EMMA - Electrical Distribution Unit

EMMA (Energy and Micro-Generator Manager) controllers enable you to maximize the energy you generate through eliminating waste, controlling its export and storing any surplus.


EMMA’s key benefit comes from diverting excess production away from being exported to the grid, instead putting it to immediate use in the home/business, helping you to save money.


For example it sends the surplus electricity to heat your water NOW - while surplus electricity is available - rather than allowing it to be exported, only for you to have to buy-in electricity from the grid later in the day.

How Does EMMA Work?

The diagram below explains how the unit works:

EMMA - Electrical Distribution Unit EMMA - Electrical Distribution Unit

Electricity from your microgenerator (M) is used onsite first.
If (M) is greater than (A), the surplus electricity is diverted to (S)
If (M) is less than (A), grid-electricity is used to supplement (M)


The Result
EMMA balances the demand for electricity in your home with that being produced by your generator so closely that your electricity meter may at times come to a complete stop.


Suitable for installation alongside any renewable energy generation system including wind turbines, Solar PV , biomass boilers and hydro generation systems.

EMMA's Functions

Optimisation of output utilisation:

Diversion of  surplus power from thegenerator to one or more thermal stores (immersion heaters, storage heaters, swimming pools etc.). While doing this EMMA holds electricity export at or close to zero. This function is standard to all EMMA units, including EMMA for Home, and with or without the Export Control (EC) add-on.


Export control:

The EMMA unit can limit electricity exports from your generator to whatever your DNO (District Network Operator) permits. This allows you to grid-connect generators where otherwise it would not be permitted or may require expensive network upgrade costs., and at the same time enables you to avoid expensive Network Upgrade Costs. The export control function kicks in when the thermal store(s) are 'full' (have reached their target temperatures) or are otherwise not available and surplus electricity needs to be managed in other ways to prevent excessive export. This is the export control (EC) function provided by EMMA's optional EC add-on.


Grid voltage stabilisation:

EMMA keeps the supply voltage below the DNO's permitted limit to prevent the inverters tripping.  This avoids unnecessary inverter trips, saves you money and prevents power outages.

Main Benefits Of EMMA:

  • Optimise the financial return from your investment in renewable energy:
    • Use all your surplus electricity onsite - up to 70% more than without EMMA.


Efficiency and Flexibility
Hot water - exactly when you need it

  • Better control of water temperature - so you save money
  • Reduces heat loss from your hot water cylinders by up to 20% - so you save money
  • Holiday mode - maximise your income from feed in tariffs when you are away



  • EMMA outperforms other devices. Other devices may actually increase your energy bills costing less than a solar thermal system and saving you more over time


Network stability

  • Avoid network upgrade costs
  • Ensure compliance with relevant harmonic current limits
  • Reduce network disruption and overvoltage events
  • Reduce network maintenance costs


Example Installation

Get In Touch: