BMW Rolls Out Massive i3-Powered Energy Storage System – 22 or 33 kWh

JUN 22 2016 BY MARK KANE 22

2017 BMW i3 Battery

2017 BMW i3 Battery

BMW has introduced an energy storage system for residential and commercial applications from the Electric Vehicle Symposium & Exhibition 29 in Montreal this week (or EVS 29 for short).

BMW is the second German automaker this year to announce plans for the retail ESS space, joining Daimler/Mercedes-Benz Energy, who started actually delivering 2.5 kWh residential systems this past April.

For BMW, its ESS is based entirely on the i3 battery system (which appears to basically be a wall-mounted battery pack) and can work with both new or 2nd life batteries (retired form the cars).

The advantages (and distinctions) of BMW’s package are obvious, using an entire pack allows for massive capacity right out of the gate unlike the other automaker’s systems, and (in theory) also allows for the most inexpensive product (per kWh) as the re-purposing of the packs from the automotive application is straight forward.

“With a battery storage system electrified by BMW i our customers can take the next step towards a sustainable energy lifestyle. Coupled with the home charging and solar energy programs, the system enables BMW drivers to embrace holistic sustainability beyond e-mobility,” said Rob Healey, Manager of EV Infrastructure for BMW North America.

BMW i3 battery: New or used, it is ready to be put to use for energy storage

BMW i3 battery: New or used, it is ready to be put to use for energy storage

Nissan also introduced its own “2nd life” storage system – xStorage a month ago in Europe, but choose to re-house individual modules in a new package – pricing its 4.2 kWh unit at €4,000/£3200 ($4,500 USD) installed.

In this case, BMW’s battery was integrated into a complete energy storage system by German company BECK Automation.

BMW states that batteries are plug and play modules and that the whole system is ready to handle solar installations right out of the box, offset peak energy usage, and provide backup energy supply during power outages.

There is no info about pricing or number of modules that could be combined into one system yet, but as the system is utilizing a single wall-mounted battery, it can be 22 kWh or 33 kWh (new 94 Ah cells).

For additional information and some commentary on the BMW ESS, check out Tom Moloughney’s blog post here.  Full BMW press release is also below.

BMW Press Release:

“… BMW i, a leader in innovative electromobility since 2011, announced a stationary energy storage system solution integrating its BMW i3 vehicle battery at the Electric Vehicle Symposium & Exhibition 29, making it the first automotive manufacturer to utilize a complete automotive high-voltage battery for energy storage. The battery storage system electrified by BMW i, enables customers to more fully realize their commitment to sustainability – and to take the next step towards energy independence. With this system, which integrates seamlessly with charging stations and solar panels, customers can offset peak energy costs and also enjoy the added security of an available backup energy supply during power outages.

The i3's battery tray

The i3’s battery tray

The system utilizes BMW i3 high-voltage batteries and can be expanded to incorporate 2nd Life Batteries as they become available in the market. This strategy will extend the useful life of the battery for the owner, even beyond in-vehicle use.

“The remarkable advantage for BMW customers in using BMW i3 batteries as a plug and play storage application is the ability to tap into an alternative resource for residential and commercial backup power, thus using renewable energy much more efficiently, and enabling additional revenues from the energy market,” said Cliff Fietzek, Manager Connected eMobility at BMW of North America.

Premium electromobility converging with sustainable resources to optimize energy efficiency at home.

The concept announced today at EVS29 is the first market-ready home storage system using a repurposed (i.e. 2nd Life) automotive BMW i3 high-voltage battery integrated by BECK Automation (Wuerzburg, Germany). The battery storage system electrified by BMW i can be equipped with new or 2nd Life Batteries. This holistic approach underlines the sustainability strategy that has characterized BMW i since its inception.

This system can enable energy produced from solar panels to be used more efficiently. It can be charged during the day, taking advantage of the energy that may otherwise be underutilized while customers are typically away, to support the overall energy efficiency of their home. Because typical daily household energy usage in the US is between 15-30 kWh1, the battery storage system electrified by BMW i with its 22 kWh or 33kWh capacity is ideally suited to operate a variety of appliances and entertainment devices for up to 24 hours on its own.

BMW i3 Battery opened up

BMW i3 Battery opened up

The battery storage system electrified by BMW i and Battery 2nd Life.

The battery storage system electrified by BMW i can incorporate used BMW i3 batteries, expanding the holistic sustainability of BMW i and supporting the next phase of future energy efficiency and independence. Because the electric draw is much less at home when compared to automotive usage, this storage system is an ideal application for a retired BMW i3 battery and ensures that the repurposed battery will offer many additional years of service, affirming the BMW i commitment to sustainability.

The “plug and play” nature of the BMW i3 battery application in this system is a key element in its design. Following in-vehicle usage, the BMW i3 battery retains most of its original capacity, thus continuing to offer years of emissions free power storage and expanding the sustainability concept beyond the individual vehicle life.

i3 Battery Pack

i3 Battery Pack

Intelligent interface that maximizes energy utilization.

