This product is snake oil. The sales blurb from another website goes like this:
The Matt-e Solar PV+ unit is an over-voltage protection device that can increase the amount of total power you can generate from a PV installation in areas of high nominal mains voltage.
Solar PV inverters generate at a higher AC output voltage than the nominal grid supply in order to be able to export onto the grid. The increase is typically 4-6% of the nominal voltage available. If at peak generation times the nominal mains voltage is above 246Vac, the solar PV inverter has to shutdown as part of its over-voltage protection settings, losing you potential revenue from solar generation.
A Matt-e Solar Plus unit can increase solar PV output generation by up to 20% as it keeps your system generating for longer periods by reducing the supply to the Solar PV inverter. The device can be fitted to both new and existing solar PV systems. Running the solar PV inverter within its input DC voltage window also reduces heat build-up and stress and helps to prolong the working life of the inverter. The typical return on investment is within 2 years.
The truth is…
Inverters can shut down if they measure a high mains voltage. However, it has to be considerably higher than normal. If the voltage at the inverter’s grid connection is high then it is one of two things
- Inverter supply cable under-sized – particularly where the inverter is a long way from the incoming electricity supply. Rather than throw £1000+ at the problem, get the installer back to fit a more appropriately sized cable, or pay someone else to do it.
- Grid voltage too high – this is more common. The statutory limits for the grid voltage in the UK is 230V give or take 10%, therefore the upper limit is 253V. If your grid voltage creeps higher than this then your Distribution Network Operator (DNO) is obliged to remedy it at their expense. You can find out who your DNO is by visiting this page from OVO’s website: https://www.ovoenergy.com/guides/energy-guides/dno.html