Solar PV Systems

To tell if a solar electricity system is right for you, there are a few key questions to consider:

1. Do you have a sunny place to put it? 
   You'll need a roof or wall that faces within 90 degrees of south, and isn't overshadowed by trees or buildings. If the surface is in shadow for parts of the day, your system will generate less energy.
   
   
2. Is your roof strong enough? 
   Solar panels are not light and the roof must be strong enough to take their weight, especially if the panel is placed on top of existing tiles. If in doubt, ask a construction expert or an installer.
   
   
4. Do you need planning permission? 
   In England and Scotland, you don't need planning permission for most home solar electricity systems, as long as they're below a certain size - but you should check with your local planning officer if your home is a listed building, or is in a conservation area or World Heritage Site. In Wales and Northern Ireland, you still need to get planning permission before installing a solar electricity system - though the legislation may soon change. To find out how to apply for permission, contact you local authority.

7. 
   Photovoltaic production has been doubling every 2 years, increasing by an average of 48 percent each year since 2002, making it the world’s fastest-growing energy technology. At the end of 2008, the cumulative global PV installations reached 15,200 megawatts. Roughly 90% of this generating capacity consists of grid connect electrical systems. Such installations may be ground-mounted (and sometimes integrated with farming and grazing) or built into the roof or walls of a building.  Solar PV power stations today have capacities ranging from 10-60 MW although proposed solar PV power stations will have a capacity of 150 MW or more.

8. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaics has declined steadily since the first solar cells were manufactured. Financial incentives, such as preferential feed in tariffs for solar-generated electricity, have supported solar PV installations in many countries. In 2004, the German government introduced the first large-scale feed-in tariff system, under a law known as the 'EEG' (Erneuerbare Energien Gesetz) which resulted in explosive growth of PV installations in Germany. At the outset the FIT was over 3x the retail price or 8x the industrial price. The principle behind the German system is a 20 year flat rate contract. The value of new contracts is programmed to decrease each year, in order to encourage the industry to pass on lower costs to the end users. The programme has been more successful than expected with over 1GW installed in 2006, and political pressure is mounting to decrease the tariff to lessen the future burden on consumers.

   Subsequently Spain, Italy, Greece (who enjoyed an early success with domestic solar-thermal installations for hot water needs) and France introduced feed-in tariffs. None have replicated the programmed decrease of FIT in new contracts though, making the German incentive relatively less and less attractive compared to other countries. The French and Greek FIT offer a high premium (EUR 0.55/kWh) for building integrated systems. California, Greece, France and Italy have 30-50% more insolation than Germany making them financially more attractive. The Greek domestic "solar roof" programme (adopted in June 2009 for installations up to 10 kW) has internal rates of return of 10-15% at current commercial installation costs, which, furthermore, is tax free.