A recently completed, retrofit solar PV installation for a customer based in St. Keverne, Cornwall.

A 3.9kW solar PV installation by GreenGenUK

This 3.9kW solar installation will generate a total of 3942 kilowatt-hours of electricity each year.

How it breaks down…

Due to the traditional nature of the property and the issues this would have raised with attaining an Energy Performance Certificate of a sufficient rating to receive the higher band of Feed-in tariff payment, GreeneGenUK proposed that the potential solar system be installed on an adjoining outhouse where the necessary EPC requirements would be met.

Our experience with designing and installing solar PV arrays on a wide variety of roof surfaces and sizes allowed us to propose a system that came close as close to the 4kW maximum domestic installation as possible. Due to restrictions with grid connections and export limitations, domestic solar PV installs can only exceed 4kWs in size with further permissions. Therefore, achieving a 4kW system maximises the financial returns on solar installations. In order to overcome space factors, this installation hosts 300W LG panels, as opposed to the 250W panels used in the majority of systems.

The system installed consisted of the following components:

13 x LG 300W MonoX black solar panels
1 x StecaGrid 3700W solar inverter
1 x Schletter slate roof mounting kit
1 x Rayleigh single phase generation metre

The Benefits

Switching to a renewable alternative, such as solar, provides numerous benefits to the customer. In the detailed proposal pack provided to the customer, we broke down all the likely advantages switching to solar would have.

The Feed-in Tariff

The Feed-in Tariff is a government-backed scheme, initiated to provide financial incentives to customers making the switch to solar. As part of the government’s wider push to lower carbon emissions, customer installing solar PV receive financial benefit for replacing grid demand with free, clean solar power. Payments are guaranteed and paid over a period of 20 years.

GreenGenUK estimates that this installation will provide the following Feed-in Tariff benefits:

Feed-in Tariff Generation Tariff benefit of £491 each year
Feed-in Tariff Export Tariff benefit of £95 each year

The Generation component of the Feed-in Tariff pays the customer, at a set rate, for every kilowatt-hour of solar energy generated by their system.

The Export component of the Feed-in Tariff is a deemed payment based upon the generator utilising 50 percent of the energy they generate and exporting 50 percent of their total generation back to the grid. As this component of the Tariff is deemed, consuming as much generated electricity as possible will increase the potential benefit.

Electricity Savings

Replacing demand from the grid with free solar energy will reduce a customer’s electricity bills significantly, particularly during summer months when generation is highest.

As electricity is always drawn from the closest source, solar generation reduces and replaces draw from the grid. We’ve estimated that this customer will see annual savings of £276 on their electricity bills.

Carbon Reduction

By substituting grid demand from harmful fossil fuels with environmentally friendly solar energy, the carbon output of a dwelling is drastically reduced. This 3.9kW solar installation will reduce annual carbon output by 1.7 tonnes.

GreenGenUK estimates, based on RECC and MCS guidelines, that this 3.9kW solar PV installation will provide total annual benefit of £863.

At this rate, and assuming electricity prices and interest rates remain the same, this system will pay itself back in 7.55 years and have a total lifetime benefit of £16,936.

An LG, 3.9kW solar PV installation

To find out more about this solar PV installation, or to see how a solar array could benefit your home or business, get in touch by:

Phoning the office on 0800 093 3299 and speaking with one of our renewable experts directly


Fill out the enquiry form found at the bottom of the case study and have one of the team contacts you