry.

Munich Re, a German re-insurance group with €49.1 billion in global revenue in 2017, is now offering a 10-year insurance plan on the performance and hardware of ESS’s iron flow battery. The reinsurance company developed a “Project Cover” that backs up ESS’s already existing 20,000+ cycle lifetime (assuming one cycle per day 50 years).

The two pieces of hardware offered (an 8 hour and a 4 hour version of the 400 kWh capacity) by ESS on their website are noted below:

Download the EW ™ 50kW/400kWh Data Sheet (pdf)

50kW/400kWh Data Sheet (pdf) Download the EW™ 100kW/400kWh Data Sheet (pdf) The battery can be at full power in less than 1 second, per documentation. The larger unit’s specifications: The units are delivered to site in standard 40 foot shipping containers. Re Munich is offering the coverage to other energy storage companies as well, and states the goal of the coverage is to de-risk to financial models of project developers from greater than projected operations and maintenance costs: For example, if the repair or replacement costs of defective or weak battery modules exceed a predetermined amount, the insurance then covers the rest. Manufacturers can thus unburden their balance sheets. Munich Re believes that since their product will cap repair costs, and will be seen as a feature to drive sales of specific hardware. The insurance cover is primarily aimed at major projects, such as those to ensure grid stability or to cover peak demand periods. In a second phase, the product will be introduced for the mobility market, for example to insure performance of batteries in electric vehicles.