Integrating energy storage with renewable energy

RenewablesIntegrating energy storage with renewable energy is not a new concept and there are numerous cases of this technology being implemented. However, these are rarely for the commercial sector and are mainly used to
store renewable energy for use in peak shaving and load management.  This is mainly due to the intermittent nature of current renewable generation which make it difficult to predict how much energy there will be to store in an energy storage medium.

Virtue represents a unique solution that makes renewable energy reliable, allowing users to confidently save and store electricity generated from both voltage optimisation technology and renewable energy and switch to this at any time.


Making renewable energy reliable

Virtue uses the negative power feedback (back EMF)  generated by a Powerstar voltage optimisation system to divert saved energy into a storage medium. Energy generated from on-site renewable generation can also be diverted into the same storage medium.

By integrating energy storage with renewable energy a certain amount of energy will always be available in the batteries used, therefore the facility will always have enough energy stored so that when supply from the grid is interrupted unexpectedly, the building can still be fully supported.

Virtue also allows users to act as a Virtual Power Station, making informed decisions on when stored energy should be used, which will allows electricity costs to be significantly reduced.


Integrating energy storage with renewable energy

On-site renewable sources can be integrated with Virtue to provide maximum cost benefit, this includes:

  • Eliminating the need for inverters on renewables
  • Reducing the cost of initial renewable install
  • Increasing the return on investment levels of renewable installations
  • Storing energy generated by on-site renewable technologies

Consequently, by combining the unique design of Powerstar and renewable energy generation on a site, renewables can be made reliable and maximum cost benefits achieved.

Effects of Virtue on sites with renewable generation

The charts below show a typical commercial facility fitted with 200kW solar panels on a particularly sunny summers day. The graph on the left hand side illustrates a load profile when Virtue is not installed, highlighting that the direct effect of solar on the load profile is substantial, reducing the stores overall load consumption of electricity of 32.6%. However the majority of this load reduction occurs during non-peak hours, with solar only reducing the load requirement of the store during peak tariff times by 18%.

Solar Graph 1Picture1

Solar Line 3

The graph on the right hand side shows a typical load profile when Virtue is installed.

By storing the solar produced during the low and medial tariff periods it is possible to reduce the load to zero at peak tariff times. Therefore allowing the site to become completely grid independent.

The graph underneath shows Virtue utilising both negative power and solar power in such as way as to prevent the site ever demanding more than 100kWh per half hour of energy from the grid, as well as removing the site completely from the grid during peak tariff.


Virtue EV is a combined DC rapid/fast charger and energy storage system.
The solution has a 50kW rapid DC and 11kW fast AC charger and can be connected to a 16A grid supply.
It is able to deliver 106A DC rapid charge to EV cars.

The latest innovation from Powerstar, the Virtue EV system, has 80kWh of NMC batteries, a 50KW bi-directional Grid based Inverter with full UPS capabilities and a 6kW PV canopy providing some of the storage for the NMC batteries



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