Mr Hopper, Penryn

PV System: 3.78 kW Solar PV
Installation date: March 2015
Installation time: 1 day

Wattstor System Components:

  • 5 kVA Inverter Charger
  • Wattstor switch gear panel
  • 9 KWh Lead Acid Gel Battery Storage
  • Associated DC distribution

About the Customer

Mr Hopper is a retired engineer living with his wife in Penryn, Cornwall. As an active member of the local church, he has always championed renewable energy and sustainability, promoting it where ever possible. Mr Hopper’s aims were to utilize all his renewable energy to become as independent from the grid as possible.

How did Wattstor help?

In the spring of 2015, Wattstor designed and installed and a 6 kWh Lead Acid Battery system for Mr Hopper’s property. The system was installed in a day with no disruption to the home and the benefits of the battery were felt after day one! The customer monitored his consumption and generation for 40 days and found that the Wattstor could meet the demand of his 5kW load, which meant he does not have to import electricity through the night. On 35% of the days he reported importing less than 1kWh, costing just 15p for the days’ electricity from the grid.

After the installation, Mr Hopper compared his imported consumption from 2015 to the two previous years without the battery system. He has reported a 62% average reduction in imported electricity since installing the Wattstor system. This was remarkable, allowing the customer to reduce the energy cost while making the most of his renewable generation. After calculating the average storage against the daily evening consumption, Mr Hopper decided to add a further 3 kWh of storage in January 2016, to optimize his self-consumption, allowing even greater benefits.

At this time, a full system monitoring platform was installed and in May 2016, the system was reconfigured to function on the very latest version of operational firmware. This allows the system to peak shave by performing multiple cycles per day, again increasing self-consumption and reducing imported energy.


‘’My Wattstor can store up to 6kWh of power and can, within that capacity, meet demands of up to 5kW of electrical load – enough to get my home through the night without importing any significant utility company power. Indeed on 14 occasions during this monitoring period, my daily utility power import was less than 1 KWh at a cost of 15p!”

Richard Hopper
22 April 2015

Read More

The actual, measured, reduction in demand – imported electricity – is 62.1% over the period. I am now placing a load onto the National Grid of 37.9% of my average demand of the last two years. My experience mirrors that reported by the University of Exeter when they independently monitored the Wattstor prototypes in 2013. Interestingly, if my experience was repeated on all registered renewable energy storage systems (650,000 and growing) we could probably close down power stations instead of building new ones – especially the nuclear one at Hinckley C where the government is about to give £24bn to the French and Chinese to build for us!

Mr Hopper, Penryn
Mr Hopper, Penryn