Solar PV systems are extremely reliable. PV modules come with a 25 year warranty and have no moving parts so failures are extremely rare. The inverters for solar PV systems have 5 year warranties as standard.

DSD provide a 2 year workmanship warranty on all our solar PV installations that can be extended.

Most PV systems are roof-mounted, with mounting systems available for most roof coverings. Systems can also be ground-mounted, space permitting. Ideally, installations will face south but they can face anywhere south of due east or due west.

For maximum output, panels should be tilted at 30 to 45 degrees from the horizontal; an angle between 5 and 60 degrees is acceptable but there is a small loss of output.

Shading of just a small area of a solar PV system will significantly reduce its output because the electrical connections it contains are in series.

We will advise you whether or not your site is suitable for a solar PV system. Upon a site visit we will explain where we would propose to locate the system and what the expected electricity output would be. If your site is unsuitable for a solar PV system, we will inform you.

Prices are always changing and under review, but the price per kW can drop substantially for larger systems or multiple installations.

No. Solar PV systems generate electricity, not hot water, although the electricity can be used to heat water using an immersion heater. If you want to heat water directly you need a solar water heating system, not solar PVs.

An unshaded solar PV system facing due south and installed at an angle of 30 degrees from the horizontal can be expected to produce between 700 and 1050kWh/kWp/year in the UK.

Using a site-specific example, this means that an optimally orientated 1kWp solar PV system in London will produce 975kWh of units of electricity each year and a 2kWp system will generate 1,950kWh.

A typical 3 bedroom house in the UK built to 2010 Building Regulations standards will use 3000 – 4000 units of electricity per year, and a 2kWp solar PV system will produce roughly half of this.

However, electricity consumption can be reduced in various ways, so a 2 kWp solar PV system could supply a higher proportion of your electricity.

Most systems that we install are grid connected, so if the solar PV system is not generating enough electricity for your needs, the difference is automatically drawn from the grid. If you generate more electricity than you are using, this is automatically exported to the electricity grid (and income collected) or can be stored in a battery.

We design off-grid systems with batteries to store any excess electricity generated. Surplus energy generated by a PV installation during the day when there is little demand can be used in the evening.

We recommend that your solar PV system has a periodic inspection and test in order to protect and safeguard your investment. We offer solar maintenance services including annual service packages that can be tailored to your requirements or you can request an inspection any time you suspect a problem.

When to call us for advice?

  • For information about annual service packages and remote monitoring

  • An obvious fault has developed

  • Concerns about reduced generation

  • A change in system ownership

Unfortunately, safety regulations prevent solar PV and wind turbine systems from providing power during an outage. If the power fails your solar PV system will disconnect from the grid immediately and stop providing electricity to protect anyone working on the network. The system will automatically restart once the power cut ends.

All today’s technologies will remain dominant for years to come, with possible minor improvements to manufacturing processes.

A great deal of laboratory research into alternative technologies such as photoelectro-chemical cells, photo-synthetic cells, organic polymers, quantum well devices is in progress. However these are all decades away from volume production