The battery storage system electrified by BMW i ensures that the energy is utilized in the most efficient way possible. Utilizing real-time energy readings, the system can measure the available energy supply and demand, making the necessary calculations to determine the optimal time to charge or discharge the system. This approach minimizes energy waste, effectively reducing energy costs on a day-to-day basis.

The battery storage system also includes a voltage converter and power electronics to manage the energy flow between renewable energy sources, the house interface, and the Li-Ion high-voltage battery from the BMW i3. The system has been designed to be perfectly integrated into the house energy supply chain. The battery storage system electrified by BMW i is ideally sized so it can be conveniently placed in the basement or the garage of a detached house, where the stored energy can either be used for electrically-operated devices in the home or for charging the battery of an electric car.

Individual battery storage systems are key to enabling privately generated renewable power to be used directly on-site instead of being fed into the local power grid. By combining an eco-friendly power supplier with the convenience of the battery storage system electrified by BMW i at home or at a small business, our customers will be able to store renewable electricity and then use it at an ideal time to augment energy from the grid during periods of higher pricing, effectively reducing energy bills.

BMW i3 Battery

BMW i3 Battery

The battery storage system electrified by BMW i – years of study and research.

BMW i, a world leader in sustainability, has dedicated years of extensive practical studies and research together with Universities, National Laboratories, Utilities and Industry partners to maximize residential energy efficiency. The high-voltage batteries developed for the BMW i3 have already demonstrated their high potential for secondary use as a stationary power storage in numerous research projects. Long before the launch of the BMW i3, it was clear that the batteries would have an exceptionally long life and could serve a useful purpose in enabling electric driving both within and outside of the vehicle. In 2011, batteries which were previously used in the MINI E test fleet were successfully implemented in a stationary project. Together with the Federal Ministry of transport in Berlin, the project demonstrated that an energy positive home environment with a battery system is possible.

In 2013, BMW and the University of San Diego installed a micro grid application with Battery 2nd Life MINI E batteries. In 2014, BMW integrated high-voltage batteries into a stationary storage system in Hamburg. This project serves the energy supplier Vattenfall as a power buffer for fast charging stations, aiding by storing solar power and helping to stabilize the electric grid.

In 2015, NextEra, the leading American energy producer and distributor of clean energy, signed the largest contract in automotive history for the delivery of 20 MWh of Battery 2nd Life automotive batteries. These batteries were sourced from the BMW ActiveE test fleet in the US and from early BMW i3 vehicles. NextEra will operate them in various industrial sized stationary electricity storage systems.

Another step forward for BMW i 360° Electric and the sustainability lifestyle.

The battery storage system adds to BMW i 360° Electric, an array of lifestyle offerings designed to optimize convenience and sustainability of the e-mobility lifestyle for BMW i and iPerformance customers.

BMW i 360º Electric encompasses products for home and public charging, assistance services, and flexible mobility. Moreover, BMW has partnered with experts in the field of electric mobility to provide its customers the best solutions available on the market to optimize their overall EV driving experience. Therefore, not only does 360º Electric allow for a convenient and easy transition to electric driving, but it will also provide customers access to an energy-conscious, sustainable lifestyle.

“With a battery storage system electrified by BMW i our customers can take the next step towards a sustainable energy lifestyle. Coupled with the home charging and solar energy programs, the system enables BMW drivers to embrace holistic sustainability beyond e-mobility,” said Rob Healey, Manager of EV Infrastructure for BMW North America.

ChargeForward – a key component to the battery storage system electrified by BMW i.

BMW is conducting a pilot study into the relationship between home electric vehicle (EV) charging and the energy grid, together with Pacific Gas and Electric Company (PG&E), whose service area covers Northern and Central California. Working with a group of nearly 100 BMW i3 drivers in the San Francisco Bay Area, BMW i ChargeForward is demonstrating how intelligent management of EV charging can contribute to optimizing electric power grid efficiency, and thus is expected to reduce total cost of electric vehicle ownership. The study has two parts: a managed charge pilot program involving BMW i3 owners and a Battery 2nd Life energy storage system. In the managed charge pilot program, these BMW i3 owners allow BMW to delay or interrupt the charging of their vehicles by up to an hour, based on requests received from PG&E when grid loads are at their peak. The program also includes a “second life” for used MINI E batteries, by repurposing these batteries into a stationary solar-powered electric storage system located at the BMW Group Technology Office in Mountain View, California.”

Categories: BMW, ESS

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22 Comments on "BMW Rolls Out Massive i3-Powered Energy Storage System – 22 or 33 kWh"

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Do they still use an external a/c compressor system to cool the batteries.

