Solar PV Overview

WHAT IS SOLAR PV?
Solar PV is a renewable energy system which uses photovoltaic modules on the roof of a building to convert light into electricity. Voltaic cells are made up of thin layers of semi-conducting material (usually crystalline silicon) which generate an electrical charge when exposed to direct light.

HOW DOES GRANT SOLAR PV WORK?
A Grant Solar PV module is made up of polycrystalline cells which consist of two or more thin layers of semi-conducting chemically treated silicon materials. The chemicals react when light hits the cell, creating an electric field across the layers, producing a direct current. The greater the light intensity, the greater the flow of electricity. This direct current (DC) is then fed into an inverter which changes it into a usable alternating current (AC).

WHERE CAN I INSTALL MY PV MODULES?
The location of the PV is vitally important. The modules must receive the maximum amount of day light possible, so it is not advised to install the modules in situation where surrounding buildings or trees may cast shadows. The best location for a PV solar module is on a south-facing roof. Grant have various mounting arrangements including on-roof, in-roof and flat roof kits, both landscape and portrait.

WHAT IS THE DIFFERENCE BETWEEN GRANT SOLAR THERMAL AND GRANT SOLAR PV?
Grant Solar Thermal involves water heating collectors which are very different from PV modules. In Solar Thermal water passes through pipes in the solar collector and the sun heats the water. This type of system will only produce hot water and installation will involve changes to your plumbing and heating system.
PV solar modules generate electricity, which is generally used to power appliances. Installing a Grant Solar PV system causes little disruption to your home because apart from a meter and switch which can be installed by your main fuse box, all the components are outside or in your loft.

WHAT HAPPENS WHEN THE WEATHER IS CLOUDY OR COLD?
Grant Solar PV uses light to generate electricity, so the modules still work when it is cloudy, although when it is overcast they are less efficient. When it is slightly overcast, the panels may produce as much as half the power they would in sunny conditions. When the sky is heavily overcast, this could reduce further. Temperature is less important than how much light there is. What’s more, a clear cold day is perfect, because PV modules operate better at cooler temperatures.

WHAT HAPPENS IF THE MODULES GET DIRTY?
Grant Solar PV modules are self cleaning when mounted at an angle of at least 15º. The amount of dirt on the modules depends on their location. If the modules are in a heavily silted area (e.g. under trees) the build up of dirt may reduce the power the panel generates by around 10%.

WHAT IS THE EXPECTED LIFESPAN OF A GRANT SOLAR PV SYSTEM?
Most solar panels have a lifetime of around 30 years. The PV modules supplied by Grant will have a twenty-five year performance guarantee.

HOW MUCH ELECTRICITY CAN GRANT PV IN A YEAR?
A 2kW Grant Solar PV System (approximately 16 modules) should produce around 1,600kWh of electricity per annum. To put this into perspective, 2kWh should run the lighting in an average household using low energy light bulbs for approximately one week.