Introducing the Key Energy MPowerTank


Key Energy MPowerTank


Comprised of a mechanical battery, engineered enclosure, and SENSSA Energy Management & Control System

The Key Energy MPowerTank combines a long duration flywheel from Amber Kinetics, with our Australian engineered, UTS validated above-ground enclosure, and in-house specially developed SENSSATM Energy Management Control System into a turn-key AC-coupled energy storage solution.

Energy Storage

A mechanical battery is essentially a long duration flywheel


Generic flywheel cut-out

The long duration flywheel stores energy via momentum in a spinning mass of steel. It consists of a large steel mass rotating around an axis.

It stores energy in the form of kinetic energy by accelerating a large multi-tonne steel rotor to high speeds of 150 Hz in a vacuum and magnetically lifted off the bearings to reduce air drag and friction respectively. The inbuilt motor uses electrical power to charge the system by rotating it faster. As the flywheel spins faster, it gathers force to store more energy. The motor becomes an electric generator when energy is extracted from the system as required, and slows down as more energy is extracted.

As there are no chemicals used to store the electricity, there is no risk of fire from the operation of the system. It also maintains full capacity throughout its useful life of 20-30 years.



SpecificationMPowerTank M24MPowerTank M32
Energy Capacity (kWh) modular, up to MWh24 32
Charge & Discharge Power Capacity (kW)88
Charge/Discharge Duration (hours minimum)34
Cycle Design Life (cycles) no daily cycle limit11,000
GHG EmissionsNone
Temperature (℃ operating) -20C to 50C
Round trip efficiency (DC to DC includes self discharge)~90% >86%
Max output DC current (A)13
DC Input-Output Voltage Range (VDC), nominal550 – 750, 650VDC
Self Discharge (Watts, Average over charge/discharge cycle)<100W (average), <350W (max)
Auxiliary Power (Watts, 240VAC Average over SOC range)<140W (average), <300W (max)
Full Power Response (mS)>80mS
Installation MethodAbove Ground
Noise (from electronics box)<65dB(A)
Modularity1 to 16 units (24kWh to 512kWh) per array, multiple arrays possible
Illustration and performance data are for reference only.
Materials and specifications are subject to change without notice.


Key Energy’s Smart ENergy Storage Solution for Australia (SENSSATM) Energy Management & Control System


The Smart ENergy Storage Solution for Australia (SENSSA) Energy Management Control System – is our proprietary Australian engineered and manufactured energy management control system. It operates and optimises the solution, controlling the power output of the solution for your home or business by connecting the inverter, power electronics, flywheel management system and other industrial grade monitoring and control hardware into a cloud-based 4G communications, and energy management software.

Most batteries come with basic battery management systems that only handle safety protection. Inverters can sometimes be programmed to schedule a once daily charge and discharge at set times. While this may be sufficient for a regular load profile, it does not work well when the customer has dynamic load profiles (e.g. 24/7 or night production shifts and operations, volatile peak electricity demand levels such as HVAC, motors, machinery etc.), when the wholesale market is particularly high priced, or for sudden high peak demand charges.

This means you may not see your bill reduce materially – despite investing in an expensive solar and battery system! To solve this problem, our SENSSA enables dynamic load following, manages peak charging issues with an AI and machine learning supported trading algorithm. Additionally, our SENSSA unlocks wholesale market selling (at an additional subscription cost) to support trading on the market to earn additional cash.

Energy Storage Control

Decides when and how much power to charge your batteries based on how much available solar and storage is available


Integrates Australian Standard compliant equipment such as inverters, smart meters, generators and load controls

Cloud-based web monitoring

Watch every second of how your system is operating via our web dashboard and monitoring system

Load prediction & control

Combine thousands of data points together with our AI and Machine Learning models to predict and control your electricity use

Wholesale Market Ready

Automatically sell your excess energy to the wholesale market at the right price for energy market arbitrage (pending Regulator Approval)

Advanced Functionality

Key Energy’s SENSSA unlocks advanced control features and functionality for your whole energy system

SENSSA Additional Functionality

Scheduled charge/ discharge
On request
Off-grid / Backup Power
Load Following
Time of Use Bill Management
Demand Charge Reduction
AI & Machine Learning
Predictive Analytics
Energy Arbitrage
(Wholesale Pricing / VPP)

Off-grid MPowerTank Real Time Operations Dashboard via our SENSSA Energy Management & Control System


Our industrial grade SENSSA Energy Management & Control System provides a real-time view of your power system, with more detailed information and customisable to your needs. This live real project data is of the pilot off-grid system in Armidale, NSW. Learn more about the project.


Engineered Above Ground Enclosure


The Amber Kinetics M32 steel flywheel is incredibly safe, and has been designed with safety as a foremost principle, resulting in no history of accidents or catastrophic failure for over 15 years and millions of operational hours. However, we at Key Energy treat safety as our top priority and endeavour to independently verify all claims and mitigate any catastrophic impacts to an acceptable level. At full 32kWh speed, the rotor is spinning at c. 150 Hz, so any risk of catastrophic failure (steel ruptures) must be mitigated to protect people and property.