Tesla is going to add to their storage system, production. So if BMW will sell large batteries like that then it will make sense to also sell solar panels to charge these large batteries. The only reason I see for using such a large battery is to charge the car when it is home. Most house holds around the whole world do not use so much electricity per day. So maybe what BMW is thinking is that they will provide a way to compete with the free supercharging of Tesla. How ever the cost of these batteries and enough solar panels and some electronics like a charger and a converter will add up. The Tesla and SolarCity solution will be much cheaper and Tesla will be able to provide a variety of combinations. They will be able to sell the car, the storage in the form of batteries and the production in the form of solar panels. In addition Tesla will provide the option of supercharging too. So it looks like BMW can see that coming and wants to get in the game too with these large batteries. Let us hope that others like GM Ford etc can do the… Read more »

I was planning an 8kw PV system on my roof with 3 Powerwall batteries in the next couple of years so to hear that this size battery will soon become available is music to my ears !

The size of this battery should enable many to virtually do away the need to buy much electricity from utilities (no doubt they will try to put up a fight) with any luck.

This can only be good for competition and I look forward to others offering similar size ESS’s.

This is all well and good for us electricians. Especially those of us who practice what we preach (utilize home solar) and are tired of working with flooded lead acid batteries.

The private utilities hate this stuff even more than residential solar. I look forward to disappearing from the grid 11 months out of the year.


All fine and dandy for automakers to do this. But give us V2H options already. Why by another battery pack or repurposed battery when we should be able to plug our 50%+ unused battery into the house to offset usage from 5pm-12midnight? Then recharge to 100% at super off peak levels?

Love the ideal of Reuse/Recycle, but they keep leaving out the REDUCE part and leveraging existing (well, because it doesn’t earn them any money, does it….) Green only to a certain point.


@Alan – 8Kw system is cutting it close for off grid battery with EV attached. Even hear in temperate sunny San Diego.

Am hoping so !

I am planning on buying the Sunpower X21 (X22 if they arrive here in the UK by then) Signature Black panels, the V2H system that Nissan has should arrive here next year as they are already piloting them around Europe.

I reckon within 3 years the cost of the whole system would pay back in approx 7 years which is pretty good.

In San Diego you have 2978 hours of sun shine per year. So with just 12 solar panels 250 watts each you will be able to produce 8934
kWh per year. The average house hold in San Diego us about 6000 kWh per year. So you are left with 2934 kWh per year to charge your car. Divide that by 365 days the you get 8 kWh per day for the car. Let us suppose that you use 150 watts per mile every day. Then you will be able to drive 53 miles every day from the sun. To store this 8 kWh you will need 8 kWh PLUS another 8 kWh for the night use of the house. So 8 kWh of batteries is not enough. The calculation show 16 kWh is the minimum. To be practical 24 kWh is good. 33 kWh is even better.

With a solar array pointed at a noon sun you are generally assumed to get 1000 Wh/sqr(m) solar power. San Diego gets ( around 5.8 Wh/sqr(m), which works out to about 2100 hours of noon solar equivalent for a fixed flat plate collector.

The average residential electricity use in the USA is nearly 11,000 kWh/year (, but 6,000 kWh looks about right for San Diego.


For reference, we have 4kw PV that’s ideally suited SW for max peak power production 12n-6pm — with TimeOfUse in place before EVs, we were at Tru Up about 500kw overproduction for 3800ft home. With one EV 10,000 miles @ 5m/kwh = 2000 kwh yearly demand at super off-peak rates essentially was a no brainer as it got to 80% net neutral.

Then we added a second EV at 12,000 miles anticipate and now significant consumers–and added a pool this summer too, so we’ll be really wishing for a 10kw array (alas, no rooftop room for such).

I take it you have no batteries. A grid tied system is that right?

Wall mounting a 450lb pack? It should be floor mounted for simplicity.

Bury it under the ground.

A bit like a water boiler for a bath, no big deal.

This is what I want to do. Take a complete, intact battery pack from a wrecked EV and connect it directly to an inverter in my house. The BMS and everything is already in the pack, all you have to do is know how to interpret what it’s saying. I really hope vendors are showing appropriate inverter systems at Intersolar next month for this to happen.
I agree that mounting system looks, shall we say, non-ideal. I would support the dead weight on the floor but anchor it to the wall for stability and earthquake safety.

It’s hideous. Come on BMW, who let this out the door? It looks like they hung a back off the wall and used a bit of crudely bent sheet metal painted blue with a BMW logo.

What were they thinking? It’s something you want to show off, not hide.


It’s a battery pack. Our hideous bikes and other garage flotsom hides the wall hung things quite effectively.

Why does Nissan not offer this for their leaf?
Got a 2012 leaf would be a great option for me to get the old battery pack out of the car when finished with (70000 miles) and put the pack at the side of the wall and get the excess solar to charge up the pack for night time.
Cmon Nissan do the right thing and follow bmw idea

This is much cooler and smaller. 28 kwh 🙂

Ich sprechen nur ein bisschen Deutsche.

I’m impressed

But where will the bats live?