HavMain is a MCS registered installer for PV Solar systems. We can design, install and commission solar PV systems throughout the South West of England including Devon (Torquay, Paignton, Brixham, Totnes, Plymouth, Exeter), Somerset (Taunton), Cornwall and surrounding areas.

With the EU looking to deliver a target of 20% of energy coming from renewable sources by 2020, the UK is committed to contributing towards it through encouraging home owners, businesses and communities to invest in energy saving initiatives such as microgeneration technologies.

Working towards this target could provide £100 billion worth of investment opportunities and up to half a million jobs in the renewable sector by 2020.

HavMain are MCS accredited (Microgeneration Certification Scheme), meaning we are a registered installer of solar photovoltaic (PV) systems.

Solar PV systems capture and convert sunlight into electrical power using a thin layer of semi-conducting material, usually silicon, encased between a sheet of glass and a polymer resin.

When exposed to daylight, electrons in the semi-conducting material become energised and flow through the material generating a direct current (DC).

The DC is carried through wiring to an inverter which converts the current to 240V alternating current (AC) so it can be connected to the main electricity supply to be used to run household appliances and lighting.

These units have the potential to reduce the consumer's energy bill, reduce the impact on the environment by emitting less carbon dioxide and could perform well enough to enable the consumer to sell their electricity back to the grid.

Consumers with a solar PV installation could be eligible for the government's Feed-In Tariff scheme (FITs), which means they receive money from their energy supplier for the electricity that is generated, even if it is used by them, and for any surplus electricity exported to the national grid.

The energy supplier will pay a set rate for each unit (kWh) of electricity generated and will pay a further 3.1p/kWh for each unit exported back to the electricity grid.

As an accredited MCS installer, we will register the installation on the central MCS database and send a certificate confirming MCS compliance so the consumer can register for the FITs with their chosen supplier.

The total amount of electricity a solar PV system generates in a year, kilowatt hours (kWh), will depend on the system's orientation, shading and location as well as the size of the system.

The size of the system is given a rating in kilowatts peak (kWp), which is the rate at which it generates energy at peak performance at noon on a sunny day.

A typical domestic system is between 1.5 to 3kWp. Each kWp should generate around 800 to 850kWh per year if unshaded, south facing and tilting between 30-50°. A solar roof array would typically generate 1200 to 2400kWh per year depending on the size.

An average home uses 4000kWh of electricity per year on lights and appliances, not taking into account the use of A rated appliances and lighting which could reduce the annual electricity consumption.

Estimates of the solar PV systems performance will consider the pitch of the roof, its aspect and how much shading there is on the system, which does make estimating difficult as output also varies according to the season.

As a member of the REAL Assurance Scheme, consumers are guaranteed a high quality experience when buying or leasing a solar PV system. We provide consumers with a written estimate of the predicted performance before they sign a contract or a deposit is taken. We use the Government's Standard Assessment Procedure for Energy Rating of Dwellings (SAP) to assess the performance of the system.

During the design phase, we will take into account varying factors which can affect the performance of the solar PV system:

• Site location - can affect the amount of electricity generated by a solar PV system as northern areas of the UK receive slightly less energy from the sun over the course of a year but not a dramatic amount so the differences are not substantial.

• Shape of the roof area - solar PV arrays are made up of modules, which allows the most available roof space to be covered. The typical UK installations are around 15 to 25m² so a 2.9kWp system of 15 panels covering a 20m² area could generate 2450kWh per annum.

• Shading - all modules are connected so any shading on a single module affects the performance of the whole array. A solar PV system can tolerate some shading early or late in the day without much reduction of output but the optimum performance is between 10am and 4pm. Common causes of shading such as trees, chimneys and TV aerials, will be accounted for in the design. Solar PV systems do not necessarily require direct sunlight and can still generate electricity on a cloudy day.

• Orientation and tilt - the roof should ideally face due south at a pitched angle between 30-50° from the horizontal to give the best overall annual performance. Roofs facing anywhere to the south of due east and due west are feasible but installations on roofs facing north is not recommended.

• Installation - most solar PV systems are installed in 2-3 days causing minimal disruption. Scaffolding will be required if the building is more than a single storey.

The solar PV system will be commissioned according to a documented procedure to ensure that the system is safe, installed in accordance with the Microgeneration Installation Standard: MIS3002 and the manufacturers' requirements and is operating correctly in accordance with the system design.

Once the solar PV system is ready to be handed over, the consumer will be provided with a comprehensive document pack and information relating to the maintenance requirements and services available and a certificate signed by HavMain.