Key Energy collaborated with University of Technology Sydney (UTS), generously supported by the NSW Government TechVouchers grant program, to validate our safety enclosure design for the 32kWh flywheel. Using the latest in Finite Element Analysis techniques, their Centre for Built Infrastructure and Research (CBIR) experts in concrete and civil engineering created a high fidelity model and ran dozens of simulations through their supercomputer to validate that the Key Energy engineered design would keep people and property safe in the event of a catastrophic failure of the rotor. Proudly made in Australia, using all Australian structural steel and special grade concrete and materials, our above ground enclosure will last as long as the flywheels, protecting them from the weather and animals, and protecting people and property from risk of harm.

24 kWh Enclosure
For the 24kWh model, whilst the Amber Kinetics M24 (24kWh capacity) steel flywheel is the same machine, it runs at significantly less speed and therefore placed under less material stress, hence is much safer and lower risk than the M32 (full 32kWh capacity). Accordingly there is a reduction in the enclosure requirements.
32 kWh Enclosure
Our latest commercially available 32kWh enclosure comes in primed or rust-finish. Many of our customers choosing the rust-finish aesthetic to fit their property landscape.



What’s Included in the MPowerTank System

  • Flywheel (Amber Kinetics’ M-series flywheel and e-box, vacuum pump and accessories)
  • Above-ground enclosures (24kWh or 32kWh models available)
  • 20kW Inverter – 3 phase, multi-mode (off-grid and on-grid/generator ready), hybrid (solar + battery) inverter
  • Key Energy SENSSA Energy Management and Control System (Hardware + Software)
Armidale express

Request to see a local MPowerTank

Contact us and mention that you would like to see a local MPowerTank system so we can arrange with your nearest demonstration site!

Early Adopter Offer

If you are the first client to install a mechanical battery in your area and are open to future customers taking a look at your system, you will be able to access a variety of benefits for your project. Simply request a quote and tell us where the project is, and if you’re the first in the area we’ll make the offer to you automatically!

Key Energy’s Design to Discharging Process


Initial enquiry, design meeting, and site inspection
1-2 weeks

Give us a call on or fill in an Enquiry Form to begin the journey of using more of your own power. Tell us about your home or project, energy or lifestyle goals, and ideally have some data available for us to design your project correctly. If your project is simple and you just want one of our MPowerTanks, we will explain the system in detail and answer any questions you may have. For complex projects we will assess the data to give you a high level solution design proposal and rough order of magnitude project costs.

If you agree to continue, one of our technicians or representatives will visit your proposed site to collect additional data if necessary, confirm access and other installation requirements, update the quote if necessary, and talk you through the draft solution design.

Final Design and Contract
1-2 weeks

With an agreement on all the project details you will be provided an accurate final technical plan with scope of works, solution outcomes, possible variations and a total cost of work, as well as areas that could risk fee over-runs, though we try to minimise these as much as possible. Once you understand and are happy with the project proposal, you will be able to sign the contract to begin the delivery process.

Site preparation (e.g. slab preparation) and delivery
2-6 weeks

If you are still building your property or have no pre-existing base slab, then you will need time to prepare the concrete slab to our standardised specification, or we can provide a pre-cast concrete slab. If you have an existing concrete base and location on site to use, we will confirm that it is suitable for the loadings of the MPowerTank. Stock is kept on-shore in our Sydney factory and warehouses in capital cities in Australia, but can be shipped to order to any port destination as required. We generally arrange delivery that suits you or your client’s timing and minimises expensive logistics costs. We can have a unit shipped within the week if you have everything ready.

Installation and Commissioning
2-3 days

Before the system is installed Key Energy with prepare all material, installers and certificates before the project starts. Key Energy keeps local stock on hand so depending on location and logistics, delivery can be arranged for a suitable date. Installation usually takes 1-2 days.

Commissioning is the process of turning the system on and providing power to your home or business, and running a series of tests to ensure the system is working. Key Energy performs and monitors a full cycle test, both locally and with remote support, and once tested, hands over the system providing all information on how to operate, troubleshoot and monitor the system

Maintain and enjoy your MPowerTank

Key Energy will remotely monitor your system for any alarms or faults. We provide SMS alerts to a designated number (or up to 12 email notifications) for any critical faults that need on-site attention. We’ll also provide you the number of a dedicated support engineer. We remind you for your scheduled maintenance, comprising an annual vacuum pump oil inspection, and dust filter cleaning. We continue to provide ongoing support and maintenance to ensure the system is operating as good as it did brand-new.


Get the latest product updates and upcoming events from our blog.


What is the weight of the M32 Flywheel?

4.8 tonnes, with a 2 tonne rotor. The enclosure is 200 kilograms for 24kWh and <4 tonnes for the 32kWh flywheel

What is it made of?

Steel (carbon levels and type not disclosed to us).

How fast does it spin?

Between 50-150 Hz, or 3,000 – 9,000 RPM.

Where are they manufactured?

The flywheel is designed in USA and manufactured in Philippines

The SENSSA and above ground enclosure are all designed and made in Australia.

Who is it best suited to?
  • Diesel generator replacement or fuel reduction solution
  • Off-grid power
  • Rural properties
  • Agribusiness customers
  • Commercial and industrial
  • Farms and irrigation pumping 
  • Virtual Power Plants (VPP)
Can I use them for off-grid applications?

YES! Our system is purpose designed and built to work in the harsh Australian climate both on-grid and off-grid.