Prudent Energy’s Vanadium Flow Battery

Table of contents

A 2012 study conducted by Lux Research predicts that vanadium flow batteries could capture about 17 percent of the energy grid storage market by 2017, representing about $5.4 billion in potential revenue. This assumes that developers can reach a target of $750 per kilowatt-hour for a fully installed system by 2017. One company that seems to be an established leader in vanadium flow batteries is Prudent Energy.

About Prudent Energy

Founded in 2007, Maryland based Prudent Energy employs over 170 professionals at a number of locations in the US, Canada, and Asia. The Company taken in just over $50 million in funding so far from firms such as Draper Fisher Jurvetson, Mitsui Global Investment, Northern Light Venture Capital, and Sequoia Capital.


Prudent Energy designs, manufactures and installs the patented Vanadium Redox Battery Energy Storage System (VRB-ESS) an advanced vanadium “flow battery”. The VRB-ESS is distinctive from other energy storage systems in several respects, including the ability to charge and discharge 100% of its capacity, for almost an unlimited number of times without damage. The entire system runs at low pressure and room temperature, anywhere from 50 to 90 degrees Fahrenheit. And because the electrolyte doesn’t degrade, it is reusable – an asset that retains its value for the owner. Storage duration in a VRB-ESS thus becomes simply a function of the amount of electrolyte in the storage tanks.


In other words, unlike Zinc-Bromine or Lithium-ion batteries, a VRB-ESS® affords completely independent scaling of power and energy. Prudent Energy has over 60 patents worldwide encompassing their core cell stack designs, electrolyte composition, system designs, as well as several application patents including use with wind farms, off-grid applications, and smart grids.


In April 2012, Prudent brought online the world’s largest flow battery installation for Gills Onions and published a case study on the success of the project. Prudent Energy owns and operates the VRB-ESS® in return for a share of the energy savings resulting from the project. Since that announcement, it has been over two years and Prudent has yet to issue any press releases regarding their progress. As of 2011, Prudent had over 50 systems installed at utility and commercial customer site in 12 countries around the world including emerging markets such as China, Indonesia, and India. If the company has been aggressively expanding since then, they should now have captured some meaningful market share. It would be great to see some updates from this well-backed grid storage startup.


Leave a Reply

Your email address will not be published.

  1. A good story as I have a share in Bushveld minerals who have found large resource of Vanadium in South Africa.

    1. Thank you for the comment Martin. Here’s a good article from the BBC on vanadium in general:


      We mentioned a vanadium mining company in a previous article as follows:

      Largo Resources (OTCPK:LGORF) is in the final stages of developing their Maracas Vanadium project in Brazil with production to begin this quarter. The company claims to have the highest grade vanadium deposit in the world. This means a low cost of production since high grade vanadium has a much higher recovery rate due to less energy required and lower reagent costs. Largo has a 6-year take-or-pay agreement with Glencore, the world’s largest trader of vanadium, for 100% of their output.


      We haven’t heard of Bushveld minerals but will take a look. If they aren’t yet producing the question is how much time and money are needed to produce and where will the money come from.

  2. Just came across another vanadium flow battery company: Invinity Energy Systems.
    It is listed in UK, ticker: IES.L.
    As for Prudent Energy VRB Systems – it seems they no longer exist ..

    1. We’re not surprised to hear Prudent Energy VRB Systems pulled a Sonny Bono. Many of these small new-tech energy storage systems don’t turn out to be commercially viable. IES.L is a miniscule firm and it’s not worth the risks from where we’re sitting. Thank you for the heads up!