Skip to main content
Recite me
This project ended in January 2019 and is now closed.Dismiss

Solar Storage

Funding mechanismNetwork Innovation Allowance (NIA)
DurationApril 2015 - January 2019
Project expenditure£865,000
Research areaEnergy Storage and Demand Response
  • South West

January 2019

Following the dissemination webinar, the Solar Storage project is now closed.   The slides from the webinar and the final report are available from the “documents” section of this website. 

Show all updates

January 2019

Following the dissemination webinar, the Solar Storage project is now closed.   The slides from the webinar and the final report are available from the “docu…


  1. Quantify the potential value to network operators and others of integrating storage with DG.
  2. Use real-world operation of integrated utility scale storage: generation system to provide data to regulators and potential investors.
  3. Demonstrate safe, reliable operation of the system under operational conditions.
  4. Determine market interest in second hand batteries and the practicalities of their sale and removal.


Integrating storage with renewable generation offers a route to addressing some or all of the following issues:
(i) Renewable generation does not predictably match peak local demand.
(ii) Renewable generation is often ‘spikey’, which can introduce short-term impacts on grid voltage or other quality of supply factors.
(iii) Unpredictability, lack of control mechanisms and power quality mean grid operators use very conservative rules to allocate grid connections.
(iv) Grid operators have to introduce new equipment to manage power quality, a service which could be provided by operators of utility scale renewable installations.
(v) Without the ability to respond quickly to local surges in load, grid operators manage network capacity within tighter limits than might otherwise be possible.
(vi) Introducing two or more active storage or quality management devices onto the same HV circuit may cause them to interact with each other and have a negative impact on power quality.


A battery and control system will be integrated with a 1.3MW PV array connected to WPD South West’s 11kV network. Analysis of the detailed data set created by carrying out a set of well-defined use cases will form the technical core of the project. The use cases will demonstrate:

  1. Sale of energy stored in the battery for a higher price;
  2. Better matching of generation profiles to demand profiles;
  3. Use of storage to peak lop PV generation above a (dynamic) power threshold;
  4. Import electricity from the grid at times of low demand;
  5. Absorption and supply of reactive power to help manage the network voltage;
  6. Reduced connection capacity requirement per MWp generation capacity;
  7. More predictable PV output through smoothing PV's steep ramp rates;
  8. Raise or lower the export power threshold depending on thermal or voltage constraints;
  9. Show the control system allows smart co-ordination of multiple storage systems;

Analysis of the data will quantify the potential value of each use case.

The project team will work with stakeholders and project participants to propose potential changes to regulations, grid code, balancing mechanisms etc. to allow reward for investment in storage.


We recently held a final dissemination webinar on the 31st January 2019. You can view the full webinar below, or click here for a copy of the webinar slides.  


  • 1) Complete Design of BESS.
    2) Procure equipment, install and commission. 3) Run trials and write report.
    4) Identify changes necessary for participation on the Balancing Mechanism.
    5) Conduct a battery sale process and remove the battery

  • Phases 1 to 4 above completed safely, on time and on budget. All usage cases are investigated and a comprehensive analysis of all data collected undertaken. Useful and applicable conclusions generated from the data analysis. Effective communication of the project’s results and conclusions to the UK renewable energy and power distribution community. Successful engagement with stakeholders, influencing the development of relevant governing mechanisms such as the grid code or balancing mechanism (BM).

  • A manual for the business case for future solar energy storage systems will be produced covering:

    • A control system for this application that only imports electricity when intended.
    • The size of battery and clipping probability required for a given level of peak lopping.
    • The fraction of the battery used and the typical duty cycles, informing design requirements.
    • Best operation strategy and optimum revenue streams. Learning will be shared by presentations at the LCNF conference and DG forums, and a final report.
    • {{update.title}}